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.