Role of CD4(+)CD25(high+)FOXP3(+) Regulatory T Cells in Psoriasis

BACKGROUND: CD4(+)CD25(high+)regulatory T cells (Tregs) are considered to be of vital importance for maintaining immunologic self-tolerance and preventing autoimmune diseases. These cells have been found to be deficient in skin lesions and in the peripheral blood of patients with psoriasis. OBJECTIVE: To investigate the role of Tregs in the pathogenesis of psoriasis and to evaluate the changes in Tregs in relation to the severity and the clinical course of psoriasis. METHODS: Immunohistochemistry (CD3, 4, 8, 79 and FOXP3) was performed in 22 psoriatic patients compared to 5 normal controls. Flow cytometry (CD3, 4, 8, 25 and FOXP3) was performed in 18 psoriatic patients and 8 normal volunteers and reverse transcriptase polymerase chain reaction (foxp3 mRNA) was performed in 8 psoriasis patients. RESULTS: An increase in the FOXP3(+) cell fraction was detected in the lesional psoriatic skin irrespective of the severity of psoriasis as compared with the normal skin. However, a decrease in FOXP3(+) cells was observed in the samples obtained from psoriasis of 'acute course'. FOXP3(+) Treg populations in the blood of the 'acute course' psoriasis was not different compared to that of 'chronic course' psoriasis and normal controls. CONCLUSION: The deficiency of FOXP3(+) Tregs in the lesional psoriatic skin might be responsible for the exacerbation of psoriasis.

Analysis of the CD4+ CD25high regulatory T cells in peripheral blood of chronic hepatitis B virus in fected patients / 中华微生物学和免疫学杂志

Objective To analyze of CD4+ CD25high regulatory T cells(Treg)in peripheral blood of chronic HBV patients and its correlation with multiple clinical indicators.Methods Thirty-five hepatitis B virus(HBV)infected patients in this study were divided into four different clinical types:HBsAb+group(n=5),inactive hepatitis group(n=8),chronic hepatitis group(n=12),and immune tolerance group(n=10).The number of CD4+CD25high Treg and related T cells subgroup in CD3/CD4/CD8 was thoroughly examined by flow cytometry in peripheral blood of HBV infected patients and the healthy contrast group(n=12).Serum HBV markers were determined by commercial ELISA kits.Serum HBV DNA was quantified by commercial real-time PCR kit.Statistical differences were studied to investigate the correlations between CD4+CD25high Treg and different clinical types of HBV infection and clinical indicators.Results The absolute counts of CD25high Treg and its frequency in CD4+ T cells were similar between HBV infected patients [(12.35±6.48)/μ,(1.82±0.87)%]and health controls[(8.91±3.11)/μl,(1.35±0.39)%],P＞0.05.The frequency of CD25high Treg in CD4+ T cells from the immune tolerance group was significantly higher than that of the HBsAb+ group,chronic hepatitis group,and the healthy contrast group(P＜0.05).The absolute counts of CD25high Treg from the immune tolerance group were significantly higher than the healthy control group(P＜0.05),and the frequency of CD25high Treg in CD4+ T cells is negatively correlated to the ALT level(r=-0.418,P=0.038),positively correlated to CD4/CD8 ratio(r=0.344,P=0.021),no correlation to the HBV DNA level(r=0.118,P＞0.05).The absolute counts of CD25high Treg were positively correlated to CD4/CD8 ratio(r=0.360,P=0.015),no correlation to ALT level and HBV DNA level(r=-0.211,r=0.060,P＞0.05).Conclusion CD4+ CD25high Treg may play a role in immunopathogenesis of chronic HBV infection.