Gastric cancer cells induce human CD4~+ Foxp3~+ regulatory T cells through the production of TGF-β1

AIM: To elucidate the molecular and cellular features responsible for the increase of regulatory T cells (Tregs) in gastric cancer. METHODS: The frequencies of CD4 + Foxp3 + Tregs and the level of transforming growth factor-β1 (TGF-β1) were analyzed from 56 patients with gastric cancer byflow cytometry and enzyme-linked immunosorbent assay respectively. Foxp3 gene expression was analyzed by real-time polymerase chain reaction. The gastric cancer microenvironment was modeled by establishing the coculture of ...     

Gastric cancer cells induce human CD4^＋ Foxp3^＋ regulatory T cells through the production of TGF-β1

AIM: To elucidate the molecular and cellular features responsible for the increase of regulatory T cells (Tregs) in gastric cancer.METHODS: The frequencies of CD4⁺Foxp3⁺ Tregs and the level of transforming growth factor-β1 (TGF-β1) were analyzed from 56 patients with gastric cancer by flow cytometry and enzyme-linked immunosorbent assay respectively. Foxp3 gene expression was analyzed by real-time polymerase chain reaction. The gastric cancer microenvironment was modeled by establishing the co-culture of gastric cancer cell line, MGC-803, with sorting CD4⁺ T cells. The normal gastric mucosa cell line, GES-1, was used as the control. The production of TGF-β1 was detected in supernatant of MGC and GES-1. The carboxyfluorescein diacetatesuccinimidyl ester (CFSE) dilution assay was performed to evaluate the proliferation characteristics of induced Tregs. Neutralizing anti-TGF-β1 antibody was added to the co-culture system for neutralization experiments.RESULTS: The level of serum TGF-β1 in gastric cancer patients (15.1 ± 5.5 ng/mL) was significantly higher than that of the gender- and age-matched healthy controls (10.3 ± 3.4 ng/mL) (P < 0.05). Furthermore, the higher TGF-β1 level correlated with the increased population of CD4⁺Foxp3⁺ Tregs in advanced gastric cancer (r = 0.576, P < 0.05). A significant higher frequency of CD4⁺Foxp3⁺ Tregs was observed in PBMCs cultured with the supernatant of MGC than GES-1 (10.6% ± 0.6% vs 8.7% ± 0.7%, P < 0.05). Moreover, using the purified CD4⁺CD25^- T cells, we confirmed that the increased Tregs were mainly induced from the conversation of CD4⁺CD25^- naive T cells, and induced Tregs were functional and able to suppress the proliferation of effector T cells. Finally, we demonstrated that gastric cancer cells induced the increased CD4⁺Foxp3⁺ Tregs via producing TGF-β1. Gastric cancer cells upregulated the production of TGF-β1 and blockade of TGF-β1 partly abrogated Tregs phenotype.CONCLUSION: Gastric cancer cell can induce Tregs development via producing TGF-β1, by which the existence of cross-talk between the tumor and immune cells might regulate anti-tumor immune responses.     

Expansion of CD4+CD25+ regulatory T cells from cord blood CD4+ cells using the common ��-chain cytokines (IL-2 and IL-15) and rapamycin

