Maria Rocio Lopez-Alvarez - Academia.edu (original) (raw)

Papers by Maria Rocio Lopez-Alvarez

Research paper thumbnail of Additional file 1: of qKAT: a high-throughput qPCR method for KIR gene copy number and haplotype determination

Supplementary figures S1–S9, supplementary tables S1–S14. (DOCX 2712 kb)

Research paper thumbnail of Immunogenicity of phospholipase A 2 toxins and their role in Streptococcus equi pathogenicity

Veterinary Microbiology, May 1, 2017

 Phospholipases A2 (PLA2) toxins are produced by S. equi during in vivo infection.  Anti-PLA2 a... more  Phospholipases A2 (PLA2) toxins are produced by S. equi during in vivo infection.  Anti-PLA2 antibody levels are significantly higher after exposure to S. equi.  The clinical signs of strangles are not significantly affected by the absence of PLA2 toxins.  PLA2 toxins are not essential for the development of strangles.

Research paper thumbnail of SpeS: A Novel Superantigen and Its Potential as a Vaccine Adjuvant against Strangles

International Journal of Molecular Sciences, Jun 23, 2020

Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspec... more Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspecific T cell responses accompanied by the release of proinflammatory cytokines. Streptococcus equi (S. equi) and Streptococcus zooepidemicus (S. zooepidemicus) produce sAgs that play an important role in their ability to cause disease. Strangles, caused by S. equi, is one of the most common infectious diseases of horses worldwide. Here, we report the identification of a new sAg of S. zooepidemicus, SpeS, and show that mutation of the putative T cell receptor (TCR)-binding motif (YAY to IAY) abrogated TCR-binding, whilst maintaining interaction with major histocompatibility complex (MHC) class II molecules. The fusion of SpeS and SpeS Y39I to six S. equi surface proteins using two different peptide linkers was conducted to determine if MHC class II-binding properties were maintained. Proliferation assays, qPCR and flow cytometry analysis showed that SpeS Y39I and its fusion proteins induced less mitogenic activity and interferon gamma expression when compared to SpeS, whilst retaining Antigen-Presenting Cell (APC)-binding properties. Our data suggest that SpeS Y39I-surface protein fusions could be used to direct vaccine antigens towards antigen-presenting cells in vivo with the potential to enhance antigen presentation and improve immune responses.

Research paper thumbnail of Refinement of the equine influenza model in the natural host: A meta-analysis to determine the benefits of individual nebulisation for experimental infection and vaccine evaluation in the face of decreased strain pathogenicity

Veterinary Microbiology, Nov 1, 2017

Equine Influenza (EI) is an important respiratory disease of horses caused by H3N8 equine influen... more Equine Influenza (EI) is an important respiratory disease of horses caused by H3N8 equine influenza viruses (EIV). Vaccination is a key strategy to prevent or control this disease. However, EIV undergoes continuous antigenic drift and whilst numerous EI vaccines are commercially available worldwide, an accurate evaluation of their efficacy is frequently required through clinical trials conducted in the natural host. Room nebulisation is one of the chosen methods to challenge horses during EI vaccine studies. A potential decreased pathogenicity observed with recent Florida Clade 2 (FC2) EIV isolates have increased the heterogeneity of the clinical response and virus shedding measured after infection by room nebulisation, which reduced the statistical power of studies. Our objectives were to compare clinical and virological parameters following experimental infection with several different EIV strains and to confirm that individual nebulisation is a model refinement that prevents an increase of the number of animals per group. This study is a retrospective comparison and meta-analysis of clinical and virological results collected from 9 independent EIV infection studies in the natural host. Naïve Welsh mountain ponies were experimentally infected by room or individual nebulisation with FC2 EIV strains, including A

Research paper thumbnail of Immunological Risk Stratification of Bladder Cancer Based on Peripheral Blood Natural Killer Cell Biomarkers

European Urology Oncology, 2019

Background: Bladder cancer (BC) is highly immunogenic. Bacillus Calmette-Guérin (BCG) immunothera... more Background: Bladder cancer (BC) is highly immunogenic. Bacillus Calmette-Guérin (BCG) immunotherapy offers the best results in non-muscle-invasive BC (NMIBC). Natural killer cells (NKcs) play decisive roles in BCG-mediated immune response and in general cancer immune-surveillance. Objective: To analyze killer-cell immunoglobulin-like receptors (KIRs), their human leukocyte antigen class-I (HLA-I) ligands, and the expression of DNAX Accessory Molecule-1 (DNAM-1/CD226) on peripheral blood (PB) NKcs, to identify useful predictive biomarkers in BC. Design, setting, and participants: KIR/HLA-ligand genotypes were compared between 132 BC, 201 other solid cancers, 164 plasma cell disorders, and 615 healthy Caucasoid controls. CD226 expression was evaluated by flow cytometry. Outcome measurements and statistical analysis: KIR/HLA-I interactions and CD226 expression on NKcs (CD226 high or CD226 low) were compared across study groups, cancer stages, treatments, and progression-free and overall survival of patients, using chi-square, analysis of variance/post hoc, Kaplan-Meier/log-rank, and regression analyses. Results and limitations: Three immunological risk groups were identified: low risk (KIR2DL1 À L2 + L3 À /C1C1 À and KIR2DL1 + L2 + L3 + /C1C1 +), intermediate risk (rest), and high risk (KIR2DL5 + /HLA-C*16 + and KIR2DL1 + L2 + L3 À), which displayed different 10-yr progression-free rates (83.3%, 48.6%, and 0%, respectively; p < 0.001) and survival rates (83.3%, 54.3%, and 6.2%, respectively; p < 0.001) for muscle-invasive T2/T4, and 10-yr progression-free rates (100%, 81.6%, and 50%, respectively; 1 C.F. Guillamón and L. Gimeno contributed equally to this article.

Research paper thumbnail of NKG2D Polymorphism in Melanoma Patients from Southeastern Spain

Cancers, 2019

Background: Natural killer (NK) and CD8+ T cells are involved in the immune response against mela... more Background: Natural killer (NK) and CD8+ T cells are involved in the immune response against melanoma. C-Type lectin-like NK cell receptors are located in the Natural Killer Complex (NKC) region 12p13.2-p12.3 and play a critical role in regulating the activity of NK and CD8+ T cells. An association between polymorphisms in the NKC region, including the NKG2D gene and NKG2A promoter, and the risk of cancer has been previously described. The aim of this study was to analyze the association of polymorphisms in the NKC region with cutaneous melanoma in patients from southeastern Spain. Methods: Seven single-nucleotide polymorphisms (SNPs) in the NKG2D gene (NKC3,4,7,9,10,11,12), and one SNP in the NKG2A promoter (NKC17) were genotyped by a TaqMan 5′ Nuclease Assay in 233 melanoma patients and 200 matched healthy controls. Results: A linkage disequilibrium analysis of the SNPs performed in the NKC region revealed two blocks of haplotypes (Hb-1 and Hb-2) with 14 and seven different haplot...

