Mycoplasma-mediated hyporeactivity to various interferon inducers.

Three strains of Mycoplasma arthritidis were shown to induce marked hyporeactivity in mice to interferon induction by both Newcastle disease virus and poly(I:C). In contrast, the interferon response of mice to tilorone was only partially suppressed by pretreatment of the animals with mycoplasms. Hyporeactivity to Newcastle disease virus was maximal 1 and 3 days after mycoplasms treatment, but the interferon response was maximal 1 day after injection of the mycoplasmas and was no longer apparent by 5 days. No relationship was found between the ability of the mycoplasms themselves to induce interferon and the degree of hyporeactivity produced. These results suggest that mycoplasmas may alter virus-host relationships in vivo.