T Cell Responses and Regulation and the Impact of In Vitro IL‐10 and TGF‐β Modulation During Treatment of Active Tuberculosis

Mycobacterium tuberculosis (Mtb) is particularly challenging for the immune system being an intracellular pathogen, and a variety of T cell subpopulations are activated by the host defence mechanism. In this study, we investigated T cell responses and regulation in active TB patients with drug‐sensitive Mtb (N = 18) during 24 weeks of efficient anti‐TB therapy. T cell activation, differentiation, regulatory T cell (Treg) subsets, Mtb‐induced T cell proliferation and in vitro IL‐10 and TGF‐β modulation were analysed by flow cytometry at baseline and after 8 and 24 weeks of therapy, while soluble cytokines in culture supernatants were analysed by a 9‐plex Luminex assay. Successful treatment resulted in significantly reduced co‐expression of HLA‐DR/CD38 and PD‐1/CD38 on both CD4⁺ and CD8⁺ T cells, while the fraction of CD4⁺CD25^highCD127^low Tregs (P = 0.017) and CD4⁺CD25^highCD127^low CD147⁺ Tregs (P = 0.029) showed significant transient increase at week 8. In vitro blockade of IL‐10/TGF‐β upon Mtb antigen stimulation significantly lowered the fraction of ESAT‐6‐specific CD4⁺CD25^highCD127^low Tregs at baseline (P = 0.047), while T cell proliferation and cytokine production were unaffected. Phenotypical and Mtb‐specific T cell signatures may serve as markers of effective therapy, while the IL‐10/TGF‐β pathway could be a target for early inhibition to facilitate Mtb clearance. However, larger clinical studies are needed for verification before concluding.     

Interleukin‐10‐secreting type 1 regulatory T cells in rodents and humans

Summary: Interleukin‐10 (IL‐10)‐secreting T regulatory type 1 (Tr1) cells are defined by their specific cytokine production profile, which includes the secretion of high levels of IL‐10 and transforming growth factor‐β(TGF‐β), and by their ability to suppress antigen‐specific effector T‐cell responses via a cytokine‐dependent mechanism. In contrast to the naturally occurring CD4⁺CD25⁺ T regulatory cells (Tregs) that emerge directly from the thymus, Tr1 cells are induced by antigen stimulation via an IL‐10‐dependent process in vitro and in vivo. Specialized IL‐10‐producing dendritic cells, such as those in an immature state or those modulated by tolerogenic stimuli, play a key role in this process. We propose to use the term Tr1 cells for all IL‐10‐producing T‐cell populations that are induced by IL‐10 and have regulatory activity. The full biological characterization of Tr1 cells has been hampered by the difficulty in generating these cells in vitro and by the lack of specific marker molecules. However, it is clear that Tr1 cells play a key role in regulating adaptive immune responses both in mice and in humans. Further work to delineate the specific molecular signature of Tr1 cells, to determine their relationship with CD4⁺CD25⁺ Tregs, and to elucidate their respective role in maintaining peripheral tolerance is crucial to advance our knowledge on this Treg subset. Furthermore, results from clinical protocols using Tr1 cells to modulate immune responses in vivo in autoimmunity, transplantation, and chronic inflammatory diseases will undoubtedly prove the biological relevance of these cells in immunotolerance.     

Reduced maternal regulatory T cell numbers and increased T helper type 2 cytokine production are associated with elevated levels of immunoglobulin E in cord blood

