ALLERGY GLOSSARY

ALLERGY AND IMMUNE TERMS

Adaptive Immune System A subsystem of the overall immune system the adaptive immune system, also known as the acquired immune or, more rarely, the specific immune system The overall immune system is composed of highly specialized, systemic cells and processes that eliminate or prevent pathogen growth.

Allergy: is one of the five forms of system reaction to foreign matterm known as hypersensitivities (Types 1-5). Allergies most commonly and formally called Type I (or immediate) hypersensitivity. The term was first used by Clemens von Pirquet an Austrian paediatrician in 1906 from the Greek words "allos" meaning altered and "ergia meaning reactivity. Allergy has now come to be known as a term defining altered reactivity to specific substances, which are otherwise harmless to people.

ALLERGIC REACTIONS: (See Hypersensitivity below)

ANAPHALAXIS: is a severe reaction to an allergen involving the , whole-body. After an initial exposure to a substance ( called the"sensitizing dose") the immune system becomes sensitized to that allergen. At anytime in the future a following or subsequent exposure (called the"shocking dose"), an allergic reaction will occur. This reaction is sudden, severe, and involves the whole body.The degree and severity of reaction is mediated by the immunoglobuline E (IgE) antibodies in the system (see Type 1). Even small minute amounts of an allergen, as little as a few micrograms in some cases, may cause a life-threatening anaphylactic reaction. These may as a result of any type of exposure and may occur after eating, drinking, skin contact, injection and in rare cases even inhalation, of an allergen. The severity of the response is determined in part by the number of antibodies in the system that release histamines. This in part is determined by the time since the original exposure and the severity of the original exposure. Subsequent exposures tend to get exponentially more severe and never decrease in severity. Although most people successfully avoid their allergens and will never experience anaphylaxis as much as 17% of the population is considered "at risk" for an anaphylactic reaction if they are exposed to one or more allergens and up to 1% of those who experience anaphalaxis may die. Symptoms can appear immediately, or can be delayed by half an hour to several hours after ingestion or other exposure to the shocking dose. The most common first major presentation includes sudden cardiovascular collapse as a result of the drop in blood pressure, this occurs in about 88% of reported cases of severe anaphylaxis .

ANAPHALAXIS SYMPTOMS Other symptoms of Anaphalxis include

Antibodies: (Ag) are large proteins called glycoproteins (because of the sugar attached to the amino acids ) that are found free in the bloodstream. The basic functional component of the antibody is the Y shaped protein Immunoglobuline (lg). If there is one Y shaped Ig component, the antibody is called a "monomer", if there are two Y shaped Ig proteins (such as IgA), it is called "dimeric" if there are 5 Y shaped components as in mammilian IgM it is called a "pentamer". It has been estimated that humans generate about 10 billion different antibodies, each capable of binding a distinct epitope of an antigen. Although each individual person is capable of generating a huge range of antibodies the actual number of genes available to generate the required proteins is limited by the size of the human genome, therefore several genetic mechanisms have evolved to genereate a large pool of antibodies from the limited number of genes.

Atopy: an excessive (IgE)) reaction that results in a predisposition toward developing certain allergic hypersensitivity reactions and may be related to a hereditary component.

antigen: when speaking of immunology the term which originally came from ANTIbody GENerator is the specific substance that binds specifically to the appropriate antibody B cells.

B cells: are immune system cells formed in the mammal bone marrow and circulate in both the blood and lymphatic system perfoming the role of surveillance. The B cells do not produce antibodies until they become activated. Each B cell has a unique recepter protien. A typical human B cell will have 50,000 to 100,000 antibodies bound to its surface.

Gonorrhea: , The sexually transmitted infectious disease first observed in France when the crusaders returned after they had lay siege to Acre and originally called the "french disease" . This was followed by a similar law in 1256 in France during the reign of Louis IX. . After the Pope Boniface secularized the practice of medicine, the doctors began to treat common men as well as prostitutes for this infection

In the 19th century gonorrhea was treated with the help of silver nitrate. Silver nitrate was soon discontinued and instead protargol was used which was a type of colloidal silver sold by Bayer from the year 1887.

