CXCR5+ CD8+ T cells could induce the death of tumor cells in HBV-related hepatocellular carcinoma

The follicular CXCR5⁺ CD8⁺ T cells have recently emerged as a critical cell type in mediating peripheral tolerance as well as antiviral immune responses during chronic infections. In this study, we investigated the function of CXCR5⁺ CD8⁺ T cells in HBV-related hepatocellular carcinoma patients. Compared to CXCR5⁻ CD8⁺ T cells, CXCR5⁺ CD8⁺ T cells presented elevated PD-1 expression but reduced Tim-3 and CTLA-4 expression. Upon anti-CD3/CD28 stimulation, CXCR5⁺ CD8⁺ T cells demonstrated higher proliferation potency than CXCR5⁻ CD8⁺ T cells, especially after PD-1 blockade. CXCR5⁺ CD8⁺ T cells also demonstrated significantly higher granzyme B synthesis and release, as well as higher level of degranulation. Tumor cells were more readily eliminated by CXCR5⁺ CD8⁺ T cells than by CXCR5⁻ CD8⁺ T cells. Interestingly, we found that B cells were more resistant to CXCR5⁺ CD8⁺ T cell-mediated killing than tumor cells, possibly through IL-10-mediated protection. In addition, the CXCR5⁺ CD8⁺ T cell-mediated cytotoxic effects on tumor cells could be significantly enhanced by PD-L1 blockade. Together, we presented that in patients with in HBV-related hepatocellular carcinoma, CXCR5⁺ CD8⁺ T cells could mediate tumor cell death more potently than the CXCR5⁻ CD8⁺ T cells in vitro while the autologous B cells were protected.     

Circulating follicular helper T cells presented distinctively different responses toward bacterial antigens in primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic and progressive cholestatic liver disease with unknown causes. The initiation of PBC is associated with bacterial infections and abnormal immune correlates, such as the presence of self-reactive anti-mitochondrial antibodies and shifted balance of T cell subsets. In particular, the CD4⁺ CXCR5⁺ follicular helper T (Tfh) cells are highly activated in PBC patients and are significantly associated with PBC severity, but the underlying reasons are unknown. In this study, we found that the circulating CD4⁺ CXCR5⁺ T cells were enriched with the interferon (IFN)-γ-secreting Th1-subtype and the interleukin (IL)-17-secreting Th17-subtype, but not the IL-4-secreting Th2 subtype. We further demonstrated that a host of microbial motifs, including Pam3CSK4, poly(I:C), LPS, imiquimod, and CpG, could significantly stimulate IFN-γ, IL-17, and/or IL-21 from circulating CD4⁺ CXCR5⁺ T cells in PBC patients, especially in the presence of monocytes and B cells. Whole bacterial cells of Escherichia coli, Novosphingobium aromaticivorans, and Mycobacterium gordonae, could also potently stimulate IFN-γ, IL-17, and/or IL-21 production from circulating CD4⁺ CXCR5⁺ T cells. But interestingly, while the whole cell could potently stimulate circulating CD4⁺ CXCR5⁺ T cells from both healthy controls and PBC patients, the cell protein lysate could only potently stimulate circulating CD4⁺ CXCR5⁺ T cells from PBC patients, but not those from healthy controls, suggesting that circulating CD4⁺ CXCR5⁺ T cells in PBC patients had distinctive antigen-specificity from those in healthy individuals. Together, these data demonstrated that bacterial antigen stimulation is a potential source of aberrant Tfh cell activation in PBC patients.     

