A. van Houte - Academia.edu (original) (raw)

Papers by A. van Houte

Research paper thumbnail of Biocompatibility and Performance of a Modified Cellulosic and a Synthetic High Flux Dialyzer

ASAIO Journal, 1995

The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-t... more The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-triacetate (CTA), and a synthetic material: polysulphon [PS]) were assessed in 31 stable patients on hemodialysis (HD) in a randomized crossover study. Parameters evaluated included leukocytes, complement activation products C3a and C5a, cytokines, lymphocyte subpopulations, urea, creatinine, phosphate, and beta 2 microglobulin. Considering biocompatibility, the drop in the number of leukocytes was more pronounced during CTA HD compared with PS (p = 0.045), although both were low in comparison with cuprammonium dialysis in the same patients, as observed during a separate study. Both membranes induced a low and transient state of complement activation. Interleukin 1 beta and interleukin 6 could not be detected at all, whereas tumor necrosis factor alpha levels were marginally elevated before and after HD with both membranes. During the first 30 min of HD with either membrane, the numbers of CD8+ cells decreased significantly, resulting in an increase in the CD4/CD8 ratios; in addition, the number of NK cells decreased. Performance, as measured by extraction ratios for small molecular weight solutes and Kt/V urea, was significantly better during CTA dialysis (p < 0.001), but almost similar after correction for membrane surface area. On the basis of these data, it seems justified to conclude that, whereas biocompatibility of the PS dialyzer appeared slightly superior to CTA, performance of both dialyzers was comparable.

Research paper thumbnail of Preparation of a semisynthetic vaccin to Streptococcus pneumoniae type 3

Infection and Immunity, 1983

Research paper thumbnail of Killing of Escherichia coli by a granulocyte fraction occurs without recognizable ultrastructural alterations in the bacterial envelope, as studied by freeze-fracture electron microscopy

Infection and immunity, 1977

Concentrations of a highly purified rabbit polymorphonuclear leukocyte fraction that rapidly caus... more Concentrations of a highly purified rabbit polymorphonuclear leukocyte fraction that rapidly caused irreversible loss of viability of Escherichia coli (S15) but reversible envelope alterations produced no recognizable morphological changes as studied by freeze-fracture electron microscopy. These findings support previous evidence that the killing of certain gram-negative microorganisms by granulocyte fractions occurs with minimal structural or functional disorganization of cytoplasmic and outer membranes.

Research paper thumbnail of Monocyte activation in peripheral blood and dialyser eluates: phenotypic profile and cytokine release

Nephron, 2002

Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysi... more Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysis (HD)-related morbidity. The present study was designed to investigate HD-induced changes in monocytes, with respect to their phenotypic profile and cytokine release, both in peripheral blood (PB) and dialyser eluates (DE). In addition, the effect of the type of dialyser on monocyte activation was assessed. Dialyser elution was performed in 8 patients after 3 h of HD, using cuprammonium (CU) and polysulfon (PS) dialysers in a randomised cross-over design. PB samples and DE were analysed for both the expression of a variety of monocyte cell surface markers (CD62L, CD11b, CD25, HLA-DR, CD64 and CD14) by flow cytometry and IL-1beta levels. Monocytes were identified by dual labelling with antibodies against CD14. In PB, the expression of CD11b increased during HD with both devices, but was more pronounced with CU (CU versus PS: p < 0.05). CD62L decreased during HD, but only significantly...

Research paper thumbnail of Ex vivo elution of hemodialyzers. An additional criterion for the assessment of bioincompatibility

Blood purification, 1996

The analysis of hemodialysis (HD)-related bioincompatibility is focused mainly on phenomena obser... more The analysis of hemodialysis (HD)-related bioincompatibility is focused mainly on phenomena observed in peripheral blood. However, since biocompatibility originates inside the dialyzer, white blood cells (WBC) adhering to the dialyzer are probably most subject to the influence of both dialyzer membrane and dialysate. In order to collect membrane-adherent cells, a reliable and reproducible elution technique was developed. After 3 h of HD, blood was returned to the patient with 0.9% NaCl. Then, dialyzers were eluted by recirculation of phosphate-buffered saline (PBS) or PBS/3 mM EDTA for 20 min, with or without prior flushing with 200 ml PBS. Finally, remaining adherent cells were collected by an afterwash with 10% trypsin. These solutions, as well as blood samples, were analyzed for WBC count, viability and differentiation. Random eluate samples were analyzed by flow cytometry, and the influence of elution on PMN activation was tested in a separate control experiment. WBC numbers dec...

Research paper thumbnail of Granulocyte sequestration in dialysers: a comparative elution study of three different membranes

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 1995

The present study was designed to investigate the expression of activation markers on polymorphon... more The present study was designed to investigate the expression of activation markers on polymorphonuclear cells (PMN) in peripheral blood and dialyser eluates, comparing three different membranes. Eight patients were studied during HD with cellulose triacetate (CTA), cuprammonium (CU), and polysulphone (PS) dialysers in a randomized crossover design. In addition to total cell count and microscopic leukocyte differentiation, the expression of degranulation (CD63, CD66b) and adhesion (CD62L) markers on PMN was analysed in peripheral blood over time, and in dialyser eluates at the end of HD. In peripheral blood a significant drop in PMN was noted only during CU HD (P < 0.001), whereas none of the membranes induced any substantial change in the expression of the activation markers mentioned. In dialyser eluates the mean number of cells was 53 x 10(6), CTA yielding a significantly higher number as compared with CU (P = 0.05). The proportion of PMN was 81-91% (P < 0.05 versus peripher...

