Judith Endres - Academia.edu (original) (raw)

Papers by Judith Endres

Research paper thumbnail of Expression and Characterization of a Novel CD6 Ligand in Cells Derived from Joint and Epithelial Tissues

The Journal of Immunology, 2004

Research paper thumbnail of Synovial phenotypes in rheumatoid arthritis correlate with response to biologic therapeutics

Arthritis Research & Therapy, 2014

Introduction: Rheumatoid arthritis (RA) is a complex and clinically heterogeneous autoimmune dise... more Introduction: Rheumatoid arthritis (RA) is a complex and clinically heterogeneous autoimmune disease. Currently, the relationship between pathogenic molecular drivers of disease in RA and therapeutic response is poorly understood. Methods: We analyzed synovial tissue samples from two RA cohorts of 49 and 20 patients using a combination of global gene expression, histologic and cellular analyses, and analysis of gene expression data from two further publicly available RA cohorts. To identify candidate serum biomarkers that correspond to differential synovial biology and clinical response to targeted therapies, we performed pre-treatment biomarker analysis compared with therapeutic outcome at week 24 in serum samples from 198 patients from the ADACTA (ADalimumab ACTemrA) phase 4 trial of tocilizumab (anti-IL-6R) monotherapy versus adalimumab (anti-TNFα) monotherapy. Results: We documented evidence for four major phenotypes of RA synoviumlymphoid, myeloid, low inflammatory, and fibroid -each with distinct underlying gene expression signatures. We observed that baseline synovial myeloid, but not lymphoid, gene signature expression was higher in patients with good compared with poor European league against rheumatism (EULAR) clinical response to anti-TNFα therapy at week 16 (P =0.011). We observed that high baseline serum soluble intercellular adhesion molecule 1 (sICAM1), associated with the myeloid phenotype, and high serum C-X-C motif chemokine 13 (CXCL13), associated with the lymphoid phenotype, had differential relationships with clinical response to anti-TNFα compared with anti-IL6R treatment. sICAM1-high/ CXCL13-low patients showed the highest week 24 American College of Rheumatology (ACR) 50 response rate to anti-TNFα treatment as compared with sICAM1-low/CXCL13-high patients (42% versus 13%, respectively, P =0.05) while anti-IL-6R patients showed the opposite relationship with these biomarker subgroups (ACR50 20% versus 69%, P =0.004).

Research paper thumbnail of Expression and Function of Aminopeptidase N/CD13 Produced by Fibroblast-like Synoviocytes in Rheumatoid Arthritis: Role of CD13 in Chemotaxis of Cytokine-Activated T Cells Independent of Enzymatic Activity

Arthritis & rheumatology (Hoboken, N.J.), 2015

Aminopeptidase N/CD13 (EC 3.4.11.2) is a metalloproteinase expressed by fibroblast-like synoviocy... more Aminopeptidase N/CD13 (EC 3.4.11.2) is a metalloproteinase expressed by fibroblast-like synoviocytes (FLS). It has been suggested that CD13 can act chemotactically for T cells in rheumatoid arthritis (RA). We undertook this study to measure CD13 in vivo and in vitro in RA samples and to determine whether CD13 could play a role in the homing of T cells to the RA joint. Interleukin-17-treated FLS were used to immunize mice, from which a novel anti-human CD13 monoclonal antibody (mAb), 591.1D7.34, was developed. The mAb 591.1D7.34 and a second anti-CD13 mAb, WM15, were used to develop a novel enzyme-linked immunosorbent assay (ELISA) for CD13, and CD13 enzymatic activity was measured in parallel. Chemotaxis of cytokine-activated T cells was measured by a chemotaxis-under-agarose assay. We detected substantial amounts of CD13 in synovial fluid (SF), sera, FLS lysates, and culture supernatants by ELISA, with a significant increase in CD13 in RA SF when compared to osteoarthritis SF. CD13...

Research paper thumbnail of Xenogeneic cells and superantigen induce human T-cell activation in the absence of T-cell recognition of xenoantigen

The Journal of laboratory and clinical medicine, 2003

The extent of interaction between human T-lymphocytes and xenogeneic antigen-presenting cells (AP... more The extent of interaction between human T-lymphocytes and xenogeneic antigen-presenting cells (APCs) is species-dependent. A successful interaction requires high-affinity receptor-ligand pairing across species and recognition of antigens presented by foreign major histocompatibility complex (MHC). A deficient human T-lymphocyte response to xenogeneic cells is likely the result of a defect in these interactions. However, the requirements for a T-cell response to superantigen (SAg) may differ from those of other T-cell responses. Using irradiated murine splenocytes, which are believed to be incapable of eliciting human T-cell responses, and porcine aortic endothelial cells (PAECs) as the APC populations, we studied the human T-lymphocyte response to antigens presented by these cells. Direct proliferation of human T-lymphocytes to SAg presented by murine APCs was demonstrated; it was blocked by anti-human LFA-1 and anti-murine MHC class II but not by anti-human MHC class II. PAECs also...

