The Attachment to, and Invasion of HeLa Cells by Salmonella typhimurium: The Contribution of Mannose-sensitive and Mannoseresistant Haemagglutinating Activities

Abstract

The association of the haemagglutinating activities of Salmonella typhimurium cultures with bacterial adhesion to HeLa cells, and the internalization of the bacteria by HeLa cells, was studied. Adhesion was not inhibited by alpha-methyl-D-mannoside (i.e. adhesion was mannose-resistant), and only four of the six strains tested produced type 1 fimbriae and the associated mannose-sensitive haemagglutinin (MSHA). The other two strains belonged to the non-fimbriate FIRN biogroup. Cultures of all six strains contained a mannose-resistant haemagglutinating (MRHA) activity when grown at 37 degrees C, but cultures of only one fimbriate and one non-fimbriate strain did so when grown at 18 degrees C. From the comparison of cultures grown at 18 degrees C and 37 degrees C, and of mutant strains with the phenotypes MRHA-negative/MSHA-positive, or MRHA-positive/MSHA-negative, it was concluded that the MRHA activity was responsible for the attachment of salmonellae to HeLa cells. Only bacterial adhesion that was resistant to mannose resulted in the internalization of the bacteria by the HeLa cells.

Hemagglutinating properties of Salmonella enterica serovar Enteritidis isolated from different sources

“…Strains grown at 16ºC showed decreased mannose-sensitive hemagglutination compared with those grown at 37ºC (Table 1). These results agree with previous reports on the expression of Salmonella hemagglutinins (7,14,24,31).…”

“…Nonfimbrial soluble hemagglutinins have been described in Salmonella spp. (14,19,26), but they are mannoseresistant and hence different from the mannose-sensitive hemagglutinin identified here.…”

Molecular analysis of spv virulence genes of the salmonella virulence plasmids

“…Many virulence functions are encoded on the salmonella chromosome. These include: adherence to (Jones and Richardson, 1981), invasion into (Galan and Curtiss, 1989), and transcytosis through (Finlay et al, 1988) mammalian epithelial cells, which is believed to simulate infection of the gut; PhoP-regulated resistance to phagocytic defences important in lymphoid tissues (Miller et al, 1990;Fields et al, 1989); and smooth lipopolysaccharide (LPS) necessary for resistance to complement-mediated bacteriolysis in blood (Joiner, 1988).…”

Type 1 Pili Enhance the Invasion of Salmonella braenderup and Salmonella typhimurium to HeLa Cells

“…As for the genetic factors determining the pathogenicity of Salmonella, several investigators reported that serovar-specific large plasmids of Salmonella spp. are involved in systemic Salmonella infections (9,11,13). However, we recently reported that plasmids of S. braenderup and S. typhimurium are not involved in human acute enterocolitis (8).…”