1.Straddling Two Lineages: Mixed-Phenotype Acute Leukemia, B/T (MPAL-B/T) in a 12-year-old Filipino Male
Dan Angelo D. Matias ; Francisco P. Tria IV ; Daphne C. Ang
Philippine Journal of Pathology 2026;(75th PSP Research Competition Abstracts):1-
Introduction:
Mixed-phenotype acute leukemia (MPAL) is a rare, biologically highrisk acute leukemia characterized by blasts expressing markers of more than one
hematopoietic lineage. It accounts for <4% of acute leukemias. MPAL with B- and
T-lineage differentiation (MPAL-B/T) is exceptionally rare, comprising ~6% of MPAL
cases, with limited pediatric reports. Accurate recognition is critical, as this entity
carries distinct therapeutic and prognostic implications compared with lineage-defined
leukemias.
Case Presentation:
We report a 12-year-old Filipino female presenting with epistaxis,
pallor, and easy bruising. Laboratory studies revealed severe anemia, hyperleukocytosis,
and circulating blasts. Peripheral blood flow cytometry revealed 73% blasts co-expressing
T-lineage markers (surface and cytoplasmic CD3, CD5, CD7) and B-lineage markers
(CD19, cytoplasmic CD79a), with CD34 and HLA-DR. Bone marrow flow cytometry
confirmed persistent dual-lineage expression in blasts comprising 21% of total events.
Discussion:
The findings meet WHO diagnostic criteria for MPAL, with definitive
T-lineage assignment via cCD3 and strong B-lineage expression with CD19 and
cCD79a. By European Group for the Immunological Classification of Leukemias
criteria, lineage scores were 3.5 (T) and 3 (B), consistent with biphenotypic leukemia.
MPAL has inferior survival compared with lineage-defined ALL and remains
therapeutically challenging due to uncertainty in optimal induction strategy. Emerging
data support ALL-directed regimens with risk-adapted consolidation, underscoring
that precise immunophenotypic classification informs treatment algorithms and risk
stratification. Misclassification as isolated T-ALL or B-ALL may lead to inappropriate
therapy and poorer outcomes.
Conclusion
To our knowledge, this is the first reported Filipino pediatric MPALB/T case, emphasizing the need for comprehensive immunophenotyping and local
molecular and outcome data to guide evidence-based management.
Leukemia, Biphenotypic, Acute
;
Phenotype
;
T-Lymphocytes
2.The IL-23p19 monoclonal antibody significantly alleviates nephritis in MRL/lpr lupus mice by modulating the Th17/Treg balance.
Wei CHENG ; Saizhe SONG ; Yu SHEN ; Cuiping LIU ; Xin CHANG ; Jian WU
Chinese Journal of Cellular and Molecular Immunology 2025;41(7):620-628
Objective To investigate the therapeutic effects of interleukin 23p19(IL-23p19) monoclonal antibody in the MRL/lpr lupus-like mouse model. Methods A total of 36 female MRL/lpr mice aged 8 weeks were randomly divided into 6 groups: PBS group (blank control), IgG group (isotype IgG), dexamethasone (DEX) group (positive control), and three IL-23p19 monoclonal antibody treatment groups with different dose gradients: low dose (LD, 1 mg/kg), medium dose (MD, 3 mg/kg), and high dose (HD, 10 mg/kg). Drug intervention began at 12 weeks of age via tail vein injection. Urine protein levels were measured using urine protein test strips; serum anti-dsDNA antibody levels were detected by ELISA; serum creatinine and blood urea nitrogen levels were measured using an automatic biochemical analyzer; renal histopathological changes were analyzed by H&E and PAS staining; immunofluorescence was used to assess IgG and C3 immune complex deposition in kidney tissues; flow cytometry was employed to examine the expression of T helper 1(Th1), Th2, Th17, T follicular helper (Tfh), and regulatory T cells(Treg) cell subsets in the spleen; and RT-qPCR was used to detect the expression of related transcription factors in the spleen. Results IL-23p19 monoclonal antibody reduced urine protein levels, alleviated splenomegaly, improved renal function, and decreased anti-dsDNA antibody levels in MRL/lpr mice. It also mitigated glomerulonephritis and reduced renal immune complex deposition. Furthermore, IL-23p19 monoclonal antibody significantly suppressed the proportion of Th1 and Th17 cells while upregulating Treg cell proportion in the spleen. Additionally, it downregulated T-bet and retinoic acid receptor-related orphan receptor γt (RORγt) mRNA levels and upregulated forkhead box P3(FOXP3) mRNA levels in the spleen. Conclusions IL-23p19 monoclonal antibody demonstrates significant therapeutic effects in MRL/lpr mice, likely through modulation of the Th17/Treg cell balance.
