Studies of human T gamma cells: division of a T gamma subset in normal and leukemic cells by using anti-T gamma-CLL heteroantiserum.

A specific heteroantiserum was prepared against the leukemic cells from a patient with T-derived chronic lymphocytic leukemia (T-CLL). The anti-serum was absorbed with cells of a morphologically different type from another patient with T-CLL. Both the immunizing cells and absorbing cells had Fc receptor for IgG (Fc gamma R), so the former case was named T gamma-CLL type 1, and the latter T gamma-CLL type 2. This antiserum, termed anti-T gamma-1, reacted with 19% of normal peripheral blood T lymphocytes, but not with non-T lymphocytes or monocytes. The T lymphocytes in the blood that reacted to anti-T gamma-1 were 72% of the T gamma cells. Anti-T gamma-1 also reacted to 60-78% of the thymocytes. Except for T gamma-CLL type 1 cells, anti-T gamma-1 did not react with various types of leukemia cells from lymphoid malignancies, myelogenous leukemias and monocytic leukemias. Studies on the relation between anti-T gamma-1 and OKT8 monoclonal antibody revealed that anti-T gamma-1 reactive (anti-T gamma-1+) cells and OKT8+ cells largely overlapped, but they were different in part. More interestingly, OKT8 inhibited Fc gamma R binding, but anti-T gamma-1 did not. These results indicate that anti-T gamma-1 is useful for detecting a certain subset of T cells and for classifying lymphoproliferative disorders.