Phenotype of human alpha-interferon producing leucocytes identified by monoclonal antibodies

Monoclonal antibodies with specificities for subsets of human leucocytes have been used for the characterization of alpha-interferon (alpha-IFN) producing cells. The production of alpha-IFN was demonstrated to be a function of Ia+ leucocytes. OKT3+ T lymphocytes, BA-1+ B lymphocytes and Leu 7+ natural killer (NK) cells did not contribute to the production of alpha-IFN. OKM1+ monocytes were essential for the production of alpha-IFN in response to bacterial products or leukaemia cells, but were not required for the synthesis of virus- or poly I:C-induced alpha-IFN. The results indicate that alpha-IFN producing cells represent a heterogenous population of cells of the myeloid lineage.