[Study on T-lymphocyte culture and function of T-lymphocyte subsets in patients with aplastic anemia]

T-lymphocytes form the peripheral blood of 12 patients with aplastic anemia (AA) and 4 patients with aplastic anaemia-paroxysmal hemoglobinuria syndrome (AA-PNH) were cultivated and their subsets were measured by monoclonal antibodies CD4, CD8, CD25 with indirect immunofluorescence technique. Change of the proportion of T-lymphocyte subsets was observed in 5 patients with AA after the mononuclear cells were activated with phytohemagglutinin (PHA). Its was shown that the number of CFU-T of the patients with AA was apparently decreased in comparison with that of normal controls (P less than 0.05). Disorder of T-lymphocyte subsets took place in patients with AA. The percentages of CD8 and CD25 lymphocytes were increased. The helper: suppressor T-lymphocytes (CD4:CD8) ratio was significantly increased (P less than 0.01). In the cases of AA-PNH, the number of CFU-T was significantly increased (P less than 0.01) and that of T-lymphocyte subsets did not change. The ratio of CD4/CD8 in 5 patients with AA was further decreased after activating mononuclear cells with PHA. These results showed that the increase of T-lymphocytes in patients with AA may account for the low level of CFU-T; the high level of CFU-T in patients with AA-PNH may be related to the multiplication of bone marrow cells. However, there may be a potential disorder of immune system on patients with AA at the same time.