Research paper thumbnail of A comprehensive analysis of e-CAS cell line reveals they are mouse macrophages

Scientific reports, Jan 29, 2018

The 3Rs principles (Replacement, Reduction and Refinement) are focused on finding alternatives to... more The 3Rs principles (Replacement, Reduction and Refinement) are focused on finding alternatives to the use of animals in research. In this regard, cell lines are popular and useful tools for the replacement of primary cells in in vitro studies. However, around 15-30% of cell lines used in research have been misidentified or cross-contaminated generating concerns about the results obtained from experiments that use them. Here we described how old aliquots of an equine macrophage cell line (e-CAS) stored at the Animal Health Trust did not contain equine cells but macrophages of murine origin (m-CAS).

Research paper thumbnail of SzeQ, a novel Streptococcus zooepidemicus superantigen that stimulates both T-lymphocytes and Antigen Presenting Cells

Journal of Equine Veterinary Science, 2016

Research paper thumbnail of qKAT: a high-throughput qPCR method for KIR gene copy number and haplotype determination

Genome Medicine, 2016

Killer cell immunoglobulin-like receptors (KIRs), expressed on natural killer cells and T cells, ... more Killer cell immunoglobulin-like receptors (KIRs), expressed on natural killer cells and T cells, have considerable biomedical relevance playing significant roles in immunity, pregnancy and transplantation. The KIR locus is one of the most complex and polymorphic regions of the human genome. Extensive sequence homology and copy number variation makes KIRs technically laborious and expensive to type. To aid the investigation of KIRs in human disease we developed a high-throughput, multiplex real-time polymerase chain reaction method to determine gene copy number for each KIR locus. We used reference DNA samples to validate the accuracy and a cohort of 1698 individuals to evaluate capability for precise copy number discrimination. The method provides improved information and identifies KIR haplotype alterations that were not previously visible using other approaches.

Research paper thumbnail of Analysis of CD95 and CD28 Expression on Peripheral Blood T Cells: A Clue to Differentiate Acute Rejection from HBV And/Or HCV Liver Graft Re-Infection

Transplantation Journal, 2004

Liver transplantation for nonresectable liver metastasis from colorectal cancer was discontinued ... more Liver transplantation for nonresectable liver metastasis from colorectal cancer was discontinued in 1994 on account of high recurrence rates and limited long-term survival. In this retrospective study, we investigated whether the genetic detection of micrometastasis in histologically negative lymph nodes after primary colon cancer can be applied to select patients for liver transplantation. Methods: Tumor material was gathered from 21 patients with colorectal cancer and subsequent liver metastasis. The patients had undergone a liver transplant within the 1983-1994 interval. Direct DNA sequencing was used to screen the tumor material for p53 mutations. Eleven of these patients had shown no histologically detectable lymph node metastasis at the time of surgery (pN0), 10 patients with lymph node metastasis (pN1) served as control group. We used mutant allele-specific amplification (MASA) to identify corresponding genetic alterations in regional lymph nodes from colorectal cancer. Results: Overall, p53 mutations were found in 13 of 21 patients in the primary colorectal cancer. These mutations were confirmed in the corresponding liver metastasis. MASA technology proved the existence of micrometastasis in the histologically positive lymph nodes of the control group. Nine of eleven histologically lymph nodenegative patients were evaluable due to presence of p53 mutation. MASA revealed 6/9 patients to be genetically positive for micrometastasis. Three patients were genetically a n d histologically negative. These 3 patients showed a significantly longer overall survival (pϭ0.011) of 4, 5 and 20 years, respectively. Conclusions: p53 MASA is a sensitive technique to identify micrometastasis in histologically negative lymph nodes following primary cancer in patients who present with nonresectable liver metastasis. Patients who are genetically positive do not benefit from liver transplantation. For patients without micrometastasis, liver transplantation seems to be a treatment option. The genetic detection of micrometastasis by MASA could be a powerful prognostic indicator to select those who benefit from liver transplantation.

Research paper thumbnail of II Simposium Internacional sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica

Inmunología, 2012

sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica II ... more sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica II International symposium on immune tolerance: application to transplantation and immune diseases

Research paper thumbnail of Hemophagocytic lymphohistiocytosis: Overview and diagnostic procedure. A case induced by an expansion of monoclonal EBV-negative NK cells

Inmunología, 2009

RESUMEN Las causas más comunes de linfohistiocitosis hemofagocítica (HLH) son expansiones clonale... more RESUMEN Las causas más comunes de linfohistiocitosis hemofagocítica (HLH) son expansiones clonales de células NK y T, inducidas por EBV, así como las alteraciones genéticas que comprometen la actividad asesina de las NKs. Generalmente, HLH se desencadena por una disfunción inmune en la que se desarrolla hipercitoquinemia. En este trabajo se resumen las causas más comunes de HLH y se presenta un caso en el que una expansión monoclonal de células NK, EBV-negativas, se asocia a HLH en una paciente aquejada de Síndrome de Griscelli tipo-2 (GS2). Se trata de una niña de 17 meses con una mutación de nueva descripción en RAB27A, con albinismo parcial, fiebre persistente, hepatoesplenomegalia, adenopatías y citopenias al diagnóstico. No se detectaron evidencias de infecciones virales activas, incluida EBV. Se detectó una expansión de células NKs (5300/µl) CD2 + CD7 + CD8 + CD16 + CD56 + CD94 + CD158a/h + CD158b/j-Perforin + Granzyme-B +. Tras el tratamiento (Protocolo HLH-2004: Cyclosporina, Etoposido y Dexametasona), la cifra de células NK se redujo a 850/µl y que aumentaron progresivamente hasta alcanzar niveles similares al diagnóstico. El ensayo de inactivación del cromosoma X demostró monoclonalidad de células NK. Dichas células mantenían intacta su actividad asesina y secretaban grandes cantidades de IFN-γ. Al diagnóstico los niveles séricos de sIL-2R (36.8 ng/ml) e IFN-γ (400 pg/ml) estaban elevados. En conclusión, se describe un caso de una expansión monoclonal de células NK, EBV-negativas, que secretan grandes cantidades de IFN-γ como la causa más probable del episodio de HLH en una paciente con GS2. Tras el trasplante de médula ósea de su hermana HLA-idéntica, las cifras y el fenotipo de las células NK recobraron la normalidad. PALABRAS CLAVE: Expansión de células NK monoclonales / Linfohistiocitosis hemofagocítica / Síndrome de Griscelli tipo-2 / Mutación de RAB27A / EBV / IFN-γ. ABSTRACT Clonal natural killer (NK) and T cell expansions induced by Epstein-Barr virus (EBV) and genetic alterations compromising NK cell killing are the most common causes of hemophagocytic lymphohistocytosis (HLH). Generally, HLH is induced by an immune dysfunction where hypercytokinemia develops into reactive hemophagocytosis. In this work we review the causes of HLH and describe a case of a monoclonal expansion of EBV-negative NK cells associated to HLH in a seventeen-month-old girl suffering of Griscelli syndrome type-2 with novel RAB27A mutation and showing partial albinism, persistent fever, hepatosplenomegaly, adenopaties and cytopenias. At diagnosis, no evidence of active viral infections, including EBV, was found. Expansion of NK cells (5300/µl in peripheral blood) CD2 + CD7 + CD8 + CD16 + CD56 + CD94 + CD158a/h + CD158b/j-Perforin + Granzyme B + was found. After treatment (HLH-2004 protocol: Cyclosporin, Etoposide and Dexamethasone), NK cell count fell to 850/µl and progressively increased to pre-therapy levels by week 28. X-chromosome inactivation assay demonstrated NK cell monoclonality. NK cells sustained a strong killing and secreted high amounts of IFN-γ. At diagnosis, serum levels of sIL-2R (36,8 ng/ml) and IFN-γ (400 pg/ml) were elevated. In conclusion, we describe a monoclonal expansion of EBV-negative NK cells highly secretory of IFN-γ as the most probable cause of HLH episode in a patient with Griscelli syndrome type-2. NK cell count recovered normal levels and phenotype after bone marrow transplantation from her HLA identical sister.

