| First Author | Jehl SP | Year | 2011 |
| Journal | Infect Immun | Volume | 79 |
| Issue | 5 | Pages | 2021-30 |
| PubMed ID | 21357720 | Mgi Jnum | J:171947 |
| Mgi Id | MGI:5002429 | Doi | 10.1128/IAI.00939-10 |
| Citation | Jehl SP, et al. (2011) Antigen-Specific CD8+ T Cells Fail To Respond to Shigella flexneri. Infect Immun 79(5):2021-30 |
| abstractText | CD8(+) T lymphocytes often play a primary role in adaptive immunity to cytosolic microbial pathogens. Surprisingly, CD8(+) T cells are not required for protective immunity to the enteric pathogen Shigella flexneri, despite the ability of Shigella to actively secrete proteins into the host cytoplasm, a location from which antigenic peptides are processed for presentation to CD8(+) T cells. To determine why CD8(+) T cells fail to play a role in adaptive immunity to S. flexneri, we investigated whether antigen-specific CD8(+) T cells are primed during infection but are unable to confer protection or, alternatively, whether T cells fail to be primed. To test whether Shigella is capable of stimulating an antigen-specific CD8(+) T-cell response, we created an S. flexneri strain that constitutively secretes a viral CD8(+) T-cell epitope via the Shigella type III secretion system and characterized the CD8(+) T-cell response to this strain both in mice and in cultured cells. Surprisingly, no T cells specific for the viral epitope were stimulated in mice infected with this strain, and cells infected with the recombinant strain were not targeted by epitope-specific T cells. Additionally, we found that the usually robust T-cell response to antigens artificially introduced into the cytoplasm of cultured cells was significantly reduced when the antigen-presenting cell was infected with Shigella. Collectively, these results suggest that antigen-specific CD8(+) T cells are not primed during S. flexneri infection and, as a result, afford little protection to the host during primary or subsequent infection. |
