Inactivation of mycoplasma in seed virus stocks using gamma radiation

A method was developed for the elimination of viable Mj~cop/asl~la in reference seed virus stocks. It was found that various species of M)~coplastna (such as M. pnertn~onrae, M. arthritidis, M. ho~ni~lis, M. salivarirrm, M. orale types I and 11, M. n7eleagrirlis, and several unidentified species isolated from tissue cultures) were inactivated more rapidly by gamma radiation than all viruses tested. By the use of selected radiation doses, high concentrations of Mj~cop/asnla species could be inactivated in virussuspensions of polioviruses types I and 111, coxsackie viruses types A-7, A-9, B-3, and B-6, echoviruses types 1, 9, 12, and 20, herpes simplex, rubella, measles, and adenovirus type 70, without inactivating all viable virus. After irradiation, the remaining viable virus could be propagated as well as the original strain and showed no change in reactivity with homologous or heterologous antisera. After storage for 2 months at -70°C, the irradiated virus showed no decrease either in viability or in specific reactivity. By this method, reference seed virus stocks could be prepared free of viable Afycoplas~~m species, without dependence on tissue cultures free of Mycoplaatm. POLLEY, J. R., et A. G. FANOK. 1973. Inactivation of Mycoplast~~a in seed virus stocks using gamma radiation. Can. J. Microbiol. 19: 709-714. Une ~ntthode a Cte dCvcloppte pour elirniner des especes de M)~coplasmn viables de cultures de virus de reference. 11 a ete trouve que differentes especes de Mycoplasma (par exe~nple M. pt1errn7orriae, M. urlhriiidis, M. lrominis, M. salivarirml, les types I et 11 de M. ornle, M. meleagridis et plusieurs espttces non identifites isoltes de culti~res de tissu) sont inactivees plus rapidement par des rayons gamma que tous lesvirus essayb. Par dosage approprit des rayons, des concentrations elevees des especes de Mycoplost~~a ont pu &tre inactivees dans des suspensions des poliovirus I et 111, des types A-7, A-9, B-3 et B-6 des virus coxsackie, des types 1, 9, 12 et 20 des virus echo, des virus de I'herpis simplex, de la rubCole, de la rougeole et du type 70 des adenovirus, sans inactivation complete des virus viables. Apres irradiation, les virus survivants sont propages aussi bien que les souches originales, sans changement de leurs reactions avec des antiserums hornologues ou heterologues. Gardks pendant 2 mois a -70°C, les virus irradiis ne nlontrent pas de diminution de titreou de rtactivite antigenique. Par cette methode, des cultures de virus de reference sans des especes de Mycoplosma viables peuvent &tre obtenues sans avoir recours A des cultures de tissu exempts de M~~coplasr~~n. [Traduit par le journal]