The Expression And Clinical Significance Of Tregs In Acute Myeloid Leukemia

Object:we test the percentages of CD4⁺CD25⁺CD127^lowTregs in peripheral blood of acute myloid leukemia(AML) patients, evaluate the proportion of CD4⁺CD25⁺CD127^low Tregs in different phases and pre/after six periods regular chemotherapy, and explain the occurrence and the turnover of AML by immunology.Materials and Methods:we select peripheral blood samples from 80 AML patients and 15 normal controls, and test the level of CD4⁺T cells and CD4⁺CD25⁺CD127^lowTregs by flow cytometry. The percentages were compared among AML patients,normal controls and the patients from different phases, in the meanwhile, we compare the percentages of which expressed between first pre-chemotherapy and after six periods regular chemotherapy in both continuous remission patients and refractory/relapse patients. After that, we analysis the correlations between the level of CD4⁺CD25⁺CD127^lowTregs and clinical characteristics.Results:(1) Compared with normal controls, the percentages of CD4⁺cell in primary treatment patients and refractory/relapse patients are significantly lower(P< 0.05). There are no significant differences between normal controls and continuous remission patients(P>0.05).(2) Compared with normal controls, the perscentages of CD4⁺ CD25⁺CD127^lowTregs in primary treatment patients and refractory /relapse patients are significantly higher (P< 0.05). There are no significant differences between normal controls and remission patients(P >0.05).(3) In different phrases, the percentages of CD4⁺CD25⁺CD127^low Tregs in primary treatment patients and refractory/relapse patients are both higher than remission patients (P<0.05). There are no differences between primary treatment patients and refractory/relapse patients.(4) After six periods regular chemotherapy, when patients reached continuous complete remission, the percentages of CD4⁺cell and CD4⁺CD25⁺CD127^low Tregs are significantly different from their first pre-chemotherapy(P< 0.05), but there are no differences between refractory/relapse patients and their first pre-chemotherapy(P>0.05).(5) The percentages of CD4⁺CD25⁺CD127^low Tregs in AML patients were uncorrelated with their clinical characteristics.Conclusion:(1) The percentages of CD4⁺T cell and CD4⁺CD25⁺CD127^lowTregs in primary treatment AML patients are abnormal, but when the patients reached complete remission, the level of which return to normal, it indicate that there are immune-disorder in AML patients.(2)The percentages of CD4⁺CD25⁺CD127^low Tregs in refractory/ relapse patients did not return to normal, which indicate that it correlate with disease phrase。(3)There are no correlations between the percentages of CD4⁺ CD25⁺CD127^low Tregs in primary treatment patients and their clinical characteristics, which indicate that maybe Tregs is an independent pathogenetic and prognostic factor.