The Relationshighp Of CD4~+CD25~+ Regulatory T Cells And Aplastic Anemia

Objective To identify the relationship between CD4⁺CD25⁺ regulatory T cell (CD4⁺CD25⁺Treg) and aplastic anemia(AA) and explore the significance of CD4⁺CD25⁺Treg in the process of aplastic anemia;To establish best laboratory indicators which can reflect the immune status of aplastic anemia patients;To study the conditions for the application of immunosuppressants in patients with aplastic anemia preliminary.Methods There were 25 newly diagnosed AA patients ,14 patients with effective immunosuppressive therapy , 10 patients with ineffective treatment . The newly diagnosed AA patients were further divided into severe aplastic anemia group (SAA group) and chronic aplastic anemia group (CAA group). 25 healthy volunteers from were conduct as normal control group. Three color monoclonal antibodies directly labeled with immunofluorescence were used to analyze the surface and cytoplasma antigens ,such as CD4, CD25, FoxP3 ,CD3,CD8 and so on, we used multi-parameter flow cytometry to investigate peripheral blood CD4⁺CD25⁺Treg cells and T cell subsets in AA patients . CD4⁺ cells were set as door , we analyze CD4⁺CD25⁺Treg cells of AA patients by Cell Quest Pro software. CD4⁺CD25high, CD4⁺CD25⁺Foxp3⁺ and CD4⁺CD25⁺CD127low indicators were marked Treg cell, CD4⁺CD25⁺CD127high indicators was marked the active CD4⁺ effect T cell . All data was analyzed by statistical software SPSS13.0; the measurement data was expressed as mean±standard deviation ( x±s). We used t test when two sets of values in line with normal distribution and homogeneity of variance, or using non-parametric test; we used analysis of variance when multiple sets of comparisons between values in line with normal distribution and homogeneity of variance, or we used non-parametric tests,P<0.05 meant the difference was statistically significant.We used paired chi-square test to compare differences in detection methods, P <0.05 meant the difference was statistically significant.Results(1) CD4⁺CD25^highT,CD4⁺CD25⁺FoxP3⁺T, CD4⁺CD25⁺CDl27^low T cells accounted for the proportion of CD4⁺cells of SAA group and CAA group were both lower than the control group(0.791±0.309%,1.087±0.492%,3.225±1.092%),(1.125±0.192%,1.712±0.293%,4.034±0.602%),(1.734±0.247%,2.661±0.334%,5.334±0.942%); however, the above-mentioned three indicators of SAA group was significantly lower than CAA group ,the ineffective treatment group was lower than the effective treatment group(0.885±0.461%,1.834±0.582%,3.702±1.207%),(1.792±0.381,2.668±0.972%,5.245±1.106%) (P<0.05), normal control group and the effective treatment group had no significant (P> 0.05); peripheral blood active CD4⁺ effect T cells (CD4⁺CD25⁺CDl27^high) of SAA group and CAA group were higher than the normal control group (7.883±1.639)%,(7.553±1.881)%,(4.492±0.864)%;ineffective treatment group was higher than effective treatment group (P <0.05);the differences between SAA group and CAA group were both no statistical significance (P> 0.05 ). (2)compared with the normal control group and patients with effective treatment group,the ratio of CD4/CD8 in newly diagnosed SAA group and CAA group were inversion (P <0.05) (0.87±0.33,0.95±0.48,1.41±0.31), while the SAA group compared with CAA group , ineffective treatment group compared with effective treatment group, the ratio of treatment fails group were both no statistical significance (P> 0.05 ) (3) The positive rates of and T cell subsets and CD4⁺CD25⁺Treg cells to monitor the immune status of AA in patients with abnormal were 72% and 60%, the former is more sensitive than the latter (P <0.05) .Conclusion (1) Compared with healthy adults, the level of CD4⁺CD25 ⁺T regulatory cells in majority of AA patients significantly decreased,Treg cells may be play aimportant hole during the pathogenesis of AA (2) CD4⁺CD25 ⁺Treg cells in reducing the severity of AA is closely related to ; (3) Monitoring the levels of CD4⁺CD25⁺T regulatory cells should be valuable for predicting the therapeutic effect and prognosis of AA, and guiding the application of immunosuppressant. (4)One of the causes of invalidity is that CD4⁺CD25⁺Treg cell of AA patients has not been corrected some of the existing immunosuppressive therapy. (5) In addition, ex vivo expansion and recurrent infusion of autoallergic Tregs may be a new therapeutic strategies to treat AA.