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CD169+ macrophages are sufficient for priming of CTLs with specificities left out by cross-priming dendritic cells.

ABSTRACT: Dendritic cells (DCs) are considered the most potent antigen-presenting cells (APCs), which directly prime or cross-prime MHC I-restricted cytotoxic T cells (CTLs). However, recent evidence suggests the existence of other, as-yet unidentified APCs also able to prime T cells. To identify those APCs, we used adenoviral (rAd) vectors, which do not infect DCs but selectively accumulate in CD169(+) macrophages (MPs). In mice that lack DCs, infection of CD169(+) MPs was sufficient to prime CTLs specific for all epitopes tested. In contrast, CTL responses relying exclusively on cross-presenting DCs were biased to selected strong MHC I-binding peptides only. When both DCs and MPs were absent, no CTL responses could be elicited. Therefore, CD169(+) MPs can be considered APCs that significantly contribute to CTL responses.

SUBMITTER: Bernhard CA

PROVIDER: S-EPMC4418891 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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CD169+ macrophages are sufficient for priming of CTLs with specificities left out by cross-priming dendritic cells.

Bernhard Caroline A CA Ried Christine C Kochanek Stefan S Brocker Thomas T

Proceedings of the National Academy of Sciences of the United States of America 20150414 17

Dendritic cells (DCs) are considered the most potent antigen-presenting cells (APCs), which directly prime or cross-prime MHC I-restricted cytotoxic T cells (CTLs). However, recent evidence suggests the existence of other, as-yet unidentified APCs also able to prime T cells. To identify those APCs, we used adenoviral (rAd) vectors, which do not infect DCs but selectively accumulate in CD169(+) macrophages (MPs). In mice that lack DCs, infection of CD169(+) MPs was sufficient to prime CTLs specif ...[more]

PMID: 25922518

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