Research paper thumbnail of The roles of IFN-γ versus IL-17 in pathogenic effects of human Th17 cells on synovial fibroblasts

Modern Rheumatology, 2013

Th17 cells, while indispensable in host defense, may play pathogenic roles in many autoimmune dis... more Th17 cells, while indispensable in host defense, may play pathogenic roles in many autoimmune diseases, including rheumatoid arthritis (RA). However, the mechanisms by which human Th17 cells drive autoimmunity have not been fully defined. We assessed the potential of the human Th17 CD4 T cell subset to induce expression of cell-cell interaction molecules and inflammatory mediators by fibroblast-like synoviocytes (FLS), and the roles of IFN-γ and IL-17 in these interactions. Th1 or Th17 cells were induced from healthy adult donor CD4 T cells and were co-cultured with FLS for 48 h with/without neutralization of IFN-γ, IL-17A, or both. Alternatively, FLS were treated only with IFN-γ or IL-17 for 48 h. FLS expression of CD40, CD54, and MHC-II, as well as IL-6 and IL-8 secretion, were assessed by surface staining followed by flow cytometry and ELISA, respectively. Both Th1 and Th17 cells secreted IL-17 as well as IFN-γ, although IFN-γ production was much greater from Th1 cells. FLS expression of CD40, CD54, and MHC-II significantly increased upon co-culture with Th1 cells, while Th17 cells increased only the percentage of FLS that were CD54+. Both T cell subsets induced IL-6 and IL-8 secretion by RA FLS. Neutralization of IL-17A did not reduce FLS expression of CD40, MHC-II, or CD54, but did inhibit IL-6 and IL-8 secretion. Although IFN-γ was a weak inducer of IL-6 secretion and significantly inhibited IL-8 secretion from FLS when used as a single stimulus, neutralization of IFN-γ inhibited the secretion of both cytokines in Th17/FLS co-cultures with RA but not OA FLS. FLS cell-cell interaction molecules and soluble inflammatory mediators are differentially regulated by IFN-γ and IL-17. The effects of IFN-γ may depend in part on the particular milieu of other co-existing cytokines and its potential to induce cell-cell interactions. The potential benefit of therapeutic neutralization of either IL-17 or IFN-γ could depend on the relative proportions of these cytokines in the synovial compartment of an RA patient.

Research paper thumbnail of Sensitivity and Resistance to Regulation by IL-4 during Th17 Maturation

The Journal of Immunology, 2011

Th17 cells are highly pathogenic in a variety of immune-mediated diseases, and a thorough underst... more Th17 cells are highly pathogenic in a variety of immune-mediated diseases, and a thorough understanding of the mechanisms of cytokine-mediated suppression of Th17 cells has great therapeutic potential. In this article, we characterize the regulation of both in vitro-and in vivo-derived Th17 cells by IL-4. We demonstrate that IL-4 suppresses reactivation of committed Th17 cells, even in the presence of TGF-b, IL-6, and IL-23. Downregulation of IL-17 by IL-4 is dependent on STAT6 and mediated by inhibition of STAT3 binding at the Il17a promoter. Although Th1 cytokines were shown to induce IFN-g expression by Th17 cells, IL-4 does not induce a Th2 phenotype in Th17 cells. Suppression by IL-4 is stable and long-lived when applied to immature Th17 cells, but cells that have undergone multiple rounds of stimulation, either in vivo during a Th17-mediated inflammatory disease, or in vitro, become resistant to suppression by IL-4 and lose the ability to signal through IL-4R. Thus, although IL-4 is a potent suppressor of the Th17 genetic program at early stages after differentiation, prolonged stimulation renders Th17 cells impervious to regulatory cytokines.

Research paper thumbnail of Interactions of T Cells with Fibroblast-Like Synoviocytes: Role of the B7 Family Costimulatory Ligand B7-H3

The Journal of Immunology, 2008

Research paper thumbnail of Immunocompetent Properties of Human Osteoblasts: Interactions With T Lymphocytes

Journal of Bone and Mineral Research, 2005

We sought to determine whether osteoblasts (OBs) can serve as accessory cells (ACs) for T-cell ac... more We sought to determine whether osteoblasts (OBs) can serve as accessory cells (ACs) for T-cell activation and whether T cells directly activate OB production of IL-6, using primary human OBs (NHOst), the transformed fetal osteoblast line hFOB1.19, and an osteosarcoma line SaOS-2. Robust, bidirectional activating interactions were shown using each of these three human ostoblast lines.

Research paper thumbnail of CD6: expression during development, apoptosis and selection of human and mouse thymocytes

International Immunology, 2002

CD6, a 130-kDa surface glycoprotein, is expressed primarily on cells of T lineage. A co-stimulato... more CD6, a 130-kDa surface glycoprotein, is expressed primarily on cells of T lineage. A co-stimulatory role for CD6 in mature T cells has been shown, but the function of CD6 during thymocyte development is unknown. Since CD6 ligands are expressed on thymic epithelium, their interactions with CD6 could be important in thymic selection. In this report we show that CD6 is developmentally regulated in human and mouse thymocytes, and further demonstrate that increase in the level of CD6 expression correlates with expression of the selection marker CD69. We also show that activation via CD2 induces CD6 expression on mature human thymocytes and on a subset of immature human thymocytes that are resistant to apoptosis. In human and mouse thymocytes that express heterogeneous TCR, CD6 increases occur as double-positive thymocytes are selected to a single-positive stage. In contrast, in thymocytes from TCR transgenic mice, CD6 is barely increased following selection, suggesting that as functional avidity increases, requirements for CD6-dependent co-stimulation decrease. Taken together, these results indicate that during thymic development CD6-dependent signals may contribute both to thymocyte survival, and to the overall functional avidity of selection in both man and mouse.

