The Role of Granzyme B in Cytotoxic T Lymphocyte Assisted Suicide

Abstract

Two branches have evolved in the immune system to recognize foreign molecules and thus protect against pathogens. In humoral immunity, antibodies are produced that bind to these specific structures and hence stimulate their removal by phagocytosis or complement mediated lysis. T lymphocytes have on their surface a receptor that, like antibodies, binds to foreign peptides presented in the context of the major histocompatibility proteins. As a result the effectors of cell mediated immunity, the cytotoxic T lymphocytes, become activated and can then recognize and destroy any antigen expressing pathogenic cell. This branch of the immune system is particularly involved in the eradication of virus infected cells, but also may play a role in lysis of tumors, transplanted cells and in the destruction of normal host cells in autoimmune disorders.