Changes in T-lymphocyte subsets during childhood Epstein-Barr virus infectious mononucleosis.

Lymphocyte subsets were measured using monoclonal antibodies in 11 children with Epstein-Barr virus-induced infectious mononucleosis and compared with those of 10 normal children. In acute infectious mononucleosis the percentage of T8+ lymphocytes was greater while the percentage of T4+ lymphocytes and the T4+ to T8+ ratio were less than those measured in normal children. The percentage and absolute number of T lymphocytes, as enumerated by E rosetting, did not differ from the values for normal children. The children with acute infectious mononucleosis had a somewhat lower T8+ response than that observed in four adult infectious mononucleosis patients. With clinical recovery, the T lymphocyte-subset values returned toward normal. T8+ lymphocytes, a phenotype subset with predominantly suppressor activity, presumably reduce normal cellular immune functions transiently and may limit the continued proliferation of Epstein-Barr virus-infected B lymphocytes.