The Environmental Pathogen Mycobacterium ulcerans Grows in Amphibian Cells at Low Temperatures

Abstract

ABSTRACT Mycobacterium ulcerans , the etiological agent of Buruli ulcers, is an environmental pathogen. We cultivated it in an amphibian (XTC-2) cell line that grows at 28°C. By counting of Ziehl-Neelsen-stained mycobacteria and by quantitative PCR analysis, we found that M. ulcerans multiplies rapidly in association with XTC-2 cells. Transmission electron microscopy demonstrated the presence of intracellular M. ulcerans microorganisms. These data suggest an intracellular environmental niche, and we propose use of XTC-2 cells for isolation of M. ulcerans from environmental sources.