Response of human T cells to tetanus neurotoxin HCC Sub-Domain: T cell cytokine production and activation marker induced by HCC(Article)

Abstract

Tetanus is caused by the tetanus neurotoxin (TeNT), a 150 kDa single polypeptide molecule which is cleaved into active two-chain molecules composed of a 50 kDa N-terminal light (L) and a 100 kDa C-terminal heavy (H) chains. Fragment C is further subdivided into two subdomains: the proximal H<inf>CN</inf> subdomain and the extreme carboxy subdomain, H<inf>CC</inf>. H<inf>CC</inf> is considered as an immunodominant part of TeNT and is responsible for TeNT binding activity to neurons. In the present study, we investigated the ability of recombinant H<inf>CC</inf>(r H<inf>CC</inf>) to induce T cell activation. Our results showed that recombinant H<inf>CC</inf> has a stimulatory effect on IFN-? secretion by T cells after 48h co-incubation in the presence of anti-TLR-2 Ab. Also, Hcc can induce the expression of CD69 on T cells. Our finding indicated that stimulatory effects of H<inf>CC</inf> on T cells are TLR-2 independent and anti-TLR-2 inhibitory antibody fails to neutralize H<inf>CC</inf> stimulatory effects on T cells. Furthermore, H<inf>CC</inf> is critical for immunogenic activity of TeNT and is able to induce T cells through TLR-2 independent pathway. Copyright é Autumn 2015, Iran J Allergy Asthma Immunol. All rights reserved.