First Author | Weber KS | Year | 2012 |
Journal | Proc Natl Acad Sci U S A | Volume | 109 |
Issue | 24 | Pages | 9511-6 |
PubMed ID | 22645349 | Mgi Jnum | J:185522 |
Mgi Id | MGI:5429108 | Doi | 10.1073/pnas.1202408109 |
Citation | Weber KS, et al. (2012) Distinct CD4+ helper T cells involved in primary and secondary responses to infection. Proc Natl Acad Sci U S A 109(24):9511-6 |
abstractText | Helper T cells are critical for protective immunity, CD8(+) T-cell memory, and CD4(+) recall responses, but whether the same or distinct CD4(+) T cells are involved in these responses has not been established. Here we describe two CD4(+) T cells, LLO118 and LLO56, specific for an immunodominant Listeria monocytogenes epitope, with dramatically different responses to primary and secondary infection. Comparing in vivo responses, LLO118 T cells proliferate more strongly to primary infection, whereas surprisingly, LLO56 has a superior CD4(+) recall response to secondary infection. LLO118 T cells provide more robust help for CD8(+) T-cell responses to secondary infection than LLO56. We found no detectable differences in antigen sensitivity, but naive LLO118 T cells have much lower levels of CD5 and their T-cell receptor levels are dramatically down-regulated after their strong primary response. Thus, distinct CD4(+) helper T cells are specialized to help either in primary or secondary responses to infection. |