Animals
;
Female
;
Mice, Inbred MRL lpr
;
T-Lymphocytes, Regulatory/drug effects*
;
Th17 Cells/drug effects*
;
Antibodies, Monoclonal/therapeutic use*
;
Interleukin-23 Subunit p19/immunology*
;
Mice
;
Lupus Nephritis/drug therapy*
;
Kidney/drug effects*
;
Antibodies, Antinuclear/blood*
3.The regulatory function of elevated interleukin 36γ to CD8+ T cell function in secondary fungal pneumonia patients with chronic obstructive pulmonary diseases.
Xiaoshan CUI ; Yinglan LI ; Tongxiu ZHAO
Chinese Journal of Cellular and Molecular Immunology 2025;41(7):637-643
Objectives To investigate interleukin 36γ (IL-36γ) expression, and analyze the influence of IL-36γ to CD8+ T cell activity in chronic obstructive pulmonary diseases (COPD) patients with secondary fungal pneumonia. Methods Peripheral blood was collected from 47 COPD patients, 39 COPD patients with secondary fungal pneumonia, and 20 controls. Bronchial alveolar lavage fluid (BALF) was isolated from 27 COPD patients with secondary fungal pneumonia. CD8+ T cells were purified. The levels of four IL-36 isoforms in plasma and BALF were measured by enzyme linked immunosorbent assay (ELISA). CD8+ T cells were stimulated with recombinant human IL-36γ. The levels of interferon γ(IFN-γ), tumor necrosis factor α(TNF-α), perforin and granzyme B in the cultured supernatants were measured by ELISA. Recombinant human IL-36γ-stimulated CD8+ T cells were co-cultured with NCI-H1882 cells in either direct cell-to-cell contact or TranswellTM manner. The levels of IFN-γ, TNF-α, and lactate dehydrogenase in the cultured supernatants were assessed. The percentage of target cell death was calculated. Results Plasma IL-36α, IL-36β, and IL-36γ levels were significantly elevated in both COPD group and COPD with secondary fungal pneumonia group compared with those in control group. However, only plasma IL-36γ level was higher in COPD with secondary fungal pneumonia group than that in COPD group [(200.11±99.95)pg/mL vs (53.03±87.18)pg/mL, P=0.023]. There was no remarkable difference in plasma IL-36 receptor antagonist level among three groups. IL-36γ level in BALF from infectious site was higher than that from non-infectious site in COPD with secondary fungal pneumonia group [(305.82±59.60)pg/mL vs (251.93±76.01)pg/mL, P=0.011]. IL-36γ stimulation enhanced IFN-γ, TNF-α, perforin and granzyme B secreted by CD8+ T cells. When IL-36γ-stimulated CD8+ T cells were directly mixed with NCI-H1882 cells for co-culture, the percentage of cell death was increased [(16.06±3.67)% vs (11.47±2.36)%, P=0.002]. When using TranswellTM plate for non-contact co-culture, IL-36γ-stimulated CD8+ T cell-mediated death of NCI-H1882 cells showed no significant difference compared to that without stimulation [(4.77±0.78)% vs (4.99±0.92)%, P=0.554]. Conclusion IL-36γ level in plasma and infectious site is elevated in COPD patients with secondary fungal pneumonia, which enhances the cytotoxicity of CD8+ T cells in peripheral blood and infectious microenviroment.
Humans
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Pulmonary Disease, Chronic Obstructive/complications*
;
CD8-Positive T-Lymphocytes/metabolism*
;
Male
;
Female
;
Aged
;
Middle Aged
;
Interferon-gamma/metabolism*
;
Interleukin-1/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Lung Diseases, Fungal/complications*
;
Bronchoalveolar Lavage Fluid/chemistry*
;
Perforin/metabolism*
;
Pneumonia/immunology*
;
Granzymes/metabolism*
4.Effect of type 2 innate lymphocytes on Treg and CD8+ T cell function through IL-9 in chronic lymphocytic leukemia.
