Bacterial dissemination in Mycobacterium tuberculosis by CD+ T-cells & proinflammatory cytokines

Background & objectives: As CD4+ and CD8+ T lymphocyte numbers decline, the conventional, localized forms of tuberculosis shift to the atypical, disseminated forms. Variations in lymphocyte and immune cell expression levels affect how tuberculosis manifests in disseminated forms. Understanding the relationship between lymphocyte counts (CD4+ and CD8+) and pro-inflammatory cytokines such as tumour necrosis factor-alpha, interleukin-12 and interferon, we may therefore be able to shed light on how infections spread and suggest potential biomarkers for these immune factors. Methods: In this study, 15 guinea pigs were infected with Mycobacterium tuberculosis (M.tb) H37Rv strain and grouped into three groups of five each for further investigation. Serum samples and bronchoalveolar lavage (BAL) fluid were examined for the expression of pro-inflammatory cytokines and T-cell subsets in guinea pigs infected with pulmonary tuberculosis and disseminated tuberculosis. Results: We found that M.tb escapes macrophages due to pro-inflammatory cytokine dysregulation. Despite the protective immunity created by T-cells and cytokines, M.tb bacilli may spread to other organs due to inflammation induced by these immune components. A high number of T-cells and stimulated cytokine production are involved in triggering inflammation after necrotic tissue develops and tuberculosis spreads. Interpretation & conclusions: Our findings imply that increased bacilli in the spleen at the 8th wk of infection may be caused by the overexpression of CD4+ T-cell lymphocyte subsets and cytokines that generated inflammation during the 4th wk of infection. This is a pilot study with a small sample size and less assertive inference. Larger studies would be helpful to validate the results of the present investigation.

Effect of propolis on Th2 and Th17 cells: interplay with EtxB- and LPS-treated dendritic cells

Dendritic cells (DCs) are antigen-presenting cells that drive the differentiation of T CD4+ cells into different profiles according to the nature of the antigen or immunomodulator. Propolis is a resinous product made by bees that has numerous pharmacological properties, including an immunomodulatory action. To assess whether propolis can modulate the activation of CD4+ T cells by stimulating DCs with heat-labile enterotoxin B subunit (EtxB) or lipopolysaccharide (LPS), we aimed to elucidate the mechanisms affected by propolis in the differential activation of T lymphocytes. Cell viability, lymphocyte proliferation, gene expression (GATA-3 and RORc), and cytokine production (interleukin (IL)-4 and IL-17A) were analyzed. Propolis, EtxB, and LPS induced a higher lymphoproliferation compared with the control. Propolis induced GATA-3 expression and, in combination with EtxB, maintained the baseline levels. Propolis alone or in combination with LPS inhibited RORc expression. EtxB alone and in combination with propolis increased IL-4 production. Propolis in combination with LPS prevented LPS-induced IL-17A production. These results opened perspectives for the study of biological events that may be favored by propolis by promoting Th2 activation or helping in the treatment of inflammatory conditions mediated by Th17 cells.

The effect of PD-1/PD-L1 signaling axis on the interaction between CD19+B cells and CD4+T cells in peripheral blood of patients with systemic lupus erythematosus

Abstract Background The defect of B cell self-tolerance and the continuous antigen presentation by T cells (TCs) mediated by autoreactive B cells (BCs) play a key role in the occurrence and development of systemic lupus erythematosus (SLE). PD-1/PD-L1 signaling axis negatively regulates the immune response of TCs after activation and maintains immune tolerance. However, the effect of PD-1/PD-L1 signaling axis on the interaction between CD19+B/CD4+TCs in the peripheral blood of patients with SLE has not been studied in detail. Methods PD-1/PD-L1 and Ki-67 levels in peripheral blood (PB) of 50 SLE patients and 41 healthy controls (HCs) were detected through flow cytometry, and then the expression of PD-1+/−cells and PD-L1+/−cells Ki-67 was further analyzed. CD19+B/CD4+TCs were separated for cell culture and the supernatant was collected to determine proliferation and differentiation of TCs. IL-10 and IFN-γ secretion in the supernatant was also determined using ELISA. Results The PD-1, PD-L1, and Ki-67 levels on CD19+B/CD4+TCs in patients with SLE were higher than HCs. In CD19+B/CD4+TCs of SLE patients, the proliferative activity of PD-L1+ cells was higher than that of PD-L1− cells, and the proliferative activity of PD-1+ cells was higher than that of PD-1− cells. In the system co-culturing CD19+B/CD4+TCs from HCs/SLE patients, activated BCs promoted TCs proliferation and PD-L1 expression among TCs. Addition of anti-PD-L1 to co-culture system restored the proliferation of TCs, and inhibited IL-10/IFN-γ level. The addition of anti-PD-L1 to co-culture system also restored Tfh and downregulated Treg in HCs. Conclusions Axis of PD-1/PD-L1 on CD19+B/CD4+TCs in PB of SLE patients is abnormal, and cell proliferation is abnormal. In CD19+B/CD4+TCs of SLE patients, the proliferative activity of PD-L1+ and PD-1+ cells compared with PD-L1− and PD-1− cells in SLE patients, respectively. CD19+B/CD4+TCs in SLE patients can interact through PD-1/PD-L1.

