First Author | Shepherd DM | Year | 1999 |
Journal | J Immunol | Volume | 163 |
Issue | 5 | Pages | 2470-7 |
PubMed ID | 10452982 | Mgi Jnum | J:57099 |
Mgi Id | MGI:1343678 | Doi | 10.4049/jimmunol.163.5.2470 |
Citation | Shepherd DM, et al. (1999) Disruption of CD154:CD40 blocks generation of allograft immunity without affecting APC activation. J Immunol 163(5):2470-7 |
abstractText | CD154 (CD40 ligand, gp39) interaction with its receptor CD40 has been shown to be critically important for the generation of cell-mediated as well as humoral immunity. It has been proposed that ligation of CD40 on APCs, presumably by activated Th cells, leads to increased APC function as defined by up-regulation of costimulatory molecules and enhancement of IL-12 production. In this report, we directly examined the contribution of the CD154:CD40 pathway in a murine model of allograft rejection. Generation of both the CTL and alloantibody responses following injection with allogeneic P815 tumor cells was severely compromised in CD154 knockout mice and wild-type C57BL/6 mice treated with the anti-CD154 mAb, MR1. Splenic production of IL-2, IFN-gamma, and TNF was significantly suppressed from CD154-deficient mice, indicating a lack of T cell priming. However, splenic cells from CD154 knockout mice induced comparable levels of CD86 expression and IL-12 production when compared with their wild-type littermates. The treatment of CD154-/- mice with the agonistic anti-CD40 mAb, FGK45, generated activated APCs yet failed to restore either the CTL or alloantibody responses to P815. Likewise, immunization with B7-transfected P815 tumor cells failed to generate expansion of the CTL effector population in CD154-/- mice. These results suggest that the generation of allograft immunity is dependent on the interaction of CD154 with CD40 but not primarily for the activation of APCs. |