Research paper thumbnail of KIR Gene Mismatching and KIR/C Ligands in Liver Transplantation

Transplantation, 2013

Background. Killer immunoglobulin-like receptors (KIRs) bind human leukocyte antigen (HLA) class-... more Background. Killer immunoglobulin-like receptors (KIRs) bind human leukocyte antigen (HLA) class-I (HLA-I) ligands and regulate functions of natural killer cells and subsets of T cells. KIR/HLA-I interactions allow predicting natural killer cell alloreactivity in hematopoietic stem cell transplantation and in HLA-compatible kidney transplants, but its meaning in liver transplantation remains controversial. Methods. KIR and HLA genotypes were studied in 402 liver transplants, using sequence-specific oligonucleotides and primer methods. Recipients and donor KIRs, HLA-C genotypes, KIR gene mismatches (MMs) between recipientdonor pairs, and KIR/HLA-ligand combinations were analyzed in overall transplantations, in the acute rejection (AR; n=110) and non-AR (n=292) groups. Results. KIR gene MMs between recipients and donors, mainly in activating KIRs, and KIR2DL3 and KIR2DS1 of recipients in the presence of donor C2 ligands, significantly enhanced early AR rate (PG0.05), with KIR2DL3 + and KIR2DS1 + exhibiting a synergic effect in dependence of the donor C2 ligand number (W2=7.662, P=0.022). KIR2DL3, KIR2DS1, and also KIR2DS4 + significantly influenced short-term graft survival, with a benefit for transplantations combining KIR2DL3 + recipients and donors having C1 ligands (log rank, PG0.019 at 1 year; hazards ratio [HR], 0.321; 95% confidence interval [CI], 0.107Y0.962; P=0.042), whereas KIR2DS1 + and KIR2DS4 + recipients combined with donors lacking C1 ligands (C2/C2) exhibited a worse graft survival (log rank, P=0.035 at 6 months; HR, 7.713; 95% CI, 2.156Y27.369; P=0.002 for KIR2DS1 + ; and log rank, P=0.006 at 1 year; HR, 3.794; 95% CI, 1.267Y11.365; P=0.017 for KIR2DS4). Conclusions. This study shows that KIR gene-gene MMs increase AR and that KIRs/C ligands associated to AR and KIR2DS4 + /C ligands also influence short-term graft survival.

Research paper thumbnail of Balance of Circulating CD4+CD25+ and CD4+CD25+CTLA-4+ T Cells Could Play a Role in the Individual Commitment for the Short-Term Liver Graft Acceptance

Transplantation Journal, 2004

Aims: Chronic renal failure (CRF) is a recognized complication of organ transplantation and sever... more Aims: Chronic renal failure (CRF) is a recognized complication of organ transplantation and several risk factors there exist, linked both to patients and the procedure, which can favor its development. The aim of this study was to assess the incidence of post-transplantation CRF in a population of liver transplanted patients and to investigate the presence of possible risk factors for developing renal dysfunction. Methods: We performed a retrospective study on the liver-transplanted patients referring to liver transplantation ambulatory of "Tor Vergata" University of Rome and investigated the incidence of CRF and eventual need for renal replacement therapy (RRT). Furthermore, we searched for some possible risk factors for CRF development, such as systemic hypertension (SH), dyslipidemia, Diabetes Mellitus (DM), HBV and HCV status and calcyneurin inhibitors therapy. Results: From 1992 to today, 261 ortotopic liver transplantation have been performed at our Centre. In the post-transplantation period, 22 patients (8,4 %) developed chronic renal failure and were treated with standard intermittent hemodialysis (for a men time of 3 weeks). Among these, four male patients and one female subject have developed end stage renal disease (ESRD) and at present need chronic RRT. Further data about ESRD patients are reported in the Table below. One of them has died for cardiovascular complications during dialytic session. Among the remaining 17 patients, 5 subjects (29,5%) were HCV positive, 9/17 (52,9%) showed SH, 2/17 (11,8%) showed DM and 10/17 (58,8%) were treated with CsA. They partially recovered their renal function and are at present under conservative therapy. Conclusions: CRF proved to be a relatively common complication in our liver transplanted patients, confirming data reported in literature. Risk factors for developing renal dysfunction present in our patients are also cardiovascular risk factors and this could lead to an increase in mortality for cardiovascular pathology, particularly incident in uremic patients. It could be useful to pay attention to pretransplant renal dysfunction, modifiable cardiovascular risk factors and immunosuppressant protocol in order to avoid CRF onset in liver transplanted patients, thus obtaining a reduction of morbidity and mortality and of the costs for the National Sanitary System.

