Objective To explore the phenotypic conversion of regulatory T cells (Tregs) in the lungs of mice with bronchopulmonary dysplasia (BPD)-affected mice. Methods A total of 20 newborn C57BL/6 mice were divided into air group and hyperoxia group, with 10 mice in each group. The BPD model was established by exposing the newborn mice to hyperoxia. Lung tissues from five mice in each group were collected on postnatal days 7 and 14, respectively. Histopathological changes of the lung tissues was detected by HE staining. The expression level of surfactant protein C (SP-C) in the lung tissues was examined by Western blot analysis. Flow cytometry was performed to assess the proportion of FOXP3⁺ Tregs and RORγt⁺FOXP3⁺ Tregs in CD4⁺ lymphocytes. The concentrations of interleukin-17A (IL-17A) and IL-6 in lung homogenate were measured by using ELISA. Spearman correlation analysis was used to analyze the correlation between FOXP3⁺Treg and the expression of SP-C and the correlation between RORγt⁺FOXP3⁺ Tregs and the content of IL-17A and IL-6. Results The hyperoxia group exhibited significantly decreased levels of SP-C and radical alveolar counts in comparison to the control group. The proportion of FOXP3⁺Tregs was reduced and that of RORγt⁺FOXP3⁺Tregs was increased. IL-17A and IL-6 concentrations were significantly increased. SP-C was positively correlated with the expression level of RORγt⁺FOXP3⁺ Tregs. RORγt⁺FOXP3⁺ Tregs and IL-17A and IL-6 concentrations were also positively correlated. Conclusion The number of FOXP3⁺ Tregs in lung tissue of BPD mice is decreased and converted to RORγt⁺ FOXP3⁺ Tregs, which may be involved in hyperoxy-induced lung injury.
Animals ; Mice ; Mice, Inbred C57BL ; Bronchopulmonary Dysplasia ; T-Lymphocytes, Regulatory ; Interleukin-17 ; Nuclear Receptor Subfamily 1, Group F, Member 3 ; Hyperoxia ; Interleukin-6 ; Forkhead Transcription Factors ; Lung

In the tumor microenvironment, metabolic reprogramming can impact metabolic characteristics of T cells, thus inducing immunosuppression to promote tumor immune escape. The mammalian target of rapamycin (mTOR) signaling pathway plays an important role in regulating diverse functions of various immune cells. This review mainly focuses on the molecular mechanism of mTOR signaling in regulating cellular energy metabolism process, and the activation status of mTOR signaling under different nutritional environments. In addition, it also summarizes the role of the mTOR signaling in regulatory T cell (Tregs) metabolism and function in current studies, and evaluates the potential of mTOR as a clinical immunotherapeutic target and its current application challenges.
Immunosuppression Therapy ; Metabolic Reprogramming ; Signal Transduction ; Sirolimus ; T-Lymphocytes, Regulatory ; TOR Serine-Threonine Kinases ; Humans

Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease, mediated by pathogenic T helper 17 (Th17) cells. However, the therapeutic effect is accompanied by the fluctuation of the proportion and function of Th17 cells, which prompted us to find the key regulator of Th17 differentiation in MS. Here, we demonstrated that the triggering receptor expressed on myeloid cells 2 (TREM-2), a modulator of pattern recognition receptors on innate immune cells, was highly expressed on pathogenic CD4-positive T lymphocyte (CD4⁺ T) cells in both patients with MS and experimental autoimmune encephalomyelitis (EAE) mouse models. Conditional knockout of Trem-2 in CD4⁺ T cells significantly alleviated the disease activity and reduced Th17 cell infiltration, activation, differentiation, and inflammatory cytokine production and secretion in EAE mice. Furthermore, with Trem-2 knockout in vivo experiments and in vitro inhibitor assays, the TREM-2/zeta-chain associated protein kinase 70 (ZAP70)/signal transducer and activator of transcription 3 (STAT3) signal axis was essential for Th17 activation and differentiation in EAE progression. In conclusion, TREM-2 is a key regulator of pathogenic Th17 in EAE mice, and this sheds new light on the potential of this therapeutic target for MS.
Animals ; Humans ; Mice ; CD4-Positive T-Lymphocytes/pathology* ; Cell Differentiation ; Encephalomyelitis, Autoimmune, Experimental/metabolism* ; Mice, Inbred C57BL ; Multiple Sclerosis ; Th1 Cells/pathology*