Ruixue YANG ; Xuejiao ZENG ; Jianhua QU
Chinese Journal of Cellular and Molecular Immunology 2025;41(8):673-679
Objective To investigate the differences of type 2 innate lymphocytes (ILC2) and interlukin 9 (IL-9) between chronic lymphocytic leukemia (CLL) patients and healthy controls, and to understand the effects of ILC2 on the function of regulatory T cells (Tregs), CD8+ T cells and CLL cells through IL-9. Methods Flow cytometry was used to detect the levels of ILC2 and Tregs in the peripheral blood of 45 newly diagnosed CLL patients and 24 healthy controls, and the expressions of granzyme B and perforin in CD8+ T cells in the peripheral blood of 28 patients and 15 healthy controls; ELISA was used to detect the level of IL-9 in the serum. ILC2 of patients and healthy controls was sorted by immunomagnetic beads and cultured separately, and the level of IL-9 in the culture supernatant was measured by ELISA. ILC2 sorted from CLL patients and healthy control-derived peripheral blood mononuclear cells(PBMCs) were co-cultured with the B cell leukemia MEC-1 cells, one group was supplemented with IL-9 antibody and the other group was not. After 72 hours of culture, the ratio of Tregs, programmed death 1 (PD-1), T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), cytotoxic T lymphocyte antigen 4 (CTLA-4) on Tregs, granzyme B and perforin in CD8+ T cells were measured by flow cytometry, IL-9 level of the culture supernatant was measured by ELISA, the apoptosis of MEC-1 cells was measured by Annexin V-PI. Results Compared with the healthy control group, the levels of ILC2, Tregs and IL-9 in the CLL group increased significantly. The levels of granzyme B and perforin in CD8+ T cells were positively correlated in the peripheral blood of CLL patients. Compared with the healthy control group, IL-9 levels in the supernatant of sorted ILC2 from CLL patients increased. In the anti-IL9 antibody group, the level of PD-1 and TIGIT on Tregs decreased, and the level of granzyme B in CD8+ T cells increased significantly. The level of IL-9 in the anti-IL9 antibody group decreased statistically. And MEC-1 cells showed increased early apoptotic rate in the anti-IL9 antibody group statistically. Conclusion In CLL, ILC2 affects CD8+ T cells and Tregs through IL-9, which weakens the anti-tumor effect of CD8+ T cells, enhances the immunosuppressive effect of Tregs, and plays a role in the occurrence and development of CLL disease.
Humans
;
Leukemia, Lymphocytic, Chronic, B-Cell/immunology*
;
CD8-Positive T-Lymphocytes/immunology*
;
T-Lymphocytes, Regulatory/immunology*
;
Middle Aged
;
Male
;
Female
;
Interleukin-9/blood*
;
Aged
;
Granzymes/metabolism*
;
Perforin/metabolism*
;
Immunity, Innate
;
Adult
;
Lymphocytes/immunology*
5.The important role and interaction of platelet-activating factor and T cell immune function in the pathogenesis of vitiligo.
