Antibodies = Immunoglobulins
Antibodies are serum proteins or immunoglobulins. These proteins comprise a
memory system which detects antigens and then links antigens to an effector
system that defends against the antigen and associated structures. Antibodies
are secreted by B-lymphocytes ( transformed to plasma cells in tissue spaces).
Antibodies may be free-floating in the blood and combine with antigen to form
The sensing ends of antibodies form an antigen recognition site - the tips of
the y-shaped molecule which encode antigen recognition are known as the
hypervariable region. Antibodies also have action sites which activate
complement and/or phagocytic cells - the effector system. Antibodies attaching
to bacterial cell-surface antigens, for example, will activate complement or
attract phagocytic cells to cause bactericidal action.
B Lymphocytes originate in the bone marrow and migrate to lymphatic tissues
throughout the body. The main sites of serum antibody production are the spleen,
lymph nodes and mucosa associated lymphatic tissues. In young children, serum
immunoglobulins increase in concentration and variety as they grow, an
indication of expanding acquired immunity and hypersensitivity to a variety of
potential antigens that arrive from the environment. Infants inherit some
antibodies from their mothers, but face an onslaught of antigens that their
immune cells must learn to recognize. Estimates of the number of distinct
antibodies present in an adult human are up to a million or more.
Antibodies can be very specific to one antigen target and are used
extensively in biological research to locate and mark target molecules.
Target-specific antibodies developed from a single clone of B lymphocytes are
referred to as monoclonal antibodies. The manufacture of antibodies for research
and therapy is big business. More than 25,000 antibodies are offered to
researchers and several are used to treat human diseases. The basic technique of
production is to immunize mice with well chosen antigens and harvest B
lymphocytes from the animals. Cells making the desired antibody are then
selected and fused with long-lived cells that will live in culture media and
continually produce antibody. New methods are being developed to produce
antibodies in more efficient, less expensive ways.
There are 5 main antibody types:
IgA: circulating and secreted on all defended body surfaces, as the first
defense against invaders. Secretory (s IgA) is found in large amounts in breast
milk, saliva, and gastrointestinal secretions. IgA may be an important and
effective antibody in sites other than mucosal tissues, such as the central
nervous system. IgA inhibits the binding of micro-organisms to mucosal surfaces,
preventing entry. IgA plays a similar role in reducing antigen entry through
mucosal surfaces. sIgA deficiency is associated with increased gastrointestinal
tract permeability and increased manifestations of delayed patterns of food
IgD: surface receptors on lymphocytes.
IgE: the antibody which produces typical allergy or immediate
hypersensitivity reactions such hay fever, asthma, hives, and anaphylaxis. Its
"normal" function seems to be in anti-parasite defense. This class of
immunoglobulins is distributed throughout the body, although the cells
synthesizing IgE are predominantly found in association with mucosal tissues.
IgE attaches to mast cells and acts as a receptor to antigen. IgE-bearing cells
are found in large numbers in the neonatal GALT, which on maturation revert to
IgA and IgM synthesis. Little is known of the traffic of IgE-bearing or
IgE-producing cells. If there is traffic of IgE cells it is less extensive than
the IgG system ; IgE is not found in breast milk, and only in very low amounts
in other secretions such as saliva.
IgG is the major circulating antibody which enters tissues freely, and
participates in diverse immune events. The IgG antibodies represent a large
vocabulary of antigen recognition molecules. There are four subgroups, currently
labeled with number suffixes, (IgG1 to 4). In some mucosal tissues (e.g. mammary
glands of ruminants), the IgG1 class of immunoglobulin-producing cells
predominates. IgG ( and IgM) activate complement.
IgM: the multivalent antibody, capable of capturing and binding antigens to
form large insoluble complexes which are readily cleared from the blood. The
isohemagglutinins (anti-A, anti-B), rheumatoid factor, and antibodies to
micro-organisms are IgM. IgM levels may be elevated in patients with delayed
patterns of food allergy, and probably manifest a protective defense response.
Secretory IgA is essential to mucosal surface defenses and deficiency of this
antibody impairs antigen-exclusion mechanisms. Patients with IgA deficiency are
likely to have increased gut permeability to antigens and may show increased
evidence of delayed patterns of food allergy and diseases that are related to
type 3 and 4 mechanisms - i.e. the "autoimmune diseases". An increased incidence
of celiac disease, rheumatoid arthritis, SLE, pernicious anemia, pulmonary
hemosiderosis has been reported in IgA deficient patients. There is increased
incidence of antibodies to food antigens. The diet of patients with IgA
deficiency require adaptive revision - if symptoms develop the therapeutic
strategy is to reduce food antigen loading to compensate for increased antigen
entry. This can be done with the Alpha Nutrition Program approach to diet
revision. A complete solution to IgA deficiency disease is to replace food with
an elemental nutrient formula that provides all nutrients in the absence of