Induction of immunity against human cytomegalovirus.

Most healthy individuals have been exposed to human cytomegalovirus (HCMV) and harbor the virus in a dormant form. However, in situations of immune compromise, HCMV infection is associated with high mortality rates in recipients of bone marrow transplants and with significant morbidity in recipients of solid organ transplants. Conventional vaccination with attenuated HCMV or HCMV proteins fails to prime protective immune responses, presumably because the antigens fail to be presented effectively in vivo. Dendritic cells (DC) are professional antigen-presenting cells that can be genetically engineered to direct their ability to induce immune responses toward immunodominant HCMV antigens. DC are a distinct lineage of leukocytes whose function is most notable for their ability to form clusters with T cells and stimulate vigorous cytotoxic T lymphocyte responses. We hypothesize that in this capacity, DC engineered to express HCMV antigens are uniquely positioned to control immunity against HCMV.