CXCR5+ CD8+ T cells present elevated capacity in mediating cytotoxicity toward autologous tumor cells through interleukin 10 in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is a common and aggressive subtype of non-Hodgkin's lymphomas, with limited treatment options in refractory and relapsed patients. Growing evidence supports the notion that CD8⁺ T cell immunity could be utilized to eliminate B cell lymphomas. CXCR5⁺ CD8⁺ T cell is a novel cell subtype and share CXCR5 expression with CD19⁺ tumor cells. In this study, we investigated the frequency and function of existing CXCR5⁺ CD8⁺ T cells in DLBCL patients. We found that DLBCL patients as a group demonstrated significantly higher level of CXCR5⁺ CD8⁺ T cells than healthy individuals, with huge variability in each patient. Using anti-CD3/CD28-stimulated CD8⁺ T cells as effector (E) cells and autologous CD19⁺ tumor cells as target (T) cells, at high E:T ratio, no difference between the intensities of CXCR5⁺ CD8⁺ T cell- and CXCR5⁻ CD8⁺ T cell-mediated cytotoxicity were observed. However, at intermediate and low E:T ratios, the CXCR5⁺ CD8⁺ T cells presented stronger cytotoxicity than CXCR5⁻ CD8⁺ T cells. The expressions of granzyme A, granzyme B, and perforin were significantly higher in CXCR5⁺ CD8⁺ T cells than in CXCR5⁻ CD8⁺ T cells, with no significant difference in the level of degranulation. Tumor cells in DLBCL were known to secrete high level of interleukin 10 (IL-10). We therefore blocked the IL-10/IL-10R pathway, and found that the expressions of granzyme A, granzyme B, and perforin by CXCR5⁺ CD8⁺ T cells were significantly elevated. Together, these results suggest that CXCR5⁺ CD8⁺ T cells are potential candidates of CD8⁺ T cell-based immunotherapies, could mediate elimination of autologous tumor cells in DLBCL patients, but are also susceptible to IL-10-mediated suppression.     

A higher frequency of CD4+ CXCR5+ T follicular helper cells in patients with newly diagnosed Henoch–Schönlein purpura nephritis

T follicular helper (TFH) cells play an important role in the humoral immune responses. The aim of this study was to examine the frequency of different subsets of CD4⁺ CXCR5⁺ TFH cells and B cells in patients with new-onset Henoch–Schönlein purpura nephritis (HSPN). The numbers of different subsets of CD4⁺ CXCR5⁺ TFH cells, B cells and the constituents of serum cytokines were detected in a total of 25 patients with newly diagnosed HSPN before and after treatment, and in 14 healthy controls (HC). The potential connection of these cells with the clinical characteristics in HSPN patients was analyzed. The numbers of circulating CD4⁺ CXCR5⁺, CD4⁺ CXCR5⁺ ICOS⁺ and CD4⁺ CXCR5⁺ PD-1⁺ TFH cells, CD86⁺ CD19⁺, CD38⁺ CD19⁺ B cells and serum IL-2, IL-4, IL-17A, IL-21 and IFN-γ were significantly higher in HSPN patients (p < 0.05) than in HC. Before and after treatment the numbers of CD4⁺ CXCR5⁺ TFH cells were negatively correlated with the values of eGFR (r = − 0.7162, p < 0.05; r = − 0.732, p < 0.05, respectively). Similarly the numbers of CD4⁺ CXCR5⁺ PD-1⁺ TFH cells were negatively correlated with 24-h urinary proteins (r = − 0.4013, p < 0.05; r = − 0.7857, p < 0.05, respectively), and the numbers of CD4⁺ CXCR5⁺ ICOS⁺ TFH cells were positively correlated with the levels of serum IL-21 (r = 0.5186, p < 0.05; r = 0.8503, p < 0.05, respectively) and 24-h urinary protein (r = 0.6045, p < 0.05; r = 0.833, p < 0.05, respectively) in these patients, regardless of treatment. Following treatment the numbers of CD4⁺ CXCR5⁺, CD4⁺ CXCR5⁺ PD-1⁺, and CD4⁺ CXCR5⁺ ICOS⁺ TFH cells, as well as serum levels of IL-21 were significantly reduced, however IL-4 levels were noticeably increased (p < 0.05). A higher frequency of circulating CD4⁺ CXCR5⁺ TFH cells existed in patients with HSPN and may be a viable therapeutic target.     