Yi LIU ; Xiaoping LI ; Yao CHEN
Chinese Journal of Cellular and Molecular Immunology 2025;41(8):717-723
Objective To investigate the relationship between serum platelet-activating factor (PAF) level, T cell immune function and disease activity in vitiligo patients. Methods A total of 102 patients with vitiligo treated in our hospital from July 18th, 2022 to July 26th, 2023 were enrolled as study subjects. According to VIDA score, the patients were divided into an advanced-stage group (n=54) and a stable stage group (n=49). PAF and T lymphocyte levels were compared between the two groups. Logistic regression analysis was performed to examine the relationship between PAF levels and disease activity, as well as their correlation with T cell subsets. Unconditional logistic regression modeling was employed to analyze the interaction between PAF levels and T cell subsets in disease activity. Results No significant difference was observed in CD3+ levels between advanced and stable stage vitiligo patients. PAF and CD8+ levels in advanced group were significantly higher than those in stable group, while CD4+ levles and CD4+/CD8+ ratios were significantly lower than those in stable group. When PAF level was 18.24 ng/L, the maximum Youden index reached 0.670, with corresponding sensitivity of 84.22% and specificity of 82.77%. The area under ROC curve AUC was 0.858. The intensity of association between PAF level and disease activity was nonlinear dose-response relationship. Among patients with VIDA score ≥1, significant differences were observed in both CD4+ and CD8+ levels across different PAF levels, and the CD4+/CD8+ ratios in vitiligo patients with different VIDA scores was significantly different. Interaction analysis revealed that after adjusting for confounding factors, the effect of PAF levels and T cell subsets on disease activity in vitiligo patients showed significant interaction in both additive model (RERI=4.674, 95%CI: 1.032~11.942; AP=0.763, 95%CI: 0.336~1.201; S=6.854, 95%CI: 1.904~16.520) and multiplicative model (OR=3.461, 95%CI: 1.365~8.713). Conclusion Serum PAF, CD4+, CD8+ and CD4+/CD8+ of vitiligo patients are closely related to disease activity, and PAF level interacts with T cell subsets (CD4+, CD8+, CD4+/CD8+) in the disease activity of vitiligo patients. PAF and T cell immune function may contribute to the occurrence and development of vitiligo, which could serve as clinical indicators of disease activity to guide timely management.
Humans
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Vitiligo/blood*
;
Platelet Activating Factor/immunology*
;
Male
;
Female
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Adult
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Middle Aged
;
Young Adult
;
T-Lymphocytes/immunology*
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Adolescent
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T-Lymphocyte Subsets/immunology*
6.Preparation and application of CD318 monoclonal antibody.
Ke CHAO ; Ziyang WANG ; Jie ZHAO ; Meijia YANG
Chinese Journal of Cellular and Molecular Immunology 2025;41(9):818-826
Objective To prepare CD318-specific monoclonal antibodies and evaluate their specificity, affinity, and application in immunological detection, laying the foundation for the development of CD318-targeted antibody drugs. MethodsCD318 protein was expressed and purified, and was used as an antigen to immunize mice, then mice with higher antiserum titers were screened. We prepared CD318-specific monoclonal antibodies through cell fusion and monoclonal screening, and the specificity, affinity, and application of the obtained monoclonal antibodies in immunological assays were evaluated. Then we constructed a CD318/CD3-targeting bispecific antibody and assessed its impact on T-cell cytotoxicity. Results Thirteen monoclonal antibodies were successfully generated, with the hybridoma clone 13-8-G2 exhibiting the highest titer, strongest specificity, and broadest applicability. The antibody was identified as an IgG1 isotype with a kappa light chain. The variable region of the light chain measured 318 bp, while the heavy chain variable region was 357 bp, yielding an affinity constant of approximately 7.68×109. The specificity of CD318 was confirmed using flow cytometry and immunofluorescence assays. Additionally, a CD318/CD3-targeting bispecific antibody was constructed using the variable regions of this CD318 monoclonal antibody, which demonstrated enhanced T-cell cytotoxicity. Conclusion High-affinity and highly specific CD318 monoclonal antibodies were successfully prepared, laying a foundation for the development of therapeutic antibodies targeting CD318.
Animals
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Antibodies, Monoclonal/biosynthesis*
;
Mice
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Antibodies, Bispecific/immunology*
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Humans
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Mice, Inbred BALB C
;
Antibody Specificity/immunology*
;
CD3 Complex/immunology*
;
Antigens, CD/genetics*
;
T-Lymphocytes/immunology*
;
Hybridomas/immunology*
;
Female
7.The role of CD8+ regulatory T cell in the pathogenesis of rheumatoid arthritis.
Lichun BAI ; Hongbin LI ; Jing WANG
Chinese Journal of Cellular and Molecular Immunology 2025;41(9):851-857
Rheumatoid arthritis (RA) is an autoimmune disease characterized by complex pathogenesis, with its development closely linked to immune dysregulation. Regulatory T cells (Tregs), as specialized immunomodulatory cells, play a pivotal role in negatively regulating immune responses and maintaining autoimmune tolerance. In recent years, extensive research has focused on the relationship between Tregs and RA pathogenesis, with the functional role of CD8+ Tregs as a critical area of investigation. This review summarizes the alterations in CD8+ Tregs during RA progression and their potential mechanisms of action. By elucidating the diversity of CD8+ Treg subsets and their intricate roles in modulating immune responses, this analysis provides novel insights and therapeutic strategies for RA diagnosis and treatment.