Enhancing the sensitivity of HIV DNA detection: a magnetic bead-based method / 中国输血杂志

【Objective】 To establish a magnetic bead enrichment strategy for the detection of human immunodeficiency virus deoxyribonucleic acid (HIV DNA) in peripheral blood, and to verify the improvement of the sensitivity of this method for the detection of HIV DNA in HIV infected patients after early antiretrovital treatment (ART). 【Methods】 Peripheral whole blood was collected at 4 timepoints in one ART HIV window period (WP) patient. Peripheral blood mononuclear cells (PBMCs) were isolated on a Ficoll gradient. CD4+ T lymphocytes were enriched from total PBMCs by negative sorting. HIV DNA concentration in magnetic beads enriched group and whole blood group was detected by HIV DNA detection kit. 【Results】 CD4+ T cells were isolated by magnetic beads and identified by FCM for purity at (96.4 ± 2.6)%. The viability was (95.9 ± 2.9)%, as demonstrated by trypan blue staining. The person on continued ART treatment in this study had significantly greater reduction in HIV viral load and undetectable HIV plasma RNA at follow up timepoint 4. No HIV DNA was detected in the whole blood group at all 4 timepoints. The quantitative results of HIV DNA in the CD4+ T lymphocyte group of the magnetic bead enrichment group were 73.4, 429.3, 137.1, 449.9 copies/106 CD4+ T cell′s respectively. 【Conclusion】 The magnetic bead enrichment method can be more sensitive in detecting the limit low copy HIV DNA in blood samples, and provide early confirmatory data for HIV WP infection and breakthrough infection after ART treatment.

Analysis of CD4+ T cell count of different genotypes of HIV infected people in Xi'an in 2017 -2021 / 公共卫生与预防医学

Objective To study the difference of CD4+ T cell count among different genotypes of HIV infected people in Xi'an from 2017 to 2021. Methods A total of 1 623 newly diagnosed AIDS patients in the AIDS prevention and control information system in Xi'an from 2017 to 2021 were selected. The genotypes of all the patients were sequenced, and the differences of CD4+T cell counts among different genotypes were analyzed. Results From 2017 to 2021, the main genotype of HIV infected people in Xi'an was CRF01_ AE（921/1623）、CRF07_ BC（145/1623）、CRF08_ BC (557/1623), the gene cluster is mainly CRF01_ AE (cluster 1) (185/ 1623) and CRF01_ AE (cluster 2) (1438/1623), where CRF01_ The average CD4+ T cell count of AE genotype was (146.26 ± 11.63)/μ L，CRF07_ The average CD4+ T cell count of BC genotype was (254.69 ± 15.49)/μ L，CRF08_ The average CD4+ T cell count of BC genotype was (217.96 ± 12.89)/μ L，CRF01_ The average number of CD4+ T cells in AE (cluster 1) was (185.58±12.79)/ μ L，CRF01_ The average number of CD4+ T cells in AE (cluster 2) was (179.90 ± 15.96)/ μ 50. There was significant difference in CD4+ T cell count among patients with different gene subtypes and gene clusters (P<0.05). Conclusion From 2017 to 2021, the main genotype of HIV infected people in Xi'an was CRF01_ AE, the gene cluster is mainly CRF01_ AE (Cluster 2), there were significant differences in CD4+T cell counts among patients with different gene subtypes and gene subsets, which could serve as a reference target for AIDS treatment in this Municipality.