CD4+ B220+ TCRγδ+ T cells produce IL-17 in lupus-prone MRL/lpr mice

Systemic lupus erythematosus is an autoimmune disease with comprehensive immune cell disorders. Recent studies suggested that pro-inflammatory cytokine IL-17 plays important role in lupus, leaving the cellular sources and their pathogenic and physiologic characters largely unknown. In the current study, by using lupus-prone MRL/lpr mice, we demonstrated that Th17 response prevails in lupus disease regarding significantly accumulated serum IL-17, increased IL-17-producing splenocytes, and elevated phospho-STAT3 in CD4⁺ T cells. Intracellular staining revealed that unusual CD4⁺ B220⁺ T cells are major IL-17-producing cells, whereas conventional CD4⁺ B220⁻ T cells are major IFN-γ-producing cells. Subsequent studies showed that CD4⁺ B220⁺ cells contains both αβ and γδ T cells in the spleen and thymus of MRL/lpr mice. Further study showed that around 60% of γδ T cells in MRL/lpr mice co-express both B220 and CD4 on their surface, and are the major RORγt⁺ cells in MRL/lpr mice. Finally, CD4⁺ B220⁺ T cells alone do not proliferate, but could enhance the proliferation and IFN-γ-production of conventional CD4⁺ B220⁻ T cells. Our findings suggest the pathogenic role of unusual CD4⁺ B220⁺ T cells in lupus disease in MRL/lpr mice according to their IL-17-producing ability and stimulatory function for conventional CD4⁺ B220⁻ T cells.     

PD-1 regulates CXCR5+ CD4 T cell-mediated proinflammatory functions in non-small cell lung cancer patients

PD-1 inhibitors have been used to revive exhausted T cell responses in non-small cell lung cancer (NSCLC) and other malignancies. CXCR5⁺ T follicular helper (Tfh) cells are characterized by constitutive high PD-1 expression and have been associated with the formation of tertiary lymphoid structures and implicated in antitumor immunity. In this study, we investigated the effect of PD-1 and PD-1 inhibition on CXCR5⁺ CD4 T cells. Data showed that CXCR5⁺ CD4 T cells in both healthy subjects and NSCLC patients presented markedly higher PD-1 expression than CXCR5⁻ CD4 T cells. Both CXCR5⁻ and CXCR5⁺ CD4 T cells from NSCLC patients presented higher PD-1 expression than their counterparts in healthy subjects. PD-1⁺ CXCR5⁺ CD4 T cells were functional, could express IL-21, IL-10, and CXCL13 upon stimulation, demonstrated auxiliary effects toward CD8 T cell-mediated IFN-γ production and proliferation, and promoted IgM and IgG production. However, the potency of PD-1⁺ CXCR5⁺ CD4 T cells was lower than the potency of PD-1⁻ CXCR5⁺ CD4 T cells. PD-1 blocking could significantly enhance the effector functions of PD-1⁺ CXCR5⁺ CD4 T cells. Overall, this study demonstrated that PD-1⁺ CXCR5⁺ CD4 T cells could promote CD8 T cell and B cell inflammation and could be modulated by PD-1 inhibition.     

Th9 cells promote antitumor immunity via IL-9 and IL-21 and demonstrate atypical cytokine expression in breast cancer

Breast cancer is a major cause of cancer-related death in women. Antitumor T cell responses play critical therapeutic roles, including direct cytotoxicity mediated by CD8⁺ T cells and immunomodulatory roles mediated by CD4⁺ T cells. The IL-9-expressing Th9 cells are recently found to present antitumor immunity in melanoma and lung adenocarcinoma. In this study, we found that IL-9 expression in the serum and in circulating CD4⁺ T cells were significantly upregulated in breast cancer patients compared to healthy controls. The IL-9-expressing Th9 cells were enriched in the CCR4⁻ CCR6⁻ CXCR3⁻ subset. Upon TCR stimulation, this subset also presented potent IL-10 and IL-21 expression in addition to IL-9 expression. CCR4⁻ CCR6⁻ CXCR3⁻ CD4⁺ T cells also assisted in the killing of autologous tumor cells by CD8⁺ T cells, but did not initiate cytotoxicity by themselves. This enhancement in CD8⁺ T cell-mediated cytotoxicity was dependent on IL-9 as well as on IL-21. Interestingly, the tumor-infiltrating Th9 cells presented comparable IL-9, reduced IL-10, and elevated IL-21 expression compared with their counterparts in the peripheral blood. Together, these results demonstrated that IL-9-expressing Th9 cells were upregulated in breast cancer patients and potentially possessed antitumor roles by enhancing CD8⁺ T cell-mediated cytotoxicity.     