Background There is evidence that the basis of an atopic‐skewed immune response is acquired early in life, perhaps at the fetal stage. Thus, we hypothesized that the development of the fetal immune system might be influenced by maternal regulatory T cells (Treg) and maternal T cell cytokine production during pregnancy. The aim of the present study was to assess the influence of maternal Treg and cytokine production during pregnancy on Treg and atopy at birth. Methods Within the mother–child study LINA (Lifestyle and Environmental factors and their Influence on Newborns Allergy risk), we determined the frequency and function of Treg and the total IgE concentration in pregnant women in the 34th week of gestation and in corresponding cord bloods at birth (n=24). Furthermore, we assessed how maternal mitogen‐induced T‐helper type 1/T‐helper type 2 and inflammatory cytokines influence the level of cord blood Treg and IgE. Results Frequencies of CD4⁺CD25^high T cells were higher (P=0.001), whereas percentages of FOXP3⁺ T cells were lower (P<0.001) in cord blood cells compared with maternal blood. Reduced maternal CD4⁺CD25^high Treg frequencies correlated with increased total IgE concentrations at the 34th week of gestation (r=?0.32, P=0.028) and with increased IgE concentrations in cord blood (r=?0.50, P<0.001). Elevated maternal mitogen‐induced Th2 cytokine production was related to increased total IgE levels in the serum of corresponding cord bloods (IL‐4, r=0.53; IL‐5, r=0.43; IL‐13, r=0.52). Conclusions Because cord blood IgE has been shown to be predictive for allergic diseases in early childhood, our results indicate that reduced maternal Treg numbers and increased Th2 cytokine production during pregnancy might influence the allergy risk of the child. Cite this as: D. Hinz, J. C. Simon, C. Maier‐Simon, L. Milkova, S. Röder, U. Sack, M. Borte, I. Lehmann and G. Herberth, Clinical & Experimental Allergy, 2010 (40) 419–426.     

Immunomodulatory vitamin D effects on regulatory T-cells and cytokines in an in vitro study on patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease affecting various organs. Decreased numbers of regulatory T-cells (Treg cells; CD4⁺CD25^highFoxp3⁺) are associated with the pathogenesis of SLE. A vitamin D deficiency was observed in many lupus patients. In the present study, peripheral blood mononuclear cells were isolated and cultured in the presence or absence of vitamin D, and total Tregs percentage was analyzed by flow cytometry. In addition, the level of expressions of Foxp3, TGFβ, and IL6 genes were analyzed by real-time-PCR. The results indicated that vitamin D treatment increased the percentage of Treg cells, and the expression of Foxp3 and TGFβ, and decreased the expression of IL6 in SLE patients.     

Interleukin‐17 Facilitates the Immune Suppressor Capacity of High‐Grade Glioma‐Derived CD4 (+) CD25 (+) Foxp3 (+) T Cells Via Releasing Transforming Growth Factor Beta

High‐grade glioma is a malignant tumour; the pathogenesis is to be further investigated. Interleukin (IL)‐17 is an inflammatory cytokine. Chronic inflammation is a pathological feature of cancer. This study aimed to characterize the glioma‐derived IL‐17⁺ regulatory T cells (Treg). In this study, single cells were isolated from surgically removed high‐grade glioma tissue and examined by flow cytometry. The immune suppressor effect of IL‐17⁺ Tregs on CD8⁺ T cells was assessed in vitro. The results showed that abundant IL‐17⁺ Tregs were found in high‐grade glioma tissue. The immune suppressor molecule, transforming growth factor (TGF)‐beta, was detected in the IL‐17⁺ Tregs. The proliferation of CD8⁺ T cells was suppressed by culturing with the IL‐17⁺ Tregs, which was partially abrogated by neutralizing antibodies of either TGF‐beta or IL‐17 and completely abrogated by neutralizing antibodies against both TGF‐beta and IL‐17. In conclusion, IL‐17⁺ Tregs exist in the high‐grade glioma tissue; this subset of T cells can suppress CD8⁺ T cell activities via releasing TGF‐beta and IL‐17.     

