Term
| Four types of Immune response |
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Definition
B-cell
• Type I. Anaphylactic/atopic mechanism (Immediate) • Type II. Opsonization/Cellular dysfunction mechanism (Antibody mediated) • Type III. Immune-complex mechanism (Immune complex mediated) Hypersensitivity reactions II & III) are considered humoral immunity
T-Cell
Type IV. Delayed hypersensitivity mechanism (Cell mediated) |
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Term
| Systemic Lupus Erythematosis (SLE) |
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Definition
| • 10 females for every male affected--estrogen seems to accelerate SLE. Unit F –Icardi –page 7 • Most common in child-bearing years; children and elderly adults only occasionally affected. • Familial predisposition is evident, linked to certain HLA types, especially DR2 and DR3. • Congenital deficiency of C2 and C4 complement promotes SLE development• U.S. prevalence is ~ 1/2000 |
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Term
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Definition
| • Skin manifestations only • Usually on the face and scalp • Red scaly plaques • Systemic manifestations are rare (5-10%) • DS/native DNA negative |
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Term
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Definition
| • Intermediate between skin localized and regular systemic lupus • Widespread skin rash but also have mild systemic symptoms • Associated with anti-SSA and HLA-DR3 genotype |
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Term
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Definition
| • A lupus like syndrome caused by drugs which induce ANA formation • (e.g. Procainamide, hydralazine, isoniazid, Penicillamine) • Typically patients do not exhibit CNS or renal manifestations, unlike normal lupus • Anti-DS-DNA antibody negative • Anti-histone antibody positive • Patients with HLA-DR4 are more susceptible follow hydralazine administration • Symptoms subside with cessation of medication |
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Term
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Definition
Therapy
•Change behavior to reduce stress, and avoid sun
•Immunosuppressives as necessary to control renal, cutaneous, and other symptoms
•Corticosteroids
•Cytoxan
•6-mercaptopurine All have long and short-term side effects Five year survival is now ~ 80%.
•Imunosuppressive toxicity (BM aplasia, secondary neoplasms, infectious diseases) can cause death
•Renal failure
•Others are less common |
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Term
| Rheumatoid Arthritis (RA) |
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Definition
• Affects approximately 1-3% of U.S. adults • Female incidence 3X greater than male. • Most patients between 35 –50 yrs old • Typically involves 2-3 symmetric joints • Pain, particularly in the morning • Stiffness • Swelling • Inflammation • Generalized immune symptoms
•Malaise, fever, fatigue, loss of appetite, weight loss, myalgias, weakness • Long duration: > 6months • Symmetrical deforming arthritis which affects multiple joints; especially hands & wrists • Disease is of variable severity; severe cases often have systemic symptoms• Pediatric or “Juvenile RA” less common but more severe than adult form |
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Term
| Rheumatoid ArthritisEtiology and Pathogenesis• |
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Definition
Initiating events are unknown
•Infiltrating leukocytes and inflamed synovial cells secrete TNFα (tumor necrosis factor), causing inflammation of joint cartilage and bone and sets up a positive feedback loop perpetuating joint inflammation & injury• Both humoral (Hypersensitivity reactions II & III) and cell-mediated immunity (IV) are involved in joint pathology
•Type III mechanisms are involved in extra-articular manifestationsDiagnostically important Antibodies • Rheumatoid factor, an autoantibody against denatured self-IgG is detected in the serum of 80% of R.A. In the appropriate clinical context, it is a useful screening test, although not specific to R.A. |
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Term
| Sjogren's (sicca) syndrome |
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Definition
| salivary and lacrimal gland destruction → dry mouth, dry eyes |
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Term
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Definition
| Both skin and skeletal muscle are affected |
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Term
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Definition
| skeletal muscle inflammation and destruction → muscle atrophy |
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Term
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Definition
| Wide-spread progressive fibrosis in skin and visceral organs |
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Term
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Definition
| involves skin and connective tissue, generally benign |
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Term
| Autoimmune (Hashimoto's) thyroiditis |
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Definition
•Affects adult females (10-20X more common than males). Swollen neck due to variable enlargement of the thyroid gland
•Patient may be euthyroid, hyperthyroid or hypothyroid at different stages of disease
•Thyroid gland is infiltrated by both B and T lymphocytes; and slowly becomes hypotrophic as glandular epithelium is destroyed and replaced by fibrous tissue
•Immunopathologic mechanisms -Type II cytotoxicity and possibly Type IV cell-mediated cytotoxicity involved
•Autoantibodies to thyroid antigens (mainly thyroid peroxidase) are present in ~ 95% of patients
•Hypothyroidism develops slowly
•Patients will eventually require thyroid hormone |
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Term
| Diabetes mellitus (type 1 |
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Definition
| Islets of Langerhans injury by autoantibodies and T cell cytotoxicity |
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Term
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Definition
| (adrenal cortical failure) due to anti-adrenal cortical cell abs |
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Term
| Multiple endocrine autoimmunity |
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Definition
| (hereditary disease in which autoantibodies develop against several endocrine glands) |
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Term
| Acquired Immunodeficiency Syndrome (AIDS) |
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Definition
| •Pathogens that subvert the immune system and cause immunodeficiency : 1. Genetic variation within pathogens prevents effective long-term immunity (e.g., Streptococcus pneumoniae) 2. Mutation and recombination permit escape from immunity (e.g., influenza virus)3. Programmed gene rearrangements to change surface antigens (e.g., Trypanosomes)4. Hiding from the immune response (herpes viruses, such as EBV)The human immunodeficiency virus (HIV), which causes AIDS, has mastered the trade of compromising the immune system |
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Term
Severe combined
immunodeficiency
(SCID) |
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Definition
Immunodeficiency diseases can
also be caused by inherited
genetic defects: Overview of
cellular defects and one example
of defective
biochemical effector
mechanisms |
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Term
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Definition
• Defects in complement
components or their
regulators can impair
antibody responses and lead
to accumulation of immune
complexes
• Hereditary angioedema |
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Term
| Four examples of diseases caused mainly by dysfunctional T-lymphocytes |
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Definition
X-linked SCID [due to lack of common cytokine receptor chain]
Wiskott-Aldrich syndrome [WAS, X-linked]
Bare lymphocyte syndrome [lack of MHC class II on antigen-presenting cells
ADA (adenosine deaminase) or PNP purine nucleotide phosphorylase deficiencies |
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Term
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Definition
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Term
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Definition
[weak efficiency allele
of RAG] |
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Term
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Definition
[defective DNA double
strand break repair ] |
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