CD163+ M2-type tumor-associated macrophage support the suppression of tumor-infiltrating T cells in osteosarcoma

Osteosarcoma is one of the most common childhood cancers with high numbers of cancer-related deaths. Progress in conventional therapies is showing limited improvement. An adaptive T cell-based immunotherapy represents a promising new therapeutic option, but to improve its efficacy, regulatory mechanisms in osteosarcoma need further elucidation. Here, to evaluate the regulatory effect of tumor microenvironment of T cells in osteosarcoma, we examined the peripheral blood (PB) and tumor infiltrating (TI) T cells, and their correlations with PB and tumor immune characteristics. We found that TI T cells contained significantly higher levels of TIM-3⁺ PD-1⁻ and TIM-3⁺ PD-1⁺ cells than their PB counterparts. Similar to that in chronic HIV and HCV infections, these TIM-3⁺ PD-1⁻ and TIM-3⁺ PD-1⁺ T cells presented reduced proliferation and proinflammatory cytokine secretion in response to stimulation. Presence of M2-type (CD163⁺) macrophages exacerbated T cell immunosuppression, since frequencies of CD163⁺ tumor-associated macrophages were directly correlated with the frequencies of suppressed TIM-3⁺ PD-1⁺ T cells. Moreover, depletion of CD163⁺ macrophages significantly improved T cell proliferation and proinflammatory cytokine production. Overall, our data presented an intratumoral T cell-specific immunosuppression that was amplified by M2-type tumor-associated macrophages.     

The role of regulatory B cells (Bregs) in the Tregs-amplifying effect of Sirolimus

Sirolimus can significantly amplify regulatory T cells (Tregs) in vivo and in vitro, but the specific mechanism of this has not been well documented. The role of regulatory B cells (Bregs) in the Tregs-amplifying effect of Sirolimus was investigated in peripheral blood mononuclear cells (PBMCs) in vitro in this study. The results showed that the percentages of both CD19 + CD24 + CD38 + TGF-β1 + Bregs and CD19 + CD24 + CD38 + IL-10 + Bregs to B cells were elevated by Sirolimus in PBMCs including B cells. Sirolimus significantly enhances the cytokine production of transforming growth factor-β1 (TGF-β1) and interleukin-10 (IL-10) in PBMCs with B cells, and the enhancement significantly decreased in PBMCs without B cells. The percentage of CD4 + CD25 + Foxp3 + Tregs to T cells was also elevated by Sirolimus in PBMCs including B cells. The elevation of Tregs percentage decreased in PBMCs without B cells and recovered when additional TGF-β1 and IL-10 were added. The amplification of Tregs by Sirolimus was partially inhibited when either TGF-β1 or IL-10 was neutralized, and it even disappeared when these two cytokines were both neutralized. These results indicate that Sirolimus can amplify Bregs and Tregs in PBMCs in vitro, and Bregs may be the why Sirolimus amplifies Tregs.     

Influence of anticancer agents on cell survival,proliferation, and CD4+CD25+Foxp3+ regulatory T cell-frequency in human peripheral-blood mononuclear cells activated by T cell-mitogen

Many anticancer agents currently used are considered to be cytotoxic not only to cancer cells but also to functional immune cells. To learn more about the immunosuppressive adverse influence of chemotherapeutic drugs in cancer chemotherapy, we examined the effects of arsenic trioxide, dacarbazine, 5-fluorouracil, and methotrexate on the survival, proliferation, cytokine production, and CD4⁺CD25⁺Foxp3⁺ regulatory T (Treg) cell-frequency in human peripheral blood mononuclear cells (PBMCs) activated by T cell mitogen in vitro. Arsenic trioxide, dacarbazine, and 5-fluorouracil increased trypan-blue stained (dead) cell rates and suppressed the mitogen-activated proliferation of PBMCs significantly at 1–100 μM (p < 0.05). Methotrexate also significantly increased the percentages of dead cells and suppressed the mitogen-activated PBMC-proliferation at concentrations of more than 0.05 μM (p < 0.01). Arsenic trioxide significantly inhibited the production of interferon γ, interleukin (IL)-4, -6, and -10 from the activated PBMCs at 5 μM (p < 0.05). In contrast, the anticancer agents significantly increased Treg cell-frequency in the activated PBMCs at concentrations of more than 0.1 μM for methotrexate, 5 μM for arsenic trioxide and 5-fluorouracil, and 50 μM for dacarbazine, respectively (p < 0.05). These agents did not significantly influence the production of transforming growth factor (TGF) β from the activated PBMCs at a concentration range of 0.05–50 μM. Our data suggest that the anticancer agents: arsenic trioxide, dacarbazine, 5-fluorouracil, and methotrexate attenuate T cell mediated immunity by not only inhibiting the proliferative response of T cells but by also increasing the frequency of Treg cells, which may result in the suppression of the effector T cell function.     