Rapamycin has important roles in the modulation of regulatory T cells. We tried to expand CD4(+)CD25(+) regulatory T cells (Treg cells) from umbilical cord blood (CB) CD4-positive cells using interleukin (IL)-15 or IL-2 with transforming growth factor (TGF)-β and rapamycin. We were able to obtain more than 500-fold expansion of CD4(+)CD25(+) cells from CB CD4(+) cells using IL-15 and TGF-β with rapamycin. These expanded CD4(+)CD25(+) cells expressed forkhead box P3 (FoxP3) mRNA at a level about 100-fold higher and could suppress allogeneic mixed lymphocyte culture (MLC) by more than 50%. Early after rapamycin stimulation, CB CD4(+) cells showed increased expression of FoxP3 and a serine/threonine kinase Pim2 and sustained expression of negative phosphoinositide 3-kinase regulator phosphatase and tensin homolog deleted on chromosome 10 (PTEN). On the other hand, CD4(+)CD25(+) cells expanded with rapamycin for 8 days showed much higher levels of FoxP3 mRNA expression and decreased expression of PTEN. A comparison of IL-15 stimulation and IL-2 stimulation showed slightly higher efficiency of IL-15 for expansion of CD4(+)CD25(+) cells, and for FoxP3 expression, IL-15 also showed significantly higher efficacy for inhibition of MLC. The combination of the common γ-chain cytokine IL-15, TGF-β, and rapamycin may be a useful means for expanding Treg cells. Pim2 expression early after stimulation with rapamycin may be important for conferring rapamycin resistance for growth of Treg cells. IL-15 is not less useful than IL-2 for expansion of Treg cells.     

β-Catenin in dendritic cells exerts opposite functions in cross-priming and maintenance of CD8+ T cells through regulation of IL-10

Recent studies have demonstrated that β-catenin in DCs serves as a key mediator in promoting both CD4⁺ and CD8⁺ T-cell tolerance, although how β-catenin exerts its functions remains incompletely understood. Here we report that activation of β-catenin in DCs inhibits cross-priming of CD8⁺ T cells by up-regulating mTOR-dependent IL-10, suggesting blocking β-catenin/mTOR/IL-10 signaling as a viable approach to augment CD8⁺ T-cell immunity. However, vaccination of DC–β-catenin^−/− (CD11c-specific deletion of β-catenin) mice surprisingly failed to protect them against tumor challenge. Further studies revealed that DC–β-catenin^−/− mice were deficient in generating CD8⁺ T-cell immunity despite normal clonal expansion, likely due to impaired IL-10 production by β-catenin^−/− DCs. Deletion of β-catenin in DCs or blocking IL-10 after clonal expansion similarly led to reduced CD8⁺ T cells, suggesting that β-catenin in DCs plays a positive role in CD8⁺ T-cell maintenance postclonal expansion through IL-10. Thus, our study has not only identified mTOR/IL-10 as a previously unidentified mechanism for β-catenin–dependent inhibition of cross-priming, but also uncovered an unexpected positive role that β-catenin plays in maintenance of CD8⁺ T cells. Despite β-catenin’s opposite functions in regulating CD8⁺ T-cell responses, selectively blocking β-catenin with a pharmacological inhibitor during priming phase augmented DC vaccine-induced CD8⁺ T-cell immunity and improved antitumor efficacy, suggesting manipulating β-catenin signaling as a feasible therapeutic strategy to improve DC vaccine efficacy.As the initiators of antigen-specific immune responses, dendritic cells (DCs) play a central role in regulating both T-cell immunity and tolerance (1). β-Catenin, a major component in Wnt signaling pathway, has emerged as a key factor in DC differentiation and function (2). Previous studies have shown that β-catenin regulates DC-mediated CD4⁺ T-cell responses and promotes CD4⁺ T-cell tolerance in murine models of autoimmune diseases (3, 4). Consistently, activation of β-catenin in DCs has recently been shown to suppress CD8⁺ T-cell immunity in a DC-targeted vaccine model (5), suggesting that β-catenin in DCs might similarly serve as a tolerizing signal that shifts the balance between CD8⁺ T-cell immunity and tolerance. Although the underlying mechanisms of how β-catenin mediates CD8⁺ T-cell tolerance remain largely unclear, we have shown that activation of β-catenin in DCs genetically or induced by tumors suppresses CD8⁺ T-cell immunity by inhibiting cross-priming (5). Exploiting their ability to potentiate host effector and memory CD8⁺ T-cell responses, DC vaccines have emerged as a leading strategy for cancer immunotherapy (6). However, one major obstacle for their success is host DC-mediated immunosuppression (7–9). Given that cross-priming plays a major role in generating antitumor CD8⁺ T-cell immunity (7, 10), activation of β-catenin in DCs might be a key mechanism for tumors to achieve immunosuppression. Thus, manipulating β-catenin function in cross-priming might be a viable approach to overcome DC-mediated immunosuppression and improve DC vaccine efficacy. However, The underlying mechanisms of how β-catenin in DCs achieves immunosuppression, in particular how β-catenin negatively regulates cross-priming to suppress CD8⁺ T-cell immunity, remain poorly understood.Although the mechanisms for DC-mediated priming of antitumor CD8⁺ T cells through cross-presentation remain incompletely understood, DC subsets, DC maturation status and cytokines have been shown to possibly affect their capacity in cross-priming (7, 10, 11). Although the role of cytokines in cross-priming has not been directly tested, cytokines as “signal 3” have been shown in principal to play a critical role in priming and effector differentiation of antitumor CD8⁺ T cells (12). β-Catenin in DCs has been shown to play a critical role in regulating cytokine induction (3, 4), thus suggesting that β-catenin might regulate DC cytokine production to achieve its effects on cross-priming.In this report we have identified mTOR/IL-10 signaling as a mechanism for β-catenin–dependent inhibition of cross-priming. Activation of β-catenin in DCs inhibited cross-priming of CD8⁺ T cells by up-regulating mTOR-dependent IL-10, and blocking mTOR or IL-10 led to restored cross-priming by β-catenin^active DCs. Surprisingly, mice with DC-specific deletion of β-catenin (DC–β-catenin^−/− mice) exhibited reduced antitumor immunity upon vaccination, despite the fact that deletion of β-catenin in DCs abrogated tumor-induced inhibition of cross-priming. Further studies showed that DC–β-catenin^−/− mice were deficient in generating CD8⁺ T-cell immunity despite normal clonal expansion, and β-catenin in DCs was required to maintain primed CD8⁺ T cells postclonal expansion. Thus, β-catenin in DCs exerts negative and positive functions in cross-priming and maintenance of CD8⁺ T cells, respectively. Importantly, we have demonstrated blocking β-catenin selectively at priming phase as a feasible strategy to improve DC vaccine efficacy.     

