Anti-Clostridium difficile Toxin A Antibody

[Toxin A]: Precursor of a cytotoxin that targets and disrupts the colonic epithelium, inducing the host inflammatory and innate immune responses and resulting in diarrhea and pseudomembranous colitis (PubMed:20844489). TcdA and TcdB constitute the main toxins that mediate the pathology of C.difficile infection, an opportunistic pathogen that colonizes the colon when the normal gut microbiome is disrupted (PubMed:19252482, PubMed:20844489). Compared to TcdB, TcdA is less virulent and less important for inducing the host inflammatory and innate immune responses (PubMed:19252482). This form constitutes the precursor of the toxin: it enters into host cells and mediates autoprocessing to release the active toxin (Glucosyltransferase TcdA) into the host cytosol (By similarity). Targets colonic epithelia by binding to some receptor, and enters host cells via clathrin-mediated endocytosis (By similarity). Binding to LDLR, as well as carbohydrates and sulfated glycosaminoglycans on host cell surface contribute to entry into cells (PubMed:1670930, PubMed:31160825, PubMed:16622409). In contrast to TcdB, Frizzled receptors FZD1, FZD2 and FZD7 do not act as host receptors in the colonic epithelium for TcdA (PubMed:27680706). Once entered into host cells, acidification in the endosome promotes the membrane insertion of the translocation region and formation of a pore, leading to translocation of the GT44 and peptidase C80 domains across the endosomal membrane (By similarity). This activates the peptidase C80 domain and autocatalytic processing, releasing the N-terminal part (Glucosyltransferase TcdA), which constitutes the active part of the toxin, in the cytosol (PubMed:17334356, PubMed:19553670, PubMed:27571750). {UniProtKB:P18177, PubMed:16622409, PubMed:1670930, PubMed:17334356, PubMed:19252482, PubMed:19553670, PubMed:20844489, PubMed:27571750, PubMed:27680706, PubMed:31160825}.; [Glucosyltransferase TcdA]: Active form of the toxin, which is released into the host cytosol following autoprocessing and inactivates small GTPases (PubMed:7775453, PubMed:24905543, PubMed:30622517, PubMed:22747490, PubMed:22267739). Acts by mediating monoglucosylation of small GTPases of the Rho family (Rac1, RhoA, RhoB, RhoC, Rap2A and Cdc42) in host cells at the conserved threonine residue located in the switch I region ('Thr-37/35'), using UDP-alpha-D-glucose as the sugar donor (PubMed:7775453, PubMed:24905543, PubMed:30622517, PubMed:22747490, PubMed:22267739). Monoglucosylation of host small GTPases completely prevents the rPubMed:22267739, PubMed:22747490, PubMed:24905543, PubMed:30622517, PubMed:7775453}.

ELISA: for detection use at 1-10ug/ml <br><br>Immunoblotting: use at 0.5-2ug/ml. <br><br>Immunofluorescence: use at 1-5ug/ml. <br><br>These are recommended concentrations. <br><br>End users should determine optimal concentrations for their applications.

Clostridium difficile is a Gram-positive anaerobic bacterium that is the major causative agent of colitis and diarrhea primarily in hospitalized patients who have undergone antibiotic therapy. Pathogenic C. difficile strains produce multiple toxins. The best characterized are Toxin A and Toxin B, both of which may produce diarrhea and inflammation in infected patients. Toxins A and B are glucosyltransferases that target and inactivate the Rho family of GTPases. C. difficile most commonly affects older adults in hospitals or in long-term care facilities. However, studies show increasing rates of C. difficile infection among people traditionally not considered high risk, such as younger and healthy individuals without a history of antibiotic use or exposure to health care facilities.