Research paper thumbnail of Immunogenic properties in mice of hexasaccharide from the capsular polysaccharide of Streptococcus pneumoniae type 3

Infection and immunity, 1983

Hexasaccharide (HS) containing 3 U of cellobiuronic acid was isolated from Streptococcus pneumoni... more Hexasaccharide (HS) containing 3 U of cellobiuronic acid was isolated from Streptococcus pneumoniae type 3 capsular polysaccharide S3 and coupled to bovine serum albumin (BSA), keyhole limpet hemocyanin (KLH), or tetanus toxoid (TT). The immunogenicity of these HS-protein conjugates in BALB/c mice was studied by measuring the production of circulating antibodies and the induction of protective immunity to viable S. pneumoniae type 3. Immunization of BALB/c mice with 0.5 micrograms of S3 resulted in the induction of immunoglobulin M (IgM) antibodies and complete protection against 25 U of a mean lethal dose of S. pneumoniae type 3 for 19 weeks after immunization. BALB/c mice immunized with 100 micrograms of HS9-BSA (containing 12 micrograms of HS) were also protected due to circulating IgM antibodies. Repeated injections with either 100 micrograms of HS9-BSA (three immunizations) or 100 micrograms of HS6-KLH (two immunizations) resulted in high levels of circulating IgG antibodies. T...

Research paper thumbnail of Preparation of a semisynthetic vaccine to Streptococcus pneumoniae type 3

Infection and immunity, 1983

A semisynthetic vaccine to Streptococcus pneumoniae type 3 has been developed. The hexasaccharide... more A semisynthetic vaccine to Streptococcus pneumoniae type 3 has been developed. The hexasaccharide [leads to 3)GlcpA beta(1 leads to 4)Glcp beta(1 leads to]3 was isolated from a partial acid hydrolysate of the capsular polysaccharide S3. It was coupled to stearylamine by reductamination with NaCNBH3 and then incorporated into liposomes. These haptenated liposomes were tested for immunogenicity in mice. They induced protection to a lethal dose (25 50% lethal doses) of S. pneumoniae type 3 and gave rise to immunoglobulin M antibodies. No cross-protection was observed against S. pneumoniae type 11.

Research paper thumbnail of Hapten-specific B cell blockade of the immune response to a thymus-independent-1 antigen produced by concomitant administration of a thymus-independent-2 antigen

Immunology, 1984

CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their h... more CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their hybrid male progeny. These mice mount normal responses to thymus-dependent (TD) and some thymus-independent (TI-1) antigens, while the response to TI-2 antigens is absent. Hapten-specific plaque-forming cell (PFC) responses to TD antigens can be blockaded by concomitant exposure of these mice to TI-2 antigens bearing the same hapten. This paper investigates in defective mice the blockade of their response to TNP3-LPS (trinitrophenylated lipopolysaccharide, a TI-1 antigen), imposed by DNP59-Ficoll (dinitrophenylated Ficoll, a TI-2 antigen). The effectiveness of the blocking agent, DNP59-Ficoll, differed in various inbred mouse strains: CBA/N X C3H/HeN F1 male greater than CBA/N female greater than CBA/N X C3H/HeN F1 female. The role of T cells in the observed hapten-specific blockade phenomenon was investigated using athymic CBA/N nude mice and a B cell tolerogen. Our findings indicate tha...

Research paper thumbnail of Cytokine profiles during clinical high-flux dialysis : no evidence for cytokine generation by circulating monocytes

Journal of The American Society of Nephrology, 1997

Research paper thumbnail of Hemodialysis-Induced Degranulation of Polymorphonuclear Cells: No Correlation between Membrane Markers and Degranulation Products

Nephron, 2000

Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed ... more Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed by measuring degranulation products. However, this process might also be estimated by the assessment of cell surface markers. In this study, the relationship between the expression of PMN degranulation markers (CD63 and CD66b) and the release of degranulation products [myeloperoxidase (MPO) and lactoferrin (LF)] was investigated during clinical HD in order to evaluate cell surface markers as a useful index of PMN degranulation. The expression of CD63 and CD66b on PMN and the release of MPO and LF were investigated in 10 chronic HD patients, during both heparin (HDhep) and trisodium citrate anticoagulation (HDcit), in a randomized order. Samples were drawn from both the efferent and afferent lines of the dialyzer at 0, 7.5, and 180 min. During HDhep at first passage, a major increase in MPO (from 158 +/- 32 to 448 +/- 177 microg/l, p = 0.001) and LF (from 134 +/- 52 to 260 +/- 120 microg/l, p = 0.01) was found across the dialyzer, whereas marked changes were not observed during HDcit. The expression of CD63 and CD66b increased across the dialyzer during both anticoagulation modalities, but was only significant in the case of HDhep (CD63: mean fluorescence intensity from 247 +/- 61 to 331 +/- 118, p &lt; 0.01; CD66b: mean fluorescence intensity from 340 +/- 76 to 434 +/- 103, p = 0.01). During HDhep a correlation was noted between the degranulation products and markers of both azurophilic and specific granules (MPO and CD63: r = 0.35; p &lt; 0.01; LF and CD66b: r = 0.39, p &lt; 0.01). Significant differences in the expression of CD63 and CD66b between HDhep and HDcit were not observed. When analyzing the combined data for both HDhep and HDcit, no correlation was observed between degranulation products and markers. Our data suggest that the measurements of cell surface markers may not be a reliable indicator of the degree of HD-induced PMN degranulation.