TGF-β1 promotes differentiation of hiPSC into functional smooth-muscle-like cells

Background Cell source is one of the most important constructions for tissue engineered blood vessels(TEBV). As human adult vascular cells are limited by the replicative life spans and poor collagen secretion, stem cell has become a promising cell source. Hence, we investigated the differentiation of human induced pluripotent stem cells(hiPSC) into functional smooth-muscle-like cells(SMLCs) by embryoid bodies method and explored whether transforming growth factor-β1(TGF-β1) can promote the differentiation. Methods HiPSCs were cultured in smooth muscle cell medium with or without TGF-β1 after forming embryoid bodies. The cell morphology, cell characteristics and contractility were compared after 7 days of differentiation. Real-time PCR and Western blot were used to assess the mRNA and protein expression levels of α-SMA, Calponin, SM22α, Collagen I and Collagen III. Functional contraction study was performed using carbachol. Results HiPSC could successfully differentiate into cells that were similar to typical smooth muscle cells in morphology. The expression of α-SMA, Calponin and SM22α up-regulated after induction. TGF-β1 could further up-regulated α-SMA expression.Immunofluorescence images showed that more than 80% of the hiPSC-derived SMLCs by TGF-β1 stained with smooth muscle cell markers α-SMA, SMMHC, SM22α and Calponin. Analyses of expression in collagen showed that hiPSC-derived SMLCs exhibited higher levels of Collagen I and Collagen III after induction by TGF-β1. Conclusion The hiPSC could successfully differentiate into smooth-muscle-like cells using embryoid bodies method. TGF-β1 can promote the differentiation and enhance collagen synthesis[.S Chin J Cardiol 2019;20(1):44-53]     

