Our current knowledge for trigger factor and food allergy intolerance is still in it infancy level. We already known that the allergic intolerance are different for groups of people. Some individuals are less resistant in developing allergy than others. Allergic sensitivity or atopic allergic disease are heritable and this means that genetic factors is playing a critical role. But the latest researches reveal that it is not merely heredity factors, environmental also have significant impact for someone to develop allergy.
Allergy trigger in the form of food allergen are mostly fallen to some certain foods like milk, egg, peanuts, fish, soya and nuts. We are curios on what is so peculiar about allergens in food? We still don’t know why only certain group of people have the ability to sensitize and developed food allergy and intolerance. We know that food hypersensitivity reaction is decreasing over time, most of them, whereas reaction caused by peanut will lasting a little bit longer compare to the former food allergens.
Scientist has a lot of homework to solve some issue in food allergy and food intolerance. Much of the issues are to answer basic mechanisms and how the allergy developed. We will learn 4 type of basic mechanism reactions to food allergy and food intolerance in our body.
IgE Mediated Responses
This responses are the easiest to diagnose among other food allergy responses because it is the most prevalent. It is only occurred when the person is already sensitized before. In allergic persons, when a food allergen is found for the first time, the adaptative reaction starts production of IgE antibodies. There is a compounds known as cytokines which regulated IgE antibodies production.
The sensitization process is happened when IgE antibodies bind to mast cells. Sensitization process happened before symptoms of allergy occurred. There is some interesting debate on how early in life an individual can be sensitized. Some would indicate that sensitization can take place when babies still in womb, and the following stage after sensitization can take place weeks or sometimes years after first sensitization. This happened when individual encounters the second food allergens again.
Non-IgE Mediated Responses
In Non IgE mediated responses, adverse reactions are the effect of an immune response other than IgE. There are possibility of involvement of other class of immunoglobulin, cell mediated immunity, and food immune complexes. Other immunoglobulin implicated are IgG antibody and their subclasses. IgG4 to particular foods are frequently discovered in those with adverse reactions to food. But it is not easy to spot it because IgG antibodies are common to exists in both persons that healthy or sick. Their presence in allergicn or non allergic individuals is explained by the immune system’s ability to produce IgG antibody.
Immunoglobulin G (IgG) is a monomeric immunoglobulin, built of two heavy chains γ and two light chains. Each IgG has two antigen binding sites. It is the most abundant immunoglobulin and is approximately equally distributed in blood and in tissue liquids, constituting 75% of serum immunoglobulins in humans.[1] IgG molecules are synthesised and secreted by plasma B cells.
IgG or Immunoglobulin is monomeric immunoglobulin type which is constructed from 2 heavy chains Y and 2 light chains. In our body, IgG is the most available immunoglobulin, distributed in body tissue liquid and blood. Plasma B Cells are the precursor for IgG molecules, it then producted and released to our body. The main responsibility of IgG antibody is in second level antibody response. IgG can tie to wide range of pathogens that enters our body such as: bacteria, fungi, virus. It then do its job by cacts, immobilize and neutralize those invader for their toxins.
Immune Complex Mediated Responses
Immune complex mediated responses are also known as hypersensitivity reactions type 3. The proteins that we ate then come across specific antibodies in the body circulation. These are known as immune complexes. It comes along that immune complex formation is essentially a normal process that occurs in the course of an immune response and allows antigen clearing. These food immune complexes contain IgE, IgG and IgA antibodies. Despite the fact that circulating immune complexes containing food antigen have been demonstrated in patients with food allergy and intolerance suffering from asthma and eczema, but there is no definitive grounds that IgE or IgG food immune complexes make the person sick.
It is widely known that individuals with atopic disease, may have more than ten times normal IgE blood level. This is also happened in individual who experienced hyper IgE syndrome. This condition, may not be a necessity for indications to happen as has been seen in asthmatics with normal IgE blood levels. Based on latest research, it revealed that IgE production is not only in the blood, but can happen locally in the nasal mucosa. This production in this area are without lymphoid tissue’s involvement.
Cell Mediated Food Allergy and Intolerance
These responses are sometimes cited to as Type IV or hypersensitivity reactions with delayed effect. This type of responses are interceded by inflammatory T cells. Some suggest that food antigen in cow’ milk are causing cell mediated immune response. There is also proficient grounds that propose of coeliac disease symptoms may be aroused by a cell mediated immune response to food allergy in gluten/gliadin. The characteristic of villous atrophy in coeliac disease symptoms is only part to T cell mediated immune response to gliadin. Even though it is shown that T cells involved in coeliac disease symptoms, there is not enough proves for suggestion that that cell mediated immune response due to gliadin’s food allergy and intolerance is the main and original cause of coeliac disease symptoms.
