RELEASE OF LT MOLECULES WITH RESTRICTED PHYSICAL HETEROGENEITY BY A CONTINUOUS HUMAN LYMPHOID-CELL LINE INVITRO

Lymphotoxins released by lectin activated human lymphoid cells in vitro are complex and can be resolved by molecular sieving techniques into multiple classes of activity, termed complex, α,β and γ. The classes can be further resolved into sub-classes on the basis of their charge by ion-exchange chromatography and electrophoresis. We found the lytic activity spontaneously released by the continuous human B lymphoid cell line, PGLC-33H, to be of limited physical heterogeneity, and essentially identical to the α mol. wt class of human LT† molecules. This was determined by functional, physcial-chemical and immunologic means. We found that most of the α-LT charge sub-classes present in supernatants from mitogen stimulated normal lymphocyte cultures were also detected in these supernatants. These studies suggest: (a) this cell line provides a source of human LT for study with restricted heterogeneity; (b) different lymphoid cells (T and B) may be capable of releasing different LT molecules; and (c) use of selected human lymphoid cell lines may be useful to examine the biokinetics of LT synthesis and release. © 1979.