Invasion of Epithelial Cell Monolayers by Turkey Strains of Pasteurella multocida

Abstract

Two serotype 3,4:A strains of Pasteurella multocida that differ in virulence in turkeys were examined for their ability to invade epithelial cell monolayers grown in tissue culture. Both organisms were comparably adherent to cells of turkey kidney origin. However, the virulent strain (86-1913) penetrated primary turkey kidney epithelial cell monolayers at 10 times the level of the low-virulence vaccine strain. The virulent strain was also able to invade porcine epithelial cells (PK15) and feline epithelial cells (CRFK) in cell culture. Neither organism invaded rabbit epithelial cells (RK13). Invasion of turkey cells was prevented by inhibition of bacterial protein or RNA synthesis but not by pretreatment of the monolayers with periodate, trypsin, or neuraminidase. Invasion might be a mechanism of pathogenicity for this organism, contributing to colonization or virulence.

Avian pasteurellosis: Taxonomy of the organisms involved and aspects of pathogenesis

“…The effect was due to haemagglutinins associated with the capsule and not to hyaluronic acid. The significance of this for the pathogenesis of fowl cholera is difficult to evaluate as it is known that strains of P. multocida show low levels of adhesion in vitro (Lee et al, 1994;Rhoades & Rimler, 1990a). Encapsulation of toxigenic serovar D isolates from swine was shown not to improve adhesion to porcine respiratory tract cells and mucus when compared with uncapsulated variants (Jacques et al, 1993).…”

“…The relevance of these models for neuraminidase in fowl cholera seems uncertain. Since avian respiratory epithelial cells contain neuraminic acid residues (Castells et al, 1990), it has been speculated that neuraminidase could, by degeneration of the acid, expose other carbohydrate residues which could act as receptors for strains of P. multocida, thereby facilitating invasion (Lee et al, 1994). Recently, it was shown that mice passively immunized with rabbit antiserum to neuraminidase from P. multocida A:3 were protected against subsequent homologous challenge infection (Ifeanyi & Bailie, 1992).…”

Characterization, identification, and purification of the bacterial receptor expressed by turkey peripheral blood monocytes for serogroup A:3 of Pasteurella multocida

“…In turkeys, the lymphoid tissue is localized on the lower-eyelid conjunctiva and fully develops by three weeks of age. The conjunctiva-associated lymphoid tissue resembles, in many aspects, the mucosa-associated lymphoid tissues of the Pasteurella multocida adhesion to epithelial cells has received some interest (29,30,31,67,75). Studies of the HeLa cell model revealed that the capsular hyaluronic acid of serogroup A;3,4 strains off.…”

“…multocida promotes bacterial adhesion (30). Electron microscopy studies of cultured turkey kidney epithelial cells indicated that P. multocida associates with cilia, and that internalization occurs on thickened protrusions of the epithelial cell surface (75). Although the author demonstrated that internalized bacteria were not associated or enclosed in cytoplasmic organelles, the author did not examine whether or not intracellular bacteria were resistant to Many animal species exhibit age-related changes of mucosal epithelial cell surface glycoproteins.…”

“…In particular, young turkeys are less susceptible to fowl cholera than adult birds (109). It is unknown which factors are responsible for this occurrence, but age-related changes in epithelial cell receptors may be partially responsible (75). The avian respiratory epithelium is indeed extensively covered by neuraminic acid residues (sialic residues) on which neuraminidase treatment exposes other carbohydrate residues, such as mannose and galactose (20).…”