Follicular Helper T Cells， Psoriasis， and Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Follicular helper T （Tfh） cells are a newly discovered subset of CD4+ T cells. As reported， abnormalities in their development， differentiation， and function are closely related to the occurrence of autoimmune diseases. Psoriasis is an autoimmune skin disease and it is intractable with a prolonged course. At present， it is generally believed that immune imbalance mediated by T cells is the core mechanism of the pathogenesis of psoriasis. In the context of this mechanism， Tfh cells are associated with psoriasis， and their cellular level and abnormal expression of related candidates can promote the occurrence of psoriasis. In terms of treatment， Chinese medicine， by virtue of the characteristics of wide application and low price， serves as a good complementary and alternative treatment option for psoriasis. As confirmed by previous findings， some active ingredients or preparations of Chinese medicine used in the treatment of psoriasis can also intervene in and regulate the immune response mediated by Tfh cells and the related candidates. Based on the research reports and experimental data， the present study reviewed the research progress from the differentiation of Tfh cells， the relationship between Tfh cells and psoriasis， and the intervention and regulation of Tfh cells and related molecules by Chinese medicine， which is expected to provide certain theoretical support and references for the determination of new strategies for psoriasis treatment and research in related fields.

Immunomodulatory mechanism of interleukin-7 receptor α antibody attenuating renal injury in MRL/lpr lupus mice / 中华肾脏病杂志

Objective:To investigate the effect of interleukin (IL)-7 receptor α (IL-7Rα) antibody on the immune inflammation and renal injury in MRL/lpr lupus mice.Methods:Fifteen 3-4-week-old female MRL/lpr lupus mice (specific pathogen free) weighing 15-16 g were bred to 14-week-old and randomly divided into three groups: IL-7Rα antibody intervention group, isotype antibody (positive control) group and normal saline (negative control) group. The mice in the threc groups were intraperitoneally injected with IL-7Rα antibody, isotype antibody and normal saline respectively, with 100 μg three times a week for 4 weeks. At the age of 18-week old, the mice were sacrificed. Twenty-four-hour urinary protein was detected by Coomassie brilliant blue method, serum creatinine was detected by peroxidase method, and the expression of autoantibody (anti-double strand DNA antibody) and inflammatory factors such as tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IL-21 was detected by enzyme-linked immunosorbent assay method. Renal pathology was detected by PAS and Sirius red staining, and CD3 and F4/80 in renal tissues were detected by immunohistochemistry method. Regulatory T cells, follicullar helper T cells (Tfh) and follicular regulatory T cells (Tfr) were detected by flow cytometry.Results:The 24-hour urinary protein, serum creatinine, serum anti-double strand DNA antibody and serum IFN-γ and IL-21 in the IL-7Rα antibody intervention group were significantly lower than those in the control groups (all P<0.01). However, there was no significant difference in serum TNF-α among the three groups ( F=0.39, P>0.05). The positive infiltrating cells of CD3 and F4/F80, and the ratio of type Ⅰ/Ⅲ collagen fibers ( F=41.11, P<0.01) of renal tissues in the IL-7Rα antibody intervention group were lower than those in the other two groups. Compared with the control groups, the ratio of regulatory T cells (CD4 +CD25 +Foxp3 +)/effector T cells (CD4 +CD25 +) in blood of IL-7Rα antibody intervention group increased ( F=21.64, P<0.01), while the ratio of Tfr (CD4 +CXCR5 +Foxp3 +)/Tfh (CD4 +CXCR5 +) in peripheral blood and spleen increased ( F=38.95, P<0.01; F=12.90, P<0.01). Conclusion:IL-7Rα antibody can reduce the production of autoantibodies such as anti-double strand DNA antibody and inflammatory factors by increasing the ratio of regulatory T cells and Tfr/Tfh, thus alleviating immune inflammation and renal damage in MRL/lpr lupus mice.

Advances on follicular helper T cells in patients with hepatitis B virus infection / 中华临床感染病杂志

Hepatitis B virus (HBV) infection is a major global public health problem. Persistent HBV infection is prone to develop chronic hepatitis B (CHB), and CHB is closely related to the development of liver fibrosis and hepatocellular carcinoma. High-affinity specific anti-HBs are essential for the control of HBV infection, while the antibody production is closely related to follicular helper T (Tfh) cells. Tfh cells can help B cells differentiate into plasma cells to produce specific antibodies to control virus infection. This article reviews the latest research progress of Tfh cells in HBV infection to provide information of new strategies for the prevention and treatment of HBV.

