| abstract |
(57) [Summary] [Problem] CD28 positive T cell response and T Methods for modulating cell-mediated immune responses and assays for detecting ligands reactive with cell receptors that mediate cell-cell adhesion are provided. The present inventors have found that B7 antigen is a ligand reactive with CD28 receptor on T cells. Using the B7 antigen, fragments and derivatives thereof, and the CD28 receptor, fragments and derivatives thereof, and antibodies and other molecules reactive with the B7 antigen and / or CD28 receptor, are mediated by CD28 positive T cell responses, and T cells. Methods for modulating the immune response. The invention also encompasses assays that detect ligands that are reactive with cell receptors that mediate cell-cell adhesion. |