Research paper thumbnail of Effects of dialyser and dialysate on the acute phase reaction in clinical bicarbonate dialysis

Nephrology Dialysis Transplantation, 2000

In chronic haemodialysis (HD), morbidity may result from repetitive induction of the acute phase ... more In chronic haemodialysis (HD), morbidity may result from repetitive induction of the acute phase response, caused by a bioincompatible dialysis membrane and/or contaminated dialysate. In the present study, cytokine release (interleukin-6, IL-6) and subsequent production of acute phase proteins (C-reactive protein, CRP and secretory phospholipase A(2), sPLA(2)) were assessed to investigate whether the HD-induced acute phase reaction depends mainly on the type of membrane or on the sterility of the dialysate. In 11 patients, IL-6, CRP and sPLA(2) levels were assessed in blood samples drawn before (t(0)), at the end (t(180)) and 24 h after the start of HD (t(1440)). All patients were dialysed on Cuprammonium (CU) and Polysulphon (PS) dialysers and seven patients underwent an additional HD session on CU plus a dialysate filter (CUf). IL-6 levels were increased significantly at t(180) compared with t(0) (P&lt;0.02) with both CU and CUf. At t(1440), IL-6 levels had returned to baseline. In contrast, marked fluctuations did not occur during HD with PS. At t(180), IL-6 was significantly greater with CU and CUf devices, than with PS (P&lt;0.02). Following HD with CU and CUf, a significant increase in CRP was observed at t(1440), compared with postdialysis values (P&lt;/=0.05). In addition, sPLA(2) values were markedly increased at t(1440), compared with t(180), but only significant in the case of CU (P=0.01). IL-6 levels at t(180) were significantly correlated with CRP (r=0.50, P&lt;0.01) and sPLA(2) (r=0.47, P=0.01) values at t(1440). During HD with PS membranes, neither CRP nor sPLA(2) values were markedly changed. In contrast to PS, both CU and CUf resulted in elevated IL-6 plasma levels at the end of HD, compared with t(0), which correlated with increased CRP and sPLA(2) values 24 h later. Therefore, the type of membrane, rather than the bacterial quality of the dialysate, seems to be responsible for the induction of the acute phase response during clinical bicarbonate HD.

Research paper thumbnail of Low polymorphonuclear cell degranulation during citrate anticoagulation: a comparison between citrate and heparin dialysis

Nephrology Dialysis Transplantation, 1997

Key words: bio-incompatibility; citrate; heparin; PMN; degranulation; haemodialysis Introduction.... more Key words: bio-incompatibility; citrate; heparin; PMN; degranulation; haemodialysis Introduction. Haemodialysis (HD)-induced bioincompatibility includes alterations in both cellular elements and humoral factors. As far as polymorpho-Correspondence and oÂprint requests to: M. J. Nubé, Medical Center Alkmaar,

Research paper thumbnail of Lymphocyte subsets in dialyser eluates: a new parameter of bioincompatibility?

Nephrology Dialysis Transplantation, 1996

During haemodialysis (HD), several adverse reactions in peripheral blood can occur, which have be... more During haemodialysis (HD), several adverse reactions in peripheral blood can occur, which have been attributed to the bioincompatibility of the dialyser membrane. Utilizing a dialyser elution technique, we have demonstrated that polymorphonuclear cells (PMN) manifested non-membrane dependent signs of activation during HD with cellulose triacetate (CTA), cuprammonium (CU) and polysulphone (PS) membranes. In the present study, we employed this elution technique to investigate the influence of HD with these membranes on lymphocytes. Methods. Eight patients were studied during HD with CTA, CU, and PS dialysers in a randomized crossover design. Dialyser elution was performed after 3 h of HD. Besides total leukocyte count and differentiation, lymphocyte subpopulations and activation status in peripheral blood and dialyser eluates were analysed by flow cytometry. Results. Only with CU was a significant leukocyte decrease observed in peripheral blood at 30 min (P< 0.001). Neither the total number of lymphocytes nor the proportion of T(CD3+) and B(CD19+) cells had markedly changed after HD with either membrane. Meanwhile, all membranes induced a relative decline in natural killer cells -NK(CD3-/CD16+/56+)-at the end of dialysis, although this was only significant for CTA (/ ) =0.04). As for T-lymphocyte subsets, the proportion of CD4+ cells had markedly increased after three hours of HD with all three dialysers, CTA and PS being significant (P<0.05). Dialyser eluates contained 33.8-82.2 x 10 6 cells, CTA yielding the highest cell counts. The majority (81-91%) of the eluted cells consisted of PMN (dialyser eluates versus peripheral blood: P<0.05), whereas only few lymphocytes were found (4-13%, absolute 2.6 x 10 6 ). Lymphocyte subpopulations in dialyser eluates were comparable to peripheral blood at t 180 in case of CTA and CU. In contrast PS eluates contained significantly fewer T-cells Correspondence and offprint requests to: PMN in the dialyser eluates of three different membranes showed similar activation patterns in a previous study, we hypothesize that eluted lymphocytes, rather than PMN, represent a preferable parameter of bioincompatibility.