Therapeutic effect of gene silencing peptidyl arginine deaminase 4 on pulmonary interstitial lesions induced by collagen-induced arthritis mice / 北京大学学报(医学版)

OBJECTIVE@#To investigate the therapeutic effect of gene silencing peptidyl arginine deaminase 4 (PAD4) on pulmonary interstitial lesions induced by collagen-induced arthritis (CIA) mice, and possible mechanisms.@*METHODS@#A CIA mouse model was established in DBA/1 mice, followed by a tail vein injection of the virus solution prepared by the PAD4-siRNA expression vector once a week for 8 times. The mice were sacrificed at the end of the experiment. The expression of PAD4 mRNA in lungs was detected by real-time quantitative PCR (qRT-PCR). The expression of PAD4 protein was detected by tissue immunohistochemistry. Cell culture was performed by spleen tissue. Flow cytometry changes in the ratio of Tfh cells to Tfr cells were examined; lung staining was performed in the lungs to observe changes in lung pathology.@*RESULTS@#(1) Compared with the blank group, the expression of PAD4 mRNA in the lung tissue of the model group increased, the difference was statistically significant (P < 0.05). PAD4 mRNA in the lung tissue of the CIA mice after PAD4-siRNA treatment. The expression level was significantly lower than that of the model group and the negative control group, and the difference was statistically significant (P < 0.05). (2) Red fluorescence was less in the lung tissue of the blank group, while more red fluorescence was observed in the inflammatory cell infiltration area and trachea around the lung tissue of the model group and the negative control group, and the red fluorescence of the three groups after PAD4-siRNA treatment was significantly reduced; (3) Compared with the blank group, the proportion of Tfh cells in the model group increased, the difference was statistically significant (P < 0.05), the proportion of Tfh cells in spleen cells of the CIA mice after PAD4-siRNA treatment was significantly lower than that of the model group and the negative control group, the difference was statistically significant (P < 0.05); compared with the blank group, in the mouse spleen cells in the model group the proportion of Tfr cells was slightly decreased, but the difference was not statistically signifi-cant. The proportion of Tfr cells in the spleen cells of the mice increased after PAD4-siRNA treatment, but the difference was statistically significant only in the PAD4-siRNA2 group compared with the model group and the negative control group (P < 0.05); (4) The proportion of Tfh/Tfr in the spleen cells of the model group was increased, compared with the blank group, the difference was statistically significant (P < 0.05); the ratio of Tfh/Tfr in the three groups after PAD4-siRNA treatment all decreased, the difference was statistically significant (P < 0.05); (5) Compared with the blank group, the alveolar wall of the lung tissue of the model group was thickened, the inflammatory cell infiltration was increased, and the lung tissue destruction and inflammatory infiltration of the CIA mice were decreased after PAD4-siRNA treatment. The degree of reduction was reduced.@*CONCLUSION@#Gene silencing of PAD4 can reduce the proportion of Tfh cells, increase the proportion of Tfr cells, reverse the proportion of Tfh/Tfr, and reduce the degree of interstitial lesions and inflammatory infiltration of lung tissue.

The significance of follicular helper T cells and galactose-deficient IgA 1 in the pathogenesis of Henoch-Sch?nlein purpura in children / 国际儿科学杂志

Objective:To investigate the role of follicular helper T(Tfh) cells and galactose deficiency IgA 1(Gd-IgA 1) in the children that were suffering from Henoch-Sch?nlein purpura(HSP) and Henoch-Sch?nlein purpura nephritis(HSPN)and the correlation between them. Methods:According to the presence or absence of renal injury, 62 children with HSP were divided into HSP group with 32 children and HSPN group with 30 children.Twenty children who underwent physical examination at outpatients were known as the healthy control group.Flow cytometry was used to measure the proportion of Tfh(CD4 + CXCR5 + PD-1 + ) in peripheral blood.Immunoturbidimetry and ELISA were used to measure the serum levels of IgA 1 and Gd-IgA 1 respectively. Results:(1) The proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1 in both HSP group and HSPN group had significantly increased than those in healthy control group( P<0.01). Compared result of the HSPN group with HSP group, the proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1 in HSPN group were higher than that in HSP group( P<0.05). (2) In the HSPN group, the proportion of peripheral blood Tfh cells and the serum levels of Gd-IgA 1 in group of renal pathology ≥ grade Ⅲ and heavy proteinuria were significantly elevated compared with group of renal pathology < grade Ⅲ and non-heavy proteinuria(<0.01). (3) In the healthy control group, the serum levels of Gd-IgA 1 was positively correlated with the proportion of Tfh cells in peripheral blood and the serum levels of Gd-IgA 1( P<0.05). Conversely, a non-positive correlation was shown in HSP and HSPN groups( P>0.05). Conclusion:The excessive activation of Tfh cells and the serum levels of Gd-IgA 1 may be one of the pathogenesis of HSP/HSPN, the degree of increment of the two factors may be related to the activity and severity of the disease.The mechanism of Tfh cells potentially leading to an increase of Gd-IgA 1 production requires further study.

