Comparison of pulsed field gel electrophoresis karyotypes of Pneumocystis carinii derived from rat lung, cell culture, and ferret lung.

Pulsed field gel electrophoretic karyotypes of Pneumocystis carinii derived from three sources were compared: immunosuppressed virus-free rats transtracheally inoculated with Pneumocystis-infected rat lung; WI-38 cell/Cytodex bead cell cultures inoculated with the same material; and immunosuppressed ferrets which reactivated latent Pneumocystis pneumonia. Karyotypes of DNA from Pneumocystis trophozoites or cysts from rat lung, and trophozoites from cell culture were identical. In contrast, ferret Pneumocystis DNA karyotypes were distinctly different. Rat Pneumocystis gene probes reacted with Southern- transferred rat Pneumocystis DNA but not with ferret Pneumocystis DNA. We concluded that neither the source nor life stage of rat Pneumocystis carinii influenced genomic karyotype, and that rat and ferret Pneumocystis are genetically diverse.