Research paper thumbnail of CD80 and CD86 Down-Modulation in Peripheal Blood Lymphocyte from Liver Recipients with a Good Graft Acceptance

Research paper thumbnail of Influence of human leukocyte antigen mismatching on rejection development and allograft survival in liver transplantation: Is the relevance of HLA-A locus matching being underestimated?

Transplant Immunology, 2012

The influence of HLA matching on liver transplant is still controversial, as studies have failed ... more The influence of HLA matching on liver transplant is still controversial, as studies have failed to demonstrate an adverse effect of HLA mismatching on transplant outcome. We examined the effect of HLA mismatching on transplant outcome in a series of 342 consecutive liver transplants (224 finally analyzed). HLA typing was performed by serological and molecular methods. HLA-A matching was associated with an increased chronic rejection incidence (P = 0.04). Indeed, HLA-A match also demonstrated a significant impact on allograft survival (P = 0.03), confirming previous observation concerning to rejection, as complete HLA-A mismatching favored a better liver transplant outcome. Analysis of HLA-A + B + DR matching also demonstrated a significant impact on graft survival (P b 0.05). Multivariate Cox regression analysis confirmed the effect of HLA-A and DPB1 matching as independent risk factors for graft loss. Another independent factor was a positive pre-transplant crossmatch. In conclusion, liver transplant outcome has not been found to be improved by HLA matching, however a poorer HLA compatibility favored a better graft survival and decreased rejection incidence, with a special relevance for HLA-A matching.

Research paper thumbnail of KIR gene variability in cutaneous malignant melanoma: influence of KIR2D/HLA-C pairings on disease susceptibility and prognosis

Immunogenetics, 2013

Natural killer and CD8(+) T cells are believed to be involved in the immune protection against me... more Natural killer and CD8(+) T cells are believed to be involved in the immune protection against melanoma. Their function may be regulated by a group of receptors defined as killer immunoglobulin-like receptors (KIRs) and their cognate HLA class I ligands. In this study, we analyzed the influence of KIR genes and KIR/HLA-I combinations on melanoma susceptibility and/or prognosis in a Spanish Caucasian population. For this purpose, KIR genotyping by PCR-SSP and HLA-C genotyping by reverse PCR-SSO were performed in 187 melanoma patients and 200 matched controls. We found a significantly low frequency of KIR2DL3 in nodular melanoma (NM) patients (P = 0.001) and in ulcerated melanoma patients (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001). Similarly, the KIR2DL3/C1 combination was significantly decreased in melanoma patients (Pc = 0.008) and in patients with sentinel lymph node (SLN) melanoma metastasis (Pc = 0.002). Multivariate logistic regression models showed that KIR2DL3 behaves as a protective marker for NM and ulcerated melanoma (P = 0.02, odds ratio (OR) = 0.14 and P = 0.04, OR = 0.28, respectively), whereas the KIR2DL3/C1 pair acts as a protective marker for melanoma (P = 0.017, OR = 0.54), particularly superficial spreading melanoma (P = 0.02, OR = 0.52), and SLN metastasis (P = 0.0004, OR = 0.14). In contrast, the KIR2DL3(-)/C1C2 genotype seems to be correlated with NM and ulceration. We also report that the KIR2DL1(+)/S1(-)/C2C2 genotype is associated with susceptibility to melanoma and SLN metastasis. Altogether, the study of KIR2D genes and HLA-C ligands may help in assessing cutaneous melanoma risk and prognosis.

Research paper thumbnail of Post-transplant increase in soluble human leukocyte antigen-G associated with non-severe cardiac allograft vasculopathy

Human Immunology, 2013

Cardiac allograft vasculopathy (CAV) is the single most important long-term limitation to heart t... more Cardiac allograft vasculopathy (CAV) is the single most important long-term limitation to heart transplantation. This study aimed to assess the value of monitoring soluble human leukocyte antigen-G (sHLA-G) during the first year post-transplantation to predict the severity of CAV, in 21 out of 77 heart recipients assessed by intravascular ultrasound (IVUS). Serum sHLA-G concentration increased after transplant in recipients free of severe CAV, but decreased in recipients suffering from severe CAV, significant differences between these two groups were found 6 to 12 months post-transplantation. The optimal value of the change in post-transplant sHLA-G for identifying severe CAV was P0.062%, which maximized sensitivity (80%) and specificity (100%). Importantly, increases in post-transplant sHLA-G were inversely associated with severe CAV, but directly associated with human cytomegalovirus reactivation. In addition, recipients presenting non-severe CAV or an increased sHLA-G post-transplantation, showed higher numbers of CD8 + CD28 À T cells and a down-modulation of CD28 on CD4 + lymphocytes, which typically identifies CD8 + regulatory T cells and anergic/tolerogenic T helper cells, respectively. In conclusion, quantification of sHLA-G might offer a complementary non-invasive method for identifying recipients at risk of more severe CAV and who might benefit from earlier preventive therapies, although these results need to be confirmed in larger series.

Research paper thumbnail of LILRA6 copy number variation correlates with susceptibility to atopic dermatitis

Immunogenetics, Jan 22, 2016

Leukocyte immunoglobulin-like receptors (LILR) are expressed mostly on myelomonocytic cells where... more Leukocyte immunoglobulin-like receptors (LILR) are expressed mostly on myelomonocytic cells where they are mediators of immunological tolerance. Two LILR genes, LILRA3 and LILRA6, exhibit marked copy number variation. We assessed the contribution of these genes to atopic dermatitis (AD) by analysing transmission in 378 AD families. The data indicated that copies of LILRA6 were over-transmitted to affected patients. They are consistent with a contribution of LILR genes to AD. They could affect the equilibrium between activating and inhibitory signals in the immune response.

Research paper thumbnail of SpeS: A Novel Superantigen and Its Potential as a Vaccine Adjuvant against Strangles

International Journal of Molecular Sciences

Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspec... more Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspecific T cell responses accompanied by the release of proinflammatory cytokines. Streptococcus equi (S. equi) and Streptococcus zooepidemicus (S. zooepidemicus) produce sAgs that play an important role in their ability to cause disease. Strangles, caused by S. equi, is one of the most common infectious diseases of horses worldwide. Here, we report the identification of a new sAg of S. zooepidemicus, SpeS, and show that mutation of the putative T cell receptor (TCR)-binding motif (YAY to IAY) abrogated TCR-binding, whilst maintaining interaction with major histocompatibility complex (MHC) class II molecules. The fusion of SpeS and SpeSY39I to six S. equi surface proteins using two different peptide linkers was conducted to determine if MHC class II-binding properties were maintained. Proliferation assays, qPCR and flow cytometry analysis showed that SpeSY39I and its fusion proteins induced ...

