Telomerase activity in B and T lymphocytes of patients with systemic lupus erythematosus

OBJECTIVE: To evaluate telomerase activity as a marker of lymphocyte proliferation in systemic lupus erythematosus (SLE). METHODS: CD19+, CD4+, and CD8+ lymphocytes were isolated from the peripheral blood of nine patients with SLE and nine healthy controls by means of magnetic bead-coupled antibodies and tested for telomerase activity with the TRAP assay. RESULTS: Telomerase activity was significantly increased in CD19+ B cells from patients with SLE. CD4+ and CD8+ T cells from lupus patients displayed increased mean telomerase activity, although the difference from normal controls did not reach statistical significance. CONCLUSIONS: Increased telomerase activity in the B and the T cell lineage might indicate activation and proliferation of these lymphocytes.     

Increased Fas and Bcl-2 expression on peripheral mononuclear cells from patients with active juvenile-onset systemic lupus erythematosus

OBJECTIVE: To determine expressions of Fas and Bcl-2 on peripheral blood T and B lymphocytes from patients with juvenile-onset systemic lupus erythematosus (JSLE). METHODS: Thirty-eight patients with JSLE and 21 healthy controls were studied. Eleven JSLE patients with SLEDAI score >or= 8 were categorized as active. Freshly isolated peripheral blood mononuclear cells were stained for lymphocyte markers CD3, CD4, CD8, and CD19 and for Fas and Bcl-2 molecules. Cell protein expression was measured by 3-color flow cytometry. RESULTS: Percentages of lymphocytes positively stained for Fas antigen and cytoplasmic expression of Bcl-2 measured by mean fluorescence intensity from patients were significantly increased compared to controls on CD3+, CD4+, and CD8+ T cells. Patients with active disease had higher percentages of CD19+ B cells positive for Fas antigen compared to patients with inactive lupus. A direct statistical correlation was observed between Fas and Bcl-2 expression on CD19+ B cells and SLE Disease Activity Index score. CONCLUSION: Patients with juvenile-onset SLE show upregulation of apoptosis-related proteins. Patients with active and inactive disease have a different profile of Fas and Bcl-2 expression.     

Small-bowel involvement in systemic lupus erythematosus: a morphometric and immunohistochemical study.

BACKGROUND: We have investigated the intestinal mononuclear cell subpopulations in patients with systemic lupus erythematosus (SLE) and correlated these with the disease activity. METHODS: Eighteen female outpatients were studied; in 10 of them lupus activity was measured with the Lupus Activity Criteria Count and the SLE Disease Activity Index. Eight patients were in lupus remission. The control group consisted of 10 healthy volunteers. Peroral jejunal biopsy was performed in all individuals, at the angle of Treitz, using a Watson capsule, under X-ray control. Histologic studies analysed the villous to crypt ratio, lamina propria cells, and intraepithelial lymphocyte count. Immunohistochemical evaluation was carried out with the indirect immunoperoxidase technique, using monoclonal antibodies against CD3, CD4, CD8, D1, D7, D9, and M1. RESULTS: Lamina propria CD3+, CD8+, D7+, and M1+ cells from patients with SLE did not differ significantly from those of controls. CD4+ cells were decreased in all patients with SLE, especially in the clinically inactive patients. D1+ and D9+ cells were also decreased in all patients. CONCLUSION: The finding of quantitative abnormalities in the cell-mediated immunity of the intestinal mucosa may reflect systemic defects of the immune system in SLE.     

CD8+ lymphocytes from patients with systemic lupus erythematosus sustain, rather than suppress, spontaneous polyclonal IgG production and synergize with CD4+ cells to support autoantibody synthesis

The cellular requirements for B cell hyperactivity in systemic lupus erythematosus (SLE) were studied. Removal of either CD8+ or CD4+ lymphocyte markedly decreased the spontaneous in vitro production of polyclonal IgG and of antigen-specific (anti-double-stranded DNA and antinucleoprotein) antibodies by SLE peripheral blood mononuclear cells (PBMC). The CD8+ lymphocytes that sustained IgG production were CD3+, HLA-DR+, and their activity was abrogated by preincubation with anti-HLA-DR monoclonal antibody. When both CD4+ and CD8+ cells were removed, the readdition of either subset partially restored polyclonal IgG production, but both cell subsets were required to reconstitute autoantibody production. Purified SLE B cell cultures, which generated only 15% of the IgG produced by unseparated PBMC, were fully reconstituted only by mixtures of CD4+ with CD8+ cells, and with CD8-, CD4-, CD16+ cells. At least part of the support for spontaneous IgG production can be attributed to endogenous interleukin-2 and interleukin-6.     

