RESUMO
Measles virus infection reduces or abolishes delayed type hypersensitivity reactions (DTH) in humans. We have previously shown that the primary 2,4-dinitrofluorobenzene (DNFB) response is temporarily suppressed by measles virus in cotton rats. Here, we demonstrate that also the secondary DNFB response (cutaneous hypersensitivity [CHS]) is suppressed in cotton rats by measles virus infection. As in mice, DNFB specific CD8 T cells are the predominant T cell response in cotton rats. After MV infection, CD8 T cells are reduced in their proliferative capacity whereas the CD4/CD8 ratio, the number and activation status of CD8 T cells is not affected. As a result of impaired proliferation of DNFB specific T cells the DTH response (measured as ear swelling) is reduced in measles virus infected cotton rats. At the same time as DNFB specific T cell responses are suppressed, spontaneous proliferation of lymphocytes as evidence for immune activation is found.