I really care about your wonderful opinions and valuable feedback. Thank you so much

To what purpose should you want to do that? Producing antibodies in the body as treatment before/after intoxication? I very much doubt that this would work.

I would always try to prevent these things rather than trying to cure afterwards.

The food of contaminated contains mycotoxins (aflatoxin) that can accumulate in the body of human. Is it can cell recognize these toxins? by producing antibodies?

Mycotoxins are too small to produce any antibody response.

In addition, I think that mycotoxins (aflatoxin) because of their ability to resist a high- temperature that may reach 220 C.

I doubt it, mycotoxins shouldn't be consider as target for an immunitary response; they are secondary metabolites produced by fungi and one the major and most Dangerous contaminat in foodstuffs. Human beings simply haven't any enzymatic pool capable of degrading these molecules.

Personally I'd consider to increase primary prevention to avoid damage done by mycotoxins.

I am not convinced that humans lack enzymes capable of metabolizing mycotoxins as stated by Mirko Benvenuti. I see no reason why they should not have these. However their capacity or specificity might not be sufficient to protect humans for the dangerous effects of mycotoxins (in the long run)

Furthermore there is to my knowledge no relationship between immune response and (enzymatic) degradation. The molecular size of mycotoxins is simply far to small to be recognized by the immune systems as antigens.

C.A. (Kees) Kan is right. Human and mice do have enzyme (glutathione S-transferase, or GST) to metabolize Aflatoxin, such as Aflatoxin B1 (AFB1), the most frequently occurring and toxic of the aflatoxins

The attached paper is a good paper discussing the toxification and de-toxification of AFB1 in mice and human.

From the paper: "Conclusive evidence that GST-mediated conjugation of AFB1-8,9-epoxide does occur in humans comes from the structural identification of the urinary mercapturic acid metabolite in the course of chemoprevention studies in the People’s Republic of China (Wang, et al., 1999)."

To make AFB1 metabolism pathway more clear. I attached a figure from a 2017 paper (see attachment).

Figure explaination:

"Overview of AFB1 metabolism. AFB1 is metabolically activated by phase I enzymes, including cytochromes P450 CYP1A2 or CYP3A family members to the reactive AFB1 epoxide, which can damage DNA by forming the AFB1-N7-guanine covalent adduct. The main pathway to detoxify the epoxide involves the phase II enzymes GSTs, which chemically inactivate it by conjugation to GSH (Kensler et al., 2003)."

Following

Dear @Yuan-Yeu Yau

I do know aflatoxins are toxic metabolites produced by certain fungi in or on foods and feeds- & cause disease in animals, including people worldwide. By their nature, warmth and moisture are needed for them to grow. They primarily result in liver damage and immunity suppression & a few cause cancer, which, I assume is the reason for the interest in the vaccine, especially for areas people live in where it might be difficult to ensure safety in the food production, and where there is not an over abundance of such foods in the first place. The crops with highest risk of aflatoxin contamination are corn, peanuts, and cottonseed, but sometimes milk, eggs, and meat products (cheese, for instance) are bad because the livestock it came from had contaminate food. Care in the processing of foods, from crops to livestock seems to be the best and easiest way to manage the toxins, so far, but still, there are a lot of problems from them. I may have told you things you already know- very likely I expect, but I do not know your level of expertise. International Agency for Research on Cancer (IARC) might be able to provide information. I have an impression Cornell University department of animal science might possibly have people working on this.

I also think looking into vaccines for cancer prevention or treatment is definitely the way to be going at this time. The ways already prevalent are SO damaging to the victim and even family in so many ways. Dr.Georg Springer I think was one of the first doctors to look at vaccines against cancer-breast cancer was what he focused on since both his mother & wife died of it. His wife, with his treatment, lived years longer than the experts had expected she could, and without the misery & residual effects from chemotherapy and/or radiation.