APL-1, an altered peptide ligand derived from human heat-shock protein 60, selectively induces apoptosis in activated CD4 + CD25 + T cells from peripheral blood of rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a chronic T-cell mediated autoimmune disease that affects primarily the joints. The induction of immune tolerance through antigen-specific therapies for the blockade of pathogenic CD4 + T cells constitutes a current focus of research. In this focus it is attempted to simultaneously activate multiple regulatory mechanisms, such as: apoptosis and regulatory T cells (Tregs). APL-1 is an altered peptide ligand derived from a novel CD4 + T-cell epitope of human heat-shock protein of 60 kDa, an autoantigen involved in the pathogenesis of RA. Previously, we have reported that APL-1 induces CD4 + CD25^highFoxp3 + Tregs in several systems. Here, we investigated the ability of APL-1 in inducing apoptosis in PBMCs from RA patients, who were classified as active or inactive according to their DAS28 score. APL-1 decreased the viability of PBMCs from active but not from inactive patients. DNA fragmentation assays and typical morphological features clearly demonstrated that APL-1 induced apoptosis in these cells. Activated CD4 + CD25 + T cells but not resting CD4 + CD25 − T cells were identified as targets of APL-1. Furthermore, CD4 + T-cell responses to APL-1 were found to be dependent on antigen presentation via the HLA-DR molecule. Thus, APL-1 is a regulatory CD4 + T cell epitope which might modulate inflammatory immune responses in PBMCs from RA patients by inducing CD4 + CD25^highFoxp3 + Tregs and apoptosis in activated CD4 + T cells. These results support further investigation of this candidate drug for the treatment of RA.     

Alloantigen specific T regulatory cells in transplant tolerance

CD4⁺CD25⁺Foxp3⁺T cells are regulatory/suppressor cells (Treg) that include non-antigen(Ag)-specific as well as Ag-specific Tregs. How non-Ag-specific naïve CD4⁺CD25⁺Treg develop into specific Tregs is unknown. We have studied DA rats tolerant to fully allogeneic PVG cardiac grafts that survived with out immunosuppression for over 100 days and identified the cellular basis of alloantigen specific tolerance. Key observations from our studies will be reviewed including how CD4⁺CD25⁺Tregs were first identified and the cytokine dependence of CD4⁺T cells that transfer alloantigen specific transplant tolerance which died in culture unless stimulated with both cytokine rich ConA supernatant and specific donor alloantigen. Both the tolerant CD4⁺CD25⁺ and CD4⁺CD25⁻ T cell populations are required to transfer tolerance, yet alone the CD4⁺CD25⁻ T cell effect rejection. Tolerance transfer occurs with a low ratio of CD4⁺CD25⁺T cells (< 1:10), whereas to induce tolerance with naive CD4⁺CD25⁺T cells requires both a ratio of > 1:1 and is not alloantigen specific.Recent findings on how naïve CD4⁺CD25⁺T cells developed into two separated pathways of alloantigen specific Tregs, by culturing them with alloAg with either IL-2 or IL-4 and donor alloantigen are described. IL-2 enhances IFN-γR and IL-5 mRNA while IL-4 induced a reciprocal profile with de novo IL-5Rα and increased IFN-γ mRNA expression. Both IL-2 and IL-4 alloactivated CD4⁺CD25⁺Tregs within 3–4 days of culture can induce alloantigen specific tolerance at ratios of 1:10. Long term, CD4⁺CD25⁺T cells from tolerant hosts given IL-2 cultured cells have increased IL-5 and IFN-γR mRNA; whereas hosts given IL-4 cultured cells had enhanced IL-5Rα mRNA expression and IL-5 enhanced their proliferation to donor but not third party alloAg.These findings suggest that Th1 and Th2 responses activate two pathways of alloantigen specific Tregs that can mediate transplant tolerance but are dependent upon cytokines produced by ongoing Th1 and/or Th2 immune responses.     