Research paper thumbnail of Additional file 1: of qKAT: a high-throughput qPCR method for KIR gene copy number and haplotype determination

Supplementary figures S1–S9, supplementary tables S1–S14. (DOCX 2712 kb)

Research paper thumbnail of Immunogenicity of phospholipase A 2 toxins and their role in Streptococcus equi pathogenicity

Veterinary Microbiology, May 1, 2017

 Phospholipases A2 (PLA2) toxins are produced by S. equi during in vivo infection.  Anti-PLA2 a... more  Phospholipases A2 (PLA2) toxins are produced by S. equi during in vivo infection.  Anti-PLA2 antibody levels are significantly higher after exposure to S. equi.  The clinical signs of strangles are not significantly affected by the absence of PLA2 toxins.  PLA2 toxins are not essential for the development of strangles.

Research paper thumbnail of SpeS: A Novel Superantigen and Its Potential as a Vaccine Adjuvant against Strangles

International Journal of Molecular Sciences, Jun 23, 2020

Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspec... more Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspecific T cell responses accompanied by the release of proinflammatory cytokines. Streptococcus equi (S. equi) and Streptococcus zooepidemicus (S. zooepidemicus) produce sAgs that play an important role in their ability to cause disease. Strangles, caused by S. equi, is one of the most common infectious diseases of horses worldwide. Here, we report the identification of a new sAg of S. zooepidemicus, SpeS, and show that mutation of the putative T cell receptor (TCR)-binding motif (YAY to IAY) abrogated TCR-binding, whilst maintaining interaction with major histocompatibility complex (MHC) class II molecules. The fusion of SpeS and SpeS Y39I to six S. equi surface proteins using two different peptide linkers was conducted to determine if MHC class II-binding properties were maintained. Proliferation assays, qPCR and flow cytometry analysis showed that SpeS Y39I and its fusion proteins induced less mitogenic activity and interferon gamma expression when compared to SpeS, whilst retaining Antigen-Presenting Cell (APC)-binding properties. Our data suggest that SpeS Y39I-surface protein fusions could be used to direct vaccine antigens towards antigen-presenting cells in vivo with the potential to enhance antigen presentation and improve immune responses.

Research paper thumbnail of Refinement of the equine influenza model in the natural host: A meta-analysis to determine the benefits of individual nebulisation for experimental infection and vaccine evaluation in the face of decreased strain pathogenicity

Veterinary Microbiology, Nov 1, 2017

Equine Influenza (EI) is an important respiratory disease of horses caused by H3N8 equine influen... more Equine Influenza (EI) is an important respiratory disease of horses caused by H3N8 equine influenza viruses (EIV). Vaccination is a key strategy to prevent or control this disease. However, EIV undergoes continuous antigenic drift and whilst numerous EI vaccines are commercially available worldwide, an accurate evaluation of their efficacy is frequently required through clinical trials conducted in the natural host. Room nebulisation is one of the chosen methods to challenge horses during EI vaccine studies. A potential decreased pathogenicity observed with recent Florida Clade 2 (FC2) EIV isolates have increased the heterogeneity of the clinical response and virus shedding measured after infection by room nebulisation, which reduced the statistical power of studies. Our objectives were to compare clinical and virological parameters following experimental infection with several different EIV strains and to confirm that individual nebulisation is a model refinement that prevents an increase of the number of animals per group. This study is a retrospective comparison and meta-analysis of clinical and virological results collected from 9 independent EIV infection studies in the natural host. Naïve Welsh mountain ponies were experimentally infected by room or individual nebulisation with FC2 EIV strains, including A

Research paper thumbnail of Immunological Risk Stratification of Bladder Cancer Based on Peripheral Blood Natural Killer Cell Biomarkers

European Urology Oncology, 2019

Background: Bladder cancer (BC) is highly immunogenic. Bacillus Calmette-Guérin (BCG) immunothera... more Background: Bladder cancer (BC) is highly immunogenic. Bacillus Calmette-Guérin (BCG) immunotherapy offers the best results in non-muscle-invasive BC (NMIBC). Natural killer cells (NKcs) play decisive roles in BCG-mediated immune response and in general cancer immune-surveillance. Objective: To analyze killer-cell immunoglobulin-like receptors (KIRs), their human leukocyte antigen class-I (HLA-I) ligands, and the expression of DNAX Accessory Molecule-1 (DNAM-1/CD226) on peripheral blood (PB) NKcs, to identify useful predictive biomarkers in BC. Design, setting, and participants: KIR/HLA-ligand genotypes were compared between 132 BC, 201 other solid cancers, 164 plasma cell disorders, and 615 healthy Caucasoid controls. CD226 expression was evaluated by flow cytometry. Outcome measurements and statistical analysis: KIR/HLA-I interactions and CD226 expression on NKcs (CD226 high or CD226 low) were compared across study groups, cancer stages, treatments, and progression-free and overall survival of patients, using chi-square, analysis of variance/post hoc, Kaplan-Meier/log-rank, and regression analyses. Results and limitations: Three immunological risk groups were identified: low risk (KIR2DL1 À L2 + L3 À /C1C1 À and KIR2DL1 + L2 + L3 + /C1C1 +), intermediate risk (rest), and high risk (KIR2DL5 + /HLA-C*16 + and KIR2DL1 + L2 + L3 À), which displayed different 10-yr progression-free rates (83.3%, 48.6%, and 0%, respectively; p < 0.001) and survival rates (83.3%, 54.3%, and 6.2%, respectively; p < 0.001) for muscle-invasive T2/T4, and 10-yr progression-free rates (100%, 81.6%, and 50%, respectively; 1 C.F. Guillamón and L. Gimeno contributed equally to this article.

Research paper thumbnail of NKG2D Polymorphism in Melanoma Patients from Southeastern Spain

Cancers, 2019

Background: Natural killer (NK) and CD8+ T cells are involved in the immune response against mela... more Background: Natural killer (NK) and CD8+ T cells are involved in the immune response against melanoma. C-Type lectin-like NK cell receptors are located in the Natural Killer Complex (NKC) region 12p13.2-p12.3 and play a critical role in regulating the activity of NK and CD8+ T cells. An association between polymorphisms in the NKC region, including the NKG2D gene and NKG2A promoter, and the risk of cancer has been previously described. The aim of this study was to analyze the association of polymorphisms in the NKC region with cutaneous melanoma in patients from southeastern Spain. Methods: Seven single-nucleotide polymorphisms (SNPs) in the NKG2D gene (NKC3,4,7,9,10,11,12), and one SNP in the NKG2A promoter (NKC17) were genotyped by a TaqMan 5′ Nuclease Assay in 233 melanoma patients and 200 matched healthy controls. Results: A linkage disequilibrium analysis of the SNPs performed in the NKC region revealed two blocks of haplotypes (Hb-1 and Hb-2) with 14 and seven different haplot...

