Insights into the toll-like receptors in sexually transmitted infections.

Toll-like receptors (TLRs) are like soldiers of an innate immune system, which protects vital biological processes against invading pathogens. TLR signalling pathways help in the removal of pathogens and mediate well-established inflammatory processes. However, these processes may also aid in the development or augmentation of an infection or an autoimmune disease. Recent studies have delineated TLR polymorphism's role in the loss of function, making hosts more resistant or vulnerable to the development of an infection. In this review, we have discussed the association of TLRs with sexually transmitted infections (STIs), especially to the pathogen-specific ligands. We have also assessed the impact on TLR downstream signalling and the maintenance of cellular homeostasis during immune responses. Besides, we have discussed the role of TLRs single nucleotide polymorphisms in various STIs. Since TLRs are known to play a part in defence mechanisms and in aiding infections therefore, a thorough understanding of TLRs structure and molecular mechanisms is required to explain how they can influence the outcome of an STI. Such a strategy may lead to the development of novel and useful immunotherapeutic approaches to control pathogen progression and prevent transmission.

Efficient production of endotoxin depleted bioactive α-hemolysin of uropathogenic Escherichia coli.

Uropathogenic E. coli (UPEC), especially associated with severe urinary tract infections (UTI) pathologies, harbors an important virulence factor known as α-hemolysin (110 kDa). Hemolytic activity of α-hemolysin (HlyA) requires modification (acylation) of two lysine residues of HlyA by HlyC, part of operon hlyCABD. Most of the previous studies had used whole operon hlyCABD and gene tolC cloning for the production of active α-hemolysin. Studies involving α-hemolysin are limited due to the cumbersome and manual method of purification for this toxin. Here, we report a simple method for production of both active and inactive recombinant α-hemolysin by cloning only hlyA and hlyC genes of operon hlyCABD. Presence of both active and inactive α-hemolysin would be advantageous for functional characterization. After translation, the yield of the purified α-hemolysin was 1 mg/200 ml. Functionality of the recombinant α-hemolysin protein was confirmed using hemolytic assay. This is the first report of the production of active and inactive recombinant α-hemolysin for functional studies.