ADHESIVENESS OF BACTEROIDES-FRAGILIS STRAINS ISOLATED FROM FECES OF HEALTHY DONORS, ABSCESSES, AND BLOOD

Bacteroides fragilis strains attached to oral epithelial cells (ECs) a nd the cell line Intestine 407 and associated with human phagocytes wi th different efficiencies depending on their source. The 58%, 75%, and 40% of strains isolated from feces, abscesses, and blood respectively adhered to ECs with good efficiency (11-40 bacteria/cell). Of the str ains from feces and abscesses, 17% and 20% exhibited a high adherence (>40 bacteria/cell); however, none of the blood isolates presented thi s property. Similar results were obtained with the cell line Intestine 407 and human phagocytes. Of the isolates from feces, abscesses, and blood, 20%, 56%, and 71% respectively also exhibited hemagglutination ability, indicating that this property is a virulence trait more frequ ently present among pathogenic isolates than in commensal strains.