Small-Bowel Involvement in Systemic Lupus Erythematosus: A Morphometric and Immunohistochemical Study

Background: We have investigated the intestinal mononuclear cell subpopulations in patients with systemic lupus erythematosus (SLE) and correlated these with the disease activity. Methods: Eighteen female outpatients were studied; in 10 of them lupus activity was measured with the Lupus Activity Criteria Count and the SLE Disease Activity Index. Eight patients were in lupus remission. The control group consisted of 10 healthy volunteers. Peroral jejunal biopsy was performed in all individuals, at the angle of Treitz, using a Watson capsule, under X-ray control. Histologic studies analysed the villous to crypt ratio, lamina propria cells, and intraepithelial lymphocyte count. Immunohistochemical evaluation was carried out with the indirect immunoperoxidase technique, using monoclonal antibodies against CD3, CD4, CD8, D1, D7, D9, and M1. Results: Lamina propria CD3+, CD8+, D7+, and M1+ cells from patients with SLE did not differ significantly from those of controls. CD4+ cells were decreased in all patients with SLE, especially in the clinically inactive patients. D1+ and D9+ cells were also decreased in all patients. Conclusion: The finding of quantitative abnormalities in the cell-mediated immunity of the intestinal mucosa may reflect systemic defects of the immune system in SLE.     

Predominance of CD8+ T lymphocytes among periglomerular infiltrating cells and link to the prognosis of class III and class IV lupus nephritis

OBJECTIVE: Recent studies have revealed a potential implication of CD8+ T lymphocytes in the pathogenesis of systemic lupus erythematosus (SLE) through their ability to induce tissue damage. The aim of the present study was to analyze the localization of CD8+ cells in the kidneys of patients with class III and class IV lupus nephritis and to establish correlations with histologic, biologic, and clinical features of SLE. METHODS: Twenty-five consecutive SLE patients with class III or class IV lupus nephritis were enrolled. Phenotype analyses of blood lymphocytes and renal immunohistochemistry studies were performed. RESULTS: CD8+ T cells were the predominant kidney-infiltrating subset of cells. The mean +/- SD numbers of CD8+ T cells and CD4+ T cells were 66.2 +/- 65.2/mm(2) and 19.3 +/- 29.4/mm(2), respectively. There was a significant correlation between the percentage of blood CD3+,CD8+,DR+ cells and the total number of renal CD8+ T cells (r = 0.42, P = 0.039). Renal CD8+ T cell infiltration correlated well with the renal activity index (r = 0.63, P = 0.0007) and with high serum creatinine levels (r = 0.75, P = 0.0001). This CD8+ T cell infiltrate, which was predominantly in the periglomerular area, was correlated with cellular crescents and Bowman's capsule rupture and was associated with a poor response after conventional induction therapy. CONCLUSION: CD8+ T lymphocytes infiltrate the periglomerular area in patients with severe (class III and class IV) lupus nephritis and are linked to a poor outcome after induction therapy. These results reveal a new potential effector pathway operant in lupus nephritis.     

Selective accumulation of CCR4+ T lymphocytes into renal tissue of patients with lupus nephritis

OBJECTIVE: Some chemokine receptors, such as CCR5 and CCR4, are differentially expressed on Th1 and Th2 cells. To determine whether differential expression of the chemokine receptors occurs in patients with lupus nephritis, we examined the expression of CCR4 and CCR5 on peripheral blood lymphocytes and mononuclear cells infiltrated into the renal tissue of patients with lupus nephritis. METHODS: The expression of CCR4 and CCR5 on CD4+,CD45RO+ cells was analyzed by flow cytometry and compared between patients with systemic lupus erythematosus (SLE) and healthy controls. Correlation between the absolute number of CCR4+ or CCR5+ cells and clinical parameters was also analyzed. Mononuclear infiltrates in the renal tissue of SLE patients were analyzed for the expression of CCR4, CCR5, and CD4 by immunohistochemical staining. RESULTS: The absolute number of CCR4+, but not CCR5+, T lymphocytes in the peripheral blood was significantly decreased in the patients with SLE compared with that in the healthy controls, and this positively correlated with the serum levels of C3 and CH50. Most of the CD4+ T lymphocytes that infiltrated into the renal tissue of the patients with lupus nephritis expressed CCR4, but not CCR5. CONCLUSION: These results suggest that CCR4+ T lymphocytes in peripheral blood, which represent Th2 cells, preferentially migrate into the renal tissue of patients with lupus nephritis. The maldistribution of CCR4+ T lymphocytes might be involved in the pathogenesis of lupus nephritis.     