Human follicular helper T lymphocytes critical players in antibody responses / Linfócitos T auxiliares foliculares humanos: células essenciais para a resposta de anticorpos

ABSTRACT Follicular helper T lymphocytes are a subpopulation of CD4+ T lymphocytes initially identified in germinal centers of follicles found in secondary lymphoid organs. The primary function of follicular helper T lymphocytes is to help B lymphocytes' antibody production. Changing of antibody class and affinity, B cell differentiation and memory generation depend on cooperation between follicular helper T lymphocytes and B cells. In blood, follicular helper T lymphocytes are called circulating follicular helper T lymphocytes. They are considered to have specificities similar to those developed in the secondary lymphoid organs. The phenotype of human follicular helper T lymphocytes is given by simultaneous expression of the markers CXCR5, Bcl-6, CD40L, PD-1, and ICOS. In germinal centers, follicular helper T lymphocytes synthesize interleukin 21 as predominant cytokine. In blood, subpopulations of circulating follicular helper T lymphocytes can be recognized, with different expressions of the classical follicular helper T lymphocytes markers and, in addition, can express other markers such as CXCR3 and CCR6. Presently, there is great interest in follicular helper T lymphocytes and circulating follicular helper T lymphocytes in vaccination studies as indicators of immunization efficacy. In addition, follicular helper T lymphocytes are investigated as possible markers of activity in many diseases and potential therapeutic intervention. This short review describes aspects of immunobiology and quantification of follicular helper T lymphocytes and circulating follicular helper T lymphocytes, and presents a few examples of related findings in systemic lupus erythematosus, rheumatoid arthritis, HIV infection and vaccination.

RESUMO Linfócitos T auxiliares foliculares são uma subpopulação de linfócitos T CD4+ identificada inicialmente nos centros germinativos dos folículos dos órgãos linfoides secundários. Sua função primordial é auxiliar os linfócitos B na produção de anticorpos. A mudança de classe e de afinidade dos anticorpos, a diferenciação das células B e a geração de memória dependem da cooperação entre os linfócitos T auxiliares foliculares e as células B. No sangue, recebem o nome de linfócitos T auxiliares circulantes. Considera-se que possuem especificidades semelhantes às desenvolvidas nos órgãos linfoides secundários. O fenótipo dos linfócitos T auxiliares humanos é dado pela expressão conjunta dos marcadores CXCR5, Bcl-6, CD40L, PD-1 e ICOS. Nos folículos, linfócitos T auxiliares sintetizam a interleucina 21 como citocina predominante. No sangue, são descritas várias subpopulações de linfócitos T auxiliares circulantes com expressões variadas dos marcadores clássicos de linfócitos T auxiliares, além de poderem agregar outros, como CXCR3 e CCR6. Existe um enorme interesse no estudo de linfócitos T auxiliares e linfócitos T auxiliares circulantes, para a avaliação de eficácia de vacinação. São também investigados como possíveis marcadores de atividade em muitas doenças e potenciais intervenções terapêuticas. Esta breve revisão descreve aspectos da imunobiologia e da quantificação de linfócitos T auxiliares humanos e linfócitos T auxiliares circulantes, além de apresentar alguns achados relacionados em lúpus eritematoso sistêmico, artrite reumatoide, infecção por HIV e vacinação.

Research progress on the relationship between IL-37 and periodontitis / 口腔疾病防治

@#Periodontitis is the inflammation of periodontal tissue caused by dental plaque, which absorbs the alveolar bone and cementum. The immune response triggered by CD4+T cells is the key factor for the aggravation of periodontitis. The activation of dendritic cells and the receptor activator of the NF-κB ligand (RANKL) pathway is an important link in the alveolar bone resorption of periodontal tissue. Pro-inflammatory factors such as interferon-γ (IFN-γ), tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) also play important roles in the development of periodontitis. Interleukin-37(IL-37), which is a newly discovered cytokine in the IL-1 family, has five shear variants from a to e, among which the clover β-structure encoded by exon 4 plays an important role in the binding of cytokines and the corresponding receptors. IL-37 has strong anti-inflammatory and inhibition of autoimmunity, can enter the nucleus with the help of caspase-1 and bind with Smad proteins to regulate the transcription of pro-inflammatory genes. Extracellular IL-37 can bind to IL-18 binding protein and inhibit the production of pro-inflammatory factors. IL-37 can inhibit the progression of periodontitis by inhibiting the RANKL signaling pathway, inhibiting the proliferation and differentiation of dendritic cells and CD4+T cells, binding to Smad proteins, and releasing pro-inflammatory factors such as IFN-γ and TNF-α. The IL-37 concentration in periodontal tissue can indicate the progression of periodontitis. Few studies have described the interaction between the anti-inflammatory factor IL-37 and periodontitis. Thus, in this paper, the structure and function of IL-37 and the related factors between IL-37 and periodontitis will be reviewed.