Arthritis, Rheumatoid/pathology*
;
Humans
;
T-Lymphocytes, Regulatory/immunology*
;
CD8-Positive T-Lymphocytes/immunology*
;
Animals
8.The effect of CD33+MDSC-mediated T lymphocyte function on the therapeutic efficacy of 125I particle implantation combined with arterial chemoembolization in the treatment of cervical cancer.
Yongjin HU ; Zanhong WANG ; Feng'e LI ; Weihong FENG ; Yupeng WANG
Chinese Journal of Cellular and Molecular Immunology 2025;41(10):905-912
Objective To explore the expression levels of CD33+ myeloid-derived suppressor cell (MDSC)-mediated T lymphocyte function and related inflammatory factors secreted by T lymphocyte subsets in patients with cervical cancer, and to analyze their correlation with the treatment efficacy of 125I particle implantation combined with arterial chemoembolization, as well as predictive value for treatment outcomes and interaction effects. Methods From January 1st, 2021 to January 1st, 2024, our hospital admitted 152 patients with advanced cervical cancer, who were confirmed by pathological examination. All patients received uterine artery chemoembolization combined with 125I particle implantation. The predictive value of CD33+MDSC levels for clinical treatment response in cervical cancer was assessed using receiver operating characteristic (ROC) curve analysis. Multivariate logistic regression analysis was performed to evaluate both multiplicative and additive interactions between CD33+MDSC and T lymphocytes in predicting clinical treatment failure of cervical cancer. Kaplan Meier method was used to analyze the survival differences between cervical cancer patients with high and low CD33+MDSC expression levels. Results Compared with the effective group, patients in the ineffective group had decreased expression levels of CD3+ T lymphocyte, CD4+ T lymphocyte, interleukin 2 (IL-2) and interferon γ (IFN-γ), while showing increased expression levels of CD33+MDSC, CD8+ T lymphocyte, IL-4 and IL-6, along with increased tumor necrosis factor α (TNF-α) levels, larger maximum tumor diameters, and a higher incidence of lymph node metastasis. The expression levels of CD33+MDSCs demonstrated good predictive performance for treatment efficacy in cervical cancer patients. The high CD33+MDSC expression group had a significantly shorter overall survival (OS) than the low CD33+MDSC expression group (6.0±1.0 months vs. 12.0±1.2 months; t=33.280). The interaction analysis revealed that CD33+MDSCs and CD8+ T lymphocytes were highly expressed, while CD3+ and CD4+ T lymphocytes were lowly expressed, which was associated with an increased risk of clinical treatment failure in cervical cancer patients. Conclusion CD33+MDSCs can inhibit CD3+ and CD4+ T lymphocytes. It can upregulate the expression of CD8+ T lymphocytes, form an immunosuppressive microenvironment, and reduce the treatment response rate of 125I particle implantation combined with arterial chemoembolization. CD33+MDSCs may serve as an independent biomarker for predicting the therapeutic efficacy and poor prognosis.
Humans
;
Female
;
Uterine Cervical Neoplasms/immunology*
;
Middle Aged
;
Chemoembolization, Therapeutic/methods*
;
Sialic Acid Binding Ig-like Lectin 3/immunology*
;
Adult
;
T-Lymphocytes/immunology*
;
Aged
;
Treatment Outcome
9.Preparation and identification of a novel microparticle-loaded DC vaccine against hepatocellular carcinoma.