Research paper thumbnail of Dendritic cells genetically engineered to express IL-4 exhibit enhanced IL-12p70 production in response to CD40 ligation and accelerate organ allograft rejection

Gene Therapy, 2003

Dendritic cells (DCs) are professional APCs that have a unique capacity to initiate primary immun... more Dendritic cells (DCs) are professional APCs that have a unique capacity to initiate primary immune responses, including tolerogenic responses. We have genetically engineered bone marrow-derived DCs to express the immunosuppressive cytokine IL-10 and tested the ability of these cells to control experimental asthma. A single intratracheal injection of OVA-pulsed IL-10-transduced DCs (OVA-IL-10-DCs) to naive mice before OVA sensitization and challenge prevented all of the cardinal features of airway allergy, namely, eosinophilic airway inflammation, airway hyperreactivity, and production of mucus, Ag-specific Igs, and IL-4. OVA-IL-10-DCs also reversed established experimental asthma and had long-lasting and Agspecific effects. We furthermore showed, by using IL-10-deficient mice, that host IL-10 is required for mediating the immunomodulatory effects of OVA-IL-10-DCs and demonstrated a significant increase in the percentage of OVA-specific CD4 ؉ CD25 ؉ Foxp3 ؉ IL-10 ؉ regulatory T cells in the mediastinal lymph nodes of OVA-IL-10-DC-injected mice. Finally, adoptive transfer of CD4 ؉ mediastinal lymph node T cells from mice injected with OVA-IL-10-DCs protected OVA-sensitized recipients from airway eosinophilia upon OVA provocation. Our study describes a promising strategy to induce long-lasting Ag-specific tolerance in airway allergy.

Research paper thumbnail of A polymorphism in the interleukin-4 receptor affects the ability of interleukin-4 to regulate Th17 cells: a possible immunoregulatory mechanism for genetic control of the severity of rheumatoid arthritis

Arthritis Research & Therapy, 2011

Introduction: Rheumatoid arthritis (RA) is now suspected to be driven by pathogenic Th17 cells th... more Introduction: Rheumatoid arthritis (RA) is now suspected to be driven by pathogenic Th17 cells that secrete interleukin (IL)-17 and can be regulated by IL-4. A single-nucleotide polymorphism (SNP), I50V, in the coding region of the human IL-4 receptor (IL-4R) is associated with rapid development of erosive disease in RA. The present study was undertaken to determine whether this SNP renders the IL-4R less able to transduce signals that regulate IL-17 production. Methods: Peripheral blood mononuclear cells were activated under Th17-stimulating conditions in the presence or absence of IL-4, and IL-17 production was measured by both enzyme-linked immunosorbent assay (ELISA) and flow cytometry. Serum IL-17 was also measured by ELISA. Paired comparisons were performed using the two-tailed ttest. IL-4 receptor gene alleles were determined by polymerase chain reaction. Results: In healthy individuals, IL-4 significantly inhibited IL-17 production by cells from subjects with the I/I genotype (P = 0.0079) and the I/V genotype (P = 0.013), but not the V/V genotype (P > 0.05). In a cross-sectional sample of patients with established RA, the magnitude of the in vitro effect of IL-4 was lower and was not associated with a specific IL-4R allele. Serum IL-17 levels were higher in RA patients than in healthy individuals, as was the percentage of CD4 + cells that produced IL-17. Conclusions: These results indicate that an inherited polymorphism of the IL-4R controls the ability of the human immune system to regulate the magnitude of IL-17 production. However, in established RA, this pattern may be altered, possibly due to secondary effects of both RA itself as well as immunomodulatory medications. Ineffective control of Th17 immune responses is a potential mechanism to explain why IL-4R is an important severity gene in RA, but this issue will require careful study of a cohort of new-onset RA patients.

Research paper thumbnail of Regulation of pathogenic IL-17 responses in collagen-induced arthritis: roles of endogenous interferon-gamma and IL-4

Arthritis Research & Therapy, 2009

Introduction Interleukin (IL)-17 plays an important role in the pathogenesis of rheumatoid arthri... more Introduction Interleukin (IL)-17 plays an important role in the pathogenesis of rheumatoid arthritis and the mouse model collagen-induced arthritis (CIA). Interferon(IFN)-γ and IL-4 have been shown to suppress Th17 development in vitro, but their potential immunoregulatory roles in vivo are uncertain. The goals of this study were to determine the relationship between Th17 responses and disease severity in CIA and to assess regulation of IL-17 by endogenous IFN-γ and IL-4.

