Detection and antibiotic treatment of Mycoplasma arginini contamination in a mouse epithelial cell line restore normal cell physiology.

Mycoplasma contamination of cultured cell lines is difficult to detect by routine observation. Infected cells can display normal morphology and the slow growth rate of mycoplasma can delay detection for extended periods of time, compromising experimental results. Positive identification of mycoplasma typically requires cells to be either fixed and stained for DNA or processed with PCR. We present a method to detect mycoplasma using live-cell optical microscopy typically used for routine observation of cell cultures. Images of untreated mycoplasma-infected epithelial cells alongside images of infected cells treated with Plasmocin, a commercially available antibiotic targeted to mycoplasma, are shown. We found that optical imaging is an effective screening tool for detection of mycoplasma contamination. Importantly, we found that cells regained normal function after the contamination was cleared. In conclusion, we present a technique to diagnose probable mycoplasma infections in live cultures without fixation, resulting in faster response times and decreased loss of cell material.