Natural killer (NK) cells provide a vital link between innate and adaptive immunity and play a specific role in protection against tumors and viruses. Several lines of study have shown that NK cells operate through signals delivered by inhibitory and activation receptors, yet direct evidence for activation receptors in protection against pathogens has been lacking. Brown et al. show that the NK activation receptor, LY-49H, plays a critical role in the resistance of mice to infection with cytomegalovirus. LY-49 contains immunoreceptor tyrosine activation motif normally found in lymphocyte membrane receptors, which suggests that NK cells may operate through similar pathways of cell signaling as the cells of the adaptive immune response.
M. G. Brown, A. O. Dokun, J. W. Heusel, H. R. C. Smith, D. L. Beckman, E. A. Blattenberger, C. E. Dubbelde, L. R. Stone, A. A. Scalzo, W. M. Yokoyama, Vital involvement of a natural killer cell activation receptor in resistance to viral infection. Science 292, 934-937 (2001). [Abstract] [Full Text]