Studies on leukocyte cultures in measles. II. Detection of measles virus antigen in human leucocytes by immunofluorescence.

Abstract

Leukocyte cultures from 10 measles cases were tested by immunofluorescence for the presence of measles virus antigen. The antigen was not detected in the cells before culture but became demonstrable in cells from 9 of the patients after PHA stimulation. Antigen was detected on the surface membrane of 2 to 30 per cent of blast cells, and all giant cells when present. Antigen was also demonstrable in the cytoplasm but not the nucleus of giant cells and blast cells. Unstimulated leukocyte cultures from the measles patients were negative. PHA-stimulated and unstimulated cultures from healthy blood donors were also negative. It was concluded that some circulating lymphoid cells of measles patients carry measles virus and that virus replication proceeded more rapidly in the transformed (proliferating) lymphocytes than in resting ones. The relevance of these observations to the severity of measles in certain communities, and to the immunosuppressive effects of measles is discussed.