Immunology Diseases

Question 1

Autoimmune Polyendocrine Syndrome Type 1 (APECED)

Answer 1

no negative selection, autoimmune disease where endocrine organs are damaged

Question 2

Ankylosing Spondyllitis

Answer 2

associated with HLA allele B27

Question 3

Rheumatoid Arthritis

Answer 3

associated with HLA allele DR4

Question 4

Inslin-dependent Diabetes Mellitus

Answer 4

associated with HLA allele DR3/DR4

Question 5

Acute Rejection

Answer 5

begins after a few days – CD8 T cells react against alloantigens in the graft – can be prevented by immunosuppressive therapy

Question 6

Chronic Rejection

Answer 6

occurs months/years after, due to fibrosis of graft

Question 7

Hyperacute graft rejection

Answer 7

caused by circulating preformed antibodies against graft cells – Type II Hypersensitivity

Question 8

Autoimmune hemolytic anemia

Answer 8

autoantibodies formed against RBCs, which are destroyed by complement

Question 9

Autoimmine thrombocytopenia

Answer 9

autoantibodies against platelets – platelets opsonized by IgG antibodies, removed by macrophages

Question 10

Goodpastures Syndrome

Answer 10

IgG autoantibodies formed against glomerular and alveolar basement membranes

Question 11

Myasthenia Gravis

Answer 11

autoantibodies against acetylcholine receptor at neuromuscular junctions block the receptor, which inhibits nerve impulses – results in severe weakness – antibody acting as antagonist

Question 12

Graves Disease

Answer 12

autoantibodies against TSH receptor turns on receptor constitutively – continuous stimulation of thyroid gland, leading to excess T3/T4 and hyperthyroidism – antibody acting as agonist

Question 13

Post-Streptococcal Glomerulonephritis

Answer 13

anti-strep antibody combines with strep antigen, deposits in glomerular wall

Question 14

Serum Sickness

Answer 14

antibodies to foreign serum (horse/mouse), result in complexes depositing in various tissues

Question 15

Systemic Lupus Erythematosus

Answer 15

autoantibodies against nuclear components of body, particularly DNA – deposit in many tissues (skin, joints, kidneys)

Question 16

Drug Rections

Answer 16

antibodies form against drug, deposit into tissues

Question 17

Arthus Reaction

Answer 17

localized Type III hypersensitivity – i.e. inoculation sites, hypersensitivity pneumonitis (repeated exposure causes high circulating IgG levels, results in Arthus reaction in lung)

Question 18

Contact Dermatitis

Answer 18

antigens penetrate skin, processed by dendritic Langerhans cells, presented to T cells in the lymph nodes – edema of epidermis

Question 19

Mantoux Reaction

Answer 19

when TB/PPD is injected into skin of patient with previous immune response to tuberculosis – redness, raised skin at site of injection

Question 20

Agranulocytosis

Answer 20

almost complete absence of polymononuclear cells

Question 21

Chronic granulomatous disease

Answer 21

PMN can phagocytose, but intracellular killing mechanism is defective – defect is in NADPH oxidase, needed for cytochrome B which produces superoxide anion in phagocytes

- recurrent bacterial/fungal infections
- can result in granulomas – mass of activated macrophages

Question 22

Leukocyte Adhesion Deficiency (LFA-1)

Answer 22

defect in LFA-1/adhesion molecules – leukocytes can not adhere to endothelium, CD8 cells can not bind to their target cells, and neutrophil action is impaired – results in recurrent bacterial infection and impaired wound healing

Question 23

Chediak-Higashi Syndrome

Answer 23

phagocyte vesicle fusion results in giant vesicles, impairment of endosome-lysosome fusion – gene defect unknown, causes recurrent bacterial infections

Question 24

X-linked Agammaglobulinemia (Bruton’s)

Answer 24

defect in tyrosine kinase, which leads to failure of differentiation from pre-B cells – means no germinal centers, no mature B cells – pre-B cell count is normal – treated with IVIG – occurs in males

Question 25

IgA Deficiency

Answer 25

common disorder, many patients have no symptoms, others with respiratory/gastrointestinal infections – associated with IgG2/IgG4 deficiencies

Question 26

X-linked Hyper IgM Syndrome

Answer 26

defect in CD40 (B cell), CD40L (T cell), or AID result in inability to class switch – only IgM and IgD are produced – results in poorly developed germinal centers, recurrent infections – treat with IVIG
	- defect on T cell side also affects inflammatory response, since they can not interact with macrophages

Question 27

Transient Hypogammaglobulinemia of Infancy

Answer 27

delayed onset of Ig production, initially protected by maternal IgG

Question 28

Common variable immunodefiency

Answer 28

defect of terminal differentiation of B cells to plasma cells – treat with IVIG

Question 29

DiGeorge Syndrome

Answer 29

lack of thymus, no mature T cells (no differentiation) – deletion on chromosome 22
- CATCH 22 – Cardiac problems, Abnormal face, Thymic hypoplasia, Cleft palate, Hypocalcemia (absent parathyroid gland), chromosome 22

Question 30

T Cell Activation Defects

Answer 30

CD3 defect, signal transduction defects, cytokine defects, IL-2R defects, etc

Question 31

SCID

Answer 31

Severe combined immunodeficiency
no B cells, both humoral and CMI defective
many variants – treat with stem cell transplantation
- defective IL-2 receptor (70%)
- ADA deficiency
- Bare lymphocyte syndrome – no HLA molecules on cell
- ZAP70 defects (signal transduction goes bad)

Question 32

Ataxis Telangiectasia

Answer 32

funny gait” – “red spiders” on skin – defect in DNA repair

cannot be treated with stem cell trasplant

Question 33

AIDS

Answer 33

gp120 binds to CD4 molecule on T cell, and gp41 binds to chemokine receptor CCR5 – uses connections to fuse with plasma membrane of cell – rapid drop in CD4+ cells (from CD8 killing, apoptosis, destruction of lymph nodes)
- diagnosis – 1) presence of HIV antibody, 2) reversal of CD4:CD8 ratio, 3) HIV RNA serum levels

Question 34

psoriasis

Answer 34

t cells attacking kerotinocytes in the skins

Question 35

Crohns disease

Answer 35

T cells attacking something in bowel

Question 36

MS

Answer 36

t cells attacking myelin basic protein in brain