HUMAN CYTOMEGALOVIRUS NEUTRALIZING ANTIBODY-RESPONSE IN JAPANESE CHILDREN WITH BONE-MARROW TRANSPLANTATION

Thirty-two children with bone barrow transplantation (BMT) received in travenous injections of gammaglobulin (IVIG) with a high titer of neut ralizing (NT) antibody against human cytomegalovirus (HCMV) (200 mg/kg /week) from 1 week before to 4 months after transplantation. NT antibo dy titers before BMT and the highest levels in serial determinations c onducted after BMT were compared for each patient. They mere classifie d into three groups according to the antibody response: primary HCMV i nfection as group I, endogenous reactivation or external reinfection a s group II, and indeterminable cases as group III. Two (6.3%) out of 3 2 patients examined had BMT-associated primary HCMV infections, but di d not show any clinical symptoms. Significant changes in clinical para meters mere also lacking in all the other 30 patients, independent of whether they shed viruses into the urine, or demonstrated on antibody boost. It was concluded from the group variation that the antibody res ponse was indeed due to the engraftment of BMT, rather than to a direc t effect of treatment with IVIG. Our results further indicate that pas sive immunization with HCMV antibody does not prevent infection, but c onfers some protection against symptomatic disease.