Dietary gluten triggers concomitant activation of CD4+ and CD8+ αβ T cells and γδ T cells in celiac disease

Celiac disease is an intestinal autoimmune disease driven by dietary gluten and gluten-specific CD4⁺ T-cell responses. In celiac patients on a gluten-free diet, exposure to gluten induces the appearance of gluten-specific CD4⁺ T cells with gut-homing potential in the peripheral blood. Here we show that gluten exposure also induces the appearance of activated, gut-homing CD8⁺ αβ and γδ T cells in the peripheral blood. Single-cell T-cell receptor sequence analysis indicates that both of these cell populations have highly focused T-cell receptor repertoires, indicating that their induction is antigen-driven. These results reveal a previously unappreciated role of antigen in the induction of CD8⁺ αβ and γδ T cells in celiac disease and demonstrate a coordinated response by all three of the major types of T cells. More broadly, these responses may parallel adaptive immune responses to viral pathogens and other systemic autoimmune diseases.     

TGF-β1 enhances cardiomyogenic differentiation of skeletal muscle-derived adult primitive cells

The optimal medium for cardiac differentiation of adult primitive cells remains to be established. We quantitatively compared the efficacy of IGF-1, dynorphin B, insulin, oxytocin, bFGF, and TGF-β1 in inducing cardiomyogenic differentiation. Adult mouse skeletal muscle-derived Sca1+/CD45-/c-kit-/Thy-1+ (SM+) and Sca1-/CD45-/c-kit-/Thy-1+ (SM-) cells were cultured in basic medium (BM; DMEM, FBS, IGF-1, dynorphin B) alone and BM supplemented with insulin, oxytocin, bFGF, or TGF-β1. Cardiac differentiation was evaluated by the expression of cardiac-specific markers at the mRNA (qRT-PCR) and protein (immunocytochemistry) levels. BM+TGF-β1 upregulated mRNA expression of Nkx2.5 and GATA-4 after 4 days and Myl2 after 9 days. After 30 days, BM+TGF-β1 induced the greatest extent of cardiac differentiation (by morphology and expression of cardiac markers) in SM- cells. We conclude that TGF-β1 enhances cardiomyogenic differentiation in skeletal muscle-derived adult primitive cells. This strategy may be utilized to induce cardiac differentiation as well as to examine the cardiomyogenic potential of adult tissue-derived stem/progenitor cells. Electronic supplementary material  The online version of this article (DOI:) contains supplementary material, which is available to authorized users. Returned for 1. Revision: 8 January 2008 1. Revision received: 8 April 2008 Ahmed Abdel-Latif and Ewa K. Zuba-Surma contributed equally to this work.     

IFN-α and CD46 stimulation are associated with active lupus and skew natural T regulatory cell differentiation to type 1 regulatory T (Tr1) cells

Immune suppressive activities exerted by regulatory T-cell subsets have several specific functions, including self-tolerance and regulation of adaptive immune reactions, and their dysfunction can lead to autoimmune diseases and contribute to AIDS and cancer. Two functionally distinct regulatory T-cell subsets are currently identified in peripheral tissues: thymus-developed natural T regulatory cells (nTregs) controlling self-tolerance and antiinflammatory IL-10-secreting type 1 regulatory T cells (Tr1) derived from Ag-stimulated T cells, which regulate inflammation-dependent adaptive immunity and minimize immunopathology. We establish herein that cell contact-mediated nTreg regulatory function is inhibited by inflammation, especially in the presence of the complement C3b receptor (CD46). Instead, as with other T-cell subsets, the latter inflammatory conditions of stimulation skew nTreg differentiation to Tr1 cells secreting IL-10, an effect potentiated by IFN-α. The clinical relevance of these findings was verified in a study of 152 lupus patients, in which we showed that lupus nTreg dysfunction is not due to intrinsic defects but is rather induced by C3b stimulation of CD46 and IFN-α and that these immune components of inflammation are directly associated with active lupus. These results provide a rationale for using anti-IFN-α Ab immunotherapy in lupus patients.     