Interleukin 10 and dendritic cells are the main suppression mediators of regulatory T cells in human neurocysticercosis

Neurocysticercosis is caused by the establishment of Taenia solium cysticerci in the central nervous system. It is considered that, during co‐evolution, the parasite developed strategies to modulate the host's immune response. The action mechanisms of regulatory T cells in controlling the immune response in neurocysticercosis are studied in this work. Higher blood levels of regulatory T cells with CD4⁺CD45RO⁺forkhead box protein 3 (FoxP3)^high and CD4⁺CD25^highFoxP3⁺CD95^high phenotype and of non‐regulatory CD4⁺CD45RO⁺FoxP3^med T cells were found in neurocysticercosis patients with respect to controls. Interestingly, regulatory T cells express higher levels of cytotoxic T lymphocyte antigen 4 (CTLA‐4), lymphocyte‐activation gene 3 (LAG‐3), programmed death 1 (PD‐1) and glucocorticoid‐induced tumour necrosis factor receptor (GITR), suggesting a cell‐to‐cell contact mechanism with dendritic cells. Furthermore, higher IL‐10 and regulatory T cell type 1 (Tr1) levels were found in neurocysticercosis patients’ peripheral blood, suggesting that the action mechanism of regulatory T cells involves the release of immunomodulatory cytokines. No evidence was found of the regulatory T cell role in inhibiting the proliferative response. Suppressive regulatory T cells from neurocysticercosis patients correlated negatively with late activated lymphocytes (CD4⁺CD38⁺). Our results suggest that, during neurocysticercosis, regulatory T cells could control the immune response, probably by a cell‐to‐cell contact with dendritic cells and interleukin (IL)‐10 release by Tr1, to create an immunomodulatory environment that may favour the development of T. solium cysticerci and their permanence in the central nervous system.     

Loss of regulatory characteristics in CD4+CD25+/hi T cells induced by impaired transforming growth factor beta secretion in pneumoconiosis

Pneumoconiosis is caused by the accumulation of airborne dust in the lung, which stimulates a progressive inflammatory response that ultimately results in lung fibrosis and respiratory failure. It is possible that regulatory cells in the immune system could function to suppress inflammation and possibly slow or reverse disease progression. However, results in this study suggest that in pneumoconiosis patients, the regulatory T cells (Tregs) and B cells are functionally impaired. First, we found that pneumoconiosis patients presented an upregulation of CD4⁺CD25⁺ T cells compared to controls, whereas the CD4⁺CD25⁺ and CD4⁺CD25^hi T cells were enriched with Th1‐ and Th17‐like cells but not Foxp3‐expressing Treg cells and evidenced by significantly higher T‐bet, interferon (IFN)‐γ, and interleukin (IL)‐17 expression but lower Foxp3 and transforming growth factor (TGF)‐β expression. Regarding the CD4⁺CD25^hi T‐cell subset, the frequency of this cell type in pneumoconiosis patients was significantly reduced compared to controls, together with a reduction in Foxp3 and TGF‐β and an enrichment in T‐bet, RORγt, IFN‐γ, and IL‐17. This skewing toward Th1 and Th17 types of inflammation could be driven by monocytes and B cells, since after depleting CD14⁺ monocytes and CD19⁺ B cells, the levels of IFN‐γ and IL‐17 were significantly decreased. Whole peripheral blood mononuclear cells and isolated monocytes and B cells in pneumoconiosis patients also presented reduced capacity of TGF‐β secretion. Furthermore, monocytes and B cells from pneumoconiosis patients presented reduced capacity in inducing Foxp3 upregulation, a function that could be rescued by exogenous TGF‐β. Together, these data indicated a potential pathway for the progression of pneumoconiosis through a loss of Foxp3⁺ Treg cells associated with impaired TGF‐β secretion.     

