Adherence of Bordetella bronchiseptica to hamster lung fibroblasts

The adherence of Bordetella bronchiseptica smooth-, intermediate-, and rough-phase isolates to hamster lung fibroblasts (HLF) (Don line) was characterized by competitive inhibition studies and enzyme and chemical treatments of both the bacteria and the HLF. The adherence of the rough- and intermediate-phase isolates (n = 13) was altered by coincubation of the bacteria and HLF with cationic chelators, including EGTA and citrate. EGTA inhibition of the adherence of the rough- and intermediate-phase isolates could be overcome by the addition of Ca2+, Mn2+, Cd2+, or Sr2+ to the reaction mixture. In addition, citrate released bound bacteria from the HLF. Although the adherence of the smooth-phase isolates (n = 4) was unaltered by cationic chelators, binding was inhibited by N-acetylated amino sugars, with N-acetylglucosamine inhibiting 98% of the adherence of the smooth-phase isolates. Homogenization, protease K, and heat treatment (60 min, 60 degrees C) of the bacteria also resulted in a loss of adherence. It was concluded that B. bronchiseptica can adhere to HLF by at least two mechanisms and that the ligand responsible appears to be a proteinacious, heat labile cell surface component.