Three-dimensional human skin equivalent as a tool to study Acinetobacter baumannii colonization.

Area of Science:

• Microbiology
• Infectious Diseases
• Dermatology

Background:

• Acinetobacter baumannii is a significant nosocomial pathogen capable of colonizing hospitalized patients' skin.
• Skin colonization by A. baumannii poses a risk for patient-to-patient and environmental spread, necessitating effective decolonization strategies.

Purpose of the Study:

• To investigate Acinetobacter spp. skin colonization using a 3D human epidermal model.
• To characterize bacterial adherence, biofilm formation, and host response to A. baumannii and A. junii on the skin equivalent.
• To evaluate the efficacy of chlorhexidine for decolonizing A. baumannii from the skin model.

Main Methods:

• Utilized a three-dimensional (3D), air-exposed human epidermal skin equivalent model.
• Assessed adherence and biofilm formation of A. baumannii ATCC 19606(T) and A. junii RUH2228(T).
• Evaluated the impact of bacterial colonization on keratinocyte responses and the effectiveness of chlorhexidine disinfection.

Main Results:

• Both A. baumannii and A. junii replicated on the stratum corneum for up to 72 hours without epidermal invasion.
• A. baumannii formed extensive biofilms, unlike A. junii.
• Bacterial colonization did not significantly alter keratinocyte behavior or induce a pronounced inflammatory response.
• Chlorhexidine treatment achieved complete eradication of A. baumannii from the skin model without causing damage.

Conclusions:

• The 3D skin model effectively simulates Acinetobacter spp. colonization and biofilm formation.
• A. baumannii exhibits robust biofilm formation on the stratum corneum, posing a colonization challenge.
• Chlorhexidine is a highly effective disinfectant for eradicating A. baumannii from skin surfaces.
• This 3D model serves as a valuable platform for testing novel antimicrobial and disinfectant strategies against skin colonizers.