Published: 2 January 2024| Version 1 | DOI: 10.17632/mm9yrc5673.1
Ahmed Touni


Antibiotic ointments were topically applied to vitiligo-prone, pmel-1 mice, evaluating the consequences of short-term antibiotic treatment on the kinetics of depigmentation. Bacitracin, Neosporin, or Vaseline were applied to one denuded flank, while the contralateral flank was treated with Vaseline in all mice. Ventral depigmentation was quantified weekly. We found that topical Neosporin treatment significantly reduced depigmentation and exhibited effects beyond the treated area, while Bacitracin ointment had no effect. Our study highlights the therapeutic potential of short-term antibiotic applications to limit depigmentation vitiligo.


Steps to reproduce

Pmel-1 mice (Overwijk et al, 2003) received a total of six weeks of treatment comprised of three topical applications per week, applied in a series of 4 weeks on, 2 weeks off, 2 weeks on. The treatment involved shaving the dorsal right and left hand flanks of each animal, followed by application of either 100% white petrolatum (‘Vaseline’; Unilever, Trumbull, CT) (control; N = 11), Bacitracin zinc 500 U/g (‘Bacitracin’; CareAll products, Nashville, TN) (N = 10), or Bacitracin Zinc 400 U/g, Neomycin Sulfate 0.35% w/w, Polymyxin B sulfate 5000 U/g (‘Neosporin’; Johnson & Johnson CI, Skillman, NJ) (N =9). Treatments were applied to the right flank and Vaseline to the left flank to control for intra-animal variation. The ventral side was neither shaved nor directly treated. were scanned weekly to monitor depigmentation. Depigmentation was measured by flatbed scanning (Hewlett-Packard, Palo Alto, CA) under isoflurane anesthesia (EZ Systems, Palmer PA and Isoflurane, USP, Covetrus, India) essentially as described (Dellacecca et al., 2020). Briefly, luminosity was measured, and images were analyzed using Adobe Photoshop software (Adobe Systems, San Jose, CA). The percent depigmentation essentially represents a continuous measure and was calculated from the largest evaluable area as the percentage of pixels among >150,000 evaluated with a fully depigmented pelage representing 0% depigmentation and a fully depigmented pelage representing 100% depigmentation. Depigmentation was graphed over time, and the slopes were calculated and compared between the antibiotic and control treatment groups for each monitored area of the pelage.


Dermatology, Microbiome, Vitiligo