Zhao ZHAN ; Xuezheng LIU ; Doudou DONG ; Dingyu CHEN ; Yaling SUN
Chinese Journal of Cellular and Molecular Immunology 2025;41(10):913-920
Objective To characterize the properties of Hepa1-6-derived microparticles (Hepa1-6-MPs), investigate their stimulatory effects on dendritic cells (DCs) and their cellular uptake pathways, and explore the specific cytotoxic effects of CD8+ T cells induced by Hepa1-6-MP-loaded DCs on hepatoma cell lines, with the aim of developing a novel immunotherapeutic model for hepatocellular carcinoma (HCC). Methods The isolated Hepa1-6-MPs were identified using Western blotting, transmission electron microscopy (TEM) and dynamic light scattering (DLS). Flow cytometry was used to assess the uptake pathways of Hepa1-6-MPs by DCs. Subsequently, enzyme-linked immunosorbent assay (ELISA) was used to measure the effects of Hepa1-6-MP-loaded DCs on the release levels of tumor necrosis factor α(TNF-α) and interferon γ(IFN-γ) into the supernatant of CD8+ T cells. Lactate dehydrogenase (LDH) tests were conducted to evaluate the cytotoxic effects of CD8+ T cells stimulated by Hepa1-6-MP-loaded DCs on hepatoma cells. Results The morphology, size and protein markers of Hepa1-6-MPs met the established criteria. Hepa1-6-MPs enhanced the expression of DC maturation markers CD80 and CD86, and were internalized by DCs via clathrin-mediated endocytosis and phagocytosis pathways. Subsequently, Hepa1-6-MP-loaded DCs stimulated CD8+ T cells to release high levels of TNF-α and IFN-γ, which induced their specific cytotoxicity against HCC cells. Conclusion These findings suggest that Hepa1-6-MP-loaded DCs may be a promising HCC immunotherapeutic tool.
Carcinoma, Hepatocellular/therapy*
;
Liver Neoplasms/therapy*
;
Dendritic Cells/immunology*
;
Humans
;
Cancer Vaccines/immunology*
;
CD8-Positive T-Lymphocytes/immunology*
;
Cell Line, Tumor
;
Tumor Necrosis Factor-alpha/immunology*
;
Interferon-gamma/immunology*
;
Cell-Derived Microparticles/immunology*
;
Animals
10.She-Ti-Zhi-Qiu decoction ameliorates allergic rhinitis in rats by regulating the gut microbiota and Th17/Treg balance.
Chao LUO ; Lisha LIU ; Yajing HUANG ; Shaobo LIU ; Shunlin PENG
Chinese Journal of Cellular and Molecular Immunology 2025;41(11):961-970
Objective To explore the mechanism by which She-Ti-Zhi-Qiu decoction alleviates allergic rhinitis (AR) through gut microbiota-mediated regulation of T helper cell 17(Th17)/regulatory T cells(Treg) balance and related cytokines. Methods Twenty-eight female SD rats were randomly divided into four groups: the Control group, Model group, STZQ group, and Probiotics group. Except for the Control group, all other groups were sensitized with ovalbumin (OVA) to establish AR models. The Control and Model groups received intragastric administration of normal saline, while the STZQ group was administered She-Ti-Zhi-Qiu Decoction, and Probiotics group received probiotics. After two weeks of continuous intragastric administration, nasal mucosa, serum, peripheral blood, and colon contents were collected. The inflammation of nasal mucosal tissue was assessed via HE staining. 16S rDNA sequencing was used to detect and analyze the structure and content of bacteria in colon contents. Flow cytometry was used to detect the relative proportions of Treg and Th17 cells in peripheral blood. ELISA was used to measure the levels of Th17- and Treg-related cytokines in serum. Results Compared with the Control group, the Model group showed an inflammatory response in nasal mucosal tissue, along with increased IL-17A and IL-17E levels and decreased IL-10 levels. The percentage of Th17 cells in peripheral blood increased, while the percentage of Treg cells decreased. Beneficial bacteria in the intestine were decreased, while pathogenic bacteria were increased. Compared with the Model group, the STZQ group showed lower serum IL-17A and IL-17E levels and higher IL-10 levels. The percentage of Th17 in peripheral blood decreased, while the percentage of Treg increased. There was an increase in beneficial bacteria in the intestine and a decrease in pathogenic bacteria. The changes in the microbiota were correlated with IL-17A, IL-17E, and IL-10 levels. Conclusion She-Ti-Zhi-Qiu decoction can ameliorate the inflammation of AR by regulating gut microbiota and Th17/Treg immune balance.
Animals
;
T-Lymphocytes, Regulatory/drug effects*
;
Th17 Cells/drug effects*
;
Gastrointestinal Microbiome/drug effects*
;
Rats, Sprague-Dawley
;
Drugs, Chinese Herbal/therapeutic use*
;
Female
;
Rhinitis, Allergic/microbiology*
;
Rats
;
Cytokines

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