CASES/ ABSTRACTS

Submitted by Amelia Collins, University of Georgia

Evaluating host pathogen interactions of Bordetella bronchiseptica and Bordetella pertussis with respiratory epithelium utilizing an Air-Liquid-Interface system

The genus Bordetella contains many common respiratory disease-causing pathogen species in both humans and animals. Bordetella pertussis (Bp) and Bordetella bronchiseptica (Bb) cause Whooping cough in humans and Kennel cough in dogs, respectively. Bp and Bb reside in the respiratory tract and tightly adhere to epithelial cells during infection. Previous in vitro model systems used to evaluate the host-pathogen interactions occurring at this critical interface have not use polarized epithelial cells that simulate the human natural respiratory tract. This study utilizes an Air-Liquid-Interface culture system (ALI) using human broncho-tracheal (NHBE) cell cultures replete with cilia, goblet cells, mucus, and sol layers to evaluate how these pathogens interact with their niche: the ciliated epithelium that lines the mammalian airways. This study utilizes a highly virulent circulating strain of Bp (D420) and two isogenic mutant strains lacking key virulence factors (btrS and pertussis toxin) to evaluate tight junction integrity via trans-epithelial electrical resistance, bacterial growth on the apical surface, migration through the epithelium to the basal media, bacterial attachment & localization, and pro-inflammatory cytokine responses to infection. The data generated from these studies will reveal the roles of specific Bordetella virulence factors in various measurable aspects of their interactions with ciliated respiratory epithelia.