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1. Autoimmune disease

2. Introduction Autoimmune disease is a condition which is triggered by immune system initiating an attack on self molecule due to deterioration of immunological tolerance to auto-reactive immune cell Since the body cannot differentiate between self antigen and non-self antigen there may be activation of, and invasion by, T cell or increased production of autoantibodies The initiation of attack against body self molecule in autoimmune disease, in most cases is unknown but number of studies suggest that they are strongly associated with factors such as genetics, infection, environment and chemical exposure play as contributors to changes in self reactivity There are various symptoms and disorders which are encompassed in autoimmune diseases, they vary from organ specific to systemic, and include, insulin dependent diabetes mellitus, rheumatoid arthritis etc.

3. Cont… Autoimmune diseases are pathophysiological states that result from a loss of self-tolerance and the consequent immune destruction of host tissues. The most common areas in the body which are targeted by autoimmune diseases are the thyroid gland, stomach, adrenal glands and pancreas. Autoimmune diseases are pathological conditions identified by abnormal autoimmune responses and characterized by autoantibodies and T-cell responses to self-molecules by immune system reactivity

4. Low level autoimmunity Autoimmunity is defined as the development of immune system reactivity in the form of auto-antibodies and T-cell responses to self-structures Autoimmunity is a necessary process of the immune regulatory networks in the body which need to sustain the body’s health. Low level autoimmunity is when the body release autoantibodies in low amount, this often lead to activation of antibodies fighting against antigen Low level of autoimmune level though it can be dangerous it is often beneficiary since it activate other antibodies into action It is yet unknown fully why autoimmunity sometimes progresses to pathologic states which are generally characterized by tissue destruction, mediated by humoral cellular self-reactive progression.

5. Immunological tolerance Immune tolerance is defined as specific non-reactivity of the immune system to a particular antigen, which is capable under other circumstances of inducing an immune response. It is caused by destruction of lymphocyte that express receptors to auto antigen as they develop, failure of this mechanism may results in autoimmune disease The administration of antigens either at high or low dose and infection with certain viruses during critical early stages of immunological development may also aid in inducing tolerance Immunological tolerance is caused by autoimmunity, this leaves the body more vulnerable to other antigen since it become tolerance of it and not fight it Immune tolerance makes the body produce immature lymphocytes that cannot fight of antigen though some may be able to Three mechanism of tolerance induction include clonal deletion, clonal ignorance and anti-idiotypic antibody

6. Immunodeficiency and autoimmunity Immunodeficiency and autoimmune phenomena may occur concomitantly in the same individual. Persistent antigen stimulation, due to an inherently defective immune system ability to eradicate pathogenesis is the primary cause leading to autoimmunity in patients with primary immunodeficiency states. Many immune deficiency syndromes, mainly humoral defects, are associated with autoimmune disorders. Patient who have autoimmune disease and have immunodeficiency are more likely to be attack by other disease since the immune system is weak Immunodeficient patient with autoimmune disease cannot be easily helped since it may need the immune system to be supressed which can be dangerous to them

7. Factors affecting autoimmune diseases People of all genders, races, and ages can be affected by autoimmune diseases, but some people are at larger risk of developing an autoimmune disease. An individual’s chance of developing an autoimmune disease is elevated if the following factors are present: Gender It is a known fact that women are at higher risk of developing autoimmune diseases, since they tend to affect women about 75% more than men. It is not entirely clear why women are more vulnerable to autoimmunity, although some researchers speculate that women's enhanced immune systems and specific hormones may make them more subject to autoimmune diseases Environmental Factors Environmental factors may have various roles in promoting, causing or modifying autoimmune diseases.

8. Cont… Environmental factors are one of the most important initiators determining the time and type of autoimmune disease when one is manifested. The type of disease in an individual, in an autoimmune prone family, can be determined by a specific combination of various infectious agents, chemicals, drugs and even vaccines. Toxic Metal Exposure - A predicted 25% of individuals have some form of heavy metal poisoning. Studies have shown that exposure to toxic metals such as mercury, cadmium, lead, arsenic, aluminium, nickel and other heavy metals can be linked to the autoimmune process as the heavy metals stimulate autoantibodies, which in turn, may result in autoimmune diseases. Toxic Chemical Exposure - Toxins such as pesticides, solvents, industrial chemicals, some household cleaners and hair dyes can be linked to autoimmune diseases.

9. Cont… Vaccinations/Immunizations - Scientists have found a connection between some autoimmune diseases and certain vaccinations. In the February 2000 issue of Autoimmunity, ten research articles evaluate the causal link between vaccinations and autoimmune disease. In one of these articles, the contentious anthrax vaccine has been causally linked to the development of certain autoimmune diseases Genetic factors Numerous studies have shown that the tendency to develop autoimmune disorders can be genetic. If a family has members who have an autoimmune disorder, others within that family have increased chances of getting the same disorder or one that is closely related.

