RESUMEN
The study was aimed to investigate the changes of T-cell subgroups in the peripheral blood (PB) of patients with aplastic anemia (AA) and the relationships between these changes and the pathogenesis of AA and the immunosuppressive therapeutic effects in AA, in order to provide a basis for selecting rational therapy of AA patients. T-cell subtype and the ratio of CD4+/CD8+ cell in the PB of 88 AA patients which had been diagnosed clearly and given conventional therapy or conventional therapy combined with immunotherapy were analyzed by tri-colour fluorescence-labeled monoclonal antibody and using multiparameter flow cytometry. The patients with AA were divided into normal type of ratio, inverted type of ratio, hypernormal type of ratio according to the ratio of CD4+/CD8+ cell in normal group, and then the relations of these subtype with patients' conditions and therapeutic effects were investigated. The results showed that the percentage of normal type of ratio in all patients was 39.8%, the percentage of inverted type of ratio in all patients was 44.3%, The percentage of hypernormal type of ratio in all patients was 15.9%. In the conventional therapy alone, there was no significant difference on therapeutic effects among these three immunological subtypes. In combined immunotherapy, total therapeutic efficacy of AA patients with inverted type of ratio and AA patients with immunologic abnormality (inverted type + hypernormal type) was 84.2% and 82.6% respectively, which were more than that in conventional therapy (45.5% and 42.8%) (p < 0.05). Total therapeutic efficacy in these patients was better than that in AA patients with normal type. It is concluded that significant abnormal ratios of CD4+/CD8+ exist in the majority of AA patients, abnormal ratios of CD4+/CD8+ both may be showed as increase or decrease, immunologic abnormality may play a role in pathogenesis of the patients with AA. The detection of PB T-cell subtype in patients with aplastic anemia contributes to evaluation of patients' condition and choice of rational treatment prescription, and enhancement of diagnostic level and therapeutic efficacy significantly, which is an important indicator for therapeutic strategy also.