Expression of follicular helper T cells in peripheral blood of patients with hepatic echinococcosis / 中国血吸虫病防治杂志

Objective To detect the expression of follicuLar helper T cells (Tfh) and interleukin-21 (IL-21) in the peripheral blood of patients with hepatic echinococcosis and healthy controls, so as to explore the associations of Tfh and IL-21 expression with the progression of hepatic echinococcosis. Methods Fifty cases of hepatic echinococcosis and healthy controls were collected from Qinghai Provincial People's Hospital, respectively. Flow cytometry was used to detect the expression of Tfh cells in the peripheral blood of hepatic echinococcosis patients and healthy controls, and enzyme-linked immunosorbent assay (ELISA) was used to detect serum IL-21 expression in hepatic echinococcosis patients and healthy controls. The correlation between Tfh cell expression and serum IL-21 level was examined in the patients with hepatic echinococcosis. Results Flow cytometry detected a higher percentage of CD4+CXCR5+ T cells (18.49% ± 5.67% vs. 16.18% ± 4.04%, P < 0.05), CD4+CXCR5+PD-1+ T cells (4.94% ± 1.91% vs. 2.29% ± 0.79%, P < 0.05) and CD4+CXCR5+ICOS+PD-1+ T cells (30.93% ± 24.10% vs. 21.07% ± 14.25%, P < 0.05) in hepatic echinococcosis patients than in healthy controls, and no significant difference was seen in the percentage of CD4+CRCR5+ICOS+ T cells between the patients and controls (0.29% ± 0.32% vs. 0.25% ± 0.31%, P > 0.05) . The serum IL-21 level was significantly higher in the patients with hepatic echinococcosis than in healthy controls ([ 293.35 ± 2 03.65) pg/mL vs. (192.72 ± 70.09) pg/mL, P < 0.05]; however, there was no correlation between the Tfh cell expression and serum IL-21 level in patients with hepatic echinococcosis (P > 0.05). Conclusion The expression of peripheral blood Tfh cells and serum IL-21 is elevated in patients with hepatic echinococcosis, and Tfh cells and IL-21 may contribute to the progression of hepatic echinococcosis.

Enhancement of T Follicular Helper Cell-Mediated Humoral Immunity Reponses During Development of Experimental Autoimmune Myasthenia Gravis / 神经科学通报·英文版

Myasthenia gravis (MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper (Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear. Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha (AChRα) subunit (R-AChR)-induced experimental autoimmune myasthenia gravis (EAMG). This model presented mild body-weight loss 10 days after the first immunization (representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization (representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In co-cultures of Tfh cells and B cells, the number of IgG2b-secreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4/Bcl-6 T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, we hypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.

Therapeutic effects of baicalin on lupus nephritis in a lupus-prone mouse model and its regulatory role in follicular helper T cell differentiation / 中华皮肤科杂志

