Cholera Toxin: The Two-Edged Sword
April 19, 2023 2023-04-25 6:55Cholera Toxin: The Two-Edged Sword
When we hear the term Toxin, the first thing comes to our mind is something which affects our health or a villain for us. But if I will say that a toxin can be a Hero too? Unbelievable! right?
In this article I will discuss about a toxin which has lethal effect but is considered as a very useful component in pharmaceutical industry which is Cholera Toxin.
We all know that Cholera is acute diarrheal disease which cause dehydration in the body caused by Vibrio cholerae. Cholera Toxin (CT) is the main culprit produced by V. cholerae which causes extreme water loss from the body as watery diarrhea. CT has two subunits, CTA and CTB. CTA subunit is responsible for disease expression and CTB helps in delivering CTA to the target cell. CTA1 (one subunit of CTA) enters the cell cytosol and catalyzes the ADP ribosylation of adenylate cyclase. It increases the amount of intracellular cAMP, impaired sodium uptake and chloride outflow causing extreme water secretion and diarrhea which can cause death to the patient.
Despite of having lethal effects, CTB is has strong mucosal immunogenic properties. CT has adjuvant potential when incorporated into mucosal vaccine. Some vaccines are developed against some bacterial pathogens by conjugating antigens to CTB to induce immune responses. Some research found that rCTB-UA can induce antibodies to UreA and UreB proteins, which inhibits the activity of H. pylori urease. Besides that, mucosal immunization of a female with vaccines containing CTB helps to protect their offspring from respiratory disease. CTB has been incorporated into alternative drug delivery system like microspheres and liposomes. Recent studies showed that CTB can induce anti-inflammatory response. Keeping all the benefits of CTB in Mind, scientists have developed plant based production of rCTB using transgenic technologies. Yuki and colleagues have developed transgenic rice which has rCTB expressed seed endosperm which can administrate CTB orally to induce CT holotoxin neutralizing antibodies. These are some focused area in pharmaceutical use of CT.
From the previous discussion we can conclude that Cholera toxin has both positive and negative sides like a two edged sword based on their application. Some component which is toxic to us should not be considered as bad always because it can also be a life savior if applied properly just like a villain in movies can also be a hero in his own story.
Authored by Anamika, BITS Biocon Certificate Program in Applied Industrial Microbiology, Batch 9
