State of innate immunity of mucous membranes in patients with recurrent bacterial cystitis

Uncomplicated urinary tract infections (UUTI) occur in women of reproductive age with anatomically and functionally normal bladder and urinary tract. In 25-40% of women, relapse of UUTI occurs 6-8 months after the first episode. Despite the relatively wide range of antimicrobial agents, various schemes of antimicrobial prophylaxis of recurrence of cystitis, phytotherapy, estrogen therapy, and vaccinotherapy, cystitis yet often recurs. The study was aimed to the evaluation of the components of innate immunity in the epithelial cells of the mucous membrane of the urethra in women with chronic bacterial cystitis and in healthy women at the level of gene expression of Toll-like receptors TLR2 and TLR4 and the antimicrobial peptide produced by the bladder mucosa, β-defensin-1 (HBD1). In 80% of women with chronic recurrent bacterial cystitis, significant increase in the TLR2 and TLR4 gene expression levels compared with a group of healthy donors was found, and HBD1 gene expression in urethral mucosa was reduced in all examined patients. Our study allows to understand the cause of the frequent recurrence of bacterial cystitis and identify ways for search of new drugs and drug-free modalities.

innate immunity, mucous membranes, uncomplicated infection, lower urinary tract, Toll-like receptors, antimicrobial peptides