Differential expression of granzyme A and granzyme B proteases and their secretion by fresh rat natural killer cells (NK) and lymphokine‐activated killer cells with NK phenotype (LAK‐NK)

摘要

AbstractGranzymes A—G are a family of serine proteases localized in the cytoplasmic granules of cytotoxic T lymphocytes (Masson, D. et al.Cell1987.49:679) and granzyme A is secreted by T lymphocytes in response to antigenic stimulation. Granzyme A is also expressed by natural killer (NK) and lymphokine‐activated killer (LAK) cells. Here we show that fresh rat NK cells constitutively express granzyme B and that granzyme A and granzyme B are differentially regulated in unstimulated NK cellsvs. LAK cells with NK phenotype (LAK‐NK cells). We also show that both granzymes A and B are secreted in a calcium‐dependent manner, by NK and LAK‐NK cells in response to stimuli which trigger NK cell