Research paper thumbnail of Presentation of arthritogenic peptide to antigen-specific T cells by fibroblast-like synoviocytes

Arthritis & Rheumatism, 2007

Methods. Human class II major histocompatibility complex (MHC)-typed FLS were used as APCs for mu... more Methods. Human class II major histocompatibility complex (MHC)-typed FLS were used as APCs for murine class II MHC-restricted CD4 T cell hybridomas.

Research paper thumbnail of Interleukin-17 as a molecular target in immune-mediated arthritis: Immunoregulatory properties of genetically modified murine dendritic cells that secrete interleukin-4

Arthritis & Rheumatism, 2007

Our previous studies have shown that murine dendritic cells (DCs) genetically modified to express... more Our previous studies have shown that murine dendritic cells (DCs) genetically modified to express interleukin-4 (IL-4) reduce the incidence and severity of murine collagen-induced arthritis. The present studies were performed to assess the immunoregulatory mechanisms underlying this response, by assessing the effects of IL-4 DCs on cytokine production by subsets of T helper cells. Male DBA mice ages 6-8 weeks old were immunized with type II collagen. Splenic T cells obtained during the initiation phase and the end stage of arthritis were cultured with IL-4 DCs or untransduced DCs in the presence of collagen rechallenge. Interferon-gamma (IFNgamma) and IL-17 responses were measured. Antibodies to IL-4, IL-12, and IL-23, and recombinant IL-4, IL-12, and IL-23 were used to further study the regulation of T cell cytokine production by IL-4 DCs. Splenic T cells obtained during the initiation phase of arthritis produced less IL-17 when cultured in the presence of IL-4 DCs, despite their production of increased quantities of other proinflammatory cytokines (IFNgamma and tumor necrosis factor). T cell IL-17 production after collagen rechallenge was not inhibited by a lack of IL-23, since IL-4-mediated suppression of IL-17 was not reconstituted by IL-23, an otherwise potent inducer of IL-17 production by T cells. Although IL-4 DCs can produce increased quantities of IL-12 and IFNgamma, suppression of IL-17 production by IL-4 DCs was independent of both. While IL-17 production by T cells obtained during the initiation phase of arthritis was regulated by IL-4 DCs, IL-17 production by T cells obtained during end-stage arthritis was not altered. Our data suggest that IL-4 DCs exert a therapeutic effect on collagen-induced arthritis by targeting IL-17. IL-17 suppression by IL-4 DCs is robust and is not reversed by IL-23. Timing might be important in IL-17-targeted therapy, since IL-17 production by T cells obtained during end-stage arthritis did not respond to suppression by IL-4 DCs.

Research paper thumbnail of Evidence for the expression of a second CD6 ligand by synovial fibroblasts

Arthritis & Rheumatism, 2000

Objective. CD6, a cell surface glycoprotein expressed primarily on T cells, may function as a cos... more Objective. CD6, a cell surface glycoprotein expressed primarily on T cells, may function as a costimulatory molecule and may play a role in autoreactive immune responses. Recently, a CD6 ligand termed CD166 (previously known as activated leukocyte cell adhesion molecule [ALCAM]) has been identified and shown to be expressed on activated T cells, B cells, thymic epithelium, keratinocytes, and in rheumatoid arthritis synovial tissue. However, the results of functional studies have suggested the existence of a second CD6 ligand. The present study was undertaken to seek evidence for a second CD6 ligand on cultured synovial fibroblasts.

Research paper thumbnail of Systemic Toxicity Following Administration of Sirolimus (Formerly Rapamycin) for Psoriasis

Archives of Dermatology, 1999

Background: Sirolimus (formerly rapamycin) is an im- munosuppressive agent that interferes with T... more Background: Sirolimus (formerly rapamycin) is an im- munosuppressive agent that interferes with T-cell acti- vation. After 2 individuals with psoriasis developed a cap- illary leak syndrome following treatment with oral sirolimus, lesional skin cells and activated peripheral blood cells were analyzed for induction of apoptosis. Observations: A keratome skin specimen from 1 patient with sirolimus-induced capillary leak syndrome had a

Research paper thumbnail of Molecular Interactions between T Cells and Fibroblast-Like Synoviocytes

The American Journal of Pathology, 2007

Tck also readily activated FLS to produce interleukin IL-6 and IL-8 in a cell contact-dependent m... more Tck also readily activated FLS to produce interleukin IL-6 and IL-8 in a cell contact-dependent manner that was enhanced by exogenous IL-17. Although LFA-1 and ICAM-1 co-localized at the Tck-FLS synapse, blocking the LFA-1/ICAM-1 interaction did not substantially inhibit Tck effector function. However, antibody blocking of membrane tumor necrosis factor (TNF)-␣ on the Tck surface did inhibit FLS cytokine production, thus illustrating a novel mechanism for involvement of TNF-␣ in cell-cell interactions in RA synovium and for the effectiveness of TNF-␣ blockade in the treatment of RA. (Am J

Research paper thumbnail of Activation of Synovial Fibroblasts Effector Function of Resting T Cells

