title: Cell surface-associated aggregation-promoting factor from Lactobacillus gasseri SBT2055 facilitates host colonization and competitive exclusion of Campylobacter jejuni.
abstract: Campylobacter jejuni, one of the most common causes of gastroenteritis worldwide, is transmitted to humans through poultry. We previously reported that Lactobacillus gasseri SBT2055 (LG2055) reduced C. jejuni infection in human epithelial cells in vitro and inhibited pathogen colonization of chickens in vivo. This suggested that the LG2055 adhesion and/or co-aggregation phenotype mediated by cell-surface aggregation-promoting factors (APFs) may be important for the competitive exclusion of C. jejuni. Here, we show that cell surface-associated APF1 promoted LG2055 self-aggregation and adhesion to human epithelial cells and exhibited high affinity for the extracellular matrix component fibronectin. These effects were absent in the apf1 knockout mutant, indicating the role of APF1 in LG2055-mediated inhibition of C. jejuni in epithelial cells and chicken colonization. Similar to APF1, APF2 promoted the co-aggregation of LG2055 and C. jejuni but did not inhibit C. jejuni infection. Our data suggest a pivotal role for APF1 in mediating the interaction of LG2055 with human intestinal cells and in inhibiting C. jejuni colonization of the gastrointestinal tract. We thus provide new insight into the health-promoting effects of probiotics and mechanisms of competitive exclusion in poultry. Further research is needed to determine whether the probiotic strains reach the epithelial surface.
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Nishiyama
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Nakazato
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Ueno
authors.affiliation: Milk Science Research Institute, Megmilk Snow Brand Co. Ltd., Kawagoe, Saitama, 350-1165, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Seto
authors.affiliation: Faculty of Veterinary Medicine, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kakuda
authors.affiliation: Faculty of Veterinary Medicine, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Takai
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Animal Science, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Mukai
mesh_terms: D000818:Animals; D000898:Antibiosis; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002169:Campylobacter Infections / Q000382:microbiology / Q000517:prevention & control / Q000628:therapy; D016123:Campylobacter jejuni / Q000254:growth & development / Q000502:physiology*; D002645:Chickens / Q000382:microbiology; D004847:Epithelial Cells / Q000382:microbiology; D006801:Humans; D007422:Intestines / Q000382:microbiology; D007778:Lactobacillus / Q000737:chemistry* / Q000502:physiology*; D019936:Probiotics
chemical_list: D001426:Bacterial Proteins