Analysis on Cellular Immune Function Recovery after HLA Mismatched Allogeneic Hematopoietic Stem Cell Micro-Transp- lantation in Elderly AML Patients

Abstract

To investigate the recovery of cellular immunity in elderly patients with acute myeloid leukemia (AML) after micro-transplantation (MST) and the changes of cellular immunity during relapse, as well as their clinical significance. A total of 41 elderly AML patients who received MST treatment in a single center and 25 healthy elderly people were included. Immune function among different age groups in normal population was compared. Furthermore, immune fuction was compared between elderly AML patients of different age groups who achieved continuous complete remission (CR) after MST treatment and normal controls, between high risk group and medium-low risk group, as well as among before diagnosis, after CR, and relapse. Peripheral blood of patients and normal controls was collected, and the percentage of lymphocyte subsets was detected by multi-color flow cytometry. Thirty-five patients achieved CR after MST treatment while six patients did not. After MST treatment, CD3+ T cells, CD8+T cells and activated T cells in all age groups were higher than normal. Significant recovery of CD3+ and CD8+T cells was observed in both high risk and medium-low risk groups, and the overall recovery of immune cells in medium-low risk group was better. It was also observed that B lymphocytes and NK cells could not return to normal levels within 1 year after MST treatment. The proportion of CD3+ T cells, CD4+ T cells, and CD4/CD8 ratio were significantly decreased during relapse compared with continuous CR after MST (P<0.05). MST treatment can promote the recovery of CD3+T cells, CD8+T cells and other killer cells, so as to improve the cellular immune function of elderly patients, which provides a new immune cell therapy for elderly AML.