UTI patients have pre-existing antigen-specific antibody titers against UTI vaccine antigens.

UTI patients have pre-existing antigen-specific antibody titers against UTI vaccine antigens. Vaccine. 2019 Jul 15;: Authors: Sarkissian CA, Alteri CJ, Mobley HLT Abstract Urinary tract infection (UTI) is most frequently caused by uropathogenic Escherichia coli (UPEC). Our laboratory has been developing an experimental vaccine targeting four UPEC outer membrane receptors involved in iron acquisition - IreA, FyuA, IutA, and Hma - to elicit protection against UTI. These vaccine targets are all expressed in humans during UTI. In the murine model, high titers of antigen-specific serum IgG or bladder IgA correlate with protection against transurethral challenge with UPEC. Our aim was to measure levels of pre-existing serum antibodies to UTI vaccine antigens in our target population. To accomplish this, we obtained sera from 64 consenting female patients attending a clinic for symptoms of cystitis. As a control, we also collected sera from 20 healthy adult male donors with no history of UTI. Total IgG and antigen-specific IgG titers were measured by ELISA. Of the 64 female patients, 29 had significant bacteriuria (>104 cfu/ml urine) and uropathogenic E. coli (UPEC). Thirty-five patients had non-significant bacteriuria (<104 cfu/ml). Antigen-specific IgG titers did not correlate with the presence or absence of the gene encoding the antigen in the infecting strain (when present), but rather titers were proportional to prevalence of...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research