系统性红斑狼疮初发患者外周血T细胞免疫球蛋白及黏蛋白域蛋白-3及其配体半乳糖凝集素-9表达水平和意义

目的 通过检测T细胞免疫球蛋白及黏蛋白域蛋白(TIM)-3及其配体半乳糖凝集素-9在系统性红斑狼疮(SLE)初发患者外周血的表达水平,探讨其在SLE发病中的可能作用.方法 选取SLE初发患者33例,健康对照组26名,采用流式细胞术检测2组CD4+TIM-3+、CD8+TIM-3+细胞表达水平;实时荧光定量聚合酶链反应(PCR)技术比较2组外周血单个核细胞(PBMCs)半乳糖凝集素-9 mRNA表达水平;同时记录SLE组SLE疾病活动指数(SLEDAI)、补体C3水平和外周血淋巴细胞计数.两独立样本比较采用Mann-Whitney U检验;相关关系采用Spearman等级相关分析.结果 SLE组CD4+TIM-3+、CD8+TIM-3+细胞比率显著高于对照组(P＜0.01);其中CD4+TIM-3+、CD8+TIM-3+细胞数目与SLEDAI呈正相关(r=0.517,P＜0.01;=400,P＜0.05);与补体C3水平呈负相关(r=-0.487,P＜0.05;r=-0.395,P＜0.05).SLE组PBMCs半乳糖凝集素-9 mRNA表达较对照组显著上调(P＜0.05).结论 TIM-3-半乳糖凝集素-9通路可能参与了SLET细胞免疫调节,并与疾病活动性相关.

Abstract：

Objective To investigate the expression of T cell immunoglobulin domain and mucin domain (TIM)-3 and its ligand Galectin-9 in the peripheral blood of initial systemic lupus erythematosus (SLE)patients,and explore their effects on SLE.Methods The percentages of CD4+TIM-3+,CD8+TIM-3+cells from 33 SLE patients and 26 normal controls were detected by flow cytometry,and the Galectin-9 gene expression of PBMCs was determined by real-time PCR The SLE Disease Activity Index(SLEDAI),C3 level and lymphocyte count were evaluated.Mann-Whitney U test was used for independent samples analysis and Spearmen's test was used for correlation analysis.Results The percentages of CD4+TIM-3+ and CD8+TIM-3+ cells were markedly increased in SLE group than those of the control group(P<0.01).In particular,the CD4+TIM-3+,CD8+TIM-3+ level Was positively correlated with SLEDAI (r=0.517,P＜0.01;r=0.400,P＜0.05);but negatively correlated with C3(r=0.487,P＜0.05;r=0.395,P＜0.05).The Galectin-9 mRNA in SLE PBMCs was higher than that of the controls(P<0.05).Conclusion TIM-3-Galectin-9 pathway may be involved in T cell immune regulation of SLE,and is related to disease activity.     

Decreased number of peripheral blood CD4 + CD29+ lymphocytes and increased in vitro spontaneous production of anti-DNA antibodies in patients with active systemic lupus erythematosus.

Flow cytometric 2-color analysis of peripheral blood lymphocytes from patients with systemic lupus erythematosus (SLE) showed a reduction of relative and absolute number of CD4+ CD29+ cells compared to matched healthy individuals. This abnormality was more marked in patients with active/very active disease. Absolute number of CD4+ CD29+ cells was negatively correlated with spontaneous anti-DNA Ig production that we demonstrated to be a laboratory index strongly correlated with a clinical disease activity score. A decrease of the percentage of CD8+ CD29+ lymphocytes in patients with active disease was also observed.     