Research paper thumbnail of Expression and Characterization of a Novel CD6 Ligand in Cells Derived from Joint and Epithelial Tissues

The Journal of Immunology, 2004

Research paper thumbnail of Synovial phenotypes in rheumatoid arthritis correlate with response to biologic therapeutics

Arthritis Research & Therapy, 2014

Introduction: Rheumatoid arthritis (RA) is a complex and clinically heterogeneous autoimmune dise... more Introduction: Rheumatoid arthritis (RA) is a complex and clinically heterogeneous autoimmune disease. Currently, the relationship between pathogenic molecular drivers of disease in RA and therapeutic response is poorly understood. Methods: We analyzed synovial tissue samples from two RA cohorts of 49 and 20 patients using a combination of global gene expression, histologic and cellular analyses, and analysis of gene expression data from two further publicly available RA cohorts. To identify candidate serum biomarkers that correspond to differential synovial biology and clinical response to targeted therapies, we performed pre-treatment biomarker analysis compared with therapeutic outcome at week 24 in serum samples from 198 patients from the ADACTA (ADalimumab ACTemrA) phase 4 trial of tocilizumab (anti-IL-6R) monotherapy versus adalimumab (anti-TNFα) monotherapy. Results: We documented evidence for four major phenotypes of RA synoviumlymphoid, myeloid, low inflammatory, and fibroid -each with distinct underlying gene expression signatures. We observed that baseline synovial myeloid, but not lymphoid, gene signature expression was higher in patients with good compared with poor European league against rheumatism (EULAR) clinical response to anti-TNFα therapy at week 16 (P =0.011). We observed that high baseline serum soluble intercellular adhesion molecule 1 (sICAM1), associated with the myeloid phenotype, and high serum C-X-C motif chemokine 13 (CXCL13), associated with the lymphoid phenotype, had differential relationships with clinical response to anti-TNFα compared with anti-IL6R treatment. sICAM1-high/ CXCL13-low patients showed the highest week 24 American College of Rheumatology (ACR) 50 response rate to anti-TNFα treatment as compared with sICAM1-low/CXCL13-high patients (42% versus 13%, respectively, P =0.05) while anti-IL-6R patients showed the opposite relationship with these biomarker subgroups (ACR50 20% versus 69%, P =0.004).

Research paper thumbnail of Expression and Function of Aminopeptidase N/CD13 Produced by Fibroblast-like Synoviocytes in Rheumatoid Arthritis: Role of CD13 in Chemotaxis of Cytokine-Activated T Cells Independent of Enzymatic Activity

Arthritis & rheumatology (Hoboken, N.J.), 2015

Aminopeptidase N/CD13 (EC 3.4.11.2) is a metalloproteinase expressed by fibroblast-like synoviocy... more Aminopeptidase N/CD13 (EC 3.4.11.2) is a metalloproteinase expressed by fibroblast-like synoviocytes (FLS). It has been suggested that CD13 can act chemotactically for T cells in rheumatoid arthritis (RA). We undertook this study to measure CD13 in vivo and in vitro in RA samples and to determine whether CD13 could play a role in the homing of T cells to the RA joint. Interleukin-17-treated FLS were used to immunize mice, from which a novel anti-human CD13 monoclonal antibody (mAb), 591.1D7.34, was developed. The mAb 591.1D7.34 and a second anti-CD13 mAb, WM15, were used to develop a novel enzyme-linked immunosorbent assay (ELISA) for CD13, and CD13 enzymatic activity was measured in parallel. Chemotaxis of cytokine-activated T cells was measured by a chemotaxis-under-agarose assay. We detected substantial amounts of CD13 in synovial fluid (SF), sera, FLS lysates, and culture supernatants by ELISA, with a significant increase in CD13 in RA SF when compared to osteoarthritis SF. CD13...

Research paper thumbnail of Xenogeneic cells and superantigen induce human T-cell activation in the absence of T-cell recognition of xenoantigen

The Journal of laboratory and clinical medicine, 2003

The extent of interaction between human T-lymphocytes and xenogeneic antigen-presenting cells (AP... more The extent of interaction between human T-lymphocytes and xenogeneic antigen-presenting cells (APCs) is species-dependent. A successful interaction requires high-affinity receptor-ligand pairing across species and recognition of antigens presented by foreign major histocompatibility complex (MHC). A deficient human T-lymphocyte response to xenogeneic cells is likely the result of a defect in these interactions. However, the requirements for a T-cell response to superantigen (SAg) may differ from those of other T-cell responses. Using irradiated murine splenocytes, which are believed to be incapable of eliciting human T-cell responses, and porcine aortic endothelial cells (PAECs) as the APC populations, we studied the human T-lymphocyte response to antigens presented by these cells. Direct proliferation of human T-lymphocytes to SAg presented by murine APCs was demonstrated; it was blocked by anti-human LFA-1 and anti-murine MHC class II but not by anti-human MHC class II. PAECs also...

