Abstract
A case of T-ALL with suppressor activity was reported. A 29-year-old man with a giant thymoma, remarkable leukocytosis and hypogammaglobulinemia was diagnosed acute T lymphoblastic leukemia, based on the hematological and immunological examinations. The leukemic blasts with high N/C ratio were positive for E-rosette formation, but were negative for IgG-FCR, Ia-like antigen, SmIg, TdT reaction and anti-ATLA antibodies. Furthermore, 71% and 58% of these blasts were reactive to OKT 8 and 10, respectively, showing them to be in the level of mature thymocyte.
In vitro studies showed suppressor activity of these blasts specifically on IgG synthesis by normal peripheral lymphocytes.
Clinically, the patient's hypogammaglobulinemia returned to normal level after radiochemotherapy, suggestig the suppressor activity of these blasts in vivo.