Objective To evaluate the therapeutic effect of baicalin on lupus nephritis in a lupusprone mouse model,and to investigate its regulatory role in the differentiation of follicular helper T (Tfh)cells.Methods Eight 12-week-old female MRL/lpr lupus-prone mice were randomly and equally divided into two groups by a random number table i.e.,baicalin group and control group intraperitoneally injected with 200 mg/kg baicalin sodium and chloride physiological solution,respectively,once every day for 4 weeks.After the end of treatment,Coomassie brilliant blue staining was performed to detect the level of 24-hour urine protein.Then,the mice were sacrificed,and the spleens were resected and weighed.Mononuclear cells were isolated from these spleens,and flow cytometry was conducted to determine the proportion of Tfh cells.Additionally,the kidneys were resected and subjected to hematoxylin and eosin (HE) staining for the evaluation of kidney impairment.Moreover,some other mononuclear cells were isolated from the spleens of the lupus-prone mice in the control group,and magnetic activated cell sorting (MACS) was performed to isolate naive CD4+ T cells,which were divided into 3 groups:blank control group receiving no treatment,induction group treated with 10 μg/L anti-interleukin (IL)-21 and anti-IL-6 antibodies and 3 μg/L anti-CD3 and anti-CD28 antibodies for 5 days,and intervention group additionally treated with 40 μmol/L baicalin for 5 days besides the above treatment.Then,50 μg/L phorbol ester,750 μg/L ionomycin and 20 mg/L brefeldin A were used to stimulate some cultured naive CD4+ T cells in the above groups.Flow cytometry was conducted to determine the proportion of CD4+CXCR5+PD-1 + cells and CD4+IL-21+ cells.Statistical analysis was carried out with SPSS20.0 software by using one-way analysis of variance (ANOVA) and student t test for the comparison of quantitative data between groups.Results The baicalin treatment could effectively improve the kidney impairment in the lupus-prone mice.Compared with the control group,the baicalin group showed significantly decreased 24-hour urine protein level ([1 416 ± 171] vs.[2 623 ± 278] μg/24 h,P =0.022),and significantly decreased proportion of Tfh cells in the spleen (12.6％ ± 2.3％ vs.40.2％ + 1.1％,P =0.005).In vitro baicalin could further inhibit the differentiation of Tfh cells.Compared with the induction group,the intervention group showed significantly decreased proportion of CD4+CXCR5+PD-1+ Tfh cells (13.3％ ± 0.8％ vs.17.6％ ± 0.9％,P =0.04) and CD4+IL-21+ cells (1.0％ ± 0.4％ vs.2.7％ ± 0.2％,P ＜ 0.01).Conclusion Baicalin can effectively ameliorate lupus nephritis,which may be associated with the inhibition of Tfh cell differentiation.

Aged Sanroque Mice Spontaneously Develop Sjögren's Syndrome-like Disease

Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disorder that affects mainly salivary and lacrimal glands, but its cause remains largely unknown. Clinical data indicating that SS occurs in a substantial proportion of patients with lupus points to common pathogenic mechanisms underlying the two diseases. To address this idea, we asked whether SS develops in the lupus-prone mouse strain sanroque (SAN). Owing to hyper-activation of follicular helper T (Tfh) cells, female SAN mice developed lupus-like symptoms at approximately 20 wk of age but there were no signs of SS at that time. However, symptoms typical of SS were evident at approximately 40 wk of age, as judged by reduced saliva flow rate, sialadenitis, and IgG deposits in the salivary glands. Increases in serum titers of SS-related autoantibodies and numbers of autoantibody-secreting cells in cervical lymph nodes (LNs) preceded the pathologic manifestations of SS and were accompanied by expansion of Tfh cells and their downstream effector cells. Thus, our results suggest that chronic dysregulation of Tfh cells in salivary gland-draining LNs is sufficient to drive the development of SS in lupus-prone mice.

Expression of follicular helper T cells in peripheral blood of patients with hepatic echinococcosis / 中国血吸虫病防治杂志

Objective To detect the expression of follicuLar helper T cells (Tfh) and interleukin-21 (IL-21) in the peripheral blood of patients with hepatic echinococcosis and healthy controls, so as to explore the associations of Tfh and IL-21 expression with the progression of hepatic echinococcosis. Methods Fifty cases of hepatic echinococcosis and healthy controls were collected from Qinghai Provincial People's Hospital, respectively. Flow cytometry was used to detect the expression of Tfh cells in the peripheral blood of hepatic echinococcosis patients and healthy controls, and enzyme-linked immunosorbent assay (ELISA) was used to detect serum IL-21 expression in hepatic echinococcosis patients and healthy controls. The correlation between Tfh cell expression and serum IL-21 level was examined in the patients with hepatic echinococcosis. Results Flow cytometry detected a higher percentage of CD4+CXCR5+ T cells (18.49% ± 5.67% vs. 16.18% ± 4.04%, P < 0.05), CD4+CXCR5+PD-1+ T cells (4.94% ± 1.91% vs. 2.29% ± 0.79%, P < 0.05) and CD4+CXCR5+ICOS+PD-1+ T cells (30.93% ± 24.10% vs. 21.07% ± 14.25%, P < 0.05) in hepatic echinococcosis patients than in healthy controls, and no significant difference was seen in the percentage of CD4+CRCR5+ICOS+ T cells between the patients and controls (0.29% ± 0.32% vs. 0.25% ± 0.31%, P > 0.05) . The serum IL-21 level was significantly higher in the patients with hepatic echinococcosis than in healthy controls ([ 293.35 ± 2 03.65) pg/mL vs. (192.72 ± 70.09) pg/mL, P < 0.05]; however, there was no correlation between the Tfh cell expression and serum IL-21 level in patients with hepatic echinococcosis (P > 0.05). Conclusion The expression of peripheral blood Tfh cells and serum IL-21 is elevated in patients with hepatic echinococcosis, and Tfh cells and IL-21 may contribute to the progression of hepatic echinococcosis.