OBJECTIVE: To investigate the distribution of bone marrow lymphocyte subsets in patients with myelodysplastic syndrome(MDS),the proportion of activated T cells with immunophenotype CD3⁺HLA-DR⁺ in the lymphocytes and its clinical significance, and to understand the effects of different types of MDS, different immunophenotypes, and different expression levels of WT1 on the proportion of lymphocyte subsets and activated T cells. METHODS: The immunophenotypes of 96 MDS patients, the subsets of bone marrow lymphocytes and activated T cells were detected by flow cytometry. The relative expression of WT1 was detected by real-time fluorescent quantitative PCR, and the first induced remission rate (CR1) was calculated, the differences of lymphocyte subsets and activated T cells in MDS patients with different immunophenotype, different WT1 expression, and different course of disease were analyzed. RESULTS: The percentage of CD4⁺T lymphocyte in MDS-EB-2, IPSS high-risk, CD34⁺ cells >10%, and patients with CD34⁺CD7⁺ cell population and WT1 gene overexpression at intial diagnosis decreased significantly (P<0.05), and the percentage of NK cells and activated T cells increased significantly (P<0.05), but there was no significant difference in the ratio of B lymphocytes. Compared with the normal control group, the percentage of NK cells and activated T cells in IPSS-intermediate-2 group was significantly higher(P<0.05), but there was no significant difference in the percentage of CD3⁺T, CD4⁺T lymphocytes. The percentage of CD4⁺T cells in patients with complete remission after the first chemotherapy was significantly higher than in patients with incomplete remission(P<0.05), and the percentage of NK cells and activated T cells was significantly lower than that in patients with incomplete remission (P<0.05). CONCLUSION In MDS patients, the proportion of CD3⁺T and CD4⁺T lymphocytes decreased, and the proportion of activated T cells increased, indicating that the differentiation type of MDS is more primitive and the prognosis is worse.
Humans ; Lymphocyte Subsets ; Myelodysplastic Syndromes/diagnosis* ; Bone Marrow ; B-Lymphocytes ; Killer Cells, Natural ; Flow Cytometry ; T-Lymphocyte Subsets

OBJECTIVE: To investigate the expression and significance of regulatory T cells (Tregs), FoxP3 and transforming growth factor-β (TGF-β) in different phase of chronic myeloid leukemia (CML). METHODS: Peripheral blood of 73 CML patients in Department of Hematology, Heze Municipal Hospital from March 2018 to March 2021 were collected. According to patient's period in CML, they were divided into ND CML group (newly diagnosed), CP CML group (chronic period), and BP CML group (blast phase). The percentage of Tregs, expression level of FoxP3 mRNA and TGF-β were detected by flow cytometry, RT-qPCR, and ELISA, respecitively. The roles of above indices in clinical pathogenesis of patients with CML were analyzed. RESULTS: The proportion of Treg in the ND CML group was slightly higher than the CP CML group, but the difference was not statistically significant (P =0.695), while the BP CML group was significantly higher than the other two groups (P =0.008, P <0.001). The expression levels of FoxP3 mRNA in ND CML group, CP CML group and BP CML group were 11.61±2.21, 6.46±1.35 and 8.54±2.13, respectively. Significant difference in FoxP3 mRNA levels was observed among patients in different phases of CML (F =55.199, P <0.001). The expression levels of FoxP3 mRNA both in ND CML group and BP CML group were significantly higher than that in CP CML group (P <0.001), and the ND CML group was the highest (P <0.001). However, the expression levels of TGF-β in different phases of CML showed no statistical differences (H =0.634, P =0.728). CONCLUSION The abnormal distribution of Treg subset in different phases of CML and the significant increase of the expression level of FoxP3 mRNA in the new onset and blast phase of CML suggest that Tregs may promote the occurrence and progression of CML through immune regulation.
Humans ; Blast Crisis/metabolism* ; Forkhead Transcription Factors/metabolism* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics* ; RNA, Messenger/metabolism* ; T-Lymphocytes, Regulatory/metabolism* ; Transforming Growth Factor beta/metabolism*

