[T- and B-lymphocyte determination in infectious mononucleosis].

In 12 children with infectious mononucleosis the peripheral blood T- and B-lymphocytes were studied and compared to a control group of 26 children, aged 2 to 13 years, without any infection. Spontaneous sheep red blood cell rosettes were used as a T-cell marker, demonstration of surface immunoglobulins by immunofluorescence technique was used as a B-cell marker. Patients with infectious mononucleosis showed a marked increase of T-lymphocytes (percentage and absolute numbers) in comparison with the control group; the difference was statistically significant. Since only B-lymphocytes are the target cells fo Epstein-Barr virus, the increase of T-lymphocytes in infectious mononucleosis probably represents the response of cell mediated immunity against B-lymphocytes which are altered in their antigenic properties by Epstein-Barr virus.