Generation of Th17 cells in response to intranasal infection requires TGF-β1 from dendritic cells and IL-6 from CD301b+ dendritic cells

Intranasal (i.n.) infections preferentially generate Th17 cells. We explored the basis for this anatomic preference by tracking polyclonal CD4⁺ T cells specific for an MHC class II-bound peptide from the mucosal pathogen Streptococcus pyogenes. S. pyogenes MHC class II-bound peptide-specific CD4⁺ T cells were first activated in the cervical lymph nodes following i.n. inoculation and then differentiated into Th17 cells. S. pyogenes-induced Th17 formation depended on TGF-β1 from dendritic cells and IL-6 from a CD301b⁺ dendritic cell subset located in the cervical lymph nodes but not the spleen. Thus, the tendency of i.n. infection to induce Th17 cells is related to cytokine production by specialized dendritic cells that drain this site.Th17 cells are a subset of CD4⁺ helper T cells that orchestrate protective immunity to extracellular bacterial and fungal pathogens, predominantly at epithelial surfaces (1). T-cell antigen receptor (TCR) recognition of an MHC class II-bound peptide (p:MHCII) on an antigen-presenting cell causes Th17 cells to secrete the signature cytokine IL-17A, which acts primarily by increasing chemokine production in epithelial tissues to enable the recruitment, activation, and migration of neutrophils and monocytes (1).In vitro studies have shown that naive CD4⁺ T cells differentiate into Th17 cells when stimulated by p:MHCII ligands in the presence of transforming growth factor-β1 (TGF-β1) and IL-6 (2-4). Similarly, TGF-β1 is required for Th17 differentiation during the induction of experimental autoimmune encephalomyelitis (EAE) (5). Th17 cells are also generated during intranasal (i.n.) infection by Streptococcus pyogenes, and TGF-β1 receptor signaling and IL-6 are involved (6, 7). However, Th17 cell formation in the small intestine does not depend on TGF-β1 (8) and requires IL-1β but not IL-6 (9). Additionally, Kuchroo and colleagues reported that although Th17 differentiation was normally dependent on IL-6, it could occur without it through an IL-21–dependent pathway if regulatory T cells were absent (10).Infection via the i.n. route may induce Th17 cells because nasal-associated lymphoid tissue (NALT) contains specialized antigen-presenting cells that preferentially produce IL-1β or IL-6 and TGF-β1. Here, we tested this idea by studying the primary immune response to i.n. infection with S. pyogenes bacteria (11). We found that S. pyogenes p:MHCII-specific Th17 cell formation depended on TGF-β1 from dendritic cells and IL-6 from a CD301b⁺ dendritic cell subset located in the cervical lymph nodes (CLNs) but not the spleen.     

Increased CD4+CD16+ and CD4+CD56+ T cell subsets in Behçet's disease

Behçet's disease is a systemic vasculitis of unknown etiology. Various immune abnormalities have previously been shown in Behçet's disease. We investigated T lymphocyte subsets associated with cytotoxic activity and natural killer (NK) cells by flow cytometry in 37 patients with Behçet's disease, 38 healthy controls, and 17 diseased control patients. Compared to the healthy controls, CD4⁺CD16⁺ and CD4⁺CD56⁺ subsets were found to be higher in the Behçet's disease group as well as in the disease control group (CD4⁺CD16⁺: BD=5?±?3, DC=14?±?14, HC= 3?±?2, P=0.001; CD4⁺CD56⁺: BD=11?±?5, DC= 18?±?17, HC=8?±?6, P=0.01). CD8⁺CD16⁺ and CD8⁺CD56⁺ T cell subsets were at normal levels in Behçet's disease but found to be elevated in disease controls. Similarly, NK cells (CD16⁺CD56⁺) were high only in the disease control group. Significant increases in CD4⁺CD16⁺ and CD4⁺CD56⁺ cell subsets in Behçet's patients and disease controls suggest that T cell activation patterns of these subsets in Behçet's disease are similar to those in other inflammatory disorders.     