Research paper thumbnail of Clonal T- and natural killer-cell large granular lymphocyte proliferations in a single patient established by array-based comparative genomic hybridization analysis

Research paper thumbnail of Coombs-negative severe haemolytic anaemia in an immunocompetent adult following cytomegalovirus infection

European Journal of Clinical Microbiology & Infectious Diseases, 2004

Severe haemolysis is a rare, but potentially lifethreatening, complication of cytomegalovirus (CM... more Severe haemolysis is a rare, but potentially lifethreatening, complication of cytomegalovirus (CMV) infection in immunocompetent adults. Treatment with steroids or immunoglobulins, or even splenectomy, may be justified when an autoimmune mechanism can be identified as the cause of the anaemia. Described here is the case of a previously healthy patient who presented with severe haemolytic anaemia following CMV infection. The patient's haemoglobin level fell to 5.1 g/dl while extensive testing for an autoimmune mechanism remained negative. The patient made a slow but full recovery without additional medication or blood transfusions. This case demonstrates that severe haemolytic anaemia following CMV infection is possible even when presently available tests fail to show autoimmune positivity. In immunocompetent subjects a wait and see policy, with supportive care when necessary, is likely to be justified.

Research paper thumbnail of Clinical and immunological evaluation of patients with mild IgG1 deficiency

Clinical & Experimental Immunology, 1999

Serum IgG subclass concentrations were determined in patients visiting, the pulmonology out-patie... more Serum IgG subclass concentrations were determined in patients visiting, the pulmonology out-patient clinic with chronic respiratory tract problems. A total of 24 patients with a serum IgG1 concentration < 4·9 g/l (i.e. below the reference range) and normal values for IgG2, IgM and IgA were included. Patients with a selective IgG1 deficiency were vaccinated with a 23-valent pneumococcal polysaccharide vaccine. There were nine patients with a poor antibody response to pneumococcal capsular polysaccharide antigens. Responsiveness to protein antigens was intact in all patients. Patients with pneumonia showed a significantly lower anti-polysaccharide response in the IgG2 subclass than patients without pneumonia. Patients with recurrent sinusitis showed a significantly lower response in the IgA isotype after vaccination with pneumococcal polysaccharide vaccine compared with non-sinusitis patients. It can be concluded that patients with recurrent sinopulmonary infections and a mild IgG1 subclass deficiency have an impaired IgG1 anti-polysaccharide response, which can extend to decreased IgG2 and IgA anti-polysaccharide responses.

Research paper thumbnail of Characterization of immunogenic properties of polyclonal T cell vaccine intended for the treatment of rheumatoid arthritis

Bulletin of Experimental Biology and Medicine, 2007

CBA/N mice have an X-linked B-cell defect which prevents them from responding to nonmitogenic thy... more CBA/N mice have an X-linked B-cell defect which prevents them from responding to nonmitogenic thymus-independent (TI-2) antigens such as haptenated Ficoll. The CBA/N mice do, however, respond to another group of thymus-independent (TI-i) antigens among which are haptenated liposomes. The F1 male progeny of CBA/N female mice express the same characteristics. Hapten-specific plaque-forming cell (PFC) responses to haptenated proteins (thymus-dependent, TD, antigens) by CBA/N mice and CBA/N x C3H/HeN F1 male mice can be blocked by concomitant exposure to TI-2 antigens bearing the same hapten. Simultaneous exposure to haptenated liposomes (TI-I antigen) and TD antigens, however, results in a synergistic response to the hapten if the antigens share common epitopes. The tripeptide-enlarged hapten dinitrophenyl-f-alanylglycylglycine (J), conjugated to phosphatidyl-ethanolamine (PE) and incorporated into liposomal model membranes, was used throughout the experiments. In F1 male mice the moderate responses to TD antigens could be restored to values equivalent to those seen in F1 female mice. This adjuvant effect of haptenated liposomes is hapten-specific, time-dependent, and restricted to certain structural forms of the liposomes.

Research paper thumbnail of Biocompatibility and Performance of a Modified Cellulosic and a Synthetic High Flux Dialyzer

ASAIO Journal, 1995

The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-t... more The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-triacetate (CTA), and a synthetic material: polysulphon [PS]) were assessed in 31 stable patients on hemodialysis (HD) in a randomized crossover study. Parameters evaluated included leukocytes, complement activation products C3a and C5a, cytokines, lymphocyte subpopulations, urea, creatinine, phosphate, and beta 2 microglobulin. Considering biocompatibility, the drop in the number of leukocytes was more pronounced during CTA HD compared with PS (p = 0.045), although both were low in comparison with cuprammonium dialysis in the same patients, as observed during a separate study. Both membranes induced a low and transient state of complement activation. Interleukin 1 beta and interleukin 6 could not be detected at all, whereas tumor necrosis factor alpha levels were marginally elevated before and after HD with both membranes. During the first 30 min of HD with either membrane, the numbers of CD8+ cells decreased significantly, resulting in an increase in the CD4/CD8 ratios; in addition, the number of NK cells decreased. Performance, as measured by extraction ratios for small molecular weight solutes and Kt/V urea, was significantly better during CTA dialysis (p &amp;amp;lt; 0.001), but almost similar after correction for membrane surface area. On the basis of these data, it seems justified to conclude that, whereas biocompatibility of the PS dialyzer appeared slightly superior to CTA, performance of both dialyzers was comparable.

