Cryopreservation and storage of Mycoplasma spp.

[摘要] Cryopreservation has as a principle to maintain cell viability and functionality at low temperatures; thus, to understand and properly implement cryopreservation of biological material is essential in laboratories and cell banks. In the case of mycoplasmas, maintenance of viable cultures is not only an operational issue, but also an essential factor in the good performance of the laboratory work. Therefore, this study aimed to assess the viability of mycoplasma strains preserved by freezing, in different matrices and several cryopreserving agents. For the study, it was used a culture of Mycoplasma hyorhinis (selected as type strain) with 5,1x108UFC/ml, which was inoculated into cell culture matrices and ascetic liquid. Both types of samples were stored at -70ºC and -20ºC by using or not cryopreserving agents; in this case, 5% glycerol and 2.5% dimethylsulfoxide were used. At 3, 30, 60 and 90 days postfreezing, mycoplasma viability was checked by growing them in liquid and solid Hayflick's media. As a result, it was found that in the matrices frozen at -20ºC and -70ºC and cryopreserving, Mycoplasma hyorhinis remained viable for 90 days, but not in the matrices containing no cryopreserving, where the behavior was variable depending on the temperature. It was concluded that the addition of cryopreserving agents (5% glycerol or 2.5% dimethylsulfoxide) preserved the viability of mycoplasmas in the matrices studied during freezing and subsequent storage; also the temperature of -20ºC can be used by those laboratories lacking equipment with -70ºC to store samples for three months, period of time designed for interlaboratory studies.

[学科分类] 兽医学

[关键词] mycoplasmas;cryopreservation;storage;quality;diagnosis