Antigen-specific response among T lymphocytes following intestinal administration of alloantigens.

The kinetics of T lymphocyte responses to mucosally presented antigen and the appearance of antigen-reactive T cells in mucosal and systemic tissues have been investigated by measuring secondary mixed lymphocyte culture reactivity after intestinal administration of alloantigens. The data indicate that T lymphocytes in the intestine are able to respond to mucosally presented alloantigens, and that following immunisation the T cell reactivity occurs first in Peyer's patches then sequentially in mesenteric lymph nodes, thoracic duct lymph, gut lamina propria and distant mucosal sites. The response was mucosally restricted and the ultimate location of antigen-reactive cells is influenced by site of antigen administration. Evidence is also presented for the existence of systemic nonreactivity to mucosally presented antigens.