DNA Fingerprinting of Lactobacillus crispatus Strain CTV-05 by Repetitive Element Sequence-Based PCR Analysis in a Pilot Study of Vaginal Colonization

Lactobacillus crispatus is one of the predominant hydrogen peroxide (H 2 O 2 )-producing species found in the vagina and is under development as a probiotic for the treatment of bacterial vaginosis. In this study, we assessed whether DNA fingerprinting by repetitive element sequence-based PCR (rep-PCR) can be used to distinguish the capsule strain of L . crispatus (CTV-05) from other endogenous strains as well as other species of vaginal lactobacilli. Vaginal and rectal lactobacilli were identified to the species level by using whole-chromosome probe DNA hybridization. The DNAs from L . crispatus , L . jensenii , L . gasseri , and an as-yet-unnamed H 2 O 2 -negative Lactobacillus species designated 1086V were subjected to rep-PCR. The results of gel electrophoresis and ethidium bromide staining of the DNA fingerprints obtained were compared. L . crispatus CTV-05 had a unique DNA fingerprint compared to all other lactobacilli. DNA fingerprints for 27 production lots of L . crispatus sampled from 1994 through 2001 were identical to that of the original strain isolated in 1993, suggesting strain stability. In a pilot study of nine women, this DNA fingerprinting method distinguished CTV-05 from other endogenous vaginal lactobacilli prior to and after vaginal capsule use. rep-PCR DNA fingerprinting is useful for strain typing and for evaluating longitudinal loss or acquisition of vaginal lactobacilli used as probiotics.