The dominant human conjunctival epithelial CD8αβ+ T cell population is maintained with age but the number of CD4+ T cells increases

The conjunctiva is a highly specialized ocular mucosal surface that, like other mucosa, houses a number of leukocyte populations. These leukocytes have been implicated in age-related inflammatory diseases such as dry-eye, but their phenotypic characteristics remain largely undetermined. Existing literature provides rudimentary data from predominantly immunohistochemical analyses of tissue sections, prohibiting detailed and longitudinal examination of these cells in health and disease. Using recovered cells from ocular surface impression cytology and flow cytometry, we examined the frequency of leukocyte subsets in human conjunctival epithelium and how this alters with age. Of the total CD45+ leukocyte population within the conjunctival epithelium, 87% [32–99] (median) [range] comprised lymphocytes, with 69% [47–90] identified as CD3 + CD56- T cells. In contrast to peripheral blood, the dominant conjunctival epithelial population was TCRαβ + CD8αβ + (80% [37–100]) with only 10% [0-56%] CD4+ cells. Whilst a significant increase in the CD4+ population was seen with age (r = 0.5; p < 0.01) the CD8+ population remained unchanged, resulting in an increase in the CD4:CD8 ratio (r = 0.5;p < 0.01). IFNγ expression was detectable in 18% [14–48] of conjunctival CD4+ T cells and this was significantly higher among older individuals (<35 years, 7[4–39] vs. >65 years, 43[20–145]; p < 0.05). The elevation of CD4+ cells highlights a potentially important age-related alteration in the conjunctival intra-epithelial leukocyte population, which may account for the vulnerability of the aging ocular surface to disease.     

Commensal microbes drive intestinal inflammation by IL-17–producing CD4+ T cells through ICOSL and OX40L costimulation in the absence of B7-1 and B7-2

The costimulatory B7-1 (CD80)/B7-2 (CD86) molecules, along with T-cell receptor stimulation, together facilitate T-cell activation. This explains why in vivo B7 costimulation neutralization efficiently silences a variety of human autoimmune disorders. Paradoxically, however, B7 blockade also potently moderates accumulation of immune-suppressive regulatory T cells (Tregs) essential for protection against multiorgan systemic autoimmunity. Here we show that B7 deprivation in mice overrides the necessity for Tregs in averting systemic autoimmunity and inflammation in extraintestinal tissues, whereas peripherally induced Tregs retained in the absence of B7 selectively mitigate intestinal inflammation caused by Th17 effector CD4⁺ T cells. The need for additional immune suppression in the intestine reflects commensal microbe-driven T-cell activation through the accessory costimulation molecules ICOSL and OX40L. Eradication of commensal enteric bacteria mitigates intestinal inflammation and IL-17 production triggered by Treg depletion in B7-deficient mice, whereas re-establishing intestinal colonization with Candida albicans primes expansion of Th17 cells with commensal specificity. Thus, neutralizing B7 costimulation uncovers an essential role for Tregs in selectively averting intestinal inflammation by Th17 CD4⁺ T cells with commensal microbe specificity.Immune activation is stringently controlled to balance mobilization of protective components while simultaneously silencing detrimental responses that cause harm to host tissues. One means of regulation is the additional necessity for B7-1 (CD80)/B7-2 (CD86) costimulatory signals, along with T-cell receptor stimulation, in T-cell activation (1). Reciprocally, soluble recombinant formulations of the natural high-affinity B7 ligand—cytotoxic T-lymphocyte antigen 4 fused with human Ig (CTLA4-Ig), which blocks B7 costimulation—are efficacious in neutralizing aberrant T-cell activation in autoimmune disorders such as rheumatoid arthritis and juvenile idiopathic arthritis (2). Ongoing studies suggest that these therapeutic benefits also extend to many other types of autoimmunity including psoriasis, systemic lupus erthematosus, multiple sclerosis, and type 1 diabetes (3–6). Interestingly, however, the protective benefits of B7 blockade are not universal as CTLA4-Ig is distinctively nonefficacious for inflammatory bowel disease (7) and can induce intestinal inflammation among individuals with unrelated autoimmune disorders (8).Given that B7 costimulation required for T-cell activation also sustains accumulation of immune-suppressive regulatory T cells (Tregs) essential for averting fatal systemic autoimmunity (9, 10), this discordance in therapeutic efficacy with B7 blockade may reflect tissue-specific differences in necessity for Treg suppression in the absence of B7 costimulation. Here, unique features of the intestine that include high-density commensal bacteria colonization or expression of the accessory costimulatory molecules ICOS ligand (ICOSL) or OX40 ligand (OX40L) may foster susceptibility to inflammation despite B7 deprivation (11–15). To investigate these possibilities, the interplay between Tregs and B7, ICOSL, and OX40L costimulation in autoimmunity was evaluated after targeted ablation of each individually or concurrently. Our results show that B7 deprivation overrides the necessity for Tregs in averting systemic autoimmunity and inflammation in extraintestinal tissues, whereas enteric commensal microbes drive inflammation restricted to the intestine through ICOSL/OX40L stimulation when Tregs and B7 are simultaneously eliminated. These results illustrating persistent intestinal inflammation despite B7 deprivation may explain why inflammatory bowel disease, compared with other forms of autoimmunity, is distinctively resistant to B7 blockade.     