Humoral Immune System the main function of this system is to produce antibodies each antibody recognizes a unique part of the foreign target, called an antigen .Since antibodies exist freely in the bloodstream, they are said to be part of the humoral immune system .

called

Hypersensitivity an abnormal or atypical local or systemic response that is an exaggerated, inappropriate or altered reaction by the body's immune system, in response to exposure or stimulus. The stimulus or exposure is percieved by the organism to be a foreign agent. Also called ALERGIC REACTIONS the resulting Hypersensitive Reactions are classified as one of following five types IV types (TYPE 1 - immediate, TYPE II - antibody mediated, TYPE III- Immune-compex mediated, TYPE IV - T-cell-Mediated.)

see the individual Sensitivity Reactions for more information

reactivity which results in which the body responds with an altered exaggerated and inappropriate reaction to a foreign agent by the immune system; There are several forms of hypersensitivity, of which Anaphylaxis and Allergy are but two. forms of hypersensitivity. The hypersensitivity states and resulting hypersensitivity reactions are usually subclassified by the origin and nature of the reaction:

contact Hypersensitiivity

Delayed Hypersensitivity

Immediate Hypersensitivity sified by the Gell and Coombs classification. adj., adj hypersen´sitive.

http://medical-dictionary.thefreedictionary.com/hypersensitivity

Idiopathic: when refering to a disease or condition the term means the cause or the symptoms are inconsistent and not well defined.

Immunoglobulines (Ig) are sometimes referred to as an antibodies but Ig is the just the Y shaped functional component of the Antibody. Y-shaped protein. They are produced by B-cells in the Humoral Immune System and are used by to identify and neutralize the pathogens.

Inflammation: refers to the redenning swelling and the raise in temperature of tissue and is not a synonym for infection even if infection is the primary cause. Inflammations is one of the innate immune systems first response mechanisms to harmful stimuli such as infection or irritation to a pathogen. It is considered part of the general initial acute response to harmful stimuli by increasing the movement of plasma and leukocytes from the blood to injured tissues and promotes the healing of damaged tissue and the clearance of the pathenogens. Chronic and long term inflammation can result in a number of diseases hay fever, periodontitis aathersclerosis, rheumatioid arthritis even cancer and must be closely regulated.

innate leukocytes are the cells that function within the immune system (WHICH SYSTEM???) by identifying and eliminating pathogens that might cause infection and include: Natural killer cells, mast cells, eosinophils, basophils, phagocytic cells macrophages, neutophils and dendritics cells.

lymphocytes Three distinct types of cells found in the white blood cells. Lymphocytes are B-cells T-cells and NK-cells found in the humoral branch of the adaptive immune system.

Natural Antibodies: antibodies that are produced and present in the serum of humans and higher primates, without and previous to any infectious exposure to viral, bacterial, foreign antigens or exposure to other infection by vaccination, or passive immunization. These antibodies can activate the classical complement pathway leading to lysis of enveloped virus particles long before the adaptive immune response is activated. Many natural antibodies are directed against the disaccharide galactose α(1,3)-galactose (α-Gal), which is found as a terminal sugar on glycosylated cell surface proteins, and generated in response to production of this sugar by bacteria contained in the human gut. [ 27 ] Rejection of xenotransplantated organs is thought to be, in part, the result of natural antibodies circulating in the serum of the recipient binding to α-Gal antigens expressed on the donor tissue. [ 28 ]

NKT Natural killer T-cells bridge the adaptive and innate immune systems and unlike conventional T cells recognize

special molecule types and once activated, these cells can perform functions ascribed to both T h and T c cells. NKT cells

are also able to recognize and eliminate some tumor cells and cells infected with herpes viruses.

Pathogens foreign micro-organisms that can produce or infect disease in a living organism and includes a virus, bacterium, prion, fungus, viroid, or parasite that causes disease in its host including other micro-organisms.

