Production of immune and viral interferon by lymphocytes of newborn infants.

The ability of lymphocytes from newborn infants to produce two types of interferon was compared with that of lymphocytes from older children and adults. Cord blood lymphocytes were as capable of producing both viral interferon (stable at pH 2.0) following stimulation with polyriboinosinic acid-polyribocytidilic acid and immune interferon (unstable at pH 2.0) following stimulation with phytohemagglutinin as lymphocytes from older individuals. In a mixture of mononuclear and polymorphonuclear cells, it was the former that produced the interferon. Interferon may be important in the defense mechanism of the newborn infant against viruses and other microbial agents.