Résumé : Monoclonal antibodies were used to determine the levels of circulating helper and suppressor T cells in 34 infants and adults with severe atopic dermatitis and in normal controls. The percentage of OKT3 (total T lymphocytes) was reduced significantly in all the atopic infants. The percentage of OKT8 (suppressor-cytotoxic T lymphocytes) was reduced significantly in all patients with active lesions. The percentage of Tγ lymphocytes was reduced in all the atopic patients with or without active lesions.