Research paper thumbnail of The roles of IFN-γ versus IL-17 in pathogenic effects of human Th17 cells on synovial fibroblasts

Modern Rheumatology, 2013

Th17 cells, while indispensable in host defense, may play pathogenic roles in many autoimmune dis... more Th17 cells, while indispensable in host defense, may play pathogenic roles in many autoimmune diseases, including rheumatoid arthritis (RA). However, the mechanisms by which human Th17 cells drive autoimmunity have not been fully defined. We assessed the potential of the human Th17 CD4 T cell subset to induce expression of cell-cell interaction molecules and inflammatory mediators by fibroblast-like synoviocytes (FLS), and the roles of IFN-γ and IL-17 in these interactions. Th1 or Th17 cells were induced from healthy adult donor CD4 T cells and were co-cultured with FLS for 48 h with/without neutralization of IFN-γ, IL-17A, or both. Alternatively, FLS were treated only with IFN-γ or IL-17 for 48 h. FLS expression of CD40, CD54, and MHC-II, as well as IL-6 and IL-8 secretion, were assessed by surface staining followed by flow cytometry and ELISA, respectively. Both Th1 and Th17 cells secreted IL-17 as well as IFN-γ, although IFN-γ production was much greater from Th1 cells. FLS expression of CD40, CD54, and MHC-II significantly increased upon co-culture with Th1 cells, while Th17 cells increased only the percentage of FLS that were CD54+. Both T cell subsets induced IL-6 and IL-8 secretion by RA FLS. Neutralization of IL-17A did not reduce FLS expression of CD40, MHC-II, or CD54, but did inhibit IL-6 and IL-8 secretion. Although IFN-γ was a weak inducer of IL-6 secretion and significantly inhibited IL-8 secretion from FLS when used as a single stimulus, neutralization of IFN-γ inhibited the secretion of both cytokines in Th17/FLS co-cultures with RA but not OA FLS. FLS cell-cell interaction molecules and soluble inflammatory mediators are differentially regulated by IFN-γ and IL-17. The effects of IFN-γ may depend in part on the particular milieu of other co-existing cytokines and its potential to induce cell-cell interactions. The potential benefit of therapeutic neutralization of either IL-17 or IFN-γ could depend on the relative proportions of these cytokines in the synovial compartment of an RA patient.

Research paper thumbnail of Sensitivity and Resistance to Regulation by IL-4 during Th17 Maturation

The Journal of Immunology, 2011

Th17 cells are highly pathogenic in a variety of immune-mediated diseases, and a thorough underst... more Th17 cells are highly pathogenic in a variety of immune-mediated diseases, and a thorough understanding of the mechanisms of cytokine-mediated suppression of Th17 cells has great therapeutic potential. In this article, we characterize the regulation of both in vitro-and in vivo-derived Th17 cells by IL-4. We demonstrate that IL-4 suppresses reactivation of committed Th17 cells, even in the presence of TGF-b, IL-6, and IL-23. Downregulation of IL-17 by IL-4 is dependent on STAT6 and mediated by inhibition of STAT3 binding at the Il17a promoter. Although Th1 cytokines were shown to induce IFN-g expression by Th17 cells, IL-4 does not induce a Th2 phenotype in Th17 cells. Suppression by IL-4 is stable and long-lived when applied to immature Th17 cells, but cells that have undergone multiple rounds of stimulation, either in vivo during a Th17-mediated inflammatory disease, or in vitro, become resistant to suppression by IL-4 and lose the ability to signal through IL-4R. Thus, although IL-4 is a potent suppressor of the Th17 genetic program at early stages after differentiation, prolonged stimulation renders Th17 cells impervious to regulatory cytokines.

Research paper thumbnail of Interactions of T Cells with Fibroblast-Like Synoviocytes: Role of the B7 Family Costimulatory Ligand B7-H3

The Journal of Immunology, 2008

Research paper thumbnail of Immunocompetent Properties of Human Osteoblasts: Interactions With T Lymphocytes

Journal of Bone and Mineral Research, 2005

We sought to determine whether osteoblasts (OBs) can serve as accessory cells (ACs) for T-cell ac... more We sought to determine whether osteoblasts (OBs) can serve as accessory cells (ACs) for T-cell activation and whether T cells directly activate OB production of IL-6, using primary human OBs (NHOst), the transformed fetal osteoblast line hFOB1.19, and an osteosarcoma line SaOS-2. Robust, bidirectional activating interactions were shown using each of these three human ostoblast lines.

Research paper thumbnail of CD6: expression during development, apoptosis and selection of human and mouse thymocytes

International Immunology, 2002

CD6, a 130-kDa surface glycoprotein, is expressed primarily on cells of T lineage. A co-stimulato... more CD6, a 130-kDa surface glycoprotein, is expressed primarily on cells of T lineage. A co-stimulatory role for CD6 in mature T cells has been shown, but the function of CD6 during thymocyte development is unknown. Since CD6 ligands are expressed on thymic epithelium, their interactions with CD6 could be important in thymic selection. In this report we show that CD6 is developmentally regulated in human and mouse thymocytes, and further demonstrate that increase in the level of CD6 expression correlates with expression of the selection marker CD69. We also show that activation via CD2 induces CD6 expression on mature human thymocytes and on a subset of immature human thymocytes that are resistant to apoptosis. In human and mouse thymocytes that express heterogeneous TCR, CD6 increases occur as double-positive thymocytes are selected to a single-positive stage. In contrast, in thymocytes from TCR transgenic mice, CD6 is barely increased following selection, suggesting that as functional avidity increases, requirements for CD6-dependent co-stimulation decrease. Taken together, these results indicate that during thymic development CD6-dependent signals may contribute both to thymocyte survival, and to the overall functional avidity of selection in both man and mouse.