Research paper thumbnail of Empyema in a patient treated with infliximab: it is not what it seems

Annals of the Rheumatic Diseases, 2005

Research paper thumbnail of Biocompatibility and Performance of a Modified Cellulosic and a Synthetic High Flux Dialyzer

ASAIO Journal, 1995

The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-t... more The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-triacetate (CTA), and a synthetic material: polysulphon [PS]) were assessed in 31 stable patients on hemodialysis (HD) in a randomized crossover study. Parameters evaluated included leukocytes, complement activation products C3a and C5a, cytokines, lymphocyte subpopulations, urea, creatinine, phosphate, and beta 2 microglobulin. Considering biocompatibility, the drop in the number of leukocytes was more pronounced during CTA HD compared with PS (p = 0.045), although both were low in comparison with cuprammonium dialysis in the same patients, as observed during a separate study. Both membranes induced a low and transient state of complement activation. Interleukin 1 beta and interleukin 6 could not be detected at all, whereas tumor necrosis factor alpha levels were marginally elevated before and after HD with both membranes. During the first 30 min of HD with either membrane, the numbers of CD8+ cells decreased significantly, resulting in an increase in the CD4/CD8 ratios; in addition, the number of NK cells decreased. Performance, as measured by extraction ratios for small molecular weight solutes and Kt/V urea, was significantly better during CTA dialysis (p &amp;amp;lt; 0.001), but almost similar after correction for membrane surface area. On the basis of these data, it seems justified to conclude that, whereas biocompatibility of the PS dialyzer appeared slightly superior to CTA, performance of both dialyzers was comparable.

Research paper thumbnail of Preparation of a semisynthetic vaccin to Streptococcus pneumoniae type 3

Infection and Immunity, 1983

Research paper thumbnail of Killing of Escherichia coli by a granulocyte fraction occurs without recognizable ultrastructural alterations in the bacterial envelope, as studied by freeze-fracture electron microscopy

Infection and immunity, 1977

Concentrations of a highly purified rabbit polymorphonuclear leukocyte fraction that rapidly caus... more Concentrations of a highly purified rabbit polymorphonuclear leukocyte fraction that rapidly caused irreversible loss of viability of Escherichia coli (S15) but reversible envelope alterations produced no recognizable morphological changes as studied by freeze-fracture electron microscopy. These findings support previous evidence that the killing of certain gram-negative microorganisms by granulocyte fractions occurs with minimal structural or functional disorganization of cytoplasmic and outer membranes.

Research paper thumbnail of Monocyte activation in peripheral blood and dialyser eluates: phenotypic profile and cytokine release

Nephron, 2002

Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysi... more Monocyte activation and subsequent cytokine generation is presumed to be involved in haemodialysis (HD)-related morbidity. The present study was designed to investigate HD-induced changes in monocytes, with respect to their phenotypic profile and cytokine release, both in peripheral blood (PB) and dialyser eluates (DE). In addition, the effect of the type of dialyser on monocyte activation was assessed. Dialyser elution was performed in 8 patients after 3 h of HD, using cuprammonium (CU) and polysulfon (PS) dialysers in a randomised cross-over design. PB samples and DE were analysed for both the expression of a variety of monocyte cell surface markers (CD62L, CD11b, CD25, HLA-DR, CD64 and CD14) by flow cytometry and IL-1beta levels. Monocytes were identified by dual labelling with antibodies against CD14. In PB, the expression of CD11b increased during HD with both devices, but was more pronounced with CU (CU versus PS: p < 0.05). CD62L decreased during HD, but only significantly...

Research paper thumbnail of Ex vivo elution of hemodialyzers. An additional criterion for the assessment of bioincompatibility

Blood purification, 1996

The analysis of hemodialysis (HD)-related bioincompatibility is focused mainly on phenomena obser... more The analysis of hemodialysis (HD)-related bioincompatibility is focused mainly on phenomena observed in peripheral blood. However, since biocompatibility originates inside the dialyzer, white blood cells (WBC) adhering to the dialyzer are probably most subject to the influence of both dialyzer membrane and dialysate. In order to collect membrane-adherent cells, a reliable and reproducible elution technique was developed. After 3 h of HD, blood was returned to the patient with 0.9% NaCl. Then, dialyzers were eluted by recirculation of phosphate-buffered saline (PBS) or PBS/3 mM EDTA for 20 min, with or without prior flushing with 200 ml PBS. Finally, remaining adherent cells were collected by an afterwash with 10% trypsin. These solutions, as well as blood samples, were analyzed for WBC count, viability and differentiation. Random eluate samples were analyzed by flow cytometry, and the influence of elution on PMN activation was tested in a separate control experiment. WBC numbers dec...

Research paper thumbnail of Granulocyte sequestration in dialysers: a comparative elution study of three different membranes

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, 1995

The present study was designed to investigate the expression of activation markers on polymorphon... more The present study was designed to investigate the expression of activation markers on polymorphonuclear cells (PMN) in peripheral blood and dialyser eluates, comparing three different membranes. Eight patients were studied during HD with cellulose triacetate (CTA), cuprammonium (CU), and polysulphone (PS) dialysers in a randomized crossover design. In addition to total cell count and microscopic leukocyte differentiation, the expression of degranulation (CD63, CD66b) and adhesion (CD62L) markers on PMN was analysed in peripheral blood over time, and in dialyser eluates at the end of HD. In peripheral blood a significant drop in PMN was noted only during CU HD (P < 0.001), whereas none of the membranes induced any substantial change in the expression of the activation markers mentioned. In dialyser eluates the mean number of cells was 53 x 10(6), CTA yielding a significantly higher number as compared with CU (P = 0.05). The proportion of PMN was 81-91% (P < 0.05 versus peripher...

