Chemoattractive factors from Escherichia coli: individual strain variation.

Thirty-five different Escherichia coli strains isolated from patients with asymptomatic bacteriuria, cystitis, or pyelonephritis were investigated regarding their capacity to stimulate leukocyte chemotaxis in vitro. There were significant differences between individual strains in degree of chemoattraction, as well as among individual leukocyte donors in their reactions to the same strains. These differences were not correlated to specific E. coli antibodies. No significant differences in chemoattraction were found among strains isolated from patients with asymptomatic bacteriuria, cystitis, or pyelonephritis. It was suggested that the production of chemoattractive factors was not important for the pathogenicity of different E. coli strains in relation to urinary tract infection.