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Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing.

ABSTRACT: Natural killer (NK) cells can mediate the rejection of bone marrow allografts and exist as subsets based on expression of inhibitory/activating receptors that can bind MHC. In vitro data have shown that NK subsets bearing Ly49 receptors for self-MHC class I have intrinsically higher effector function, supporting the hypothesis that NK cells undergo a host MHC-dependent functional education. These subsets also play a role in bone marrow cell (BMC) allograft rejection. Thus far, little in vivo evidence for this preferential licensing across mouse strains with different MHC haplotypes has been shown. We assessed the intrinsic response potential of the different Ly49(+) subsets in BMC rejection by using ?2-microglobulin deficient (?2m(-/-)) mice as donors. Using congenic and allogeneic mice as recipients and depleting the different Ly49 subsets, we found that NK subsets bearing Ly49s, which bind "self-MHC" were found to be the dominant subset responsible for ?2m(-/-) BMC rejection. This provides in vivo evidence for host MHC class I-dependent functional education. Interestingly, all H2(d) strain mice regardless of background were able to resist significantly greater amounts of ?2m(-/-), but not wild-type BMC than H2(b) mice, providing evidence that the rheostat hypothesis regarding Ly49 affinities for MHC and NK-cell function impacts BMC rejection capability.

SUBMITTER: Sun K

PROVIDER: S-EPMC3286220 | biostudies-other | 2012 Feb

REPOSITORIES: biostudies-other

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Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing.

Sun Kai K Alvarez Maite M Ames Erik E Barao Isabel I Chen Mingyi M Longo Dan L DL Redelman Doug D Murphy William J WJ

Blood 20111219 6

Natural killer (NK) cells can mediate the rejection of bone marrow allografts and exist as subsets based on expression of inhibitory/activating receptors that can bind MHC. In vitro data have shown that NK subsets bearing Ly49 receptors for self-MHC class I have intrinsically higher effector function, supporting the hypothesis that NK cells undergo a host MHC-dependent functional education. These subsets also play a role in bone marrow cell (BMC) allograft rejection. Thus far, little in vivo evi ...[more]

PMID: 22184406

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Dataset Information

Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing.

Publications

Mouse NK cell-mediated rejection of bone marrow allografts exhibits patterns consistent with Ly49 subset licensing.

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