Role of I-region gene products in T cell activation. I. Stimulation of T lymphocyte proliferative responses by subcellular membrane preparations containing Ia alloantigens
Germain, R.N.; Mayer, S.V.; Mescher, M.F.
Journal of Immunology 128(1): 506-511
1982
ISSN/ISBN: 0022-1767 PMID: 6172491 Document Number: 186070
A model system was developed for exploring the requirements for activation of T cells by subcellular forms of Ia alloantigen. Lymph node cells from mice recently primed s.c. with viable allogeneic cells show strong proliferative responses in vitro to membrane preparations derived from cells bearing the appropriate I-region-encoded glycoproteins. This stimulation shows kinetics characteristic of a secondary response, with a peak at 24-48 h. Primary responses to alloantigen-bearing membranes are weak or absent under these conditions. The predominant cell type involved in the secondary response is the Lyt-1+ T lymphocyte and the major antigenic stimulus is the I-A subregion-encoded Ia glycoprotein. Syngeneic Ia+ accessory cells do not appear necessary for activation to occur. Detergent solubilized reconstituted membrane vesicles also stimulate primed T lymphocytes to respond by proliferation. The applications of this approach to the study of T cell recognition of antigen and the role of nonspecific lymphokines in T cell triggering are discussed.