| First Author | Miyakoda M | Year | 2008 |
| Journal | J Immunol | Volume | 181 |
| Issue | 2 | Pages | 1420-8 |
| PubMed ID | 18606696 | Mgi Jnum | J:137658 |
| Mgi Id | MGI:3801399 | Doi | 10.4049/jimmunol.181.2.1420 |
| Citation | Miyakoda M, et al. (2008) Malaria-specific and nonspecific activation of CD8+ T cells during blood stage of Plasmodium berghei infection. J Immunol 181(2):1420-8 |
| abstractText | Cerebral malaria is one of the severe complications of Plasmodium falciparum infection. Studies using a rodent model of Plasmodium berghei ANKA infection established that CD8(+) T cells are involved in the pathogenesis of cerebral malaria. However, it is unclear whether and how Plasmodium-specific CD8(+) T cells can be activated during the erythrocyte stage of malaria infection. We generated recombinant Plasmodium berghei ANKA expressing OVA (OVA-PbA) to investigate the parasite-specific T cell responses during malaria infection. Using this model system, we demonstrate two types of CD8(+) T cell activations during the infection with malaria parasite. Ag (OVA)-specific CD8(+) T cells were activated by TAP-dependent cross-presentation during infection with OVA-PbA leading to their expression of an activation phenotype and granzyme B and the development to functional CTL. These highly activated CD8(+) T cells were preferentially sequestered in the brain, although it was unclear whether these cells were involved in the pathogenesis of cerebral malaria. Activation of OVA-specific CD8(+) T cells in RAG2 knockout TCR-transgenic mice during infection with OVA-PbA did not have a protective role but rather was pathogenic to the host as shown by their higher parasitemia and earlier death when compared with RAG2 knockout mice. The OVA-specific CD8(+) T cells, however, were also activated during infection with wild-type parasites in an Ag-nonspecific manner, although the levels of activation were much lower. This nonspecific activation occurred in a TAP-independent manner, appeared to require NK cells, and was not by itself pathogenic to the host. |