Effects of immunogenic HER2 on the differentiation of T-cell in mouse / 中国药科大学学报

In order to investigate the effects of p-nitrophenylalanine on the differentiation of T lymphocyte,human epidermal growth factor receptor 2(HER2)mutants were constructed by incorporating p-nitrophenylalanine to the extracellular domain of HER2.Mice were immunized with HER2 mutant to analyze the effects of p-nitrophenylala-nine on the differentiation of T cell subsets.The results showed that the immunogenicity of HER2 protein was significantly enhanced by incorporation of immunogenic amino acids.HER2 mutants induced production of more anti-WT-HER2 antibody and greater titer of antibody than PBS and wild-type HER2 in the fifth week.The differ-entiation frequency of Th1 and Th2 cells showed no significant difference,but the differentiation frequency of Tfh cell was found to increase from 4％ to 8％,while the differentiation frequency of Treg cell was found to decrease from 5％ to 1％ through flowcytometry analysis.The gene expression of Bcl-6 and FOXP3 were determined by quantitative real-time PCR.The results showed that the expression of Bcl-6 mRNA increased about 2 fold,while the expression of FOXP3 mRNA could be decreased to about 50％ in HER2 mutant-immunized group.The secre-tion level of IL-21 in serum was also detected to increase from 4 to 28 pg/mL in HER2 mutant-immunized group.The above results confirm that HER2 mutants containing p-nitrophenylalanine can cause an efficient immune response by activating Tfh cell differentiation.

Changes in follicular helper T ( Tfh) cells and Tfh-related molecules during HIV-1 infection / 中华微生物学和免疫学杂志

Objective To analyze the changes in follicular helper T (Tfh) cells during HIV-1 in-fection, to investigate the influences of Tfh cells and Tfh-related molecules on HIV-1 progression and to pro-vide references for further research on using Tfh cells in highly active antiretroviral therapy ( HAART) and vaccines. Methods This study enrolled 33 patients with HIV-1 infection, including 11 long-term nonpro-gressors (LTNP), 10 rapid progressors (RP) and 12 typical progressors (TP), and 11 healthy subjects (normal controls, NC). Peripheral blood mononuclear cells were isolated from each subject. Multicolor flow cytometry was performed to detect CD4+CD45RA-CXCR5+Tfh and CD4+CD45RA-CXCR3-CXCR5+PD-1+Tfh subsets and the levels of inducible costimulatory molecule (ICOS), IFN-γ and IL-21. Moreover, the levels of IL-10 and the percentages of CD19+B cells in plasma samples of each group were also analyzed. Relationships among Tfh, CD4 and B cells were analyzed. Results The percentages of both Tfh subsets were higher in patients with HIV-1 infection than in NC. Compared with NC, LTNP had the highest percent-age of CD4+CD45RA-CXCR3-CXCR5+PD-1+Tfh cells (P<0. 05). Expression of Tfh-related molecules ICOS, IFN-γ and IL-21 were enhanced significantly upon Staphylococcus enterotoxin B ( SEB) stimulation, ICOS+Tfh cells were negatively related with HIV-1 progression, but had a positive correlation with CD19+B cells (r=-0. 49, P<0. 01; r=0. 60, P<0. 05). IL-10 level in plasma increased significantly in patients withHIV-1 infection , especially in TP and RP ( TP vs NC : P＜0. 01 ; RP vs NC : P<0. 05 ) . Conclusion HIV-1 patients and NC had significant differences in the expression of Tfh cells and Tfh-related molecules in peripheral blood. ICOS+Tfh cells were closely related to the progression of HIV-1 infection and the function of B cells.