10. Pathogenesis of autoimmunity Autoimmune diseases are avast array of organ-specific as well as systemic diseases, whose pathogenesis stems from the activation of bursa-derived (B) and thymus-derived (T) lymphocytes reacting against antigens of the body’s own tissues T cell bypass Normally, B cells are activated by T cells before B cells can produce antibodies in large quantities. However, if the T cells are bypassed and the antigen directly stimulates the B cells, the immune response may be altered Aberrant B cell receptor-mediated feedback Altered B cell receptor-mediated feedback may give rise to spontaneous autoimmunity.

11. Cont… When an antibody binds to a certain antigen, it may cause aberrent signals to be fed back to B cells through ligands bound to the membrane, such as the B cell receptor, IgGFc receptors, CD21 and toll-like receptors 9 and 7. This forms the basis of the idea that self-perpetuating self reactive B cells can exist. Molecular mimicry Structural similarities shared between an exogenous antigen and certain self antigens may result in any antibody produced against the exogenous antigen also binding to the host antigen to flag it up for attack by the immune system. This is thought to be the underlying cause of rheumatic fever, although the exogenous antigen has not yet been formally identified.

12. Classification of autoimmune disease They are two ways to classify autoimmune disease One is by the effector mechanism or the underlying initiator The other is by organ or organ system In the autoimmune disease classified by the effector mechanism, the initiation of damage is either an antibody or T cell mechanism for example in type 1 diabetes In the second classification of autoimmune disease, the disease are characterized by damage to a single organ Systemic autoimmune diseases most commonly include the skin, joints and muscle tissue

13. Cont… Systemic disorders Systemic disorders involve autoantibodies that are not specific to antigens found on certain tissues. Examples include: Systemic lupus erythematosus (SLE) Goodpasture’s syndrome Sarcoidosis Scleroderma Rheumatoid arthritis Dermatomyositis Local disorders Examples of local disorders that are specific to a particular tissue or organ can be divided into the following groups: Dermatologic diseases e.g. Scleroderma Endocrinologic diseases e.g. Addison’s diseases Neurologic diseases e.g. Multiple sclerosis Hematologic diseases e.g. Hemolytic anaemia Gastrointestinal diseases e.g. Celiac disease

14. Diagnosis A diagnosis of autoimmunity may be suspected based on a patient’s symptoms, blood test results and details of their family history. The immune system usually produces antibodies in response to the presence of harmful substances in the body such as certain chemicals, bacteria and viruses. In the case of autoimmunity however, the body produces antibodies against its own tissues and cells. These antibodies are referred to as autoantibodies and the cells and tissues that trigger their production are called self-antigens. Diagnosis of an autoimmune disease involves tests to identify whether these autoantibodies are being produced by the body. Other blood markers that indicate increased immune activity are also checked.

15. Cont… Antinuclear antibody tests – This tests for a type of autoantibody that targets the cell nuclei Autoantibody tests – These tests are performed to check for autoantibodies produced against the body’s own tissues Complete blood count – The number of red and white blood cells is checked to see whether the immune system is actively fighting disease C-reactive protein – This protein is raised when inflammation is occurring in the body Erythrocyte sedimentation rate – This acts as another inflammatory marker

16. Treatment Autoimmune diseases are chronic conditions that cannot be cured and treatment is aimed at controlling the body’s autoimmune processes, alleviating symptoms and maintaining the patient’s ability to fight disease. Depending on the patient’s type of disease and symptoms, following measure can be taken: A healthy diet and exercise Vitamin supplementation Hormone replacement therapy Blood transfusion Pain relief medication Many patients take medication to reduce the body’s immune response and these agents are referred to as immunosuppressive drugs.

17. Nutrition and autoimmunity Nutrition and autoimmune disease has been linked together for centuries now Numerous systemic studies have confirmed that nutrition deficiency can alter immune response Dietary factors are major regulators of the immune function and possibly modulate autoimmunity Vitamin D and A are potent immunomodulators and may influence the phenotype of autoimmune diseases Omega 3polyunsaturatedfattyacid may have preventive effect in rheumatoid arthritis Low dose of probiotics are effective in inflammation bowel disease while data in autoimmunity models are promising

18. Conclusion Researchers have found that they are possibly multiple “autoimmunity genes” which increase the risk of developing an autoimmune disease therefore its one best interest to do gene testing to check chances of them developing Autoimmune disease so that it can be manage well before it can start to manifest Through autoimmune disease cannot be treated its important that people with such disease exercise, eat health ad must be given intensive

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20. Reference Alarcon- Riquelme , M., Alarcon-Segovia, D. 2005. Autoimmunity. Shared Autoimmunity: The concept and introduction. 38(3): 199. Autoimmunity and Autoimmune Diseases such as Systemic Lupus Erythematosus. 2004. H. Amital , Y. Shoenfeld . Page 8. Journal of Autoimmunity Innate immunity in systemic lupus erythematosus: Sensing endogenous nucleic acids. (35) 2010. Pg. 321. E. Kontaki , D.T. Boumpas