T-chronic lymphocytic leukaemia presenting as primary hypogammaglobulinaemia--evidence of a proliferation of T-suppressor cells.

A 63 year old man with late onset hypogammaglobulinaemia is described. Splenectomy, carried out because of marked splenomegaly and pancytopenia, demonstrated marked T lymphocytic infiltration in the splenic red pulp with prominent germinal centres. A persistent peripheral blood and bone marrow lymphocytosis ensued (10 X 10(9)/l and 40% respectively) and this was consistent with T-chronic lymphocytic leukaemia (T-CLL). Over 88% of his blood lymphocytes were E+, OKT3+, OKT8+ and OKT11+; 54% of the T lymphocytes had receptors for IgG (T gamma cells). Functional studies showed that the T lymphocytes of this patient lacked killer and natural killer cell function but they effectively suppressed the differentiation of normal B cells in a PWM stimulated system. It is suggested that the T-CLL in this patient resulted from the proliferation of the T suppressor subset which was responsible for his hypogammaglobulinaemia.