Immune Mediated Diseases
The original concept of allergy included all immune-mediated disease and the
term allergy was interchangeable with the term "hypersensitivity."
One textbook of clinical immunology defined allergy: “The original definition
of allergy in 1906 was --- a specifically changed reactivity of the host to an
agent on the second or subsequent occasions. This covers a whole spectrum of
immune responses, both protective and harmful. However, more recently, the term
allergy had been restricted to type 1 hypersensitivity. This rigid definition is
too narrow to cover the range of conditions seen by allergists in clinical
practice. It is likely that all four types of hypersensitivity are involved in
various allergic diseases and indistinguishable reactions can sometimes be
produced without immunological involvement."
Delayed patterns of allergy are not obvious and generally
go unrecognized. Allergy skin tests do not show this problem. Symptom
onset is delayed hours to days after exposure to the trigger foods. Allergic
reactions to drugs such as penicillin and to foods are usually delayed
Many chronic diseases are either degenerative and/or inflammatory and many
are recognized to be immune-mediated or hypersensitivity diseases. The delayed
patterns of allergy can be the cause of chronic and disabling hypersensitivity
disease. The stakes are high both for individual patients and for the society as
a whole. None of the common hypersensitivity diseases have been solved and most
appear to rage on, afflicting increasing numbers of patients with disabling
diseases. Asthma, allergy, rheumatic diseases, autoimmune diseases, multiple
sclerosis, diabetes, thyroiditis, psoriasis are examples of hypersensitivity
diseases which involve humoral and cell-mediated immunity. We use celiac disease
- wheat allergy- as a prototype which demonstrates the prolific ability of food
allergy to produce a wide range of diseases.
Prominent allergist-immunologists such as Brennerman, Gerrard, Knicker, Hill,
Brostoff and numerous others for many years made conspicuous efforts to
elucidate the delayed forms of food allergy which involve the most profound
immune mechanisms. Unfortunately, all the good science that has been done is now
mostly ignored. Allergists for the most part act as if delayed patterns of food
allergy do not exist and physicians in other specialties have no idea about
food-related immune mediated disease. The only hope for patients is to resolve
these problems is to take charge of their own management.
Four mechanisms of immune activity
When trying to understand the wide spectrum of
hypersensitivity disorder, it is help to return to the Gell Coombs concept of 4
Type 1 or immediate hypersensitivity is IgE-mediated or common allergy.
Type 2 or cytotoxic reactions mediated by antibody, complement, and/or
cellular mechanisms. The target in type II reactions is a cell membrane and
cellular damage or death is the result.
Type 3 mechanisms involve antibodies forming immune complexes with antigen.
Circulating complexes activate complement, attach to red blood cells that are
removed by phagocytosis in the spleen, or leave the circulation and trigger
inflammation in tissue spaces (Arthus reaction), or are phagocytosed by
macrophages in tissue spaces which present antigen, release cytokines and
Type 4 are cell-mediated reactions take 12 or more hours to develop and are
based on antigen, T-cell interaction. Inflammation is the basic tissue pattern.
Allergy can be thought of as hypersensitivity disorders with external
causes. Substances that trigger allergic responses are antigens. These are often
proteins that can be found in air, food and water. Airborne antigens such as
plant pollens or house dust are well known. Other airborne antigens and food
antigens are less obvious. Airborne fungi trigger delayed hypersensitivity
diseases in the lung. New and foreign substances introduced to the body such as
drugs and herbs usually cause delayed allergic reactions.
When considering the origin of hypersensitivity diseases, food materials
should be given priority consideration since that are the biggest chunk of the
environment to get inside human bodies. If the term "food allergy" refers to all
interactions between molecules derived from the food supply and the immune
system, then many hypersensitivity disorders fall into the category of food
Prototype of Type III -IV Illness Systemic Lupus Erythematosis
(SLE) is an immune-mediated disease which serves as a model of hypersensitivity
disease. The peak incidence of SLE is in women between the ages of 20 and 40 and
who present with a typical malar rash, lymphadenopathy, arthralgias, fever,
fatigue and will often complain of recurrent flu-like illness. As the disease
advances, increased evidence of target organ damage can be found with protein
and red cells in the urine, pleurisy, pericarditis, hair loss, and circulating
auto-antibodies, especially antinuclear.