Research paper thumbnail of Dendritic cells genetically engineered to express IL-4 exhibit enhanced IL-12p70 production in response to CD40 ligation and accelerate organ allograft rejection

Gene Therapy, 2003

Dendritic cells (DCs) are professional APCs that have a unique capacity to initiate primary immun... more Dendritic cells (DCs) are professional APCs that have a unique capacity to initiate primary immune responses, including tolerogenic responses. We have genetically engineered bone marrow-derived DCs to express the immunosuppressive cytokine IL-10 and tested the ability of these cells to control experimental asthma. A single intratracheal injection of OVA-pulsed IL-10-transduced DCs (OVA-IL-10-DCs) to naive mice before OVA sensitization and challenge prevented all of the cardinal features of airway allergy, namely, eosinophilic airway inflammation, airway hyperreactivity, and production of mucus, Ag-specific Igs, and IL-4. OVA-IL-10-DCs also reversed established experimental asthma and had long-lasting and Agspecific effects. We furthermore showed, by using IL-10-deficient mice, that host IL-10 is required for mediating the immunomodulatory effects of OVA-IL-10-DCs and demonstrated a significant increase in the percentage of OVA-specific CD4 ؉ CD25 ؉ Foxp3 ؉ IL-10 ؉ regulatory T cells in the mediastinal lymph nodes of OVA-IL-10-DC-injected mice. Finally, adoptive transfer of CD4 ؉ mediastinal lymph node T cells from mice injected with OVA-IL-10-DCs protected OVA-sensitized recipients from airway eosinophilia upon OVA provocation. Our study describes a promising strategy to induce long-lasting Ag-specific tolerance in airway allergy.

Research paper thumbnail of A polymorphism in the interleukin-4 receptor affects the ability of interleukin-4 to regulate Th17 cells: a possible immunoregulatory mechanism for genetic control of the severity of rheumatoid arthritis

Arthritis Research & Therapy, 2011

Introduction: Rheumatoid arthritis (RA) is now suspected to be driven by pathogenic Th17 cells th... more Introduction: Rheumatoid arthritis (RA) is now suspected to be driven by pathogenic Th17 cells that secrete interleukin (IL)-17 and can be regulated by IL-4. A single-nucleotide polymorphism (SNP), I50V, in the coding region of the human IL-4 receptor (IL-4R) is associated with rapid development of erosive disease in RA. The present study was undertaken to determine whether this SNP renders the IL-4R less able to transduce signals that regulate IL-17 production. Methods: Peripheral blood mononuclear cells were activated under Th17-stimulating conditions in the presence or absence of IL-4, and IL-17 production was measured by both enzyme-linked immunosorbent assay (ELISA) and flow cytometry. Serum IL-17 was also measured by ELISA. Paired comparisons were performed using the two-tailed ttest. IL-4 receptor gene alleles were determined by polymerase chain reaction. Results: In healthy individuals, IL-4 significantly inhibited IL-17 production by cells from subjects with the I/I genotype (P = 0.0079) and the I/V genotype (P = 0.013), but not the V/V genotype (P > 0.05). In a cross-sectional sample of patients with established RA, the magnitude of the in vitro effect of IL-4 was lower and was not associated with a specific IL-4R allele. Serum IL-17 levels were higher in RA patients than in healthy individuals, as was the percentage of CD4 + cells that produced IL-17. Conclusions: These results indicate that an inherited polymorphism of the IL-4R controls the ability of the human immune system to regulate the magnitude of IL-17 production. However, in established RA, this pattern may be altered, possibly due to secondary effects of both RA itself as well as immunomodulatory medications. Ineffective control of Th17 immune responses is a potential mechanism to explain why IL-4R is an important severity gene in RA, but this issue will require careful study of a cohort of new-onset RA patients.

Research paper thumbnail of Regulation of pathogenic IL-17 responses in collagen-induced arthritis: roles of endogenous interferon-gamma and IL-4

Arthritis Research & Therapy, 2009

Introduction Interleukin (IL)-17 plays an important role in the pathogenesis of rheumatoid arthri... more Introduction Interleukin (IL)-17 plays an important role in the pathogenesis of rheumatoid arthritis and the mouse model collagen-induced arthritis (CIA). Interferon(IFN)-γ and IL-4 have been shown to suppress Th17 development in vitro, but their potential immunoregulatory roles in vivo are uncertain. The goals of this study were to determine the relationship between Th17 responses and disease severity in CIA and to assess regulation of IL-17 by endogenous IFN-γ and IL-4.

