mycoplasm contamination - (Jul/04/2006 )

Does anyone has experience for mycoplasm detection postinfection? We have problems. before we do infection we checked the phoenix package cell and MEF cells to be infected, both of them are well negative. while after infection, two time the infected cells become mycoplasm positive. moreover, the cells grows well without changing the speed of growth. We do the test because we have the problems before. otherwise, by looking cells growth, we will never doult the contamination problem.

is there the possiblity that the PCR test and color test kit for mycoplasm contamination can not distinguish the virus and mycoplasm?

Thanks in advance

Dear Mouton,

The direct culture test is the most sensitive and reliable test for mycoplasma's. It is FDA approved along with Hoesht staining. PCR is at the moment not FDA approved, is insensitive and therefore will give both false positives and negatives. We regularly test all our cells by direct growth, and although it takes 4 weeks to get a result, we have a level of 5% positives, which is well below the estimated 10-40% level seen commonly in other areas. We have had groups who have relied on PCR and have had problems with mycoplasma contamination. It is costly and any results obtained generally can not be published.
Again the major sources of mycoplasma infection is either the FCS or the technician/scientist.

thank you very much, could you send me your protocol and a picture showed which is negative, and which is positive if it is not problem. I heard the the staining of Hoecht, but i never try myself.
jzhang@ulb.ac.be

We also used DAPi and Hoechst, but we tried also to use PCR detection system, but as reported previously from Rhombus, they don't work very well, beacuse there are a lot of false positive and negative. In my opinion the best test in terms of precision and sensivity is which one produced by Roche, is an Elisa Test against four proteins specific for four different mycoplasma. You can find it at:
https://www.roche-applied-science.com typing "mycoplasma" in the reserach browser.
regards