Peripheral blood T,B, and NK cells in relation to histological hepatitis activity and fibrosis stage in chronic hepatitis C

BACKGROUND/AIMS: Many data on the pathogenesis of chronic hepatitis C have pointed to host's immune system disorders and a high variety of virus. However, there are no known criteria that could prognose the course of chronic hepatitis C infection. The analysis of T and B lymphocyte subpopulations in the peripheral blood was undertaken in patients with chronic hepatitis C of more than 6 months of duration. METHODOLOGY: Fluorescein isothiocyanate or phycoerythryne conjugated monoclonal antibodies for CD3+, CD4+, CD8+, CD19+, CD3++ HLA DR+, CD16++ CD56+ were used. The correlation between histological hepatitis activity and fibrosis (according Scheuer's scale) and the distribution of lymphocytes in the peripheral blood was sought. RESULTS: All patients with chronic hepatitis showed statistically significant increase in active lymphocytes CD3++ HLA DR+ and CD16++ CD56+ NK cells in peripheral blood. We observed the correlation between these cells and histological hepatitis activity and fibrosis. There was no correlation between the value of CD3+ and CD8+ cells and the stage of liver failure. In the early stage of chronic hepatitis C we noted decrease CD4+ cells with increase B cells CD19+. CD4+/CD8+ ratio was maintained as slightly decreased in chronic hepatitis C in favor of lymphocytes CD8+. CONCLUSIONS: The results show the correlation between peripheral blood value of activated T cell (HLA DR+) and NK cells with histological activity and fibrosis in chronic hepatitis C. Lymphocyte T (CD4+, CD8+) and B (CD19+) did not correlate with grade and stage of hepatitis C.     

Relationship between CD4+/CD8+ T cell ratio and T cell activation in systemic lupus erythematosus.

We investigated the relationship between the ratio of CD4+ to CD8+ T cells (CD4/CD8 ratio) and T cell activation, indicated by human leukocyte antigen (HLA)-DR expression, in patients with systemic lupus erythematosus (SLE). We found that the ratio was decreased in SLE patients and that this was significantly related to expression of HLA-DR by CD8+ (but not CD4+) T cells. These findings may assist in understanding the pathogenesis of SLE. In some SLE patients, the CD4/CD8 ratio and HLA-DR expression may be good indicators of therapeutic efficacy.     

Phenotypic characteristics of B cells in Behçet's disease: increased activity in B cell subsets

OBJECTIVE: Increased numbers of spontaneous Ig secreting B cells and elevated immunoglobulin levels have been described in Beh?et's disease (BD), in addition to changes in numbers and activities of T cells, natural killer cells, and monocyte-macrophages. We investigated other characteristics of B cells in BD. METHODS: B lymphocyte subsets (CD19+CD5+, CD19+CD13+, CD19+CD28+, CD19+CD33+, CD19+CD80+, CD5+CD19+CD45RA+, CD5+CD19+CD45RO+) were phenotypically evaluated in 50 patients with BD, 80 healthy subjects, and 20 other patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and sepsis. RESULTS: Although the B cell number (CD19+) was normal, CD13 and CD33 positive B cells were more numerous in BD and sepsis compared to healthy controls and patients with RA and SLE. The percentage of CD45RO positive B cells was higher in both BD and sepsis, while the percentage of CD80 positive B cells was high only in BD. There was no increase in the CD5+CD19+ B cell subset, previously shown to be increased in several autoimmune diseases. Naive (CD45RA) and memory (CD45RO) status of CD5+CD19+ and CD5-CD19+ B cells showed that CD45RA expression was higher in CD5+CD19+ B cells, whereas expression of both CD45RA and CD45RO was higher in the CD5-CD19+ B cell group compared with healthy controls. CONCLUSION: Although the total B cell number was normal, increased levels of activated and memory B cell subsets suggest a modified B cell function in BD, which may be related to a weak stimulus by an unknown external antigen.     

Telomere length analysis in monocytes and lymphocytes from patients with systemic lupus erythematosus using multi-color flow-FISH

In order to analyse telomere length in subsets of human peripheral blood lymphocytes and monocytes, we modified a recently developed multicolor flow- fluorescent in situ hybridization (FISH) methodology that combines flow-FISH and antibody staining for cell surface antigens. We analysed telomere length of peripheral blood mononuclear cells in a group of 22 patients with systemic lupus erythematosus (SLE) and 20 age-matched healthy donors. We found that neither CD4+, CD8+, CD19+ cells nor CD14+ monocytes have significantly shorter telomeres compared with their healthy counterparts. On the basis of these findings, we then used monocyte telomere length as internal reference in order to control for intra-individual variability in telomere length. By using this approach, we could demonstrate significant telomere shortening in all three lymphocyte subsets (in all cases P < 0.05) compared with monocytes. However, these differences did not vary significantly between SLE patients and controls. In summary, telomere lengths in subpopulations of hematopoietic cells can be monitored in patients with SLE using multicolor flow-FISH. While confirming data by other groups on telomere length in lymphocyte subpopulations, our data argue against an increased proliferation rate of peripheral blood monocytes reflected by accelerated telomere shortening in patients with SLE.     