Clinical laboratory features of Meigs' syndrome: a retrospective study from 2009 to 2018 / 医学前沿

Meigs' syndrome (MS), a rare complication of benign ovarian tumors, is easily misdiagnosed as ovarian cancer (OC). We retrospectively reviewed the clinical laboratory data of patients diagnosed with MS from 2009 to 2018. Serum carbohydrate antigen 125 and HE4 levels were higher in the MS group than in the ovarian thecoma-fibroma (OTF) and healthy control groups (all P < 0.05). However, the serum HE4 levels were lower in the MS group than in the OC group (P < 0.001). A routine blood test showed that the absolute counts and percentages of lymphocytes were significantly lower in the MS group than in the OTF and control groups (all P < 0.05). However, these variables were higher in the MS group than in the OC group (both P < 0.05). The neutrophil-to-lymphocyte ratio (NLR) was also significantly lower, whereas the lymphocyte-to-monocyte ratio was higher in the MS group than in the OC group (both P < 0.05). The NLR, platelet-to-lymphocyte ratio, and systemic immune index were significantly higher in the MS group than in the OTF and control groups (all P < 0.05). The hypoxia-inducible factor-1 mRNA levels were also significantly higher, whereas the glucose transporter 1, lactate dehydrogenase, and enolase 1 mRNA levels were lower in peripheral CD4

Advances in miRNA regulation of Th17/Treg balance / 医学研究生学报

T helper 17 (Th17) and regulatory T cells (Tregs) are two distinct subsets of T cells that play a key role in the development of autoimmunity and inflammation. Th17 cells are thought to be the key effector T cells that induce inflammatory responses while Tregs inhibit the development of inflammation by regulating effector T cell activity to maintain peripheral immune tolerance. Th17/Treg imbalance can lead to the development of autoimmune diseases. MicroRNAs (miRNAs) are small endogenous non-coding RNA molecules in eukaryotes that play important regulatory roles in the maintenance of homeostasis in the immune system and the development of autoimmune diseases. Abnormal expression of miRNA will result in a broken or dysfunctional balance of differentiation between Th cell subsets, leading to inflammation or autoimmune diseases. This article provides an overview of the research advances in miRNA regulation of Th17/Treg balance to explore the role and clinical significance of miRNAs in Th17/Treg balance and maintenance of immune system balance.

Advances in miRNA regulation of Th17/Treg balance / 医学研究生学报

T helper 17 (Th17) and regulatory T cells (Tregs) are two distinct subsets of T cells that play a key role in the development of autoimmunity and inflammation. Th17 cells are thought to be the key effector T cells that induce inflammatory responses while Tregs inhibit the development of inflammation by regulating effector T cell activity to maintain peripheral immune tolerance. Th17/Treg imbalance can lead to the development of autoimmune diseases. MicroRNAs (miRNAs) are small endogenous non-coding RNA molecules in eukaryotes that play important regulatory roles in the maintenance of homeostasis in the immune system and the development of autoimmune diseases. Abnormal expression of miRNA will result in a broken or dysfunctional balance of differentiation between Th cell subsets, leading to inflammation or autoimmune diseases. This article provides an overview of the research advances in miRNA regulation of Th17/Treg balance to explore the role and clinical significance of miRNAs in Th17/Treg balance and maintenance of immune system balance.

Blockade of IL-27 signaling ameliorates herpes stromal keratitis with upregulated CD4+ Foxp3+ regulatory T cells influx in mice

Purpose: The purpose of this study was to investigate the production of IL-27 p28 and EBI3 in the ocular inflammatory sites, and the role of IL-27 signaling in a model of HSV-1 induced herpetic stromal keratitis (HSK). Methods: The BALB/c mice were injected intraperitoneally (24 h before infection) with anti-IL-27 antibody or IgG antibody as control, infected with HSV-1 via corneal scarification, and then injected intraperitoneally with anti-IL-27 antibody or IgG antibody at 1, 3, and 5 days postinfection. Slit lamp and histopathology were used to assess disease outcome. The levels of IL-27 p28 and EBI3 in corneas were determined by western blotting and immunofluorescence. Furthermore, viral titers were determined, and immune cell infiltrates were collected and analyzed by flow cytometry. Results: We found that the levels of IL-27 p28 and EBI3 in corneas were elevated significantly at the peak of HSK, and both of them were expressed simultaneously in the epithelium, stroma, and endothelium of corneas. In the group of anti-IL-27 treatment, the severity of the corneal lesion and CD4+ T cells infiltration were significantly decreased, and the percentage of CD4+ Foxp3+ Tregs was upregulated markedly in the spleen, DLNs and cornea of HSK mice compared to IgG treatment. Conclusion: These results provided evidence that IL-27 as a pathogenic pro-inflammatory cytokine controlled CD4+ Foxp3+ Tregs production in HSK, which ultimately resulted in promoting the progression of HSK and poor prognosis.

