STUDIES OF THE PRESENCE OF THE VIRULENCE FACTORS, ADHESION, INVASION,INTRACELLULAR MULTIPLICATION AND TOXIN FORMATION IN SALMONELLAS OF DIFFERENT ORIGIN

Salmonellas of different origin were classified into two groups (11 st rains of common serovars which had been isolated from organs of calves having died from salmonellosis and 18 strains belonging to rare serov ars which showed uncommon metabolic characteristics and had been isola ted from spices and spiced foods). The strains were examined with rega rd to different virulence parameters. All salmonellas investigated pos sessed the genetic information on invasion (invA) and toxin formation (stn). They adhered equally well to epithelial cells, could penetrate into these and survive and multiply inside the cells. The formation of toxic substances could be detected in all strains after co-cultivatio n with epithelial cells in the CHO-K1 test. Significant differences be tween the groups of strains could be demonstrated only for the invasio n of epithelial cell monolayers. Since adhesion, invasion and the abil ity of intracellular survival and multiplication as well as toxin form ation constitute virulence parameters of salmonellas, it must be assum ed that also the Salmonella serotypes studied which have been rarely o bserved epidemiologically constitute a risk for humans.