Compact bone-derived mesenchymal stem cells attenuate nonalcoholic steatohepatitis in a mouse model by modulation of CD4 cells differentiation

Increasing evidence has accrued which indicates that mesenchymal stem cells (MSCs) have a potential clinical value in the treatment of certain diseases. Globally, nonalcoholic steatohepatitis (NASH) is a widespread disorder. In the present study, MSCs were isolated successfully from compact bone and a mouse model of NASH was established as achieved with use of a methionine-choline deficient (MCD) diet. Compact bone-derived MSCs transplantation reduced MCD diet-induced weight loss, hepatic lipid peroxidation, steatosis, ballooning, lobular inflammation and fibrogenesis. It was shown that MSCs treatment hampered MCD diet-induced proliferation of CD4⁺ IFN-γ⁺ and CD4⁺ IL-6⁺ T spleen cells. In addition, CD4⁺ IL-17⁺ lymphocytes that associated with anti-inflammation show little change in MCD as well as in MCD + MSCs splenocytes. We conclude that MSCs may have a potential clinical value upon NASH, through their capacity to suppress activation of CD4⁺ IFN-γ⁺ and CD4⁺ IL-6⁺ lymphocytes.     

The CD4/CD8 ratio is associated with coronary artery disease (CAD) in elderly Chinese patients

Objective: The aim of this study was to investigate the relationship between number of circulating T cells and coronary artery disease (CAD) in an elderly Chinese population.Methods: A total of 295 elderly inpatients (age ≥ 60) were included in this cross-sectional study. Their clinical and biochemical characteristics were recorded. Patients were divided to two groups: control patients and CAD patients. The risk factors of CAD were explored by binary logistic regression analysis.Results: Compared with control patients, the ratio of CD4 to CD8 T cells was significantly increased in CAD patients. There was no difference in the number of CD3, CD4, and CD8 T cells between the two groups. Multiple logistic regression analysis showed that CAD was independently associated with age, gender, body mass index (BMI), systolic blood pressure (SBP), chronic heart failure (CHF) and the CD4/CD8 ratio. In addition, after adjusting for different clinical parameters (including gender, age, CHF, hypertension, arrhythmia, SBP, and BMI), the risk of CAD was significantly increased in patients with a CD4/CD8 ratio > 1.5.Conclusions: There was a strong and independent association between the ratio of CD4/CD8 and CAD in elderly Chinese population.     

Mesenchymal stem cells upregulate Treg cells via sHLA-G in SLE patients

BackgroundSoluble human leukocyte antigen-G (sHLA-G) is a non-classical HLA class I molecule, exhibiting strong immunosuppressive properties by inducing the differentiation of T regulatory cells (Treg). Mesenchymal stem cells (MSCs) transplantation alleviates disease progression in systemic lupus erythematosus (SLE) patients. However, the underlying mechanisms are largely unknown.ObjectivesTo explore whether sHLA-G is involved in upregulating effects of MSCs on Treg, which contributes to therapeutic effects of MSCs transplantation in SLE.MethodsThe serum sHLA-G levels of SLE patients and healthy controls were detected by ELISA. The percentages of peripheral blood CD4 + ILT2 +, CD8 + ILT2 +, CD19 + ILT2 + cells and Treg cells were examined by flow cytometry. Ten patients with active SLE, refractory to conventional therapies, were infused with umbilical cord derived MSCs (UC-MSCs) and serum sHLA-G was measured 24 h and 1 month after infusion. The mice were divided into three groups: C57BL/6 mice, B6.MRL-Fas^lpr mice infused with phosphate buffer saline (PBS), and B6.MRL-Fas^lpr mice infused with bone marrow MSCs (BM-MSCs). Then, the concentrations of serum Qa-2 were detected. Peripheral blood mononuclear cells (PBMCs) were isolated from SLE patients and co-cultured with UC-MSCs for 3 days at different ratios (50:1, 10:1, and 2:1) with or without HLA-G antibody, and the frequencies of CD4 + CD25 + Foxp3 + T cells were then determined by flow cytometry.ResultsThe concentrations of serum sHLA-G were comparable between SLE patients and healthy controls. However, there was a negative correlation between sHLA-G levels and SLE disease activity index (SLEDAI) scores in active SLE patients (SLEDAI > 4). We found that serum sHLA-G levels were negatively correlated with blood urea nitrogen, serum creatinine and 24-hour urine protein in SLE patients. The sHLA-G levels were significantly lower in SLE patients with renal involvement than those without renal involvement. The expression of ILT2 on CD4 + T cells from SLE patients decreased significantly compared to that of healthy controls. A positive correlation between the frequencies of Treg and CD4 + ILT2 + T cells was found in SLE patients. The levels of sHLA-G increased 24 h post UC-MSCs transplantation. The concentrations of Qa-2 in BM-MSCs transplanted mice were significantly higher than those of control group. In vitro studies showed that MSCs increased the frequency of Treg cells in SLE patients in a dose-dependent manner, which was partly abrogated by the anti-HLA-G antibody.ConclusionsOur results suggested that MSCs may alleviate SLE through upregulating Treg cells, which was partly dependent on sHLA-G.     