Artesunate promotes Th1 differentiation from CD4+ T cells to enhance cell apoptosis in ovarian cancer via miR-142

The aim of this study was to evaluate the influence of artesunate on Th1 differentiation and its anti-tumor effect on ovarian cancer. A Murine ovarian cancer model was established by ID8 cells transplantation. The expression of miR-142 and Sirt1 proteins in peripheral CD4+ T cells were quantified with qRT-PCR and western blot, respectively. Peripheral CD4+ T cells were induced for Th1 differentiation. The percentages of apoptosis of Th1/CD4+ T cells and ovarian cancer cells were analyzed by flow cytometry. The IFN-γ level was examined through enzyme-linked immunosorbent assay. Artesunate promoted miR-142 expression in peripheral CD4+ T cells and Th1 differentiation from CD4+ T cells. Artesunate promoted cell apoptosis of ovarian cancer cells by inducing Th1 differentiation. By up-regulating miR-142, artesunate suppressed Sirt1 level and promoted Th1 differentiation. Artesunate enhanced the pro-apoptotic effects of Th1 cells on ovarian cancer via the miR-142/Sirt1 pathway. Artesunate promoted Th1 differentiation from CD4+ T cells by down-regulating Sirt1 through miR-142, thereby enhancing cell apoptosis in ovarian cancer.

Effect and Mechanism of Active Fraction of Polyrhachis vicina in Treatment of Systemic Lupus Erythematosus(SLE) / 中国实验方剂学杂志

Objective: To observe the effect of an active fraction of Polyrhachis vicina (AFPV) on systemic lupus erythematosus (SLE) and its possible mechanism based on animal and cell models. Method: Totally 60 SD rats were randomly divided into normal control group, model group, prednisone acetate group (5 mg·kg-1), and high, medium and low-dose AFPV groups (400, 200, 100 mg·kg-1). SLE model was replicated with bovine serum albumin-Freund's complete (incomplete) adjuvant. Arthus reaction was observed to study the effect of AFPV on the diameter of back skin redness in rats with SLE. The expressions of anti-double-stranded DNA (dsDNA) antibody, complements 3 (C3), complement 4 (C4), immunoglobulin M (IgM), interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-31 (IL-31) and interleukin-33 (IL-33) in serum were detected by enzyme-linked immunosorbent assay. CD4+T cells were isolated from the spleens of MRL/lpr and C57BL/6J mice at the age of 16 to 18 weeks by immunomagnetic beads method. The expressions of miR-200a and miR-155 and the levels of zinc-finger-enhancer binding protein 1(ZEB1) and suppressor of cytokine signaling1(SOCS1) in CD4+T cells were observed to explore the effect of AFPV on SLE and its possible mechanism. Result: Compared with the normal group, the diameter of back skin swelling in the model group was significantly increased (PPPPPPP+T cells of MRL/lpr lupus mice. Compared with the model group, the expression of microRNA-200a increased significantly, the expression of microRNA-155 decreased significantly (PPConclusion: AFPV has therapeutic effect on rats with SLE, its mechanism may be related to the regulation of miR-200a/ZEB1 and miR-155/SOCS1.

Expression of PD-1hiCXCR5-CD4+T cells in patients with systemic lupus erythematosus / 中华风湿病学杂志

