[Cytomegalovirus and immunomodulation]

Cytomegalovirus (CMV) has close relationship with the immune system. Latency, reactivation and transforming effect are common features seen during its cellular localization, explaining the main importance of cellular immunity in the host defence. Host-graft induced immunosuppression and drugs are 2 important parameters involved in the frequency and the severity of CMV infection in organ transplantation. On the other hand, CMV and cellular rejection are tightly implicated both inducing the other and vice versa. In the host defence, NK cells, cytotoxic T lymphocytes and antibody dependent cell cytotoxicity are 3 lytic mechanisms successively involved and limiting or curing acute or chronic infection. Moreover, CMV has a transforming effect and could be implicated in some Kaposi sarcoma.