TGF-β/Smad signaling pathway positively up-regulates the differentiation of Interleukin-9-producing CD4+ T cells in human Echinococcus granulosus infection

Objectives

Cystic echinococcosis (CE) is a zoonotic disease caused by Echinococcus granulosus (Eg) infection. Th9 cells are reported to be involved in the immune responses in CE patients. This study aims to investigate the role of TGF-β/Smad pathway in the regulation of Th9 cells in CE patients.

Associations of circulating CXCR3–PD-1+CD4+T cells with disease activity of systemic lupus erythematosus

Abstract

Objectives: Which helper CD4⁺ T cell subset contributes to autoantibodies generation and severity of end-organ involvement in lupus patients remains to be explored. Our research aims to investigate the roles of circulating Tfh (cTfh) cell subsets and corresponding CXCR5^– Th cells in lupus patients and their correlation with SLE disease activity index 2000 (SLEDAI).

Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from blood of systemic lupus erythematosus (SLE) patients as well as healthy donors. The proportion of Th cell subsets classified from cell surface markers (CD45RO, CXCR5, CXCR3, CCR6, PD-1, ICOS, and CCR7) is detected by flow cytometry.

Results: We found no difference in the frequency of CD45RO⁺CXCR5⁺CD4⁺ T cells between SLE patients and health controls. As previously reported, SLE patients showed an increase in the percentage of CXCR5⁺PD-1⁺, CXCR5⁺ICOS⁺PD-1⁺ and CXCR5⁺CCR7^loPD-1^hi cTfh subset, however, none of these populations had correlation with SLEDAI. Therefore, we further investigated the CXCR5^– subsets, and surprisingly we found that the frequency of CXCR3^–PD-1⁺ subset was correlated with SLEDAI, ds-DNA IgG, anti-nucleosome antibody, C3, and C4 independent of CXCR5. Consistently, CXCR3^–PD-1⁺CD45RO⁺CD4⁺T cells expressed factors associated with B-cell-help for the autoantibody production.

Conclusion: CXCR3^–PD-1⁺CD4⁺T cells are a sensitive indicator to assess SLE disease activity and might contribute B cell help and the generation of autoantibodies in patients.     

