ABSTRACT
Biological and clinical effects of i.v. administration of gamma-globulin (0.9-1.5 g/kg) to 9 patients with infectious mononucleosis have been compared with the effects observed in 4 untreated patients. An increase of OKT4/OKT8 ratio has been measured in treated cases whereas this ratio remains low in untreated patients. Interleukin-2 secretion by stimulated lymphocytes increases also in treated patients but not in untreated ones. On the other hand gamma-globulin inhibits in vitro the cytotoxic activity of lymphocytes from immune subjects. Clinically gamma-globulin i.v. had a beneficial effect on the course of the disease and on adenopathies. As infectious mononucleosis has usually a favourable outcome, this treatment should be restrained to severe or chronic cases.