OBJECTIVE: To examine the anti-inflammatory effect of grape seed extract (GSE) in animal and cellular models and explore its mechanism of action. METHODS: This study determined the inhibitory effect of GSE on macrophage inflammation and Th1 and Th17 polarization in vitro. Based on the in vitro results, the effects and mechanisms of GSE on multiple sclerosis (MS)-experimental autoimmune encephalomyelitis (EAE) mice model were further explored. The C57BL/6 mice were intragastrically administered with 50 mg/kg of GSE once a day from the 3rd day to the 27th day after immunization. The activation of microglia, the polarization of Th1 and Th17 and the inflammatory factors such as tumor necrosis factor- α (TNF- α), interleukin-1 β (IL-1 β), IL-6, IL-12, IL-17 and interferon-γ (IFN-γ) secreted by them were detected in vitro and in vivo by flow cytometry, enzyme linked immunosorbent assay (ELISA), immunofluorescence staining and Western blot, respectively. RESULTS: GSE reduced the secretion of TNF-α, IL-1 β and IL-6 in bone marrow-derived macrophages stimulated by lipopolysaccharide (P<0.01), inhibited the secretion of TNF-α, IL-1 β, IL-6, IL-12, IL-17 and IFN-γ in spleen cells of EAE mice immunized for 9 days (P<0.05 or P<0.01), and reduced the differentiation of Th1 and Th17 mediated by CD3 and CD28 factors (P<0.01). GSE significantly improved the clinical symptoms of EAE mice, and inhibited spinal cord demyelination and inflammatory cell infiltration. Peripherally, GSE downregulated the expression of toll-like-receptor 4 (TLR4) and Rho-associated kinase (ROCKII, P<0.05 or P<0.01), and inhibited the secretion of inflammatory factors (P<0.01 or P<0.05). In the central nervous system, GSE inhibited the infiltration of CD45⁺CD11b⁺ and CD45⁺CD4⁺ cells, and weakened the differentiation of Th1 and Th17 (P<0.05). Moreover, it reduced the secretion of inflammatory factors (P<0.01), and prevented the activation of microglia (P<0.05). CONCLUSION GSE had a beneficial effect on the pathogenesis and progression of EAE by inhibiting inflammatory response as a potential drug and strategy for the treatment of MS.
Mice ; Animals ; Encephalomyelitis, Autoimmune, Experimental/pathology* ; Grape Seed Extract/therapeutic use* ; Interleukin-17 ; Interleukin-1beta ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Th1 Cells ; Mice, Inbred C57BL ; Interferon-gamma/therapeutic use* ; Th17 Cells/metabolism* ; Interleukin-12/therapeutic use* ; Cytokines/metabolism*

Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen's method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)‍-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17⁺ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17⁺ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the "gut-spinal cord-immune" axis may be one of the mechanisms regulating neural repair after SCI.
Animals ; Rats ; Interleukin-17 ; Rats, Sprague-Dawley ; Recovery of Function ; Spinal Cord Injuries/drug therapy* ; T-Lymphocytes, Regulatory ; Receptors, Antigen, T-Cell, gamma-delta/immunology*