Peripherally Circulating CD4(+) FOXP3(+) CXCR3(+) T Regulatory Cells Correlate with Renal Allograft Function

Peripheral immunoregulation depends on T regulatory cell trafficking into the allograft to modulate the local alloresponse. Little is known about the relevance of trafficking receptors for Tregs after solid organ transplantation in humans. In this study, expression of the peripheral chemokine receptors CXCR3 and CCR5 on CD4⁺ FOXP3⁺ Treg cells was analysed and correlated with allograft function in renal transplant recipients. Flow cytometry analysis of peripheral blood mononuclear cells of 54 renal transplant recipients receiving a calcineurin inhibitor‐based immunosuppression was performed for CD4, CD25, FOXP3, CXCR3 and CCR5 within the first 18 months post‐transplantation. Correlation analysis of chemokine receptor expression and glomerular filtration rate as calculated by MDRD (eGFR) was performed. Expression of the peripheral homing receptors CXCR3 (r = 0.44, P < 0.05) and CCR5 (r = 0.45, P < 0.05) on FOXP3⁺ Tregs correlated with renal allograft function (eGFR) in patients receiving tacrolimus (n = 28), but not cyclosporine A (CsA) (n = 26). CsA but not tacrolimus reduced surface expression of CXCR3 on FOXP3⁺ Tregs in renal transplant recipients as correlated to trough levels (r = ?0.42, P < 0.05). In contrast to CD4⁺ CXCR3⁺ CD25^lo T cells, flow‐sorted CD4⁺ CXCR3⁺ CD25^hi Tregs isolated from healthy individuals did not produce IFNγ or IL‐17 ex vivo and expressed high levels of GARP mRNA both at baseline as well as after TCR activation indicating functional regulatory activity. Expression of the peripheral trafficking receptors CXCR3 and CCR5 on FOXP3⁺ Tregs is associated with renal allograft function. These results suggest that Treg trafficking may also depend on the interaction of CXCR3 or CCR5 and their respective ligands.     

Regulatory T cells in the periphery

Summary: Recognition of a systemic antigen by CD4⁺ T cells in a lymphopenic host leads to the sequential generation of pathogenic effector cells and protective CD25⁺ forkhead box protein (Foxp3⁺) regulatory T cells (Tregs) in the periphery. Such an experimental model is potentially valuable for defining the stimuli that determine the balance of effector and regulatory T cells. Our studies have shown that interleukin‐2 (IL‐2) enhances the development of effector cells and is essential for the peripheral generation of regulatory cells. Other models of peripheral Treg generation suggest that the concentration of antigen, the nature of the antigen‐presenting cells, and cytokines such as transforming growth factor‐β and IL‐10 may all influence the peripheral generation of Tregs.     

Serotonin decreases the production of Th1/Th17 cytokines and elevates the frequency of regulatory CD4+ T‐cell subsets in multiple sclerosis patients

Excessive levels of proinflammatory cytokines in the CNS are associated with reduced serotonin (5‐HT) synthesis, a neurotransmitter with diverse immune effects. In this study, we evaluated the ability of exogenous 5‐HT to modulate the T‐cell behavior of patients with MS, a demyelinating autoimmune disease mediated by Th1 and Th17 cytokines. Here, 5‐HT attenuated, in vitro, T‐cell proliferation and Th1 and Th17 cytokines production in cell cultures from MS patients. Additionally, 5‐HT reduced IFN‐γ and IL‐17 release by CD8⁺ T cells. By contrast, 5‐HT increased IL‐10 production by CD4⁺ T cells from MS patients. A more accurate analysis of these IL‐10‐secreting CD4⁺ T cells revealed that 5‐HT favors the expansion of FoxP3⁺CD39⁺ regulatory T cells (Tregs) and type 1 regulatory T cells. Notably, this neurotransmitter also elevated the frequency of Treg17 cells, a novel regulatory T‐cell subset. The effect of 5‐HT in upregulating CD39⁺ Treg and Treg17 cells was inversely correlated with the number of active brain lesions. Finally, in addition to directly reducing cytokine production by purified Th1 and Th17 cells, 5‐HT enhanced in vitro Treg function. In summary, our data suggest that serotonin may play a protective role in the pathogenesis of MS.     