Research paper thumbnail of A comprehensive analysis of e-CAS cell line reveals they are mouse macrophages

Scientific reports, Jan 29, 2018

The 3Rs principles (Replacement, Reduction and Refinement) are focused on finding alternatives to... more The 3Rs principles (Replacement, Reduction and Refinement) are focused on finding alternatives to the use of animals in research. In this regard, cell lines are popular and useful tools for the replacement of primary cells in in vitro studies. However, around 15-30% of cell lines used in research have been misidentified or cross-contaminated generating concerns about the results obtained from experiments that use them. Here we described how old aliquots of an equine macrophage cell line (e-CAS) stored at the Animal Health Trust did not contain equine cells but macrophages of murine origin (m-CAS).

Research paper thumbnail of SzeQ, a novel Streptococcus zooepidemicus superantigen that stimulates both T-lymphocytes and Antigen Presenting Cells

Journal of Equine Veterinary Science, 2016

Research paper thumbnail of qKAT: a high-throughput qPCR method for KIR gene copy number and haplotype determination

Genome Medicine, 2016

Killer cell immunoglobulin-like receptors (KIRs), expressed on natural killer cells and T cells, ... more Killer cell immunoglobulin-like receptors (KIRs), expressed on natural killer cells and T cells, have considerable biomedical relevance playing significant roles in immunity, pregnancy and transplantation. The KIR locus is one of the most complex and polymorphic regions of the human genome. Extensive sequence homology and copy number variation makes KIRs technically laborious and expensive to type. To aid the investigation of KIRs in human disease we developed a high-throughput, multiplex real-time polymerase chain reaction method to determine gene copy number for each KIR locus. We used reference DNA samples to validate the accuracy and a cohort of 1698 individuals to evaluate capability for precise copy number discrimination. The method provides improved information and identifies KIR haplotype alterations that were not previously visible using other approaches.

Research paper thumbnail of Analysis of CD95 and CD28 Expression on Peripheral Blood T Cells: A Clue to Differentiate Acute Rejection from HBV And/Or HCV Liver Graft Re-Infection

Transplantation Journal, 2004

Liver transplantation for nonresectable liver metastasis from colorectal cancer was discontinued ... more Liver transplantation for nonresectable liver metastasis from colorectal cancer was discontinued in 1994 on account of high recurrence rates and limited long-term survival. In this retrospective study, we investigated whether the genetic detection of micrometastasis in histologically negative lymph nodes after primary colon cancer can be applied to select patients for liver transplantation. Methods: Tumor material was gathered from 21 patients with colorectal cancer and subsequent liver metastasis. The patients had undergone a liver transplant within the 1983-1994 interval. Direct DNA sequencing was used to screen the tumor material for p53 mutations. Eleven of these patients had shown no histologically detectable lymph node metastasis at the time of surgery (pN0), 10 patients with lymph node metastasis (pN1) served as control group. We used mutant allele-specific amplification (MASA) to identify corresponding genetic alterations in regional lymph nodes from colorectal cancer. Results: Overall, p53 mutations were found in 13 of 21 patients in the primary colorectal cancer. These mutations were confirmed in the corresponding liver metastasis. MASA technology proved the existence of micrometastasis in the histologically positive lymph nodes of the control group. Nine of eleven histologically lymph nodenegative patients were evaluable due to presence of p53 mutation. MASA revealed 6/9 patients to be genetically positive for micrometastasis. Three patients were genetically a n d histologically negative. These 3 patients showed a significantly longer overall survival (pϭ0.011) of 4, 5 and 20 years, respectively. Conclusions: p53 MASA is a sensitive technique to identify micrometastasis in histologically negative lymph nodes following primary cancer in patients who present with nonresectable liver metastasis. Patients who are genetically positive do not benefit from liver transplantation. For patients without micrometastasis, liver transplantation seems to be a treatment option. The genetic detection of micrometastasis by MASA could be a powerful prognostic indicator to select those who benefit from liver transplantation.

Research paper thumbnail of II Simposium Internacional sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica

Inmunología, 2012

sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica II ... more sobre tolerancia inmunológica: aplicación al trasplante y a enfermedades de base inmunológica II International symposium on immune tolerance: application to transplantation and immune diseases

Research paper thumbnail of Hemophagocytic lymphohistiocytosis: Overview and diagnostic procedure. A case induced by an expansion of monoclonal EBV-negative NK cells

Inmunología, 2009

RESUMEN Las causas más comunes de linfohistiocitosis hemofagocítica (HLH) son expansiones clonale... more RESUMEN Las causas más comunes de linfohistiocitosis hemofagocítica (HLH) son expansiones clonales de células NK y T, inducidas por EBV, así como las alteraciones genéticas que comprometen la actividad asesina de las NKs. Generalmente, HLH se desencadena por una disfunción inmune en la que se desarrolla hipercitoquinemia. En este trabajo se resumen las causas más comunes de HLH y se presenta un caso en el que una expansión monoclonal de células NK, EBV-negativas, se asocia a HLH en una paciente aquejada de Síndrome de Griscelli tipo-2 (GS2). Se trata de una niña de 17 meses con una mutación de nueva descripción en RAB27A, con albinismo parcial, fiebre persistente, hepatoesplenomegalia, adenopatías y citopenias al diagnóstico. No se detectaron evidencias de infecciones virales activas, incluida EBV. Se detectó una expansión de células NKs (5300/µl) CD2 + CD7 + CD8 + CD16 + CD56 + CD94 + CD158a/h + CD158b/j-Perforin + Granzyme-B +. Tras el tratamiento (Protocolo HLH-2004: Cyclosporina, Etoposido y Dexametasona), la cifra de células NK se redujo a 850/µl y que aumentaron progresivamente hasta alcanzar niveles similares al diagnóstico. El ensayo de inactivación del cromosoma X demostró monoclonalidad de células NK. Dichas células mantenían intacta su actividad asesina y secretaban grandes cantidades de IFN-γ. Al diagnóstico los niveles séricos de sIL-2R (36.8 ng/ml) e IFN-γ (400 pg/ml) estaban elevados. En conclusión, se describe un caso de una expansión monoclonal de células NK, EBV-negativas, que secretan grandes cantidades de IFN-γ como la causa más probable del episodio de HLH en una paciente con GS2. Tras el trasplante de médula ósea de su hermana HLA-idéntica, las cifras y el fenotipo de las células NK recobraron la normalidad. PALABRAS CLAVE: Expansión de células NK monoclonales / Linfohistiocitosis hemofagocítica / Síndrome de Griscelli tipo-2 / Mutación de RAB27A / EBV / IFN-γ. ABSTRACT Clonal natural killer (NK) and T cell expansions induced by Epstein-Barr virus (EBV) and genetic alterations compromising NK cell killing are the most common causes of hemophagocytic lymphohistocytosis (HLH). Generally, HLH is induced by an immune dysfunction where hypercytokinemia develops into reactive hemophagocytosis. In this work we review the causes of HLH and describe a case of a monoclonal expansion of EBV-negative NK cells associated to HLH in a seventeen-month-old girl suffering of Griscelli syndrome type-2 with novel RAB27A mutation and showing partial albinism, persistent fever, hepatosplenomegaly, adenopaties and cytopenias. At diagnosis, no evidence of active viral infections, including EBV, was found. Expansion of NK cells (5300/µl in peripheral blood) CD2 + CD7 + CD8 + CD16 + CD56 + CD94 + CD158a/h + CD158b/j-Perforin + Granzyme B + was found. After treatment (HLH-2004 protocol: Cyclosporin, Etoposide and Dexamethasone), NK cell count fell to 850/µl and progressively increased to pre-therapy levels by week 28. X-chromosome inactivation assay demonstrated NK cell monoclonality. NK cells sustained a strong killing and secreted high amounts of IFN-γ. At diagnosis, serum levels of sIL-2R (36,8 ng/ml) and IFN-γ (400 pg/ml) were elevated. In conclusion, we describe a monoclonal expansion of EBV-negative NK cells highly secretory of IFN-γ as the most probable cause of HLH episode in a patient with Griscelli syndrome type-2. NK cell count recovered normal levels and phenotype after bone marrow transplantation from her HLA identical sister.

