63 MYCOPLASMA TESTS
á63ñ MYCOPLASMA TESTS
The genus Mycoplasma represents a group of minute bacteria which have no cell walls. The genus comprises more than 120
species. They are the smallest self-replicating prokaryotic organisms. The cells vary in size and morphology and cannot be Gram
stained, but impressions of colonies on solid agar can be stained with methylene blue or equivalent stain. Mycoplasma are
parasites and commensals, and some may be pathogenic to a variety of animal and plant hosts. In humans, Mycoplasma are
usually surface parasites that colonize the epithelial lining of the respiratory and urogenital tracts. Mycoplasma are common
and may cause serious contamination in cell and/or tissue cultures used to generate compendial articles. They may also cause
contamination of filtered sterilized soybean casein digest broth. A cell culture infection may persist for an extended period of
time without causing apparent cell damage. Infection of cells in a culture can affect nearly every pathway of cell metabolism,
including alteration of the cells’ phenotypical characteristics and normal growth. The presence of Mycoplasma species does not
always result in turbid growth in cultures or visible alteration of the cells.
Testing for Mycoplasma is a necessary quality control requirement to assure reliably pure biotechnological products and
allied materials used to generate these products. This general test chapter describes two methods required to detect
Mycoplasma contamination of test articles, tissues and/or cell cultures used to produce test articles, digest broth, or any other
material in which Mycoplasma contamination is suspected. These are: (A) the agar and broth media procedure and (B) the
indicator cell culture procedure. These tests require careful aseptic technique and suitable laboratory conditions. In order to
ensure appropriate testing and interpretation of results, personnel should be properly trained and qualified. A validated nucleic
acid amplification technique (NAT) or an enzymatic activity based method may be used to detect Mycoplasma, provided such a
method is shown to be comparable to both methods (A) and (B). Alternative methods must be suitably validated. Validation
requirements for alternate methods will not be addressed in this chapter.
