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Peripheral CD4+ T Cells (peripheral + cd4+_t_cell)
Selected AbstractsPhenotypic and genetic analyses of T-cell-mediated immunoregulation in patients with Type 1 diabetesDIABETIC MEDICINE, Issue 10 2006Y. Tsutsumi Abstract Aims To investigate the contribution of regulatory T cells and co-stimulatory molecules in CD4+ T cells to the development of Type 1 diabetes (T1D). Methods Twelve patients with T1D, nine patients with systemic lupus erythematosus (SLE), and 12 age-matched healthy control subjects participated. We analysed the proportions of CD25+CD4+ T cells and natural killer T cells (NKT cells), and the expression levels of Foxp3, CTLA-4, CD28, ICOS, PD-1 and BTLA in peripheral blood mononuclear cells and purified CD4+ T cells. Results There were no significant differences in the proportions of CD25+ CD4+ T cells or NKT cells among the three groups. PD-1 expression levels of peripheral CD4+ T cells from T1D patients were significantly lower than those from healthy control subjects (P = 0.00066). In contrast, PD-1 expression levels were similar in SLE patients and healthy control subjects. The expression levels of Foxp3, CTLA-4, CD28, ICOS and BTLA were similar in the three groups. Conclusions Decreased expression of the PD-1 gene in CD4+ T cells may contribute to the development and/or maintenance of autoimmune T1D. As the population studied was small and heterogeneous, further studies are required to confirm the findings. [source] Human papillomavirus infection and cervical abnormalities in Nairobi, Kenya, an area with a high prevalence of human immunodeficiency virus infectionJOURNAL OF MEDICAL VIROLOGY, Issue 5 2008Rika Yamada Abstract Human papillomavirus (HPV) infection and cervical abnormalities, and their association with human immunodeficiency virus (HIV) infection were studied in 488 women who visited a health center in Nairobi. PCR-based HPV and cervical cytology tests were carried out on all participants, and peripheral CD4+ T cells and plasma HIV RNA were quantitated in HIV positive women. HIV were positive in 32% (155/488) of the women; 77% of these were untreated, and the others had been treated with anti-retroviral drugs within 6 months. Cervical HPV infection was detected in 17% of HIV negative and 49% of HIV positive women. Low-grade squamous intraepithelial lesions were observed in 6.9% of HIV negative and 21% of HIV positive women, while high-grade squamous intraepithelial lesions and cancer were seen in 0.6% and 5.8%, respectively. Multivariate analysis revealed that HIV and HPV infections were associated with each other. Cervical lesions were significantly associated with high-risk HPVs and with HIV infection, depending on HPV infection. HPV infection increased in accordance with lower CD4+ T cell counts and higher HIV RNA levels, and high-grade lesions were strongly associated with high-risk HPV infection and low CD4+ T cell counts. Immunosuppression as a result of HIV infection appears to be important for malignant progression in the cervix. Nationwide prevention of HIV infection and cervical cancer screening are necessary for the health of women in this area. High-risk HPV infection and low CD4+ T cell counts are the risk factors for cervical cancer. J. Med. Virol. 80:847,855, 2008. © 2008 Wiley-Liss, Inc. [source] ORIGINAL ARTICLE: TH1 , TH2 Response and the Atopy Risk in Patients with Reproduction FailureAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2009Jana Hanzlikova Problem, Enhanced TH2 activity is characteristic for atopic diseases and is observed also in physiological pregnancy. The immune causes of repeated pregnancy losses and/or repeated in vitro fertilization failure may be associated with TH2 hypoactivity. The association with frequency of atopic diseases is unclear. Method of Study, Intracellular production of IL-4 and IFN-, by peripheral CD4+ T lymphocytes was studied, as well as serum levels of total and allergen specific IgE. Simultaneously skin prick tests with inhalant allergens were performed, and clinical features of atopy were registered by means of a questionnaire. Results, Lower intracellular production of IL-4 by peripheral CD4+ T cells and lower frequency of elevated total and allergen specific IgE were found in women with reproduction failure compared to controls, as well as lower frequency of some symptoms possibly associated with atopy. Conclusion, Our study showed the presence of TH2 hypoactivity in women with reproduction failure, which may be associated with lower occurrence of atopic diseases. [source] A Possible Role of CD4+CD25+ T Cells as Well as Transcription Factor Foxp3 in the Dysregulation of Allergic RhinitisTHE LARYNGOSCOPE, Issue 5 2007Geng Xu MD Abstract Background: Allergic rhinitis (AR) is a Th2 predominant disease, and its pathogenic mechanism is still poorly understood. CD4+CD25+ T cells account for approximately 5% to 10% peripheral CD4+ T cells and has been shown to regulate the activation of effector T cells in the periphery. The activity of CD4+CD25+ T cells is associated with the transcription factor Foxp3. The present study aimed to evaluate the possible role of CD4+CD25+ T cells as well as Foxp3 in the pathogenesis of AR. Methods: Nasal tissues and peripheral blood mononuclear cells (PBMCs) were obtained from 17 patients with AR and 11 control subjects. Foxp3 was detected in nasal tissues by immunohistochemistry and real-time reverse transcription-polymerase chain reaction (RT-PCR). CD4+CD25+ T cells and Foxp3 were evaluated in PBMCs by using flow cytometry. Concentrations of interleukin-2 (IL-2) and interferon-, (IFN-,) were measured by enzyme-linked immunosorbent assay (ELISA) in cultured PBMCs in the presence or absence of stimulation with phorbol ester (PMA) and Ionomycin. Results: The numbers of Foxp3+ cells was 129.5 ± 35.6 and 44.2 ± 20.5 cells/mm2 in nasal mucosa of two groups (P < .05). There were less Foxp3+ lymphocytes and decreased Foxp3 mRNA in AR compared with the control (P < .05). The frequencies of the CD4+CD25+ population in PBMCs of two groups were 1.99 ± 0.95% and 3.55 ± 1.27% (P < .05). There was significant difference in the frequencies of the Foxp3+CD4+ CD25+ population (1.81 ± 0.77 vs 3.37 ± 1.04, P < .05) and mean fluorescence intensity (MFI) of Foxp3 (5.93 ± 2.64 vs 11.72 ± 4.29, P < .05) in PBMCs of two groups. After stimulation, the concentrations of IL-2 and IFN-, were 182.72 ± 85.11 pg/mL and 348.94 ± 151.88 pg/mL in PBMCs with AR, while those were 90.6 ± 61.5 pg/mL and 155.64 ± 68.33 pg/mL in controls (P < .05). Conclusion: Our results indicate that CD4+ CD25+ regulatory T cells as well as Foxp3 may play a crucial role in immunological imbalance of AR. These findings suggest that increasing Foxp3 and CD4+CD25+ T cells have the potential to be new therapeutic targets for the treatment of AR. [source] | ||||||||||