Autoimmune

Question 1

Autoimmune diseases

Answer 1

• breakdown of tolerance
• genetic factors are important
• original insult
• some autoimmune diseases are organ-specific (type II) and others systemic in distribution (type III)

Question 2

Breakdown of tolerance

Answer 2

“tolerance” is developed as part of becoming immunocompetent

Question 3

genetic factors important in autoimmune disease

Answer 3

affected members may not develop the same autoimmune disease; some people may have more than one autoimmune disease (tendencies are what’s inherited)

Question 4

Original insult in autoimmune

Answer 4

• may be identifiable - often drug, virus, or bacteria

- often preexisting infections that leave no trace

Question 5

Theories of autoimmune disease development

Answer 5

1. Normal self-antigens are altered by a drug, pathogen, or other mutation and are no longer seen as “self” (no longer look like your own)
2. antibodies against foreign antigens cross-react with a similar self-antigen
3. Clonal deletion theory

Question 6

Clonal deletion theory

Answer 6

suggests that self-reactive lymphoid cells are eliminated during immunological development

Question 7

SLE stands for?

Answer 7

Systemic Lupus Erythematousus

Question 8

Epidemiology for SLE

Answer 8

• 1 in 2,500 people
• 10x more women than men
• familial (ID twins have 30% concordance rate)
• 5 year survival rate = 93-95%
• mortality is low, but impose on quality of life is high

Question 9

Type III SLE

Answer 9

Has a wide range of symptoms including:

• arthritis (90%) - complexes stuck in synovial membranes
• vasculitis and rash (75%) - stuck in blood vessels of skin
• kidney disease (40-50%) - stuck in glomerulus
• blood abnormalities (50%)
• cardiovascular disease (30-50%) - unknown mechanism but there’s correlation

Question 10

SLE info

Answer 10

large variety of autoantibodies are produced including ones against DNA and RNA ( = ANA’s: anti-nuclear antibodies)

Question 11

Treatment of SLE

Answer 11

• glucocorticoids/ corticosteroids - strong anti-inflammatory
• antimalarials - no known reason
• monoclonal antibody (anti-body against autoantibodies)

Question 12

Downside of long-term corticosteroid treatment of SLE

Answer 12

• increased susceptibility to infections
• atherosclerosis -> stroke, Coronary Artery Disease (heart attack)
• obesity -> hypertension, diabetes type 2
• Cushing’s disease (hypercorticoidism: over tim. adrenal gland)
• others

Question 13

Immunodeficiency diseases

Answer 13

• primary (congenital)
• secondary (acquired): as a result of infections, metabolic diseases, cancer or treatment
• may involve primarily B cells or different types of T cells or it may be generalized

Question 14

All immunodeficiencies are characterized by ___________

Answer 14

lymphopenia (lymphocytes not making antibodies)

Question 15

Primary Immunodeficiency

Answer 15

• SCID (severe combined immunodeficiency)
• lack both T and B cells
• thymus is hypoplastic (never gets big) and lymph nodes are small
• used to die early in infancy
• new treatments are bone marrow transplant and gene therapy trial (14/16 worked)

Question 16

AIDS stands for?

Answer 16

Acquired immunodeficiency syndrome

Question 17

syndrome

Answer 17

a group of symptoms that occur together

Question 18

about AIDS

Answer 18

• HIV (human immunodeficiency virus)
• HIV as an affinity for T cells and monocytes
• macrophages can therefore also be infected, as well as fixed tissue phagocytes)
• HIV is cytotoxic - a depletion of these cells is typical of AIDS
• initial infection simulates B cells to produce antibodies, allowing most infected people to enter a latent stage
• latent = hidden (Aka asymptomatic)

Question 19

AIDS process

Answer 19

• eventually both cell-mediated T cell and humoral B cell immunity both become depressed
• individuals can not defend themselves from infection and may die from a minor disease that overwhelms their immune system (chicken pox most common killer in children)
• some patients also develop tumors of different kinds (lymphomas, Kaposi’s sarcoma)
• HIV virus may act as an oncogene

Question 20

Four groups of HIV-infected persons

Answer 20

1. Acute illness
2. Asymptomatic infection
3. Generalized lymphadenopathy
4. other diseases superimposed

Question 21

Acute illness

Answer 21

• occurs in 50%, 3-6 weeks post-exposure
• nonspecific symptoms which last 2 to 3 weeks, then spontaneously disappear
• during this period, some patients develop antibodies

Question 22

Asymptomatic infection

Answer 22

• variable duration (few months - few years)

- no symptoms, but carries the virus and is infectious

Question 23

Generalized Lymphadenopahty

Answer 23

• in patients who were initially asymptomatic, or develop early on and persist
• lymphadenopathy - abnormal, usually enlarged LN

Question 24

Other diseases superimposed

Answer 24

• opportunistic infections = organisms that only cause infections when the immune system is suppressed
• gastrointestinal disorders
• central nervous system involvement
• neoplasia (lack of immunosurveillance)