Research paper thumbnail of Immunogenic properties in mice of hexasaccharide from the capsular polysaccharide of Streptococcus pneumoniae type 3

Infection and immunity, 1983

Hexasaccharide (HS) containing 3 U of cellobiuronic acid was isolated from Streptococcus pneumoni... more Hexasaccharide (HS) containing 3 U of cellobiuronic acid was isolated from Streptococcus pneumoniae type 3 capsular polysaccharide S3 and coupled to bovine serum albumin (BSA), keyhole limpet hemocyanin (KLH), or tetanus toxoid (TT). The immunogenicity of these HS-protein conjugates in BALB/c mice was studied by measuring the production of circulating antibodies and the induction of protective immunity to viable S. pneumoniae type 3. Immunization of BALB/c mice with 0.5 micrograms of S3 resulted in the induction of immunoglobulin M (IgM) antibodies and complete protection against 25 U of a mean lethal dose of S. pneumoniae type 3 for 19 weeks after immunization. BALB/c mice immunized with 100 micrograms of HS9-BSA (containing 12 micrograms of HS) were also protected due to circulating IgM antibodies. Repeated injections with either 100 micrograms of HS9-BSA (three immunizations) or 100 micrograms of HS6-KLH (two immunizations) resulted in high levels of circulating IgG antibodies. T...

Research paper thumbnail of Preparation of a semisynthetic vaccine to Streptococcus pneumoniae type 3

Infection and immunity, 1983

A semisynthetic vaccine to Streptococcus pneumoniae type 3 has been developed. The hexasaccharide... more A semisynthetic vaccine to Streptococcus pneumoniae type 3 has been developed. The hexasaccharide [leads to 3)GlcpA beta(1 leads to 4)Glcp beta(1 leads to]3 was isolated from a partial acid hydrolysate of the capsular polysaccharide S3. It was coupled to stearylamine by reductamination with NaCNBH3 and then incorporated into liposomes. These haptenated liposomes were tested for immunogenicity in mice. They induced protection to a lethal dose (25 50% lethal doses) of S. pneumoniae type 3 and gave rise to immunoglobulin M antibodies. No cross-protection was observed against S. pneumoniae type 11.

Research paper thumbnail of Hapten-specific B cell blockade of the immune response to a thymus-independent-1 antigen produced by concomitant administration of a thymus-independent-2 antigen

Immunology, 1984

CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their h... more CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their hybrid male progeny. These mice mount normal responses to thymus-dependent (TD) and some thymus-independent (TI-1) antigens, while the response to TI-2 antigens is absent. Hapten-specific plaque-forming cell (PFC) responses to TD antigens can be blockaded by concomitant exposure of these mice to TI-2 antigens bearing the same hapten. This paper investigates in defective mice the blockade of their response to TNP3-LPS (trinitrophenylated lipopolysaccharide, a TI-1 antigen), imposed by DNP59-Ficoll (dinitrophenylated Ficoll, a TI-2 antigen). The effectiveness of the blocking agent, DNP59-Ficoll, differed in various inbred mouse strains: CBA/N X C3H/HeN F1 male greater than CBA/N female greater than CBA/N X C3H/HeN F1 female. The role of T cells in the observed hapten-specific blockade phenomenon was investigated using athymic CBA/N nude mice and a B cell tolerogen. Our findings indicate tha...

Research paper thumbnail of Cytokine profiles during clinical high-flux dialysis : no evidence for cytokine generation by circulating monocytes

Journal of The American Society of Nephrology, 1997

Research paper thumbnail of Hemodialysis-Induced Degranulation of Polymorphonuclear Cells: No Correlation between Membrane Markers and Degranulation Products

Nephron, 2000

Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed ... more Degranulation of polymorphonuclear leukocytes (PMN) during hemodialysis (HD) is usually assessed by measuring degranulation products. However, this process might also be estimated by the assessment of cell surface markers. In this study, the relationship between the expression of PMN degranulation markers (CD63 and CD66b) and the release of degranulation products [myeloperoxidase (MPO) and lactoferrin (LF)] was investigated during clinical HD in order to evaluate cell surface markers as a useful index of PMN degranulation. The expression of CD63 and CD66b on PMN and the release of MPO and LF were investigated in 10 chronic HD patients, during both heparin (HDhep) and trisodium citrate anticoagulation (HDcit), in a randomized order. Samples were drawn from both the efferent and afferent lines of the dialyzer at 0, 7.5, and 180 min. During HDhep at first passage, a major increase in MPO (from 158 +/- 32 to 448 +/- 177 microg/l, p = 0.001) and LF (from 134 +/- 52 to 260 +/- 120 microg/l, p = 0.01) was found across the dialyzer, whereas marked changes were not observed during HDcit. The expression of CD63 and CD66b increased across the dialyzer during both anticoagulation modalities, but was only significant in the case of HDhep (CD63: mean fluorescence intensity from 247 +/- 61 to 331 +/- 118, p &lt; 0.01; CD66b: mean fluorescence intensity from 340 +/- 76 to 434 +/- 103, p = 0.01). During HDhep a correlation was noted between the degranulation products and markers of both azurophilic and specific granules (MPO and CD63: r = 0.35; p &lt; 0.01; LF and CD66b: r = 0.39, p &lt; 0.01). Significant differences in the expression of CD63 and CD66b between HDhep and HDcit were not observed. When analyzing the combined data for both HDhep and HDcit, no correlation was observed between degranulation products and markers. Our data suggest that the measurements of cell surface markers may not be a reliable indicator of the degree of HD-induced PMN degranulation.