CD7– T cells in rheumatoid arthritis

Objective. Rheumatoid arthritis (RA) is characterized by decreased expression of CD7 in the peripheral blood and in the synovium. The present study was designed to identify the basis for and functional consequences of this decreased expression. Methods. Peripheral blood lymphocytes from normal controls and from patients with RA or systemic lupus erythematosus (SLE), and T cell lines derived from rheumatoid synovium, were evaluated using 3-color fluorescence-activated cell sorter analysis. Results. Normal subjects and most SLE patients expressed homogeneous, bright CD7 on CD4+, CD45RA+ cells, whereas RA patients demonstrated a significantly increased proportion of CD7– cells. T cell lines derived from rheumatoid synovium demonstrated a striking deficiency of CD7 on CD4+, CD45RA– cells. CD4+, CD45RA+ cells from RA patients changed phenotype after in vitro activation to CD45RA negativity, with up-regulation of CD7. CD7–, CD4+, CD45RA– cells were assessed for their ability to induce pokeweed mitogen-driven IgM and IgM-rheumatoid factor synthesis, and they were found to be potent helper/inducer cells. An increased population of CD7-, CD4+ cells in peripheral blood was found to predict a low response to recall antigens. Conclusion. The low expression of CD7 in RA may explain some of the immune abnormalities which may contribute to the pathogenesis of this disease.     

Roles of CCR2 and CXCR3 in the T cell-mediated response occurring during lupus flares

OBJECTIVE: Infiltrating lymphocytes have been demonstrated to play an important role in the tissue injury that occurs in systemic lupus erythematosus (SLE). Inflammatory chemokines control lymphocyte traffic through their interaction with T cell chemokine receptors. In this study we assessed the expression of chemokine receptors on T cell subsets of patients with active or inactive SLE. METHODS: Forty-four SLE patients (40 women and 4 men) were included in the study. The patients were divided according to their SLE Disease Activity Index (SLEDAI), which resulted in a group of patients with inactive SLE (n = 27) and a group with active SLE (n = 17). The control group was composed of 22 healthy blood donors. A disease control group consisted of 18 patients infected with human immunodeficiency virus. Expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3, CXCR4, and CX3CR1 was assessed on whole blood samples by immunofluorescence analysis. RESULTS: On T lymphocytes, significant differences between the SLE patients and controls were observed only in the expression of CCR2 and CXCR3. On monocytes, no significant differences in CCR2 expression were observed between the healthy controls and the SLE patients. The proportion of CD8+,CCR2+ T cells was significantly lower in the SLE patients compared with the controls (mean +/- SD 2.3 +/- 1.3% and 3.5 +/- 3.2% in the active and inactive SLE groups, respectively, versus 21 +/- 24% in controls; P < 0.0001 for both). The CD4+,CCR2+ subset was represented similarly among the controls and patients with inactive SLE (16.7 +/- 5.8% and 12.8 +/- 8.1%, respectively) but was depleted in patients with active SLE (7.1 +/- 4.4%; P < 0.0001 versus controls). The active SLE group expressed significantly lower circulating levels of CD4+,CCR2+ T cells than did the inactive disease group (P = 0.007). A negative correlation was found between the proportion of CD4+,CCR2+ T cells and the SLEDAI (r = -0.43, P = 0.005, by Spearman's correlation). Proportions of CD8+,CXCR3+ T cells were similar between the SLE groups and the control group (58 +/- 22.6% in active SLE, 47.1 +/- 20% in inactive SLE, and 59.4 +/- 17.3% in controls). The proportion of CXCR3-expressing CD4+ T cells was decreased in the active disease group (23.5 +/- 3.2% versus 39.9 +/- 12.5% in controls; P = 0.008) but not in the inactive disease group (34.8 +/- 9.5%). A trend toward a significant negative correlation was observed between the decreased proportion of CD4+,CXCR3+ T cells and the SLEDAI (P = 0.08). Following in vitro activation of purified CD4 T cells, only CCR2 was internalized, whereas expression of CXCR3 was retained in activated CD4 cells. CONCLUSION: The numbers of circulating CD4+,CXCR3+ and CD4+,CCR2+ T cells are selectively decreased during SLE flares. A decrease in the number of circulating CD4+ T cells expressing CCR2 and/or CXCR3 could serve as a biomarker of the SLE flare.     