Follicular helper T cells in systemic lupus erythematosus: a review / 中华微生物学和免疫学杂志

Systemic lupus erythematosus (SLE) is a severe systemic autoimmune disease, which is characterized by excessive production of autoantibodies caused by B cell hyperactivity. Thus,reducing au-toantibody production can control the development of SLE,and understanding the molecular and cellular fac-tors involved in the differentiation of B cells will provide new therapeutic targets. Follicular helper T cells (Tfh) are defined as a new subset of CD4+T cells specialized in providing help to B cells,which is suspec-ted to play a critical role in the pathogenesis of SLE. In the present review,we give an overview of key mole-cules involved in the differentiation,regulation and functions of Tfh,discuss the roles of Tfh in SLE and de-scribe some potential therapeutic targets for SLE.

Follicular helper T (Tfh) cells involves in the pathogenesis of Henoch-Sch?nlein purpura through affecting CD40/CD40L axis / 中华微生物学和免疫学杂志

Objective To investigate whether follicular helper T(Tfh) cells were involved in the development of Henoch-Sch?nlein purpura(HSP) and Henoch-Sch?nlein purpura nephritis(HSPN) in chil-dren through affecting CD40/CD40L axis. Methods Fifty-five subjects were enrolled in this study and di-vided into four groups as follows:22 children with HSP but without renal involvement(Group A),11 chil-dren with HSPN presenting with microhematuria(Group B),11 children with HSPN presenting with micro-hematuria and proteinuria (Group C) and 11 healthy children (control group). Flow cytometry was per-formed to detect the percentages of CD19+B cells and their subsets,CD19+B cells and CD19+CD38+B cells secreting different Ig classes,CD19+CD40+B cells and their subsets and Tfh cells expressing CD40 ligand (CD40L). Results Compared with the control group,the percentages of CD19+CD86+B,CD19+CD138+B and CD40L+Tfh cells significantly increased in Group C(P<0.05) and slightly increased in Groups A and B (P>0.05). No significant difference in the percentages of CD19+B cells, CD19+CD27+B cells, CD19+B cells or CD19+CD38+B cells expressing IgG, IgM, IgD, CD19+B cells or CD19+B cell subsets secreting CD40 was found between the control group and Groups A,B and C(P>0.05). Moreover,the percentages of CD19+B and CD19+CD38+B cells secreting IgA and IgE in Groups A,B and C were higher than those in the control group(P<0.05). Secretion of IgA by CD19+B and CD19+CD38+B cells were positively correla-ted with the expression of CD40L by Tfh cells(P<0.05). Conclusion Tfh cell-mediated abnormal expres-sion of CD40/CD40L might play an important role in the development of HSP and be related to the clinical severity of renal involvement in HSPN.

The clinical significance of circulating follicular helper T cells in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis / 中华内科杂志

Objective To investigate the change of circulating follicular helper T cells (cTfh) in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis (MPO-AAV), and to analyze the relationship between cTfh and disease activity. Methods Thirty-eight untreated MPO-AAV patients (patient group) and thirty-eight healthy volunteers (control group) were enrolled in this study. cTfh and membrane expression of inducible co-stimulator(ICOS)and programmed cell death protein 1(PD-1) were detected by flow cytometry (FCM). Serum anti-neutrophil cytoplasmic myeloperoxidase antibody (MPO-ANCA) was measured by ELISA. Disease activity was evaluated by Birmingham vasculitis activity score (BVAS). Results Compared with those in control group, the proportions of cTfh, ICOS+Tfh and PD-1+Tfh cells in patient group were significantly higher [(25.9±3.8)％vs. (21.0±5.3)％, P<0.001;(1.8±0.8)％vs. (0.8±0.5)％, P<0.001 and (10.2±2.8)％vs. (8.2±2.2)％, P=0.001, respectively]. Meanwhile, the expression of ICOS and PD-1 on cTfh in patient group was markedly more intensive (59.6±10.0 vs.49.2±6.9, P<0.001 and 532.6±104.2 vs. 485.1±73.4, P=0.025, respectively). In patient group, the proportion of cTfh was positively correlated with the ratio of ICOS+Tfh, the expression of ICOS, the level of MPO-ANCA and BVAS (r=0.407, P=0.011; r=0.705, P<0.001; r=0.737, P<0.001 and r=0.663, P<0.001, respectively). The expression intensity of ICOS on cTfh was positively associated with ICOS+Tfh ratio, serum MPO-ANCA and BVAS (r=0.388, P=0.016; r=0.645, P<0.001 and r=0.653, P<0.001, respectively). Nevertheless, the expression of PD-1 on cTfh was only positively correlated with the ratio of PD-1+Tfh (r=0.473, P=0.003). Conclusions Enhanced cTfh in patients with MPO-AAV might produce MPO-ANCA, which is related to the aggravation of MPO-AAV. Thus, cTfh and its ICOS could be potentially targeted for the treatment of MPO-AAV.