Objective To investigate the expression of peripheral programmed death (PD)-1hiCXCR5-CD4+T cells and its clinical significance in systemic lupus erythematosus (SLE). Methods Peripheral blood PD-1hiCXCR5-CD4+ T cells from 21 SLE patients and 16 healthy controls were examined by flow cytometry. The levels of serum anti-double-stranded deoxyribonucleic acid (dsDNA) antibodies were determined using immunoradiometric as-say. Data were analyzed with t test and Pearson's correlation test. Results The per-centages of PD-1hiCXCR5- cells within CD4+ T cell were significantly higher in SLE patients [(2.1 ±2.0)％] compared to normal controls [(0.3±0.3)％] (t=2.959, P<0.01). The percentages of PD-1hiCXCR5-cells within CD4+T cells in moderate to severe active SLE patients (3.0 ±2.0)％ was significantly increased compared to patients with mild or inactive (1.0±1.4)％(t=2.574, P<0.05) and normal controls (0.3±0.3)％ (t=5.149, P<0.01). The percentages of PD-1hiCXCR5- cells within CD4+ T cells from SLE patients were positively related with systemic lupus erythematosus disease activity index (SLEDAI) (r=0.475, P=0.0297). SLE patients in serum anti-dsDNA antibodies positive group (2.7±2.1)％displayed a higher percentage of PD-1hiCXCR5-cells within CD4+T cells than patients in serum anti-dsDNA antibodies negative group (0.6 ±0.5)％ (t=2.303, P<0.05). The percentages of PD-1hiCXCR5-cells within CD4+T cells from SLE patients were positively correlated with anti-dsDNA antibody titers. Conclusion The percentages of PD-1hiCXCR5- cells within CD4+ T cells from SLE patients are increased and are positively correlated with SLEDAI and anti-dsDNA antibody levels. Increased percentage of PD-1hiCXCR5-cells within CD4+T cells might play an important role in the pathogenesis of SLE.

Mecanismos epigenéticos en la plasticidad y flexibilidad de los linfocitos T CD4 / Epigenetic mechanisms in plasticity and flexibility of the CD4 T cells

Watson y Crick descifraron en 1953 la estructura del ácido desoxirribonucleico (ADN), a partir de ese momento se produjo una revolución en el campo de la Biología Molecular y la Genética, cuyo colofón fue la publicación de la primera versión del genoma humano en el año 2001. Sin embargo, esto solo fue el principio de una nueva revolución de la ciencia moderna: la epigenética. Una forma de regular el patrón de expresión génica sería modificar la estructura de la cromatina a través de diversos mecanismos epigenéticos. Los linfocitos T CD4, no están alejados de estos mecanismos, donde su diferenciación la inducen citocinas producidas por células presentadoras de antígeno (APC) y los propios linfocitos T. El programa de diferenciación sería gobernado por factores de transcripción que promueven la expresión de genes de citocinas en los linfocitos T y cambios epigenéticos en los loci génicos de citocinas, que pueden asociarse al compromiso estable en un subgrupo particular. La flexibilidad o la estabilidad de las células T pudieran ser representadas como una serie de transiciones menos estables para estados más estables, que incluyen los mecanismos de metilación del ADN, modificaciones de las histonas y la presencia de los micro ARN (ácido ribonucleico). Todo esto refuerza o desestabiliza la expresión de los factores para la estabilidad y plasticidad de estas células. El entendimiento de estos factores podría revolucionar el enfoque de la biología evolutiva y del desarrollo; y su aplicación en las ciencias médicas(AU)

Watson and Crick deciphered the physical structure of the deoxyribonucleic acid (DNA) in 1953. From that moment on there was a revolution in the field of Molecular Biology and Genetics, whose culmination was the publication of the first version of the human genome in the year 2001. However, this was only the beginning of a new revolution in modern science: Epigenetics. One way to regulate the pattern of gene expression would be to modify the structure of chromatin through various epigenetic mechanisms. CD4 T lymphocytes (CD4 cells) are not far from these mechanisms, where its differentiation is induced by the cytokines produced by antigen-presenting cells (APC) and the T lymphocytes themselves. The differentiation program would be governed by transcription factors that promote the expression of cytokine genes in T lymphocytes and epigenetic changes in gene loci of cytokines, which may be associated with stable commitment in a particular subgroup..The flexibility or stability of T cells could be represented as a series of less stable transitions for more stable states, including the mechanisms of DNA methylation, histone modifications and the presence of micro RNA (ribonucleic acid). All this reinforces or destabilizes the expression of the factors for the stability and plasticity of these cells. Understanding these factors could revolutionize the approach of evolutionary biology and development, as well as its application in the medical sciences(AU)

Investigation on antigen-specific T cell responses in type 2 diabetes mellitus patients / 中华内分泌代谢杂志