White blood cells are a vital part of the immune system and contain cells of both the non specific and specific immune systems. The cells that are part of the the non specific innate immune system are called innate leucocytes . The cells of the specific or adaptive immune system which are a specialized subclass of leucocytes and contain cells groups called lymphocyes and are more common to the lymph system.

T cells: a type of lymphocyte cell (see lymphocyte) in the immune system that acquired their name because they mature in the thymus. Also known as T-lymphocytes) there are several subsets of T cells, each with a specific and distinct function characterized by the receptor on the surface of the cell called a T -cell Receptor (TCR) The T-cells include :

T C Cytotoxic T cells (or CTLs) destroy virally infected cells and tumor cells, and are implicated in transplant rejection

T reg Regulatory T cells (formerly known as suppressor T cells ) are crucial in maintaining immunological tolerance

T h Cytoto?? T cells

plasma cells that secrete soluble antibody or memory cells that survive in the body for years afterward in order to allow the immune system to remember an antigen and respond faster upon future exposures.

passive immunization .

Domain variability

The region (locus) of a chromosome that encodes an antibody is large and contains several distinct genes for each domain of the antibody—the locus containing heavy chain genes ( IGH@ ) is found on chromosome 14 , and the loci containing lambda and kappa light chain genes ( IGL@ and IGK@ ) are found on chromosomes 22 and 2 in humans. One of these domains is called the variable domain, which is present in each heavy and light chain of every antibody, but can differ in different antibodies generated from distinct B cells. Differences, between the variable domains, are located on three loops known as hypervariable regions (HV-1, HV-2 and HV-3) or complementarity determining regions (CDR1, CDR2 and CDR3). CDRs are supported within the variable domains by conserved framework regions. The heavy chain locus contains about 65 different variable domain genes that all differ in their CDRs. Combining these genes with an array of genes for other domains of the antibody generates a large cavalry of antibodies with a high degree of variability. This combination is called V(D)J recombination discussed below. [ 32 ]

Elevations in different classes of immunoglobulins are sometimes useful in determining the cause of liver damage in patients for whom the diagnosis is unclear. [ 6 ] For example, elevated IgA indicates alcoholic cirrhosis , elevated IgM indicates viral hepatitis and primary biliary cirrhosis , while IgG is elevated in viral hepatitis, autoimmune hepatitis and cirrhosis. Autoimmune disorders can often be traced to antibodies that bind the body's own epitopes ; many can be detected through blood tests .

Targeted monoclonal antibody therapy is employed to treat diseases such as rheumatoid arthritis , [ 49 ] multiple sclerosis , [ 50 ] psoriasis , [ 51 ] and many forms of cancer including non-Hodgkin's lymphoma , [ 52 ] colorectal cancer , head and neck cancer and breast cancer . [ 53 ] Some immune deficiencies, such as X-linked agammaglobulinemia and hypogammaglobulinemia , result in partial or complete lack of antibodies. [ 54 ] These diseases are often treated by inducing a short term form of immunity called passive immunity . Passive immunity is achieved through the transfer of ready-made antibodies in the form of human or animal serum , pooled immunoglobulin or monoclonal antibodies, into the affected individual. [ 55 ]

Rhesus factor , also known as Rhesus D (RhD) antigen, is an antigen found on red blood cells ; individuals that are Rhesus-positive (Rh+) have this antigen on their red blood cells and individuals that are Rhesus-negative (Rh–) do not. During normal childbirth , delivery trauma or complications during pregnancy, blood from a fetus can enter the mother's system. In the case of an Rh-incompatible mother and child, consequential blood mixing may sensitize an Rh- mother to the Rh antigen on the blood cells of the Rh+ child, putting the remainder of the pregnancy , and any subsequent pregnancies, at risk for hemolytic disease of the newborn . [ 56 ]

18 One reason not to get pierced: According to the Mayo Clinic, jewelry containing nickel can trigger a lifelong metal allergy

Aquagenic urticaria is a rash caused by contact with water. It is exceedingly rare. Still, if your child claims he’s allergic to baths, he just might not be lying.

