| First Author | Reichmann G | Year | 2000 |
| Journal | Infect Immun | Volume | 68 |
| Issue | 3 | Pages | 1312-8 |
| PubMed ID | 10678943 | Mgi Jnum | J:60577 |
| Mgi Id | MGI:1353688 | Doi | 10.1128/iai.68.3.1312-1318.2000 |
| Citation | Reichmann G, et al. (2000) The CD40/CD40 ligand interaction is required for resistance to toxoplasmic encephalitis. Infect Immun 68(3):1312-8 |
| abstractText | Since the CD40/CD40 ligand (CD40L) interaction is involved in the regulation of macrophage production of interleukin 12 (IL-12) and T-cell production of gamma interferon (IFN-gamma), effector cell functions associated with resistance to Toxoplasma gondii, the role of CD40L in immunity to this parasite was assessed. Infection of C57BL/6 mice with T. gondii results in an upregulation of CD40 expression on accessory cell populations at local sites of infection as well as in lymphoid tissues. Splenocytes from C57BL/6 mice infected with T. gondii for 5 days produced high levels of IL-12 and IFN-gamma when stimulated with toxoplasma lysate antigen, and blocking CD40L did not significantly alter the production of IFN-gamma or IL-12 by these cells. Similar results were observed with splenocytes and mononuclear cells isolated from the brains of chronically infected mice. Interestingly, although CD40L(-/-) mice infected with T. gondii produced less IL-12 than wild-type mice, they produced comparable levels of IFN-gamma but succumbed to toxoplasmic encephalitis 4 to 5 weeks after infection. The inability of CD40L(-/-) mice to control parasite replication in the brain correlated with the ability of soluble CD40L, in combination with IFN-gamma, to activate macrophages in vitro to control replication of T. gondii. Together, these results identify an important role for the CD40/CD40L interaction in resistance to T. gondii. However, this interaction may be more important in the control of parasite replication in the brain rather than the generation of protective T-cell responses during toxoplasmosis. |
