| First Author | Wong KL | Year | 2009 |
| Journal | J Immunol | Volume | 183 |
| Issue | 1 | Pages | 41-50 |
| PubMed ID | 19535645 | Mgi Jnum | J:150109 |
| Mgi Id | MGI:3849754 | Doi | 10.4049/jimmunol.0803473 |
| Citation | Wong KL, et al. (2009) CD44(high) memory CD8 T cells synergize with CpG DNA to activate dendritic cell IL-12p70 production. J Immunol 183(1):41-50 |
| abstractText | Protective memory CD8 T cell responses are generally associated with the rapid and efficient acquisition of CTL function. However, the ability of memory CD8 T cells to modulate immune responses through interactions with dendritic cells (DCs) during the early states of secondary Ag exposure is poorly understood. In this study, we show that murine Ag-specific CD44(high) CD8 T cells, representing CD8 T cells of the memory phenotype, potently activate DCs to produce high levels of IL-12p70 in conjunction with stimulation of DCs with the TLR 9 ligand, unmethylated CpG DNA. IL-12p70 production was produced predominantly by CD8alpha(+) DCs and plasmacytoid DCs, and mediated by CD8 T cell-derived cytokines IFN-gamma, GM-CSF, TNF-alpha, and surface CD40L. We also find that CD44(high) memory phenotype CD8 T cells were better DC IL-12p70 stimulators than CD44(low) naive phenotype CD8 T cells, and this was attributed to higher levels of IFN-gamma and GM-CSF produced by CD44(high) memory phenotype CD8 T cells during their Ag specific interaction with DCs. Our study identifies CpG DNA as the most effective TLR ligand that cooperates with CD8 T cells for DC IL-12p70 production, and suggests that effectiveness of memory CD8 T cells could be attributed to their ability to rapidly and effectively induce protective Th1 immunity during early stages of pathogen reinfection. |
