Specific and nonspecific NK cell activation during virus infection

Abstract

The natural killer (NK) cell activation receptor Ly49H is required for resistance to murine cytomegalovirus (MCMV). We show here that NK cell proliferation and production of interferon-gamma (IFN-gamma) was not dependent on Ly49H expression during early MCMV infection. During a later phase of infection, however, Ly49H+ NK cells selectively proliferated and this expansion was blocked by anti-Ly49H administration. With vaccinia virus infection, neither the early nor late phase of NK cell proliferation was selective for Ly49H+ NK cells. These findings indicated that Ly49H+ NK cells were specifically activated by MCMV and that MCMV infection was characterized by nonspecific and specific phases of NK cell activation in vivo.

Requirements for control of B‐cell lymphoma by NK cells

“…2C) that are strong NK-cell stimulators [31,32], we examined whether NK cell-activating agents may delay tumor development in vivo through an NK cellmediated mechanism. We therefore treated clinically unapparent l-myc mice with CpG-ODN 1668 for several weeks.…”

Sweet Is the Memory of Past Troubles: NK Cells Remember

“…In a similar manner, mouse CMV (MCMV) has coevolved with its host for long enough to impact the NK receptor repertoire. NK cells from C57BL/6 (B6) mice carry a germline-encoded activating receptor, Ly49H, that specifically recognizes the MCMV-encoded protein m157 (Lee et al 2001;Arase et al 2002;Dokun et al 2001;Smith et al 2002). The MCMV model has established a critical role for NK cells in controlling host resistance to infection (Scalzo et al 1992), which is, in part, driven by recognition of m157 by Ly49H.…”

Homéostasie des cellulesnatural killer

“…En effet, la reconnaissance par les cellules NK des souches de MCMV couramment utilisées au laboratoire dépend du récepteur Ly49H qui reconnaît très spécifiquement une protéine virale, appelée m157, exprimée à la surface des cellules infectées [28]. L'interaction entre m157 et Ly49H entraîne une prolifération intense des cellules NK Ly49H + qui représentent environ 50 % des cellules NK à l'état basal [29]. Lorsqu'un petit nombre de cellules NK Ly49H + est transféré à des souris Ly49H -qui sont ensuite infectées par MCMV, l'expansion des cellules NK Ly49H + est comparable à l'expansion clonale des précur-seurs T naïfs qui a lieu lors de leur rencontre avec l'antigène spécifique [30].…”