Preferential lysis of undifferentiated thymocytes by natural thymocytotoxic antibodies from New Zealand black mice.
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Autoimmune NZB mice spontaneously develop auto-antibodies to thymus-dependent lymphocytes. These naturally occurring thymocytotoxic antibodies (NTA) were studied for their ability to lyse, in vitro, thymocytes undergoing Con A-induced in vitro proliferation and thymocytes undergoing natural in vivo differentiation. NTA were preferentially cytolytic for immature thymocytes. Thymocytes stimulated with Con A for 48 hr were less susceptible to lysis by NTA than were control thymocytes pulsed with Con A for 5 min. Conversely, thymocytes stimulated with Con A for 48 hr were more susceptible to lysis by anti-H-2 antibodies than were control thymocytes pulsed with Con A for 5 min. In addition, when thymocytes were fractionated by peanut agglutinin (PNA), the PNA (+) fraction (immature thymocytes) was more readily lysed by NTA than was the PNA (-) fraction (maturing thymocytes). These results suggest that NTA may play a role in the development of autoimmunity in NZB mice by sequentially eliminating thymus-dependent lymphocytes on the basis of the quantity of NTA-reactive antigen on their surfaces. Similar studies were performed by using AKR anti-C3H serum that contained anti-Thy 1.2 antibodies and autothymocytotoxic antibodies (reactive with AKR thymocytes). Appropriate titers of both the Thy 1.2 and the autothymocytotoxic antibodies also had greater cytolytic activity against 5 min Con A-pulsed or PNA (+) thymocytes compared with 48 hr Con A-stimulated or PNA (-) thymocytes, respectively. Thus, the cytolytic activity observed in the AKR anti-C3H serum was analogous to that observed with NTA. These results suggest that appropriate titers of Thy 1 antisera may preferentially kill subpopulations of T lymphocytes in a manner similar to NTA.
