Natural killer (NK) cells, innate lymphocyte effectors, kill virus-infected host and tumor cells in non-MHC, non-TCR restricted fashion, unlike T cells. The role of NK cells in recognition and killing of pathogens remains unknown. Expression of the ten human pathogen associated molecular pattern or toll-like receptors (TLR's), associated molecules, and antimicrobial peptides alpha, beta defensins, and LL-37 by NK cells has not been investigated previously. We report our CD8+ NK/T cell line SRIK-NKL, derived from leukemic phase of acute lymphoblastic lymphoma, expresses mRNA and protein for 8/10 TLR's, associated proteins for signaling, defensins, cathelicidin/LL-37, and responds to live bacteria by cell proliferation and increased IFN-gamma, TNF-alpha, TNF-beta, and MIP-1alpha production.