MicroRNA-mediated Regulation of the Development and Functions of Follicular Helper T cells

The germinal center reaction is a key event of humoral immunity, providing long-lived immunological memory. Follicular helper T (T(FH)) cells are a specialized subset of CD4⁺ T cells located in the follicles, which help B cells and thus control the germinal center reaction. T(FH) cell development is achieved by multi-step processes of interactions with dendritic cells and B cells along with the coordination of various transcription factors. Since the T helper cell fate decision program is determined by subtle changes in regulatory molecules, fine tuning of these dynamic interactions is crucial for the generation functional T(FH) cells. MicroRNAs (miRNAs) have emerged as important post-transcriptional regulatory molecules for gene expression, which consequently modulate diverse biological functions. In the last decade, the miRNA-mediated regulation network for the germinal center reaction has been extensively explored in T cells and B cells, resulting in the identification of several key miRNA species and their target genes. Here, we review the current knowledge of the miRNA-mediated control of the germinal center reaction, focusing on the aspect of T cell regulation in particular. In addition, we highlight the most important issues related to defining the functional target genes of the relevant miRNAs. We believe that the studies that uncover the miRNA-mediated regulatory axis of T(FH) cell generation and functions by defining their functional target genes might provide additional opportunities to understand germinal center reactions.

Effect and mechanism of mesenchymal stem cell derived from different sources on inhibiting follicular helper T cells / 器官移植

Objective To investigate the inhibitory effect and underlying mechanism of mesenchymal stem cell (MSC) derived from different sources on follicular helper T cell (Tfh cell). Methods Umbilical cord-derived MSC (UC MSC), bone marrow-derived MSC (BM MSC) and fat-derived MSC (Fat MSC) were co-cultured with peripheral blood mononuclear cell (PBMC) for 48 h. A control group was established. Flow cytometry was adopted to calculate the proportion of Tfh cells among the lymphocytes in four groups. The content of interleukin (IL)-21 in the supernatant was detected by enzyme-linked immune absorbent assay (ELISA) in four groups. BM MSC was co-cultured with PBMC, and supplemented with indoleamine 2,3-dioxygenase (IDO) inhibitor 1-methyl tryptophan (1-MT), IL-10 antibody, human leukocyte antigen (HLA)-G antibody in the 1-MT group, IL-10 inhibition group, HLA-G inhibition group and BM MSC group without addition of other substances. After 48 h culture, flow cytometry was used to detect the percentage of Tfh cells among lymphocytes. Results Flow cytometry demonstrated that compared with the control group, the proportion of Tfh cells in the BM MSC group was significantly decreased (P<0.05). Compared with the BM MSC group, the percentage of Tfh cells in the UC MSC and Fat MSC groups was significantly higher (both P<0.05). ELISA revealed that compared with the control group, the IL-21 content in the BM MSC group was significantly decreased (P<0.05). Compared with the BM MSC group, the IL-21 contents were considerably higher in the UC MSC and Fat MSC groups (both P<0.05). The analysis of underlying mechanism revealed that the proportions of Tfh cells in the 1-MT, IL-10 inhibition and the HLA-G inhibition groups were (1.75±0.07)%, (1.31±0.09)% and (1.50±0.03)%, respectively, which were significantly higher than (1.03±0.43)% in the BM MSC group (all P<0.05). Conclusions BM MSC exerts the highest inhibitory effect upon the differentiation of Tfh cell and IL-21. The mechanism underlying suppressing the differentiation of Tfh cells differentiation is probably correlated to promoting the secretion of IDO.