Erythropoietin exerts direct immunomodulatory effects on the cytokine production by activated human T-lymphocytes

The effect of erythropoietin-β (Epo-β) on the functional profile of activated human T-lymphocytes remains largely unknown, which hinders clinical application of Epo as an immunomodulatory agent. We studied the direct impact of Epo on the activation status of human T lymphocytes following activation by particles loaded with antibodies (Abs) against human CD2, CD3, and CD28. T cell activation was assessed by the surface expression of CD38 activation marker. Epo did not significantly affect activation status of both CD4⁺ and CD4⁻ T cells, as well as of naive (CD45RA⁺ CD197⁺), central memory (CD45RA⁻ CD197⁺), effector memory (CD45RA⁻ CD197⁻), and terminally-differentiated (CD45RA⁺ CD197⁻) T cells. However, Epo markedly augmented production of IL-2, IL-4 and IL10 by activated T cells with concomitant reduction in IFN-γ secretion. Taken together, our data showed that Epo could directly down-regulate pro-inflammatory T cell responses without affecting T cell activation status.     

P-glycoprotein function in peripheral T lymphocyte subsets of myasthenia gravis patients: Clinical implications and influence of glucocorticoid administration

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder with a chronic clinical course that requires long-term glucocorticoid (GC) therapy. A drug efflux pump, P-glycoprotein (P-gp), actively transports GC out of target cells, thereby reducing its efficacy. We evaluated the P-gp function of peripheral-blood mononuclear cells in 59 MG patients. P-gp function was estimated from a decrease in fluorescent P-gp substrate Rhodamine 123 and its inhibition by the conformation-sensitive UIC2 monoclonal antibody. P-gp function on CD8⁺ T cells in 21 MG patients having experienced GC therapy was higher than that in 19 MG patients having no history of GC therapy (p = 0.026). There was a significant correlation between P-gp function in CD3⁺ (r = 0.55, p = 0.014) or CD4⁺ (r = 0.48, p = 0.034) T cells and the total dose of prednisolone for treatment. P-gp function on CD4⁺ T cells in MG patients who showed low responses to prednisolone therapy (n = 8) was higher than that in patients who showed relatively high responses to prednisolone therapy (n = 10) (p = 0.045). These results suggest that higher P-glycoprotein activity on CD3⁺ or CD4⁺ cells necessitated treatment with higher steroid doses in order to achieve a clinical response. The measurement of P-gp function on CD4⁺ T cells is useful in the assessment of clinical response to GC therapy.     