Research paper thumbnail of Effects of dialyser and dialysate on the acute phase reaction in clinical bicarbonate dialysis

Nephrology Dialysis Transplantation, 2000

In chronic haemodialysis (HD), morbidity may result from repetitive induction of the acute phase ... more In chronic haemodialysis (HD), morbidity may result from repetitive induction of the acute phase response, caused by a bioincompatible dialysis membrane and/or contaminated dialysate. In the present study, cytokine release (interleukin-6, IL-6) and subsequent production of acute phase proteins (C-reactive protein, CRP and secretory phospholipase A(2), sPLA(2)) were assessed to investigate whether the HD-induced acute phase reaction depends mainly on the type of membrane or on the sterility of the dialysate. In 11 patients, IL-6, CRP and sPLA(2) levels were assessed in blood samples drawn before (t(0)), at the end (t(180)) and 24 h after the start of HD (t(1440)). All patients were dialysed on Cuprammonium (CU) and Polysulphon (PS) dialysers and seven patients underwent an additional HD session on CU plus a dialysate filter (CUf). IL-6 levels were increased significantly at t(180) compared with t(0) (P&lt;0.02) with both CU and CUf. At t(1440), IL-6 levels had returned to baseline. In contrast, marked fluctuations did not occur during HD with PS. At t(180), IL-6 was significantly greater with CU and CUf devices, than with PS (P&lt;0.02). Following HD with CU and CUf, a significant increase in CRP was observed at t(1440), compared with postdialysis values (P&lt;/=0.05). In addition, sPLA(2) values were markedly increased at t(1440), compared with t(180), but only significant in the case of CU (P=0.01). IL-6 levels at t(180) were significantly correlated with CRP (r=0.50, P&lt;0.01) and sPLA(2) (r=0.47, P=0.01) values at t(1440). During HD with PS membranes, neither CRP nor sPLA(2) values were markedly changed. In contrast to PS, both CU and CUf resulted in elevated IL-6 plasma levels at the end of HD, compared with t(0), which correlated with increased CRP and sPLA(2) values 24 h later. Therefore, the type of membrane, rather than the bacterial quality of the dialysate, seems to be responsible for the induction of the acute phase response during clinical bicarbonate HD.

Research paper thumbnail of Low polymorphonuclear cell degranulation during citrate anticoagulation: a comparison between citrate and heparin dialysis

Nephrology Dialysis Transplantation, 1997

Key words: bio-incompatibility; citrate; heparin; PMN; degranulation; haemodialysis Introduction.... more Key words: bio-incompatibility; citrate; heparin; PMN; degranulation; haemodialysis Introduction. Haemodialysis (HD)-induced bioincompatibility includes alterations in both cellular elements and humoral factors. As far as polymorpho-Correspondence and oÂprint requests to: M. J. Nubé, Medical Center Alkmaar,

Research paper thumbnail of Lymphocyte subsets in dialyser eluates: a new parameter of bioincompatibility?

Nephrology Dialysis Transplantation, 1996

During haemodialysis (HD), several adverse reactions in peripheral blood can occur, which have be... more During haemodialysis (HD), several adverse reactions in peripheral blood can occur, which have been attributed to the bioincompatibility of the dialyser membrane. Utilizing a dialyser elution technique, we have demonstrated that polymorphonuclear cells (PMN) manifested non-membrane dependent signs of activation during HD with cellulose triacetate (CTA), cuprammonium (CU) and polysulphone (PS) membranes. In the present study, we employed this elution technique to investigate the influence of HD with these membranes on lymphocytes. Methods. Eight patients were studied during HD with CTA, CU, and PS dialysers in a randomized crossover design. Dialyser elution was performed after 3 h of HD. Besides total leukocyte count and differentiation, lymphocyte subpopulations and activation status in peripheral blood and dialyser eluates were analysed by flow cytometry. Results. Only with CU was a significant leukocyte decrease observed in peripheral blood at 30 min (P< 0.001). Neither the total number of lymphocytes nor the proportion of T(CD3+) and B(CD19+) cells had markedly changed after HD with either membrane. Meanwhile, all membranes induced a relative decline in natural killer cells -NK(CD3-/CD16+/56+)-at the end of dialysis, although this was only significant for CTA (/ ) =0.04). As for T-lymphocyte subsets, the proportion of CD4+ cells had markedly increased after three hours of HD with all three dialysers, CTA and PS being significant (P<0.05). Dialyser eluates contained 33.8-82.2 x 10 6 cells, CTA yielding the highest cell counts. The majority (81-91%) of the eluted cells consisted of PMN (dialyser eluates versus peripheral blood: P<0.05), whereas only few lymphocytes were found (4-13%, absolute 2.6 x 10 6 ). Lymphocyte subpopulations in dialyser eluates were comparable to peripheral blood at t 180 in case of CTA and CU. In contrast PS eluates contained significantly fewer T-cells Correspondence and offprint requests to: PMN in the dialyser eluates of three different membranes showed similar activation patterns in a previous study, we hypothesize that eluted lymphocytes, rather than PMN, represent a preferable parameter of bioincompatibility.