Targeting cytokines secreted by CD4+CD25highCD127low regulatory T cells inhibits ovarian cancer progression

Epithelial ovarian cancer (EOC) is one of the major malignant cancers with high rates of early metastasis in which regulatory T cells (Tregs) play an important role. Tregs suppress immune responses and promote the development of tumours in patients with EOC. However, the underlying mechanisms remain unclear. In this study, we found higher levels of CD4⁺CD25^highCD127^low Tregs in patients with EOC than in patients with benign ovarian tumours and healthy donors. The immune inhibitory effect of Tregs functions by maintaining high levels of immunosuppressive cytokines in EOC. The high levels of Tregs and related cytokines (TGF‐β1 or IL‐10) were associated with lymphatic metastasis and FIGO stages of patients with EOC. Expression of matrix metalloproteinase (MMP)‐2 and tissue inhibitors of metalloproteinase (TIMP)‐2 in EOC cell lines were significantly regulated in the coculture experiment with CD4⁺CD25^highCD127^low Tregs sorted from EOC patients. Levels of MMP‐2 and TIMP‐2 conversely changed after blocking IL‐10R and TGF‐β1R in EOC cells. The invasion ability of EOC cells was also significantly downregulated in this process. The metastasis of EOC cells was correlated with the levels of TGF‐β1 or IL‐10. These findings suggested that immunosuppressive cytokines secreted by CD4⁺ Tregs could be a novel target for inhibiting EOC progression.     

The Ex Vivo Induction of Human CD103+ CD25hi Foxp3+ CD4+ and CD8+ Tregs is IL‐2 and TGF‐β1 Dependent

The expression of the integrin αE (CD103), may enhance the retention of regulatory T cells to peripheral inflammatory sites and possibly contribute to their suppressive potential. The aim of this study was to define the regulatory role of IL‐2 and TGF‐β1 on the CD103 expression and the optimal in vitro conditions for the induction/expansion of human CD4⁺ and CD8⁺ Tregs. Cord blood mononuclear cells (CBMC) were stimulated under various culture conditions, including anti‐CD3, anti‐CD28, IL‐2 and TGF‐β1. TGF‐β1 and IL‐2 were both required for optimal expression of CD103. In addition, TGF‐β1 and IL‐2 synergistically induced CD103 expression on CD8⁺ T cells, whereas, only additive induced expression was noted on CD4⁺ T cells. Surprisingly, CD103 expression was not dependent upon CD28 costimulation. IL‐2 also played a central role in CD103 expression by CD25^hi Foxp3+ Tregs. IL‐2, TGF‐β1 and anti‐CD3 defined the optimal stimulatory conditions favouring the induction/expansion of both CD4⁺ and CD8⁺ human Tregs from naive CBMC. Thus, this study provides new insights into the regulatory role of IL‐2 upon CD103 expression by human cord blood CD4⁺ and CD8⁺ T cells. Furthermore, it identifies the in vitro culture conditions driving the differentiation of the novel phenotype CD4⁺ and CD8⁺ CD103⁺ CD25^hi Foxp3+ Tregs from human CBMC.     

The associations of circulating CD4+CD25high regulatory T cells and TGF-β with disease activity and clinical course in patients with adult-onset Still's disease