CD7- T cells in rheumatoid arthritis.

OBJECTIVE. Rheumatoid arthritis (RA) is characterized by decreased expression of CD7 in the peripheral blood and in the synovium. The present study was designed to identify the basis for and functional consequences of this decreased expression. METHODS. Peripheral blood lymphocytes from normal controls and from patients with RA or systemic lupus erythematosus (SLE), and T cell lines derived from rheumatoid synovium, were evaluated using 3-color fluorescence-activated cell sorter analysis. RESULTS. Normal subjects and most SLE patients expressed homogeneous, bright CD7 on CD4+, CD45RA+ cells, whereas RA patients demonstrated a significantly increased proportion of CD7- cells. T cell lines derived from rheumatoid synovium demonstrated a striking deficiency of CD7 on CD4+, CD45RA- cells. CD4+, CD45RA+ cells from RA patients changed phenotype after in vitro activation to CD45RA negativity, with up-regulation of CD7. CD7-, CD4+, CD45RA- cells were assessed for their ability to induce pokeweed mitogen-driven IgM and IgM-rheumatoid factor synthesis, and they were found to be potent helper/inducer cells. An increased population of CD7-, CD4+ cells in peripheral blood was found to predict a low response to recall antigens. CONCLUSION. The low expression of CD7 in RA may explain some of the immune abnormalities which may contribute to the pathogenesis of this disease.     

Immune recovery after autologous PBSC transplantation without in vitro graft manipulation for refractory systemic lupus erythematosus

Autologous hematopoietic SCT (ASCT) has been investigated as salvage therapy for refractory systemic lupus erythematosus (SLE). Although immune recovery after ASCT with in vitro purging of lymphocytes has been extensively studied, little information is available about immune recovery after ASCT without in vitro purging. Therefore, we analyzed the immune recovery of a patient who successfully underwent ASCT without in vitro purging for refractory SLE. In addition to the numbers of PBL subsets, T-cell receptor rearrangement excision circles (TRECs) and the T-cell receptor repertoire diversity of both CD4+ and CD8+ T cells were sequentially analyzed. All SLE-related symptoms disappeared within 3 months after ASCT and the serum anti-dsDNA Ab became undetectable. The number of CD4+CD45RO+ memory T cells remained lower than that in healthy adult controls, but the number of CD4+CD45RA+ na?ve T cells showed a rapid increase after ASCT. TRECs of both CD4+ and CD8+ T cells were strongly suppressed before ASCT, but consistently increased after ASCT. The T-cell receptor repertoire of CD8+ T cells was skewed before ASCT, but the diversity recovered after ASCT. ASCT with the reinfusion of a large number of autologous T cells did not impair the recovery of naive T cells or resetting of the immune system.     

Studies on the T4+2H4+ cell of peripheral blood lymphocyte in systemic lupus erythematosus]

The cell surface phenotype of peripheral blood lymphocytes in patients with systemic lupus erythematosus (SLE) was studied with the anti-T4+, T8+ and T4+2H4+ monoclonal antibodies by flow cytometry. 13 patients with active SLE had a markedly low percentage of T4+2H4+ cells but had normal percentage of T8+ cells. Our results reveal that the influence of T cell to B cell is not only because of the quantity of T cells, also because of the function of T cells. The abnormality of T4+2H4+ cells may be important in the pathogenesis of SLE.     

Roles of CCR2 and CXCR3 in the T cell–mediated response occurring during lupus flares

Objective

Infiltrating lymphocytes have been demonstrated to play an important role in the tissue injury that occurs in systemic lupus erythematosus (SLE). Inflammatory chemokines control lymphocyte traffic through their interaction with T cell chemokine receptors. In this study we assessed the expression of chemokine receptors on T cell subsets of patients with active or inactive SLE.