Objective: T lymphocyte exhaustion is an important component of immune dysfunction. Therefore, exploring peripheral blood-exhausted T lymphocyte features in patients with hepatitis B virus-related acute-on-chronic liver failure may provide potential therapeutic target molecules for ACLF immune dysfunction. Methods: Six cases with HBV-ACLF and three healthy controls were selected for T-cell heterogeneity detection using the single-cell RNA sequencing method. In addition, exhausted T lymphocyte subpopulations were screened to analyze their gene expression features, and their developmental trajectories quasi-timing. An independent sample t-test was used to compare the samples between the two groups. Results: Peripheral blood T lymphocytes in HBV-ACLF patients had different differentiation trajectories with different features distinct into eight subpopulations. Among them, the CD4(+)TIGIT(+) subsets (P = 0.007) and CD8(+)LAG3(+) (P = 0.010) subsets with highly exhausted genes were significantly higher than those in healthy controls. Quasi-time analysis showed that CD4(+)TIGIT(+) and CD8(+)LAG3(+) subsets appeared in the late stage of T lymphocyte differentiation, suggesting the transition of T lymphocyte from naïve-effector-exhausted during ACLF pathogenesis. Conclusion: There is heterogeneity in peripheral blood T lymphocyte differentiation in patients with HBV-ACLF, and the number of exhausted T cells featured by CD4(+)TIGIT(+)T cell and CD8(+)LAG3(+) T cell subsets increases significantly, suggesting that T lymphocyte immune exhaustion is involved in the immune dysfunction of HBV-ACLF, thereby identifying potential effective target molecules for improving ACLF patients' immune function.
Humans ; Hepatitis B virus ; Acute-On-Chronic Liver Failure/pathology* ; Hepatitis B, Chronic ; T-Lymphocyte Subsets/pathology* ; Receptors, Immunologic

Objective: To investigate the effects of combined blockade of interleukin-33 (IL-33) and inducible co-stimulatory molecule (ICOS) on carbon tetrachloride-induced chronic liver fibrosis and imbalance of T helper lymphocyte subsets in mice. Methods: There were 40 BALB/c mice in each model and control group. Flow cytometry was used to determine the proportion of Th1/Th2/Th17 cells in the splenic lymphocyte suspension of mice, the expression levels of interferon γ, IL-4, and IL-17 in the splenic lymphocyte suspension of liver fibrosis mice after combined blockade of IL-33 and ICOS, and the pathological changes of liver histopathology in mice with liver fibrosis. Two independent sample t-test was used to compare data between groups. Results: Compared with the non-blocking group, the proportion of Th2 and Th17 cells in the IL-33/ICOS blocking group was significantly down-regulated (Th2: 65.96% ± 6.04% vs. 49.09% ± 7.03%; Th17: 19.17% ± 4.03% vs. 9.56% ± 2.03%), while the proportion of Th1 cells and Th1/Th2 ratio were up-regulated (Th1: 17.14% ± 3.02% vs. 31.93% ± 5.02%; Th1/Th2: 0.28 ± 0.06 vs. 0.62 ± 0.23), and the difference was statistically significant (t = 5.15, 6.03, 7.14, 4.28, respectively, with P < 0.05). After entering the chronic inflammation stage of liver fibrosis in mice (10 weeks), compared with the non-blocking group, the expression levels of IL-4 and IL-17 in the blockade group were significantly down-regulated [IL-4: (84.75 ± 14.35) pg/ ml vs. (77.88 ± 19.61) pg/ml; IL-17: (72.38 ± 15.13) pg/ml vs. (36.38 ± 8.65) pg/ml], while the expression of interferon γ was up-regulated [(37.25 ± 11.51) pg/ml vs. (77.88 ± 19.61) pg/ml], and the difference was statistically significant (t: IL-4: 4.71; IL-17: 5.84; interferon γ: 5.05, respectively, with P < 0.05). Liver histopathological results showed that hepatic necrosis, hepatic lobular structural disorder, and fibrous tissue hyperplasia were significantly lower in the blockade group than those in the non-blocking group at 13 weeks of liver fibrosis. Conclusion: Combined blockade of the ICOS signaling pathway and IL-33 can regulate Th2 and Th17 polarization, down-regulate the inflammatory response, and inhibit or prevent the occurrence and progression of fibrosis.
Mice ; Animals ; Interferon-gamma/metabolism* ; Interleukin-17/metabolism* ; Interleukin-33/metabolism* ; Cytokines/metabolism* ; Carbon Tetrachloride ; Th2 Cells ; Interleukin-4/metabolism* ; Liver Cirrhosis/pathology* ; Th1 Cells ; Th17 Cells/pathology* ; Immunity