Research paper thumbnail of KIR Gene Mismatching and KIR/C Ligands in Liver Transplantation

Transplantation, 2013

Background. Killer immunoglobulin-like receptors (KIRs) bind human leukocyte antigen (HLA) class-... more Background. Killer immunoglobulin-like receptors (KIRs) bind human leukocyte antigen (HLA) class-I (HLA-I) ligands and regulate functions of natural killer cells and subsets of T cells. KIR/HLA-I interactions allow predicting natural killer cell alloreactivity in hematopoietic stem cell transplantation and in HLA-compatible kidney transplants, but its meaning in liver transplantation remains controversial. Methods. KIR and HLA genotypes were studied in 402 liver transplants, using sequence-specific oligonucleotides and primer methods. Recipients and donor KIRs, HLA-C genotypes, KIR gene mismatches (MMs) between recipientdonor pairs, and KIR/HLA-ligand combinations were analyzed in overall transplantations, in the acute rejection (AR; n=110) and non-AR (n=292) groups. Results. KIR gene MMs between recipients and donors, mainly in activating KIRs, and KIR2DL3 and KIR2DS1 of recipients in the presence of donor C2 ligands, significantly enhanced early AR rate (PG0.05), with KIR2DL3 + and KIR2DS1 + exhibiting a synergic effect in dependence of the donor C2 ligand number (W2=7.662, P=0.022). KIR2DL3, KIR2DS1, and also KIR2DS4 + significantly influenced short-term graft survival, with a benefit for transplantations combining KIR2DL3 + recipients and donors having C1 ligands (log rank, PG0.019 at 1 year; hazards ratio [HR], 0.321; 95% confidence interval [CI], 0.107Y0.962; P=0.042), whereas KIR2DS1 + and KIR2DS4 + recipients combined with donors lacking C1 ligands (C2/C2) exhibited a worse graft survival (log rank, P=0.035 at 6 months; HR, 7.713; 95% CI, 2.156Y27.369; P=0.002 for KIR2DS1 + ; and log rank, P=0.006 at 1 year; HR, 3.794; 95% CI, 1.267Y11.365; P=0.017 for KIR2DS4). Conclusions. This study shows that KIR gene-gene MMs increase AR and that KIRs/C ligands associated to AR and KIR2DS4 + /C ligands also influence short-term graft survival.

Research paper thumbnail of Balance of Circulating CD4+CD25+ and CD4+CD25+CTLA-4+ T Cells Could Play a Role in the Individual Commitment for the Short-Term Liver Graft Acceptance

Transplantation Journal, 2004

Aims: Chronic renal failure (CRF) is a recognized complication of organ transplantation and sever... more Aims: Chronic renal failure (CRF) is a recognized complication of organ transplantation and several risk factors there exist, linked both to patients and the procedure, which can favor its development. The aim of this study was to assess the incidence of post-transplantation CRF in a population of liver transplanted patients and to investigate the presence of possible risk factors for developing renal dysfunction. Methods: We performed a retrospective study on the liver-transplanted patients referring to liver transplantation ambulatory of "Tor Vergata" University of Rome and investigated the incidence of CRF and eventual need for renal replacement therapy (RRT). Furthermore, we searched for some possible risk factors for CRF development, such as systemic hypertension (SH), dyslipidemia, Diabetes Mellitus (DM), HBV and HCV status and calcyneurin inhibitors therapy. Results: From 1992 to today, 261 ortotopic liver transplantation have been performed at our Centre. In the post-transplantation period, 22 patients (8,4 %) developed chronic renal failure and were treated with standard intermittent hemodialysis (for a men time of 3 weeks). Among these, four male patients and one female subject have developed end stage renal disease (ESRD) and at present need chronic RRT. Further data about ESRD patients are reported in the Table below. One of them has died for cardiovascular complications during dialytic session. Among the remaining 17 patients, 5 subjects (29,5%) were HCV positive, 9/17 (52,9%) showed SH, 2/17 (11,8%) showed DM and 10/17 (58,8%) were treated with CsA. They partially recovered their renal function and are at present under conservative therapy. Conclusions: CRF proved to be a relatively common complication in our liver transplanted patients, confirming data reported in literature. Risk factors for developing renal dysfunction present in our patients are also cardiovascular risk factors and this could lead to an increase in mortality for cardiovascular pathology, particularly incident in uremic patients. It could be useful to pay attention to pretransplant renal dysfunction, modifiable cardiovascular risk factors and immunosuppressant protocol in order to avoid CRF onset in liver transplanted patients, thus obtaining a reduction of morbidity and mortality and of the costs for the National Sanitary System.

Research paper thumbnail of CD80 and CD86 Down-Modulation in Peripheal Blood Lymphocyte from Liver Recipients with a Good Graft Acceptance

Research paper thumbnail of Influence of human leukocyte antigen mismatching on rejection development and allograft survival in liver transplantation: Is the relevance of HLA-A locus matching being underestimated?