With our living environment well scrubbed of germs, our body’s immune “soldiers” mistakenly fire on innocent peanuts and cat dander.

"Perhaps the earliest report of allergic disease is that of King Menses of Egypt, who was killed by the sting of a wasp at some time between 3640 and 3300 BC. Another report from ancient history is that of Britannicus, the son of the Roman Emperor Claudius. He was allergic to horses and "would develop a rash and his eyes swelled to the extent that he could not see where he was going". Accordingly, the honour of riding at the head of the young patricians fell to Nero who was Claudius’s adopted son. Nero allegedly threw Christians to the lions and killed Britannicus. Sir Thomas More gives the next authoritative account of allergy: King Richard III used his allergy to strawberries to good effect in arranging the judicial murder of Lord William Hastings. The King surreptitiously ate some strawberries just prior to giving an audience to Hastings and promptly developed acute urticaria. He then accused Hastings of putting a curse on him, an action that demanded the head of Hastings on a plate.

"Professor Charles Robert Richet, Nobel Prize Winner for Medicine and Physiology in 1913, for the discovery of anaphylaxis. With his versatile personality he was involved in many different fields. His investigative work included diverse themes such as respiration, digestion, epilepsy and the regulation of body heat. To him we owe three new words, and as such, three new concepts: anaphylaxis, polypnea and zoomotherapy."

"Descriptions of apparent allergic reactions to natural rubber appeared in the medical literature in 1927, and irritant and delayed-contact reactions were reported in 1933. Although irritant and delayed-contact reactions to rubber products were increasingly recognized, immediate-type allergic reactions were not reported again until 1979. However, after 1980, increasing numbers of contact urticarial reactions to latex were reported, and investigations suggested that many of these reactions were IgE-mediated.

Aquagenic urticaria is a rash caused by contact with water. It is exceedingly rare. Still, if your child claims he’s allergic to baths, he just might not be lying.

With our living environment well scrubbed of germs, our body’s immune “soldiers” mistakenly fire on innocent peanuts and cat dander.

Autoimmune progesterone dermatitis

What is autoimmune progesterone dermatitis?

Autoimmune progesterone dermatitis (APD) is a rare skin condition in women that recurs in a cyclical manner corresponding to their menstrual cycles. It is thought to be a response of the skin to the hormonal changes that happen just before menses.

Characteristically, the skin eruptions occur during the luteal phase or the late pre-menstrual phase of the cycle. This is when the blood level of the sex-hormone progesterone rises. The skin rash happens as an autoimmune response to the body's own progesterone, hence its name.

Within a few days of menstruation when progesterone level falls, there is partial to complete resolution of the rash. It will recur during the next cycle.

Some patients have had previous exposure to external progesterone in the form of oral contraceptive pills. This is thought to pre-sensitize patients to react against their own internal progesterone. However, not all patients with APD are exposed to previous hormone therapy. It has been postulated that these patients produce an altered form of progesterone that incites an immunologic response against it. In another theory, progesterone is thought to heighten a patient's hypersensitivity response to another allergen.

How does progesterone dermatitis present?

A variety of rashes has been described. The most common are urticaria and erythema multiforme . Other presentations include:

Papulovesicles ( eczema -like)

Annular erythema

Angioedema

Mouth erosions (stomatitis and aphthous ulcers )

Itch (the most common complaint)

Several other skin conditions may be more severe during the perimenstrual period, but these are not classified as autoimmune progesterone dermatitis. These include:

Herpes simplex infection (cold sores)

Acne and seborrhoea

Rosacea

Atopic dermatitis

Contact allergy to nickel

Lupus erythematosus

Psoriasis

On average, the skin rash happens 7 days before onset of menstruation and lasts for 1-3 days after menstruation.

The age of onset is variable, the youngest case occurred at menarche and the disease can begin as late as 48 years of age.

Autoimmune progesterone dermatitis

Image provided by Sharon Morton

Autoimmune progesterone dermatitis