Journal of Experimental Medicine, Vol 141, 584-599, Copyright © 1975 by Rockefeller University Press
Rosette-forming ability of thymus-derived lymphocytes in cell-mediated immunity. I. Delayed hypersensitivity and in vitro cytotoxicity
BE Elliott, JS Haskill and MA Axelrad
Effector cells in delayed hypersensitivity and in vitro cytotoxicity were
studied in lymph node cells from animals immunized with sheep erythrocytes
(SRBC) in complete Freund's adjuvant. Delayed hypersensitivity response
(DHR) was assayed by the increase in foot pad swelling after the intrafoot
pad injection of immune cells plus antigen. Cell-mediated cytotoxicity
against SRBC was assayed by a microcytotoxicity test with sheep fibroblasts
as target cells. Effector cells were antigen specific, sensitive to
anti-theta serum plus complement (C), and insensitive to anti-Ig serum plus
C. A nonrosette- forming (non-RFC) small lymphocyte effector T cell and a
rosette- forming medium lymphocyte effector T cell were isolated by
velocity sedimentation. The small lymphocyte non-RFC required a longer time
than the medium lymphocyte RFC effector cell to produce maximum activity.
Buoyant density failed to distinguish medium lymphocyte effector cells in
DHR and in vitro cytotoxicity.