Adoptive Immunotherapy for Interstitial Pneumonia Associated with Cytomegalovirus Infection

Primary infection with cytomegalovirus (CMV) usually follows a benign course, but the virus remains latent or persistent in the host cell. Under immunosuppressive conditions, latent or persistent infection can be reactivated to produce a wide variety of clinical manifestations. Some antiviral agents that are active against virus-specific metabolic processes without producing cytotoxicity have become available. Unfortunately, no successful treatment of CMV infection in children has yet been developed. Adoptive transfer of antigen-specific cytotoxic T lymphocytes (CTLs) offers safe and effective therapy for certain viral infections. Walter et al. provided important evidence that infusion of donor-derived CD8 super(+) cytotoxic T cell clones specific for CMV can promptly reconstitute cellular immunity against CMV in recipients of allogenic bone marrow, thus reducing the risk of morbidity and mortality related to viral infection. However, the persistence of transferred CD8 super(+) cytotoxic cells was prompted by the recovery of the response of CD4 super(+) CMV-specific helper T cells. The infusion of virus-specific polyclonal T cell lines containing both CD4 super(+) and CD8 super(+) cells has been successfully used to control infection with Epstein-Barr virus (EBV) and related lymphoproliferative disorders in recipients of allogenic bone marrow. Heslop et al. reported that infusions of CTLs not only restored cellular immune response against EBV but also established that populations of CTL precursors could respond to the challenge.