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A protein released by natural killer cells and cytotoxic T lymphocytes that causes lysis of target cells by forming pores in their membranes.

References in periodicals archive ?
Granulysin has a direct antimicrobial effect in vitro against fungi and gram-positive and gram-negative bacteria, and the lysis of mycobacteria by granulysin is intensified in the presence of perforin 1 (27).
12) Other cytotoxic T- lymphocyte mechanisms are regarded to play a role as well, such as Fas/Fas ligands or granulysis (a protein, discovered in granules of cytotoxic T-lymphocytes, which in combination with perforin reduces the vitality of a broad spectrum of pathogenic bacteria and through which T- cells directly contribute to the immunity against intracellular pathogens).
Human T regulatory cells can use the perforin pathway to cause autologous target cell death.
CD8+ T cells accomplish killing through multiple mechanisms, including the production of molecules like perforin and granzymes that literally punch holes in the macrophage membrane.
Lysis of infected epithelial cells is mediated by exocytosis granules containing perforin and granzymes (18,19).
sup][4] It is believed that CD8[sup]+ T-cells induce lung inflammation and emphysema in COPD by the production of granzyme B, perforin, and many other injurious and pro-inflammatory mediators.
Reduced release and binding of perforin at the immunological synapse underlies the age-related decline in natural killer cell cytotoxicity.
In Type IVc reactions, CD+8 cytotoxic T lymphocytes cause direct cell lysis by releasing enzymes including perforin and granzyme B.
Although the precise mechanism remains unclear, 1 currently accepted theory suggests the role of perforin and natural killer cells in HLH subtypes (9).