Enhanced effect of κ-carrageenan on TNBS-induced inflammation in mice

BackgroundAs a sulfated polysaccharide, carrageenan has been widely used as common food additive.MethodsIn the present study, we investigated the effects of κ-carrageenan on TNBS-induced gut inflammation in mice. BALB/c mice were pretreated with κ-carrageenan for 14 days prior to the administration of TNBS.ResultsOur results showed that κ-carrageenan pretreatment aggravated the loss of body weight and further increased the mortality rate. Histological and morphological analyses revealed that the TNBS-induced colonic inflammation was deteriorated by the κ-carrageenan administration. The ratio of CD4⁺ CD25⁺ CD127dim/CD4⁺ of the κ-carrageenan + TNBS groups was significantly lower than that of the TNBS group. The expression of IL-2, TNF-α and IL-6 was significantly increased, whereas the expression of IL-10 was significantly decreased in the κ-carrageenan + TNBS groups. In addition, κ-carrageenan, together with TNBS, decreased the enzyme activity of SOD and GSH-px and up-regulated the expression of TLR4, NF-κB, p-ERK, p-JNK, p-Jun., IL-8 and MDA in the colonic mucosa.Conclusionsκ-Carrageenan aggravated the TNBS-induced intestinal inflammation, and such an effect could be associated with the oxidative stress and activation of TLR4-NF-κB and MAPK/ERK1/2 pathway.     

Gabapentin-induced changes of plasma cortisol level and immune status in hysterectomized women

AimWe have examined the effects of gabapentin (GBP) on stress-related changes of cortisol and catecholamines in patients who underwent hysterectomy because of uterine fibrinoids. Additionally, we have observed the effect of GBP on the immune status in the acute stress response to surgery.MethodsSixty patients scheduled for an abdominal hysterectomy were randomly assigned to the GBP administration 1 h before surgery (n = 30 pts), or to the placebo group (n = 30 pts). Blood samples were collected before and 24 h after the surgery. The intensity of pain was assessed by a visual analogue scale (VAS) every 8 h at rest. Immunomodulatory effects of GBP were determined by flow cytometry. We followed the total proportion of CD3⁺ lymphocytes, CD3⁺CD4⁺, CD3⁺CD8⁺, CD19⁺ B lymphocytes, CD16⁺CD56⁺CD3⁻NK cells and CD16⁺CD56⁺CD3⁺ NKT cells before and 24 h after hysterectomy. The plasma cortisol and catecholamines concentration was used to estimate the level of the stress response.ResultsVAS pain score at rest was significantly lower in the GBP group than in the placebo group (P = 0.003). Application of GBP significantly decreased the plasma cortisol level 24 h after the operation in comparison to the placebo group (P < 0,001). We found significant positive correlation between the VAS pain score and concentration of cortisol in all patients (P = 0.025). GBP reduced the concentration of catecholamines (p < 0.05). The proportion of CD3⁺ (P = 0.027) and CD3⁺CD4⁺cells (P = 0.006) was significantly lower in the GBP group 24 h after operation, while the contribution of CD19⁺ (P = 0.033) was significantly higher.ConclusionPreoperative administration of GBP reduced the pain scores at rest in patients at 0, 16 and 24 h after abdominal hysterectomy. Additionally, GBP reduced the stress response and changed immune parameters in the reaction to surgery.     

Astilbin inhibits Th17 cell differentiation and ameliorates imiquimod-induced psoriasis-like skin lesions in BALB/c mice via Jak3/Stat3 signaling pathway

The flavonoid astilbin is the major active component extracted from the rhizome of Smilax glabra, which has been widely used in China to treat inflammatory and autoimmune diseases, Psoriasis is a common chronic inflammatory disease in which T helper 17 (Th17) cells play an important role, provoking inflammation. We employed an imiquimod (IMQ)-induced psoriasis-like mouse model to investigate the effect of astilbin in inflammation. Mice were administered 25 to 50 mg/kg astilbin. Inflammation of psoriasis-like lesions was assessed by histology, circulating levels of T cells were assessed by flow cytometry and cytokines by bead-based immunoassay. Jak/Stat3 in isolated T cells was assessed by Western blotting and RORγt expression was assessed by RT-PCR. Administration of astilbin ameliorated IMQ-induced keratinocyte proliferation, infiltration of CD3 + cells to psoriatic lesions and ameliorated elevations in circulating CD4 + and CD8 + T cells and inflammatory cytokines (IL-17A, TNF-α, IL-6, IFN-γ and IL-2). In vitro, astilbin inhibited Th17 cell differentiation and IL-17 secretion of isolated T cells, and inhibited Jak/Stat3 signaling in Th17 cells, while up-regulating Stat3 inhibitor SCOSE3 expression in psoriatic lesions. Thus, astilbin likely alleviates psoriasis-like skin lesions by inhibiting Th17 related inflammation. Astilbin represents as an interesting candidate drug for immunoregulation of psoriasis.