Transplant Immunology, 2012

The influence of HLA matching on liver transplant is still controversial, as studies have failed ... more The influence of HLA matching on liver transplant is still controversial, as studies have failed to demonstrate an adverse effect of HLA mismatching on transplant outcome. We examined the effect of HLA mismatching on transplant outcome in a series of 342 consecutive liver transplants (224 finally analyzed). HLA typing was performed by serological and molecular methods. HLA-A matching was associated with an increased chronic rejection incidence (P = 0.04). Indeed, HLA-A match also demonstrated a significant impact on allograft survival (P = 0.03), confirming previous observation concerning to rejection, as complete HLA-A mismatching favored a better liver transplant outcome. Analysis of HLA-A + B + DR matching also demonstrated a significant impact on graft survival (P b 0.05). Multivariate Cox regression analysis confirmed the effect of HLA-A and DPB1 matching as independent risk factors for graft loss. Another independent factor was a positive pre-transplant crossmatch. In conclusion, liver transplant outcome has not been found to be improved by HLA matching, however a poorer HLA compatibility favored a better graft survival and decreased rejection incidence, with a special relevance for HLA-A matching.

Research paper thumbnail of KIR gene variability in cutaneous malignant melanoma: influence of KIR2D/HLA-C pairings on disease susceptibility and prognosis

Immunogenetics, 2013

Natural killer and CD8(+) T cells are believed to be involved in the immune protection against me... more Natural killer and CD8(+) T cells are believed to be involved in the immune protection against melanoma. Their function may be regulated by a group of receptors defined as killer immunoglobulin-like receptors (KIRs) and their cognate HLA class I ligands. In this study, we analyzed the influence of KIR genes and KIR/HLA-I combinations on melanoma susceptibility and/or prognosis in a Spanish Caucasian population. For this purpose, KIR genotyping by PCR-SSP and HLA-C genotyping by reverse PCR-SSO were performed in 187 melanoma patients and 200 matched controls. We found a significantly low frequency of KIR2DL3 in nodular melanoma (NM) patients (P = 0.001) and in ulcerated melanoma patients (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001). Similarly, the KIR2DL3/C1 combination was significantly decreased in melanoma patients (Pc = 0.008) and in patients with sentinel lymph node (SLN) melanoma metastasis (Pc = 0.002). Multivariate logistic regression models showed that KIR2DL3 behaves as a protective marker for NM and ulcerated melanoma (P = 0.02, odds ratio (OR) = 0.14 and P = 0.04, OR = 0.28, respectively), whereas the KIR2DL3/C1 pair acts as a protective marker for melanoma (P = 0.017, OR = 0.54), particularly superficial spreading melanoma (P = 0.02, OR = 0.52), and SLN metastasis (P = 0.0004, OR = 0.14). In contrast, the KIR2DL3(-)/C1C2 genotype seems to be correlated with NM and ulceration. We also report that the KIR2DL1(+)/S1(-)/C2C2 genotype is associated with susceptibility to melanoma and SLN metastasis. Altogether, the study of KIR2D genes and HLA-C ligands may help in assessing cutaneous melanoma risk and prognosis.

Research paper thumbnail of Post-transplant increase in soluble human leukocyte antigen-G associated with non-severe cardiac allograft vasculopathy

Human Immunology, 2013

Cardiac allograft vasculopathy (CAV) is the single most important long-term limitation to heart t... more Cardiac allograft vasculopathy (CAV) is the single most important long-term limitation to heart transplantation. This study aimed to assess the value of monitoring soluble human leukocyte antigen-G (sHLA-G) during the first year post-transplantation to predict the severity of CAV, in 21 out of 77 heart recipients assessed by intravascular ultrasound (IVUS). Serum sHLA-G concentration increased after transplant in recipients free of severe CAV, but decreased in recipients suffering from severe CAV, significant differences between these two groups were found 6 to 12 months post-transplantation. The optimal value of the change in post-transplant sHLA-G for identifying severe CAV was P0.062%, which maximized sensitivity (80%) and specificity (100%). Importantly, increases in post-transplant sHLA-G were inversely associated with severe CAV, but directly associated with human cytomegalovirus reactivation. In addition, recipients presenting non-severe CAV or an increased sHLA-G post-transplantation, showed higher numbers of CD8 + CD28 À T cells and a down-modulation of CD28 on CD4 + lymphocytes, which typically identifies CD8 + regulatory T cells and anergic/tolerogenic T helper cells, respectively. In conclusion, quantification of sHLA-G might offer a complementary non-invasive method for identifying recipients at risk of more severe CAV and who might benefit from earlier preventive therapies, although these results need to be confirmed in larger series.

Research paper thumbnail of LILRA6 copy number variation correlates with susceptibility to atopic dermatitis

Immunogenetics, Jan 22, 2016

Leukocyte immunoglobulin-like receptors (LILR) are expressed mostly on myelomonocytic cells where... more Leukocyte immunoglobulin-like receptors (LILR) are expressed mostly on myelomonocytic cells where they are mediators of immunological tolerance. Two LILR genes, LILRA3 and LILRA6, exhibit marked copy number variation. We assessed the contribution of these genes to atopic dermatitis (AD) by analysing transmission in 378 AD families. The data indicated that copies of LILRA6 were over-transmitted to affected patients. They are consistent with a contribution of LILR genes to AD. They could affect the equilibrium between activating and inhibitory signals in the immune response.

Research paper thumbnail of SpeS: A Novel Superantigen and Its Potential as a Vaccine Adjuvant against Strangles

International Journal of Molecular Sciences

Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspec... more Bacterial superantigens (sAgs) are powerful activators of the immune response that trigger unspecific T cell responses accompanied by the release of proinflammatory cytokines. Streptococcus equi (S. equi) and Streptococcus zooepidemicus (S. zooepidemicus) produce sAgs that play an important role in their ability to cause disease. Strangles, caused by S. equi, is one of the most common infectious diseases of horses worldwide. Here, we report the identification of a new sAg of S. zooepidemicus, SpeS, and show that mutation of the putative T cell receptor (TCR)-binding motif (YAY to IAY) abrogated TCR-binding, whilst maintaining interaction with major histocompatibility complex (MHC) class II molecules. The fusion of SpeS and SpeSY39I to six S. equi surface proteins using two different peptide linkers was conducted to determine if MHC class II-binding properties were maintained. Proliferation assays, qPCR and flow cytometry analysis showed that SpeSY39I and its fusion proteins induced ...