Lymphocyte responsiveness to thymosin in angioimmunoblastic lymphadenopathy with lymphomatous transformation

Lymphocytes from a patient with angioimmunoblastic lymphadenopathy with lymphomatous degeneration were tested in vitro for thymosin responsiveness. The percentage of lymphocytes forming spontaneous (E) rosettes to sheep red blood cells (SRBC) was 37 and 32% in the absence of thymosin on two separate occasions. Lymphocytes incubated with thymosin formed rosettes in 55 and 43% when incubated with 0.1 micrograms/ml and 66 and 63% when incubated with 100 micrograms/ml, respectively. The patient subsequently received thymosin while in a preterminal condition. No clinical response to thymosin was apparent and lymphocytes tested 8 days after starting thymosin treatment demonstrated reduced thymosin responsiveness (31% without thymosin vs 37% with 100 micrograms/ml). The failure to respond clinically to thymosin treatment may be related to the preterminal condition. The in vitro responsiveness to thymosin suggests that thymosin effect should be examined earlier in the course of this disease process.