Specific cellular unreactivity during cytomegalovirus infection in man.

The specific cellular immune response against Cytomegalovirus (CMV) was studied by the Leucocyte Inhibitory Factor (LIF) production test in three groups of subjects: 7 healthy individuals with no CMV antibodies, 4 with antibodies to CMV but without evidence of active infection, and 2 children with clinical CMV infection. Our results show that LIF production in presence of CMV is high in normal seropositive subjects, while it is strongly deficient in patients with active infection, despite a good humoral response to the virus. In one child with congenital infection, a low number of E rosette forming cells was also revealed. We suggest that CMV infection can induce, at least during infancy, a state of specific cellular unresponsiveness to the virus. When the infection is congenital, a generalized depression of the cellular immune system may develop.