| Abstract: | Hepatitis B surface antigen (HBsAg) was detected by a monoclonal antibody radioimmunoassay in sera from five of 43 children (11.6%) with acute leukemia, who were negative by conventional assay. None of the nine positive sera had evidence of reactivity for HBV-DNA or DNA-polymerase activity. No correlation was found between the presence of HBsAg in serum by monoclonal RIA and the behaviour of anti-viral antibodies. Twenty-two children could be studied for liver HBsAg by immunofluorescence, and nine of them (40.9%) were positive, including three patients having HBsAg reactivity in serum. These data indicate that monoclonal antibodies increase the sensitivity of RIA for the detection of serum HBsAg in children with acute leukemia, who previously have frequently been found to have an atypical hepatitis B virus (HBV) serology. |