OBJECTIVE: To analyze the clinicopathological features, molecular changes and prognostic factors in angioimmunoblastic T-cell lymphoma (AITL). METHODS: Sixty-one cases AITL diagnosed by Department of Pathology of Peking University Cancer Hospital were collected with their clinical data. Morphologically, they were classified as typeⅠ[lymphoid tissue reactive hyperplasia (LRH) like]; typeⅡ[marginal zone lymphoma(MZL)like] and type Ⅲ [peripheral T-cell lymphoma, not specified (PTCL-NOS) like]. Immunohistochemical staining was used to evaluate the presence of follicular helper T-cell (TFH) phenotype, proliferation of extra germinal center (GC) follicular dendritic cells (FDCs), presence of Hodgkin and Reed-Sternberg (HRS)-like cells and large B transformation. The density of Epstein-Barr virus (EBV) + cells was counted with slides stained by Epstein-Barr virus encoded RNA (EBER) in situ hybridization on high power field (HPF). T-cell receptor / immunoglobulin gene (TCR/IG) clonality and targeted exome sequencing (TES) test were performed when necessary. SPSS 22.0 software was used for statistical analysis. RESULTS: Morphological subtype (%): 11.4% (7/61) cases were classified as type Ⅰ; 50.8% (31/61) as type Ⅱ; 37.8% (23/61) as type Ⅲ. 83.6% (51/61) cases showed classical TFH immunophenotype. With variable extra-GC FDC meshwork proliferation (median 20.0%); 23.0% (14/61) had HRS-like cells; 11.5% (7/61) with large B transformation. 42.6% (26/61) of cases with high counts of EBV. 57.9% (11/19) TCR⁺/IG^-, 26.3% (5/19) TCR⁺/IG⁺, 10.5% (2/19) were TCR^－/IG^－, and 5.3% (1/19) TCR^－/IG⁺. Mutation frequencies by TES were 66.7% (20/30) for RHOA, 23.3% (7/30) for IDH2 mutation, 80.0% (24/30) for TET2 mutation, and 33.3% (10/30) DNMT3A mutation. Integrated analysis divided into four groups: (1) IDH2 and RHOA co-mutation group (7 cases): 6 cases were type Ⅱ, 1 case was type Ⅲ; all with typical TFH phenotype; HRS-like cells and large B transformation were not found; (2) RHOA single mutation group (13 cases): 1 case was type Ⅰ, 6 cases were type Ⅱ, 6 cases were type Ⅲ; 5 cases without typical TFH phenotype; 6 cases had HRS-like cells, and 2 cases with large B transformation. Atypically, 1 case showed TCR^－/IG^－, 1 case with TCR^－/IG⁺, and 1 case with TCR⁺/IG⁺; (3) TET2 and/or DNMT3A mutation alone group (7 cases): 3 cases were type Ⅱ, 4 cases were type Ⅲ, all cases were found with typical TFH phenotype; 2 cases had HRS-like cells, 2 cases with large B transformation, and atypically; (4) non-mutation group (3 cases), all were type Ⅱ, with typical TFH phenotype, with significant extra-GC FDC proliferation, without HRS-like cells and large B transformation. Atypically, 1 case was TCR^－/IG^－. Univariate analysis confirmed that higher density of EBV positive cell was independent adverse prognostic factors for both overall survival (OS) and progression free survival(PFS), (P=0.017 and P=0.046). CONCLUSION Pathological diagnoses of ALTL cases with HRS-like cells, large B transformation or type Ⅰ are difficult. Although TCR/IG gene rearrangement test is helpful but still with limitation. TES involving RHOA, IDH2, TET2, DNMT3A can robustly assist in the differential diagnosis of those difficult cases. Higher density of EBV positive cells counts in tumor tissue might be an indicator for poor survival.
Humans ; Epstein-Barr Virus Infections/genetics* ; Herpesvirus 4, Human/genetics* ; T-Lymphocytes, Helper-Inducer/pathology* ; Immunoblastic Lymphadenopathy/pathology* ; Lymphoma, T-Cell, Peripheral/pathology* ; Receptors, Antigen, T-Cell