T cell antigen receptor immune complexes demonstrating biologic and proteolytic activity.

An elastase-like protease, recently recognized as a specific product of murine T cells, may functionally associate with the classical TCR. T cell elastase, found in combination with the natural elastase inhibitor alpha 1-antitrypsin (alpha 1-protease inhibitor, alpha 1-PI), is produced by both CD4+ and CD8+ T lymphocytes. T cell elastase and alpha 1-PI are found chemically associated with the TCR in an antigen-specific complex reminiscent of the Ig-complement 'immune complexes'.