| First Author | Lu Z | Year | 2000 |
| Journal | J Exp Med | Volume | 191 |
| Issue | 3 | Pages | 541-50 |
| PubMed ID | 10662799 | Mgi Jnum | J:115118 |
| Mgi Id | MGI:3690688 | Doi | 10.1084/jem.191.3.541 |
| Citation | Lu Z, et al. (2000) CD40-independent pathways of T cell help for priming of CD8(+) cytotoxic T lymphocytes. J Exp Med 191(3):541-50 |
| abstractText | In many cases, induction of CD8(+) CTL responses requires CD4(+) T cell help. Recently, it has been shown that a dominant pathway of CD4(+) help is via antigen-presenting cell (APC) activation through engagement of CD40 by CD40 ligand on CD4(+) T cells. To further study this three cell interaction, we established an in vitro system using dendritic cells (DCs) as APCs and influenza hemagglutinin (HA) class I and II peptide-specific T cell antigen receptor transgenic T cells as cytotoxic T lymphocyte precursors and CD4(+) T helper cells, respectively. We found that CD4(+) T cells can provide potent help for DCs to activate CD8(+) T cells when antigen is provided in the form of either cell lysate, recombinant protein, or synthetic peptides. Surprisingly, this help is completely independent of CD40. Moreover, CD40-independent CD4(+) help can be documented in vivo. Finally, we show that CD40-independent T cell help is delivered through both sensitization of DCs and direct CD4(+)-CD8(+) T cell communication via lymphokines. Therefore, we conclude that CD4(+) help comprises at least three components: CD40-dependent DC sensitization, CD40-independent DC sensitization, and direct lymphokine-dependent CD4(+)-CD8(+) T cell communication. |