Research paper thumbnail of Presentation of arthritogenic peptide to antigen-specific T cells by fibroblast-like synoviocytes

Arthritis & Rheumatism, 2007

Methods. Human class II major histocompatibility complex (MHC)-typed FLS were used as APCs for mu... more Methods. Human class II major histocompatibility complex (MHC)-typed FLS were used as APCs for murine class II MHC-restricted CD4 T cell hybridomas.

Research paper thumbnail of Interleukin-17 as a molecular target in immune-mediated arthritis: Immunoregulatory properties of genetically modified murine dendritic cells that secrete interleukin-4

Arthritis & Rheumatism, 2007

Our previous studies have shown that murine dendritic cells (DCs) genetically modified to express... more Our previous studies have shown that murine dendritic cells (DCs) genetically modified to express interleukin-4 (IL-4) reduce the incidence and severity of murine collagen-induced arthritis. The present studies were performed to assess the immunoregulatory mechanisms underlying this response, by assessing the effects of IL-4 DCs on cytokine production by subsets of T helper cells. Male DBA mice ages 6-8 weeks old were immunized with type II collagen. Splenic T cells obtained during the initiation phase and the end stage of arthritis were cultured with IL-4 DCs or untransduced DCs in the presence of collagen rechallenge. Interferon-gamma (IFNgamma) and IL-17 responses were measured. Antibodies to IL-4, IL-12, and IL-23, and recombinant IL-4, IL-12, and IL-23 were used to further study the regulation of T cell cytokine production by IL-4 DCs. Splenic T cells obtained during the initiation phase of arthritis produced less IL-17 when cultured in the presence of IL-4 DCs, despite their production of increased quantities of other proinflammatory cytokines (IFNgamma and tumor necrosis factor). T cell IL-17 production after collagen rechallenge was not inhibited by a lack of IL-23, since IL-4-mediated suppression of IL-17 was not reconstituted by IL-23, an otherwise potent inducer of IL-17 production by T cells. Although IL-4 DCs can produce increased quantities of IL-12 and IFNgamma, suppression of IL-17 production by IL-4 DCs was independent of both. While IL-17 production by T cells obtained during the initiation phase of arthritis was regulated by IL-4 DCs, IL-17 production by T cells obtained during end-stage arthritis was not altered. Our data suggest that IL-4 DCs exert a therapeutic effect on collagen-induced arthritis by targeting IL-17. IL-17 suppression by IL-4 DCs is robust and is not reversed by IL-23. Timing might be important in IL-17-targeted therapy, since IL-17 production by T cells obtained during end-stage arthritis did not respond to suppression by IL-4 DCs.

Research paper thumbnail of Evidence for the expression of a second CD6 ligand by synovial fibroblasts

Arthritis & Rheumatism, 2000

Objective. CD6, a cell surface glycoprotein expressed primarily on T cells, may function as a cos... more Objective. CD6, a cell surface glycoprotein expressed primarily on T cells, may function as a costimulatory molecule and may play a role in autoreactive immune responses. Recently, a CD6 ligand termed CD166 (previously known as activated leukocyte cell adhesion molecule [ALCAM]) has been identified and shown to be expressed on activated T cells, B cells, thymic epithelium, keratinocytes, and in rheumatoid arthritis synovial tissue. However, the results of functional studies have suggested the existence of a second CD6 ligand. The present study was undertaken to seek evidence for a second CD6 ligand on cultured synovial fibroblasts.

Research paper thumbnail of Systemic Toxicity Following Administration of Sirolimus (Formerly Rapamycin) for Psoriasis

Archives of Dermatology, 1999

Background: Sirolimus (formerly rapamycin) is an im- munosuppressive agent that interferes with T... more Background: Sirolimus (formerly rapamycin) is an im- munosuppressive agent that interferes with T-cell acti- vation. After 2 individuals with psoriasis developed a cap- illary leak syndrome following treatment with oral sirolimus, lesional skin cells and activated peripheral blood cells were analyzed for induction of apoptosis. Observations: A keratome skin specimen from 1 patient with sirolimus-induced capillary leak syndrome had a

Research paper thumbnail of Molecular Interactions between T Cells and Fibroblast-Like Synoviocytes

The American Journal of Pathology, 2007

Tck also readily activated FLS to produce interleukin IL-6 and IL-8 in a cell contact-dependent m... more Tck also readily activated FLS to produce interleukin IL-6 and IL-8 in a cell contact-dependent manner that was enhanced by exogenous IL-17. Although LFA-1 and ICAM-1 co-localized at the Tck-FLS synapse, blocking the LFA-1/ICAM-1 interaction did not substantially inhibit Tck effector function. However, antibody blocking of membrane tumor necrosis factor (TNF)-␣ on the Tck surface did inhibit FLS cytokine production, thus illustrating a novel mechanism for involvement of TNF-␣ in cell-cell interactions in RA synovium and for the effectiveness of TNF-␣ blockade in the treatment of RA. (Am J

Research paper thumbnail of Activation of Synovial Fibroblasts Effector Function of Resting T Cells