Hi @ Mohammed H. Musleh,

1. Yes, but if you want to produce vaccine, first the 'substances' have to have the ability to induce 'immune response' and produce antibodies. Then, the antibodies neutrolized the antigenes. Not every substance can be antigen and induce immune response to produce antibody in animals.

2. Researchers have used genetic engineering method to eliminate aflatoxin. You mentioned that crops with highest risk of aflatoxin contamination are corn. I don't know whether you have noticed a 2017 paper published in Science about producing aflatoxin-free corn through genetic engineering. I will try to find this paper.

Ok, this is the paper I mentioned in my previous answer (in Science). Have you seen this 2017 paper?

They used RNA interference (RNAi) to inactivate the aflC gene, which encodes an enzyme in the Aspergillus aflatoxin biosynthetic pathway.

**Title: "Aflatoxin-free transgenic maize using host-induced gene silencing"

Science Advances 10 Mar 2017: Vol. 3, no. 3, e1602382 DOI: 10.1126/sciadv.1602382

Hi @ Mohammed H. Musleh,

By the way, this is definition of antigens from Wiki.

• "Antigens are usually peptides (amino acid chains), polysaccharides (chains of monosaccharides/simple sugars) or lipids. In general, saccharides and lipids (as opposed to peptides) qualify as antigens but not as immunogens since they cannot elicit an immune response on their own."
• "Furthermore, for a peptide to induce an immune response (activation of T-cells by antigen-presenting cells) it must be a large enough size, since peptides too small will also not elicit an immune response."

Dear @Yuan-Yeu Yau

RNA interference (RNAi) is a powerful tool for elucidating gene function in plants and altering gene expression for desired traits . Host-induced gene silencing (HIGS) is an RNAi-based process where small RNAs made in the plant silence genes of pests or pathogens that attack the plant. The small RNAs are generally made by producing double stranded RNA (dsRNA) in transgenic plants but for experimental purposes the dsRNA can be introduced into plant cells with agrobacterium or viruses that replicate through dsRNA. Gene silencing approaches for pest resistance in plants have only been commercialized for virus resistance to date.

but !

There are many fungal species

Aspergillus flavus

A. parasiticus

A. nomius

A. bombycis

A. Ochraceoroseus

A. australis

A. pseudotamarii

that have the ability to produce aflatoxin. How can target more than genus at the same time? If there is more than an infection?

@ Mohammed H. Musleh,

1. You mentioned that RNAi can be generated through introducing plant cells with Agrobacterium. Now, the newer technology can just spread dsRNAs direct onto the leaves to induce RNAi effect. The most recent advance even used Nanosheet to wrap dsRNAs and spread them onto plant leaves. The nanosheets are biodegradable (good for environment) and can slowly release the dsRNAs into plant leaf tissue to generate RNAi response for disease resistance. Naonsheets can also protect dsRNAs from early degradation (http://www.nature.com/articles/nplants2016207)***.

2. I am not sure whether the biosynthesis pathways of those toxins for the different fungal species you listed are conserved or the critical gene involved in those toxins' synthesis are conserved? If so, one transgenic RNAi should have the ability to provide protections for all the toxins by inactivating the conserved gene. If not, one can also genetically transform more than one RNAi DNA cassette into the plant to target different fungal species. Transfomraiton of more than 10 gene cassettes into a plant is achievalbe, and have been reported.

***Title: Clay nanosheets for topical delivery of RNAi for sustained protection against plant viruses

By the way, in the Science paper I attached earlier, it indicates that "At least 20 aflatoxins are known, but aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2) are the four found in food (18), and their biosynthetic pathway is well characterized at both the genomic and biochemical levels (19, 20)."

So, we can focus and target the biosynthetic pathways for those 4 toxins. Transformation of 4 RNAi cassettes into a plant should be not a problem. Even better, now we can use even powerful tool, such as CRISPR-Cas9 to precisely knockout the crucial enzyme genes in the pathways. Nowadays, CRISPR enzymes targeting either to a specific gene (DNA or mRNA) are avaliable.

I really care about your wonderful opinions and valuable feedback. Thank you so much