Flow Cytometric Evaluation of Granzyme B May More Accurately Assess Effector Cell Function in CD8 Positive T Cells

Cytotoxic effector lymphocytes (CTL) are the premier line of defense in viral infection or tumor infiltration. Granzyme B is the main weapon in the CTL arsenal. Granzyme B is a serine protease found primarily in natural killer (NK) cells and CTL and it acts by means of inducing apoptosis in target cells. Contact between CTL and target cells results in directed exocytosis of the CTL granules and penetrance into target by means perforin-polymerized target-cell pores. This poster assesses whether measurement of granzyme B may be a more accurate assessment of cytotoxic T cell and NK activation, and thus more indicative of an acute cytotoxic response.