Chapter 10 1 Autoimmunity Auto self immunity against your own body a b Immune system recognizes self cell antigens Ag as foreign Ag Immune response IR results in abnormal auto antibodies auto Ab and auto reactive T cells c Type II and III hypersensitivity d 5 7 of the U S population suffer from autoimmune disorders i Women men ii Mostly in adults 20 40 years old iii Mostly chronic iv High morbidity complications and mortality 2 Autoimmunity Risk Factors idiopathic they are risk factors not etiology a Genetic genes that code for yourself i MHC HLA 1 MHC major histocompatibility complex 2 MHC 1 found on nucleated cells 3 MHC 2 found in immune cells ii Gender iii Genetic mutations b Hormonal i Viral bacterial infections ii Lifestyle Stress c Environmental 3 Autoimmune Disease Classification a Organ specific damage to a single organ Hashimoto thyroiditis b Systemic auto Ab damage multiple organ systems systemic lupus erythematosus whole body 4 Immunodeficiency Disorders Primary a Congenital born with or inherited i Present at birth ii Genetic spontaneous mutation or inherited iii Most defects are minor subclinical b Acquired i HIV AIDS c B and T Cell Combined Disorders i Severe combined immunodeficiency SCID Bubble boy completely no contact with the outside world starting at birth It is too easy for them to contract fatal infections and die d T Cell Disorders i DiGeorge syndrome missing thymus ii What to remember Catch 22 C Cardiac abnormalities A Abnormal facies T Thymic aplasia no production of thymus C Cleft lip palate H Hypocalcaemia or hyperparathyroidism 22 chromosome 22 e B Cell Disorders i IgA Deficiency most common ii Brutons Agammaglobulinema 1 no B cell production no immunoglobulins 2 Lactose intolerant 3 Mainly found in Boys 4 X linked 5 Symptoms normally present around 6 months of age f Disorders of phagocytes g Complement deficiencies 5 Immunodeficiency Disorders Secondary a Etiological factors i Physical increasing age bone marrow infiltration by tumor cells if bone marrow doesn t have the room to produce B cells then it wont ii Psychosocial depression stress iii Nutritional malnutrition mineral deficiency iv Environmental viruses splenectomy increased risk of encapsulated bacteria the spleen normally gets rid of the encapsulated bacteria v Pharmacological alcohol chemotherapies chemotoxic immunosuppressants suppress immune system prednisone corticosteroids b Usually transient i Temporary ii Can be altered c Not usually present at birth 6 Immunodeficiency Disorders HIV Induced a HIV 1 Take away depression drugs and take away immunodeficiency v Causes AIDS b AIDS i Retrovirus Reverse transcriptase as the enzyme meaning it goes backwards RNA the virus is able to incorporate into the DNA of the host so when the cell is replicated the virus is now replicated The more its replicated the more virus you are infected with ii Gains access to infect CD4 lymphocytes result in cell death iii STD iv Diagnosis HIV Ab viral load 200 CD4 cells mm3 blood Less than 200 means AIDS The higher the viral load means its getting worse and the more infected you are i Diagnosis HIV Ab viral load 200 CD4 cells mm3 blood impaired delayed hypersensitivity presence of opportunistic infection ii Therapy highly active anti retroviral therapy HAART Anti retrovirals don t eradicate the virus it just limits the amount of T Lymphocytes infected causing the survival rate to increase This prevents the patient from getting AIDS because it reduces the CD4 cells from decreasing and keeps the viral load from increasing iii Research into HIV vaccine development Research has shown that the newly developed vaccines aren t lasting long enough to help because they mutate so fast that they are no longer useful iv Pneumocystic Jirovecii sign of AIDS 7 Hypersensitivity overreaction to stimuli of our immune system a Excess I R humoral cell mediated against normally harmless Ag b Mechanism Ag Ab humoral or Ag lymphocyte T lymphocyte interaction c Classification i Type I immediate 5 min anaphylactic ii Type II cytotoxic antibody dependent iii Type III immune complex I C mediated iv Type IV delayed 24 hours cell mediated d Onset i ii Delayed Type IV IV is t cell dependent Immediate Types I II III 1 2 3 are also antibody dependent 8 Hypersensitivity Type I Immediate within 2 3 minutes after exposure to allergen a b Ab involved IgE allergies parasites asthma cancer c Cells involved mast cells basophils d Reactions allergy atopy inherited the allergy has a predisposition to it 9 Hypersensitivity Type I a Host exposed to allergen i Pollen food insect venom etc b Allergen specific IgE produced B memory cells tell the plasma cells to make IgE c in response to exposure IgE binds to and covers mast cells or basophils via Fc receptor on the cell surface i These sensitized cells can persist for weeks d Re exposure to same allergen allergen binds to Fab of IgE e Activation degranulation of mast cell or basophil f Mediators released from cells histamine 10 Hypersensitivity Type I Clinical Manifestations a Mild to life threatening b Allergic Rhinitis Nose i Most common atopic disorder in the U S ii Triggers airborne because it has to get to the nose allergens pollens molds animal dander or saliva dust mites also tobacco smoke iii Seasonal or year round iv Runny nose sneezing watery eyes v Increases risk of allergic asthma vi Look for clear watery mucous from the nose c Allergic Asthma lungs i Often occurs with allergic rhinitis ii Triggers same allergens causing rhinitis environmental pollution iii Signs exaggerated bronchial response cough wheezing shortness of 1 The release of histamine in the bronchials causes an obstruction tobacco smoke breath and wheezing d Systemic anaphylaxis i Potentially life threatening ii Triggers food shellfish peanuts drugs penicillin venom bee sting iii Signs shock airway obstruction multi system organ involvement fatal without treatment iv Treat epinephrine injection even if dehydrated give EPI first v Generalized reaction affects cardiovascular system 1 Shock Increased heart rate 2 3 Increased respiration rate 4 Decreased blood pressure vi The histamine is what caused the obstruction making you not able to breathe which usually ends in a trache 11 Hypersensitivity Type I Clinical Manifestations a Atopic Dermatitis i Triggers irritants soap detergent airborne allergen food ii Signs itchy and red skin rash slightly elevated chronic lesions with iii Complications secondary bacterial infection by