Proportion of CCR7loPD-1hi follicular helper T cell in peripheral blood of systemic lupus erythematosus patients and its clinical role / 第二军医大学学报

Objective To explore the proportion of CCR7loPD-1hi follicular helper T cell (Tfh) in peripheral blood of the patients with systemic lupus erythematosus (SLE) and its clinical role. Methods Peripheral blood samples were collected from 31 SLE patients, 29 rheumatoid arthritis (RA) patients, 12 Sjögren’s syndrome (SS) patients and 37 healthy controls. Flow cytometry was used to detect the expression levels of C-X-C chemokine receptor 3 (CXCR3), inducible costimulator (ICOS) and signaling lymphocytic activation molecule family member 5 (SLAMF5) on surface of Tfh, and the frequencies of CCR7loPD-1hi Tfh and CCR7hiPD-1lo Tfh in peripheral blood. The correlation between the proportion of CCR7loPD-1hi Tfh in peripheral blood of SLE patients and clinical indicators and the proportion of plasmablasts was analyzed. Results The expression levels of CXCR3, ICOS and SLAMF5 were significantly higher on the surface of the CCR7loPD-1hi Tfh compared with those of the CCR7hiPD-1lo Tfh (t=3.73, 5.06 and 8.27; all P0.05). The proportion of CCR7loPD-1hi Tfh in peripheral blood of the SLE patients was positively correlated with systemic lupus erythematosus disease activity index (SLEDAI), serum anti-double-stranded DNA (dsDNA) titers and the proportion of plasmablasts (r=0.447 1, 0.517 4 and 0.466 9; all P<0.05). Conclusion Increased proportion of CCR7loPD-1hi Tfh in peripheral blood of the SLE patients is associated with increased SLEDAI and increased proportion of plasmablasts; and detecting the Tfh subsets can indirectly reflect the functional status of germinal center and B lymphocytes, which is of great significance for diagnosis, monitoring and prognosis of SLE.

Changes in circulating follicular helper T cells and regulatory follicular T cells in patients with neuromyelitis optica spectrum disorder / 实用医学杂志

Objective To study the changes and significance of the frequencies of circulating follicular helper T cells (cTfh) and circulating regulatory follicular T cells (cTfr) as well as the cTfh/cTfr ratio in neuromyelitis optica spectrum disorder (NMOSD).Methods The frequencies of cTfh,cTfr and B cells in patients with NMOSD and health controls(HCs) were measured by flow cytometry.Enzyme-linked immunosorbent assay was used to detect the level of IL-21 and AQP4-Ab in patients and HCs.Results The frequencies of cTfh and B cells,the cTfh/cTfr ratio and the plasma level of IL-21 werc significantly higher in the relapsing patients than those in the remitting patients and HCs(P ＜ 0.05),and the cTfr level in the relapsing patients was lower than that in the remitting patients and healthy population (P ＜ 0.05).But no statistical differences were observed in the above indexes between the remitting paticnts and HCs.There was also no significant difference in AQP4-Ab level between the patients with relapse and remission (P ＞ 0.05).The frequency of cTfh in the patients wasc positively correlated with the level of B cells and IL-21(P ＜ 0.05),and the frequency of cTfr was negatively correlated with B cells and IL-21 (P ＜ 0.05).The ratio of cTfh/cTfr was positively correlated with B cell frequency and IL-21 level (P ＜ 0.05).AQP4-Ab level had no correlation with the frequencies of cTfh cells and B cells,cTfh/cTfr ratio and IL-21 concentration (P ＞ 0.05).Conclusion The changes in the frequencies of cTfh and cTfr as well as the imbalanced cTfh/cTfr ratio may promote the activation of humoral immunein NMOSD and participate in the pathogenesis of this disease.

Optimization of in vitro human follicular helper T cell differentiation condition / 中国药科大学学报

In order to explore the regulation mechanisms of follicular helper T cell (Tfh Cell) differentiation,optimized conditions of in vitro induction from both peripheral blood mononuclear cells and MAC sorted Na(i)ve CD4 + T cells to human Tfh cells were developed.Induction efficiency difference of TCR signal anti-hCD3e stimulation between coated on solid phase and in soluble phase was also determined.Differentiation efficiency of CD4 + CXCR5 + ICOS+PD-1 + Tfh cell was determined by FACS while the expression level of IL-21 in cell supernatant was determined by ELISA tests.An ultimate induction condition that 5 μg/mL coated overnight anti-hCD3e stimulated na(i)ve CD4 + T cells to differentiate into Tfh at an up to 20.4％ percentage was finally determined.The optimization of in vitro induction protocol of human Tfh provided an effective examine platform for the studies on Tfh differentiation mechanisms and related pharmacology,toxicity and metabolic experiments.