Objective To investigate the antigen-specific T cell functionality in type 2 diabetes mellitus patients. Methods Peripheral blood from 38 type 2 diabetes mellitus patients and 47 health controls (control group) have been collected. The proportions of CD4+and CD8+T cell as well as the ratio of CD4+/CD8+were monitored by flow cytometry. Meanwhile, antigen- nonspecific and specific Th1 responses were compared between two groups through detecting interferon (IFN)-γ, interleukin 2 (IL-2), and tumor necrosis factor (TNF)-α producing cells upon propylene glycol monomethyl ether acetate (PMA)/ionomycine and epstein-barr virus ( EBV) peptides stimulation, respectively followed by an intracellular cytokine staining. Results Compared to control group, the proportion of CD4+T cell and the ratio of CD4+/CD8+were significantly increased in type 2 diabetes mellitus group (P＜0.05) whereas CD8+T cells exhibited no significant difference between two groups. Antigen-nonspecific Th1 responses in type 2 diabetes mellitus patients were significantly decreased, demonstrated by lower percentages of IFN-γ, IL-2, and TNF-α producing CD4+T cells when compared to control group , while CD8+T cells in type 2 diabetes mellitus patients exhibited similar cytokine production patterns. However, when stimulated by EBV specific peptides, the percentages of IFN-γ, IL-2, and TNF-α producing CD8+T cells were significantly higher in type 2 diabetes mellitus patients than those in control group (P＜0.05). HbA1Cwas positively correlated with the percentage of EBV-specific TNF-α producing CD8+T cells (P＜0.05). Conclusion In type 2 diabetes mellitus, the secretion capacity of CD4+and CD8+T cell was significantly decreased and the antigen-specific responses represent the presence of an abnormal activated status, which indicates that chronic hyperglycemia may damage T cells function and aggravate chronic inflammation.

CD226 involved in regulation of CD4+T cell / 中国免疫学杂志

CD226 is a typeⅠtransmembrane glycoprotein expressed on various immune cell membranes,such as NK cells,T cells,monocytes and other cells.After binding to ligand CD112 or CD155, CD226 mediates the differentiation, proliferation and functional regulation of various immune cells to participate many physiological and pathological activities.This paper mainly focuses on two aspects,the first is CD226 on CD4+T cell immune regulation, the seconds is the CD226 involved in the progress of many dis-ease.Detailed explanation of CD226 involved in naive CD4+T cell proliferation and differentiation, Th1/Th2/Th17 cells polarization and regulatory function of Treg cells.

The role of RAGE in high mobility group box-1 protein1-mediated CD4+T cells differentiation to Th1/Th2 / 中华急诊医学杂志

Objective To explore the role of receptor for advanced glycation end products (RAGE) in HMGBl-mediated CD4+ T cells differentiation to Th1/Th2.Methods CD4+ T lymphocytes isolated from the spleens of male BALB/C mice by magnetic beads were suspended in RPMI-1640 with 10％ FCS in 2× 106cell/well on 96-well cell culture plates in vitro.The cells were randomly divided 4 groups according to concentration of HMGB1 treatment:control group,10 ng/mL group,100 ng/mL group,1 000 ng/mL group after stimulation with ConA in 3 μg/mL for 12 hours.IL-4 and IFN-γ levels in culture supernatants were quantitated by ELISA kits after HMGB1 stimulation for 12,24,and 48 h.According to the results,cultured cells were exposed to HMGB1 in 100 ng/mL for 24 h in the following experiments.The cells were randomly divided into 4 groups:control group,A group,B group,C group,and each group were cultured with ConA in 3 μg/mL for 24 h.The cells of control group and other three groups were stimulated with PBS or 100 μg/L HMGB1 for 24 h.The cells of B,C groups were incubated with 1/200 diluted 5 μg/L anti-RAGE Abs (anti-bodies) or PBS for 2 h before HMGB1 stimulation.The cell suspension was obtained to detect the levels of IL-4 and IFN-γ by EILSA and the protein levels and mRNA expressions of RAGE,CATA-3 were detected by western-blot and real-time fluorescent quantitative PCR,respectively.ResuRs Compared with control group,CD4+ T cells incubated with increasing concentrations of HMGB1 (100,1 000 ng/mL) for 24 h resulted in a decrease in IFN-γ/IL-4 ratio (P＜0.05).When CD4+ T cells were exposed to 100 ng/mL HMGB1 for 12 h,IFN-γ/IL-4 ratio was markedly increased.However,CD4+ T cells treated with 100 ng/mL HMGB1 for 24,48 h,IFN-γ/IL-4 ratio was markedly inhibited (P＜0.05).Compared with control group,protein levels and mRNA expressions of RAGE and GATA3 of cells in A group were significantly increased (P＜0.05),and IFN-γ/IL-4 ratio of cell suspension in A group and B group was significantly down-regulated (P＜0.05).Compared with A group,IFN-γ/IL-4 ratio of cell suspension in C group was increased (P＜0.05),and expression of GATA3 mRNA was down-regulated (P＜0.05).Compared with A group,protein level of RAGE of cells in C group was significantly down-regulated (P＜0.05),but protein level of RAGE of cells in C group was still increased compared with control group (P＜0.05).Conclusion Th1/Th2 differentiation induced by HMGB1 on CD4+ T lymphocytes in vitro was at least partly mediated by over-activating RAGE/GATA3 pathway.