Objective. To determine circulating levels of CD4⁺CD25^high regulatory T (Treg) cells and transforming growth factor-β (TGF-β) in patients with adult-onset Still's disease (AOSD) and to examine the associations with disease activity and clinical course of this disease. Methods. The frequencies of circulating CD4⁺CD25^high Treg cells in 52 active AOSD patients, 42 active systemic lupus erythematosus (SLE) patients, and 22 healthy controls (HCs) were determined using flow cytometry analysis. Levels of serum TGF-β and soluble interleukin-2 receptor (sIL-2R) were measured by enzyme-linked immunosorbent assay. Results. Significantly lower levels of circulating CD4⁺CD25^high Treg cells and serum TGF-β were found in AOSD patients and SLE patients than those found in HCs. Levels of circulating CD4⁺CD25^high Treg cells and TGF-β were inversely correlated with disease activity scores for AOSD patients and SLE patients. Circulating CD4⁺CD25^high Treg cell frequencies were positively correlated with serum TGF-β levels for patients with both diseases. Levels of circulating CD4⁺CD25^high Treg cells and TGF-β significantly increased, paralleling clinical remission and the decrease in levels of C-reactive protein and soluble interleukin-2 receptor after effective therapy in AOSD patients. AOSD patients with monocyclic course had significantly higher levels of circulating CD4⁺CD25^high Treg cells and TGF-β compared to those with polycyclic and chronic articular course. Conclusion. Diminished levels of circulating CD4⁺CD25^high Treg cells and TGF-β, and inverse correlation with disease activity in patients with AOSD and SLE might be involved in the pathogenesis of both diseases. Increased levels of circulating CD4⁺CD25^high Treg cells or TGF-β might be associated with a favorable clinical course in AOSD patients.     

Low circulating CD4(+) CD25(+) Foxp3(+) T regulatory cell levels predict miscarriage risk in newly pregnant women with a history of failure

Citation Winger EE, Reed JL. Low circulating CD4⁺ CD25⁺ Foxp3⁺ T regulatory cell levels predict miscarriage risk in newly pregnant women with a history of failure. Am J Reprod Immunol 2011; 66: 320–328 Problem The purpose of this study was to determine whether quantification of peripheral blood Treg cell levels could be used as an indicator of miscarriage risk in newly pregnant women with a history of immunologic reproductive failure. Method of Study Fifty‐four pregnant women with a history of immunologic infertility and/or pregnancy loss were retrospectively evaluated (mean age: 36.7 ± 4.9 years, 2.8 ± 2.5 previous miscarriages; 1.5 ± 1.9 previous IVF failures). Twenty‐three of these women experienced another first trimester miscarriage, and 31 of these women continued their current pregnancies past 12 weeks (‘pregnancy success’). The following immunologic parameters were assessed in the first trimester: NK cell 50:1 cytotoxicity, CD56⁺ 16⁺ CD3^? (NK), CD56⁺ CD3⁺ (NKT), TNFα/IL‐10, IFNγ/IL‐10, CD4⁺ CD25^?Foxp3⁺, total CD4⁺ Foxp3⁺ (CD4⁺ CD25⁺ Foxp3 plus CD25^? Foxp3⁺), and CD4⁺ CD25⁺ Foxp3⁺ levels. Results Patients with successful ongoing pregnancies experienced a mean (CD4⁺ CD25⁺ Foxp3⁺) ‘Treg’ level of 0.72 ± 0.52%, while those that miscarried in the first trimester experienced a mean Treg level of 0.37 ± 0.29% (P = 0.005). Markers not significantly different between the loss and success groups were NK 50:1 cytotoxicity (P = 0.63), CD56⁺ 16⁺ 3⁺ NK cells (P = 0.63), CD56⁺ 3⁺ NKT (P = 0.30), TNFα⁺IL‐10⁺(P = 0.13), IFNg⁺IL‐10⁺ (P = 0.63), and CD4⁺ 25^? Foxp3⁺ cells (P = 0.10), although total CD4⁺ Foxp3⁺ levels remained significant (P = 0.02) and CD4⁺ 25⁺ Foxp3⁺ showed the most significant difference (P = 0.005). Mean day of blood draw was 49.2 ± 36.1 days pregnant (median 39.0 days). In addition, patients with a low Treg level (<0.7%) in the first trimester experienced a significantly lower ongoing pregnancy rate than those with a higher Treg level (>0.7%) in the first trimester [44% (15/34) versus 80% (16/20); P = 0.01]. Of the 18 successful pregnancies with sequential Treg results, 85% (11/13) showed a T‐regulatory‐cell‐level increase (mean Treg change 0.33 ± 0.32), while only 40% (2/5) of the failed pregnancies showed a Treg increase (mean Treg change ?0.08 ± 0.28; P = 0.02). Conclusions From these data, we propose that CD4⁺ CD25⁺ Foxp3⁺ T regulatory cells may serve as a superior pregnancy marker for assessing miscarriage risk in newly pregnant women. Larger follow‐up studies are needed for confirmation.     

