A non-pathogenic mycoplasma inhibiting the effect of a pathogenic mycoplasma in organ culture.

Abstract

Summary The pathogenic avian mycoplasma M. gallisepticum caused a 50 per cent. reduction of ciliary activity in chicken tracheal organ cultures after 4–5 days. Nine days were required for a similar loss of activity when the non-pathogenic mycoplasma M. gallinarum was introduced into the cultures 24 to 48 hr before M. gallisepticum. The protective effect occurred only with viable M. gallinarum organisms and did not involve inhibition of the growth of M. gallisepticum. The phenomenon was observed with most strains of M. gallisepticum and all strains of M. gallinarum tested. A single strain of M. hominis failed to protect the ciliary activity of M. gallisepticum-infected cultures. Chicken tracheal organ cultures infected with M. gallinarum alone showed more prolonged ciliary activity than cultures uninfected with any mycoplasma. The possible reasons for these phenomena are discussed.