Research paper thumbnail of Clonal T- and natural killer-cell large granular lymphocyte proliferations in a single patient established by array-based comparative genomic hybridization analysis

Research paper thumbnail of Coombs-negative severe haemolytic anaemia in an immunocompetent adult following cytomegalovirus infection

European Journal of Clinical Microbiology & Infectious Diseases, 2004

Severe haemolysis is a rare, but potentially lifethreatening, complication of cytomegalovirus (CM... more Severe haemolysis is a rare, but potentially lifethreatening, complication of cytomegalovirus (CMV) infection in immunocompetent adults. Treatment with steroids or immunoglobulins, or even splenectomy, may be justified when an autoimmune mechanism can be identified as the cause of the anaemia. Described here is the case of a previously healthy patient who presented with severe haemolytic anaemia following CMV infection. The patient's haemoglobin level fell to 5.1 g/dl while extensive testing for an autoimmune mechanism remained negative. The patient made a slow but full recovery without additional medication or blood transfusions. This case demonstrates that severe haemolytic anaemia following CMV infection is possible even when presently available tests fail to show autoimmune positivity. In immunocompetent subjects a wait and see policy, with supportive care when necessary, is likely to be justified.

Research paper thumbnail of Clinical and immunological evaluation of patients with mild IgG1 deficiency

Clinical & Experimental Immunology, 1999

Serum IgG subclass concentrations were determined in patients visiting, the pulmonology out-patie... more Serum IgG subclass concentrations were determined in patients visiting, the pulmonology out-patient clinic with chronic respiratory tract problems. A total of 24 patients with a serum IgG1 concentration < 4·9 g/l (i.e. below the reference range) and normal values for IgG2, IgM and IgA were included. Patients with a selective IgG1 deficiency were vaccinated with a 23-valent pneumococcal polysaccharide vaccine. There were nine patients with a poor antibody response to pneumococcal capsular polysaccharide antigens. Responsiveness to protein antigens was intact in all patients. Patients with pneumonia showed a significantly lower anti-polysaccharide response in the IgG2 subclass than patients without pneumonia. Patients with recurrent sinusitis showed a significantly lower response in the IgA isotype after vaccination with pneumococcal polysaccharide vaccine compared with non-sinusitis patients. It can be concluded that patients with recurrent sinopulmonary infections and a mild IgG1 subclass deficiency have an impaired IgG1 anti-polysaccharide response, which can extend to decreased IgG2 and IgA anti-polysaccharide responses.

Research paper thumbnail of Characterization of immunogenic properties of polyclonal T cell vaccine intended for the treatment of rheumatoid arthritis

Bulletin of Experimental Biology and Medicine, 2007

CBA/N mice have an X-linked B-cell defect which prevents them from responding to nonmitogenic thy... more CBA/N mice have an X-linked B-cell defect which prevents them from responding to nonmitogenic thymus-independent (TI-2) antigens such as haptenated Ficoll. The CBA/N mice do, however, respond to another group of thymus-independent (TI-i) antigens among which are haptenated liposomes. The F1 male progeny of CBA/N female mice express the same characteristics. Hapten-specific plaque-forming cell (PFC) responses to haptenated proteins (thymus-dependent, TD, antigens) by CBA/N mice and CBA/N x C3H/HeN F1 male mice can be blocked by concomitant exposure to TI-2 antigens bearing the same hapten. Simultaneous exposure to haptenated liposomes (TI-I antigen) and TD antigens, however, results in a synergistic response to the hapten if the antigens share common epitopes. The tripeptide-enlarged hapten dinitrophenyl-f-alanylglycylglycine (J), conjugated to phosphatidyl-ethanolamine (PE) and incorporated into liposomal model membranes, was used throughout the experiments. In F1 male mice the moderate responses to TD antigens could be restored to values equivalent to those seen in F1 female mice. This adjuvant effect of haptenated liposomes is hapten-specific, time-dependent, and restricted to certain structural forms of the liposomes.

Research paper thumbnail of Biocompatibility and Performance of a Modified Cellulosic and a Synthetic High Flux Dialyzer

ASAIO Journal, 1995

The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-t... more The biocompatibility and performance of two high flux membranes (modified cellulosic: cellulose-triacetate (CTA), and a synthetic material: polysulphon [PS]) were assessed in 31 stable patients on hemodialysis (HD) in a randomized crossover study. Parameters evaluated included leukocytes, complement activation products C3a and C5a, cytokines, lymphocyte subpopulations, urea, creatinine, phosphate, and beta 2 microglobulin. Considering biocompatibility, the drop in the number of leukocytes was more pronounced during CTA HD compared with PS (p = 0.045), although both were low in comparison with cuprammonium dialysis in the same patients, as observed during a separate study. Both membranes induced a low and transient state of complement activation. Interleukin 1 beta and interleukin 6 could not be detected at all, whereas tumor necrosis factor alpha levels were marginally elevated before and after HD with both membranes. During the first 30 min of HD with either membrane, the numbers of CD8+ cells decreased significantly, resulting in an increase in the CD4/CD8 ratios; in addition, the number of NK cells decreased. Performance, as measured by extraction ratios for small molecular weight solutes and Kt/V urea, was significantly better during CTA dialysis (p &amp;amp;lt; 0.001), but almost similar after correction for membrane surface area. On the basis of these data, it seems justified to conclude that, whereas biocompatibility of the PS dialyzer appeared slightly superior to CTA, performance of both dialyzers was comparable.

Research paper thumbnail of Empyema in a patient treated with infliximab: it is not what it seems

Annals of the Rheumatic Diseases, 2005