Article

Mouse Ly49G2+ NK cells dominate early responses during both immune reconstitution and activation independently of MHC.

Department of Microbiology and Immunology, University of Nevada, Reno, Reno, NV, USA.
Blood (impact factor: 9.9). 04/2011; 117(26):7032-41. DOI:10.1182/blood-2010-11-316653 pp.7032-41
Source: PubMed

ABSTRACT Natural killer (NK) cell subsets can be defined by the differential expression of inhibitory receptors for MHC class I molecules. Early after congenic HSCT, we found that Ly49G2(high) single-positive NK cells repopulated, displayed an activated phenotype, and were highly cytolytic. Over time, this subset was replaced with NK cells with a normal pattern of Ly49 expression. Treatment of mice with IL-2 also resulted in the rapid expansion of these Ly49G2(high) single-positive NK cells. Only the Ly49g (Klra7) Pro1 transcript was highly induced in both HSCT- and IL-2-treated recipients. MHC-independent expansion of the Ly49G2(+) subset was also observed after Listeria monocytogenes or mouse cytomegalovirus infection. Our data indicate that during reconstitution after HSCT and various activation stimuli, Ly49G2(+) NK cells represent the "first-responder" NK cells, which occur independently of NK-cell licensing via Ly49-MHC interactions. These data suggest that the inhibitory Ly49G2 receptor represents an activation marker on mouse NK cells under various conditions.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

activated phenotype
 
congenic HSCT
 
first-responder
 
HSCT
 
HSCT-
 
IL-2
 
IL-2-treated recipients
 
inhibitory Ly49G2 receptor
 
inhibitory receptors
 
Klra7
 
Listeria monocytogenes
 
Ly49-MHC interactions
 
MHC-independent expansion
 
mouse cytomegalovirus infection
 
mouse NK cells
 
NK
 
NK cells
 
NK-cell licensing
 
rapid expansion
 
various conditions