Modification of TGF-β1 signaling pathway during NB4 cells differentiation by all-trans retinoid acid induction

The aim of the study was to present the possible mechanisms of transforming growth factor beta 1(TGF-β1) signal pathway during cell differentiation by studying the expression levels of six components of TGF-β1 pathway (TGF-β1, two TGF-β1 receptors and three Smad proteins). The morphology change, the CD11 expression levels, and the mRNA and protein expression levels of TGF-β1, TGF-β ReceptorI (TβRI), TGF-β ReceptorII (TβRII), Smad2, Smad4 and Smad7 were assessed by exposing NB4 cells to all-trans retinoid acid (ATRA) using Wright’s stain, flow cytometry, real-time PCR assay and Western blot analysis. The mRNA and protein expression levels of all six components increased during NB4 cells differentiation induced by ATRA. They were most significantly increased after 24–72 h individually when cells were induced by ATRA (the mRNA and protein expression levels of TGF-β1, TβRI, TβRII and Smad2 reached their peaks at 48 and 48 h individually after the treatment, Smad4 at 48 and 72 h, and Smad7 at 72 and 72 h). The change in mRNA expression levels was earlier than the change in the same gene controlling protein. These results indicate that the upregulation of TGF-β1 pathway plays an important role in NB4 cells differentiation induced by ATRA.     

CD4+CD25+Treg细胞、TGF-β1和IL-10在上皮性卵巢癌中的变化

目的 研究上皮性卵巢癌患者外周血中CD4+ CD25+调节性T细胞数量及其相关基因Foxp3 mRNA的表达,同时检测抑制性细胞因子TGF-β1及IL-10的表达,探讨CD4+ CD25+调节性T细胞在诱导肿瘤免疫耐受中的作用.方法 采用流式细胞术检测卵巢浆液性囊腺癌和黏液性囊腺癌患者外周血中CD4+ CD25+调节性T细胞数量变化;采用半定量RT-PCR方法检测卵巢浆液性囊腺癌和黏液性囊腺癌患者外周血PBMC中Foxp3 mRNA表达水平.应用ELISA方法测定上皮性卵巢癌患者外周血清TGF-β1及IL-10浓度.结果 卵巢浆液性囊腺癌和黏液性囊腺癌患者外周血中CD4+ CD25+调节性T细胞数量均明显升高(P＜0.05);Foxp3 mRNA在卵巢浆液性囊腺癌和黏液性囊腺癌患者外周血中表达明显增高(P＜0.05).卵巢浆液性囊腺癌和黏液性囊腺癌患者外周血中TGF-β1及IL-10的表达均明显增强.结论 CD4+ CD25+调节性T细胞可能在卵巢癌免疫耐受中发挥重要作用.     

In vivo dynamics of T cell activation,proliferation, and death in HIV-1 infection: why are CD4+ but not CD8+ T cells depleted?

Deuterated glucose labeling was used to measure the in vivo turnover of T lymphocytes. A realistic T cell kinetic model, with populations of resting and activated T cells, was fitted to d-glucose labeling data from healthy and HIV-1-infected individuals before and after antiretroviral treatment. Our analysis highlights why HIV-1 infection, which increases the fraction of both CD4(+) and CD8(+) T lymphocytes that are proliferating (Ki67(+)), leads to CD4 but not CD8 depletion. We find that HIV-1 infection tends to increase the rates of death and proliferation of activated CD4(+) T cells, and to increase the rate at which resting CD4 T cells become activated, but does not increase the fraction of activated CD4(+) T cells, consistent with their preferential loss in HIV-1-infected individuals. In contrast, HIV-1 infection does not lead to an increase in proliferation or death rates of activated CD8(+) T cells, but did increase the fraction of activated CD8(+) T cells, consistent with these cells remaining in an activated state longer and undergoing more rounds of proliferation than CD4(+) T cells. Our results also explain why telomeres shorten in CD8(+) cells, but not in CD4(+) cells of HIV-1-infected patients, compared with age-matched controls.