Circulating Toll‐like receptor (TLR) 2, TLR4, and regulatory T cells in patients with chronic hepatitis C

Wang J‐P, Zhang Y, Wei X, Li J, Nan X‐P, Yu H‐T, Li Y, Wang P‐Z, Bai X‐F. Circulating Toll‐like receptor (TLR) 2, TLR4, and regulatory T cells in patients with chronic hepatitis C. APMIS 2010; 118: 261–70. The mechanism of hepatitis C virus (HCV) involvement in innate immune responses and immune modulation has not been well characterized. In the present work, we studied Toll‐like receptor (TLR) 2 and TLR4, which were recently recognized as the important components of innate immunity, as well as CD4⁺ CD25⁺ CD127^low/? regulatory T cells (Tregs), which actively suppress pathological and physiological immune response during HCV infection. The study involved 31 chronic hepatitis C patients and 20 healthy controls. TLR2 and TLR4 expression in peripheral blood monocytes and the number of Tregs were examined by flow cytometric analysis. Overexpression of TLR2 and TLR4 was found in chronic hepatitis C patients as compared with controls. Furthermore, increased cytokine production, including that of β‐interferon, tumor necrosis factor‐α, interleukin (IL)‐6, and IL‐8, was observed in peripheral blood mononuclear cells from chronic hepatitis C patients after challenge with TLR2 and TLR4 agonists. The number of Tregs was significantly higher in chronic hepatitis C patients and the increased Tregs were associated with HCV genotype 1b. In vitro studies demonstrated that circulating Tregs suppress T‐cell responses in chronic hepatitis C patients. Significant correlations were found between the viral load and Treg number and between TLR2 and TLR4 level in chronic hepatitis C patients. Taken together with other published data, these results suggest that TLR2, TLR4, and Tregs correlate closely with chronic HCV infection.     

Differential Cytokine Expression and Regulatory Cells in Patients with Primary and Secondary Sjögren's Syndrome

Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration of the salivary and lacrimal glands. The aim of the study was to characterize and compare the presence of diverse cytokines and regulatory T and B cells in lip minor salivary gland (MSG) biopsies from patients with primary Sjögren's syndrome (pSS), secondary SS (sSS), and patients with connective tissue disease (CTD) without (w/o) SS. We included samples of MSG from 15 pSS, 24 sSS (six scleroderma, nine rheumatoid arthritis and nine lupus patients) and 15 patients with CTD w/o SS. Tissues were examined by an indirect immunoperoxidase technique (goat polyclonal anti‐human IL‐19, goat polyclonal anti‐human IL‐22 or mouse monoclonal anti‐human IL‐24). To determine the subpopulation of CD4⁺/IL‐17A⁺‐, CD4⁺/IL‐4⁺‐, CD4⁺/IFN‐?⁺‐expressing T cells, CD25⁺/Foxp3⁺ Treg cells and CD20⁺/IL‐10⁺‐producing B cell subset, a double‐staining procedure was performed. We estimated the mean percentage of positively staining cells in two fields per sample. CD4⁺/IFN‐?⁺, CD4⁺/IL‐4⁺ and IL‐22⁺ cell percentages were elevated in both SS varieties; however, the cells were more prevalent in pSS. Patients with pSS had a high number of CD4⁺/IL‐17A⁺ and IL‐19⁺ T cells and a lower percentage of IL‐24⁺ cells (P < 0.05). The Treg and IL‐10‐producing B cells were increased in pSS (P < 0.05). Concluding, in our patients, a pro‐inflammatory and regulatory balance coexists in SS, being both responses more intense in pSS. The explanation of these differences may be related to disease activity, disease duration and treatment.