Methods

Forty‐four SLE patients (40 women and 4 men) were included in the study. The patients were divided according to their SLE Disease Activity Index (SLEDAI), which resulted in a group of patients with inactive SLE (n = 27) and a group with active SLE (n = 17). The control group was composed of 22 healthy blood donors. A disease control group consisted of 18 patients infected with human immunodeficiency virus. Expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3, CXCR4, and CX3CR1 was assessed on whole blood samples by immunofluorescence analysis.

Results

On T lymphocytes, significant differences between the SLE patients and controls were observed only in the expression of CCR2 and CXCR3. On monocytes, no significant differences in CCR2 expression were observed between the healthy controls and the SLE patients. The proportion of CD8+,CCR2+ T cells was significantly lower in the SLE patients compared with the controls (mean ± SD 2.3 ± 1.3% and 3.5 ± 3.2% in the active and inactive SLE groups, respectively, versus 21 ± 24% in controls; P < 0.0001 for both). The CD4+,CCR2+ subset was represented similarly among the controls and patients with inactive SLE (16.7 ± 5.8% and 12.8 ± 8.1%, respectively) but was depleted in patients with active SLE (7.1 ± 4.4%; P < 0.0001 versus controls). The active SLE group expressed significantly lower circulating levels of CD4+,CCR2+ T cells than did the inactive disease group (P = 0.007). A negative correlation was found between the proportion of CD4+,CCR2+ T cells and the SLEDAI (r = −0.43, P = 0.005, by Spearman's correlation). Proportions of CD8+,CXCR3+ T cells were similar between the SLE groups and the control group (58 ± 22.6% in active SLE, 47.1 ± 20% in inactive SLE, and 59.4 ± 17.3% in controls). The proportion of CXCR3‐expressing CD4+ T cells was decreased in the active disease group (23.5 ± 3.2% versus 39.9 ± 12.5% in controls; P = 0.008) but not in the inactive disease group (34.8 ± 9.5%). A trend toward a significant negative correlation was observed between the decreased proportion of CD4+,CXCR3+ T cells and the SLEDAI (P = 0.08). Following in vitro activation of purified CD4 T cells, only CCR2 was internalized, whereas expression of CXCR3 was retained in activated CD4 cells.

Conclusion

The numbers of circulating CD4+,CXCR3+ and CD4+,CCR2+ T cells are selectively decreased during SLE flares. A decrease in the number of circulating CD4+ T cells expressing CCR2 and/or CXCR3 could serve as a biomarker of the SLE flare.

     

Analysis of bone marrow and peripheral blood immunoregulatory lymphocytes in patients with myelodysplastic syndrome

The cell surface phenotype of immunoregulatory lymphocytes in bone marrow (BM) and peripheral blood (PB) in myelodysplastic syndrome (MDS), a stem cell disorder, was analyzed. Mononuclear cells from 25 patients with refractory anemia (RA) and nine with RA with an excess of blasts (RAEB) were characterized by two-color flow cytometry using various monoclonal antibodies. No significant change of CD3+, CD4+, and CD8+ cells in PB, but a decrease of the percent of positive cells for CD8+ among the total lymphocyte (%CD8+ +) was noticed in RA patients. On the other hand, in BM of RA patients, a decrease in the number of CD4+cells, but not CD8+ +cells, was noted. In RAEB patients, the absolute numbers of CD3+, CD4+, CD8+, and CD8+ +cells in BM were decreased; however, the ratio of these lymphocytes was not changed. No change was observed among the CD4 + subsets in PB of RA or RAEB patients. In BM, a decrease in percentage of CD4+ CD45RA+ (% CD4+ CD45RA+; naive cell) and increases in CD4+ CD45RO+ (% CD4+ CD45RO+; memory cell) and CD4+ CD29+ (%CD4+ CD29+; helper/inducer) among CD4+ cells were found in both RA and RAEB patients. Analysis of the CD8+ + subset showed an increased number of CD8+ + CD11a+ cells (activated CTL) in both BM and PB of RA patients, but not of RAEB patients. Furthermore, increments in CD56+ and CD16+ cells among CD3- cells (natural killer; NK cells) were seen in RA patients but not in RAEB patients. It remains unclear whether lymphocytes in MDS patients were involved in the abnormal (MDS) clones, but our results regarding the increments of CD8+ + CD11a+ and NK cells in RA patients suggest that the mechanism of immune surveillance against the abnormal MDS clones was activated in these RA patients, but not in RAEB patients. Further investigation is required to clarify the functions of these immunoregulatory lymphocytes in MDS patients.