Safety study of an antimicrobial peptide lactocin 160, produced by the vaginal Lactobacillus rhamnosus.
OBJECTIVE
To evaluate the safety of the antimicrobial peptide, lactocin 160.


METHODS
Lactocin 160, a product of vaginal probiotic Lactobacillus rhamnosus 160 was evaluated for toxicity and irritation. An in vitro human organotypic vaginal-ectocervical tissue model (EpiVaginal) was employed for the safety testing by determining the exposure time to reduce tissue viability to 50% (ET-50). Hemolytic activity of lactocin160 was tested using 8% of human erythrocyte suspension. Susceptibility of lactobacilli to lactocin160 was also studied. Rabbit vaginal irritation (RVI) model was used for an in vivo safety evaluation.


RESULTS
The ET-50 value was 17.5 hours for lactocin 160 (4.9 hours for nonoxynol 9, N9). Hemolytic activity of lactocin 160 was 8.2% (N9 caused total hemolysis). Lactobacilli resisted to high concentrations of peptide preparation. The RVI model revealed slight vaginal irritation. An average irritation index grade was evaluated as "none."


CONCLUSIONS
Lactocin 160 showed minimal irritation and has a good potential for intravaginal application.
Dover
Sara E
SE
School of Biotechnology, The Royal Institute of Technology, 100 44 Stockholm, Sweden.
Aroutcheva
Alla A
AA
Faro
S
S
Chikindas
Michael L
ML
D000282:Administration, Intravaginal; D000818:Animals; D001430:Bacteriocins / Q000633:toxicity*; D004912:Erythrocytes / Q000187:drug effects / Q000473:pathology; D005260:Female; D006461:Hemolysis; D006651:Histocytochemistry; D006801:Humans; D052201:Lacticaseibacillus rhamnosus / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D019936:Probiotics; D011817:Rabbits; D014621:Vagina / Q000187:drug effects* / Q000473:pathology
D001430:Bacteriocins; C035728:lactocin