Psoralen inhibits RAW264.7 differentiation into osteoclasts and bone resorption by regulating CD4+T cell differentiation / 中国中药杂志

This paper aimed to investigate whether psoralen inhibits the differentiation and bone resorption by regulating CD4+T cell differentiation in RANKL-induced osteoclastogenesis in RAW264.7 cells, and elucidate its mechanism for osteoporosis. CD4+T cells were isolated from spleen cells of Balb/c mice by immunomagnetic separation method. The cells were divided into blank control group and psoralen group. The cells were cultured in 24-well plates and cultured for 3 days, and then they were collected for co-culture experiments after 4 days. Co-culture experiments were divided into RAW264.7 cell group, psoralen+RAW264.7 cell group, without psoralen treatment of CD4+T cells+RAW264.7 cell group, psoralen treatment of CD4+T cells+RAW264.7 cell group. After 5 days of co-culture, TRAP staining was used to detect the number of osteoclasts, and after 8 days of co-culture, bone resorption was evaluated by toluidine blue staining. The expressions of RORγt, Foxp3, IL-17, TNF-α, TGF-β and IL-10 in CD4+T cells and osteoclast differentiation-related genes MMP-9, TRAP and Cat-K were detected by Real-time polymerase chain reaction (RT-PCR); ELISA kit was used to detect IL-17, TNF-α, TGF-β and IL-10 and other cytokines levels. Our data confirmed that the psoralen significantly promoted the expression of Foxp3, TGF-β and IL-10 in CD4+T, and inhibited the expression of RORγt, IL-17 and TNF-α in CD4+T, the CD4+T cells without treatment by psoralen can significantly promote RANKL-induced differentiation of RAW264.7 to osteoclasts, and psoralen treatment of CD4+T can significantly inhibit RANKL-induced RAW264.7 osteoclast differentiation and bone resorption. Taken together, psoralen inhibits the differentiation and bone resorption of RAW264.7 into osteoclasts by promoting the development of CD4+ CD25+ Treg/Th17 balance in CD4+T cells to CD4+CD25+T.

Experimental study on the in vitro induction of regulatory T cells by umbilical cord mesenchymal stem cells with positive human leukocyte antigen-G / 器官移植

Objective To explore the effect of umbilical cord mesenchymal stem cells with positive human leukocyte antigen(HLA)-G on inducing the production of regulatory T cells(Treg) in vitro.Methods Umbilical cord mesenchymal stem cells were isolated from umbilical cord of neonates. PEGFP-N1-HLA-G plasmid was transfected into the human umbilical cord mesenchymal stem cells by liposome transfection, as PEGFP-N1-HLA-G group. PEGFP-N1 empty vector plasmid was transfected into the human umbilical cord mesenchymal stem cells, as PEGFP-N1 group. The human umbilical cord mesenchymal stem cells without empty vector under the same conditions were set as blank control group. Markers of the umbilical cord mesenchymal stem cells were detected using flow cytometry. The expression of HLA-G protein in each group of cells was identified by Western Blot. After mixed-culturing with CD4+T cells in peripheral blood of healthy subjects for 24 h and 48 h, the proportion of CD4+CD25+Foxp3+Treg in total T cells of each group was detected by flow cytometry. Results CD45, CD34 and HLA-DR presented negative expression on umbilical cord mesenchymal stem cells, while CD29, CD44 and CD105 presented positive expression. HLA-G protein could be expressed in the PEGFP-N1-HLA-G group, which had statistically significant difference compared with the blank control group and PEGFP-N1 group (both P<0.01). After PEGFP-N1-HLA-G group and CD4+T cells were mixed-cultured for 24 h and 48 h, CD4+CD25+Foxp3+Treg accounted for (15.3±1.9)% and (14.3±2.1)% of the total T cells respectively, both of which presented statistically significant difference compared with the blank control group and PEGFP-N1 group (all P<0.05). Conclusions Umbilical cord mesenchymal stem cells with HLA-G gene modified can effectively induce the production of CD4+CD25+Foxp3+Treg in vitro.