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Flashcards in Immunology Deck (75):
1

HLA A3

hemochromatosis

2

HLA B27

PAIR
- psoriatic arthritis, ank spon, IBD, reactive arthritis

3

HLA DQ2/DQ8

celiac disease

4

HLA DR2

MS, hay fever, SLE, goodpasture, syndrome

5

HLA DR3

DM 1, SLE, Graves Disease

6

HLA DR4

RA, DM 1

7

HLA DR5

pernicious anemia, Hashimoto thyroiditis

8

IL-1

secreted by macrophages. endogenous pyrogen, also called osteoclast activating factor. causes fever, acute inflammation. activates endothelium to express adhesion molecules, induces cytokine secretion to recruit leukocytes
- "Hot T-bone stEAK"
- stimulates hot (fever), T cells, bone marrow, IgE, IgA, aKute phase reactants production

9

IL-2

secreted by all T cells, stimulates growth of helper, cytotoxic and regulatory T cels
- can be used for tumor regression in RCC and metastatic melanoma

10

IL-3

secreted by all T cells
- support the growth and differentiation of BM stem cells. functions like GM-CSF

11

IL-4

secreted by TH2 cells
- induces differentiation into TH2 cells, promotes growth of B cells
- enhances class switching to IgG and IgE

12

IL-5

secreted by TH2 cells
- promotes differentiation of B cells, enhances class switching to IgA
- stimulates the growth and differentiation of eosinophils

13

IL-6

secreted by macrophages and TH2 cells
- an endogenous pyrogen
- fever and stimulates production of acute phase proteins

14

IL-8

secreted my macrophages
- major chemotactic factor for neutrophils

15

IL-10

secreted by TH2 cells and Treg
- modulates inflammatory response, inhibits actions of activated T cells and Th1
- enhances IL4 and 5 secretion from TH2

16

IL-12

secreted by macrophages and B cells
- induces differentiation of T cells into Th1 cells
- activates NK cells

17

TNF-alpha

secreted by macrophages
- mediates septic shock, activates endothelium, causes leukocyte recruitment and vascular leak
- mediates cachexia

18

IFN gamma

secreted by Th1 cells
- has antiviral and antitumor properties
- activates NK cells
- increases MHC expression and antigen presentation in all cells
- used therapeutically in CGD

19

INF alpha and beta

- interferes with viral replication by halting protein synthesis in virally infected cells
- essentially results in apoptosis
- alpha used therapeutically in Hep B/C, Kaposi sarcoma, hairy cell leukemia, condyloma acuminatum, RCC and malignant melanoma
- beta used therapeutically in MS

20

T cell surface receptors

- TCR, CD3, CD28 (binds to B7 in APC)
- Helper T cells have CD4 and CD40 ligand
- Cytotoxic T cells have CD8

21

B cell surface receptors

- CD19, CD20, CD21 (EBV entry), CD40
- MHC II, B7

22

macrophage cell surface receptors

- CD 14, CD 40
- MHC II, B7
- Fc and C3b receptors

23

NK cell surface receptors

- CD 16 (binds Fc of IgG)
- CD 56 (unique marker for NK)

24

Type I HS reaction

- anaphylactic and atopic - free antigen cross links with IgE (aggregation of IgE-Fc receptors triggers degranulation) on mast cells/basophils triggering immediate release of histamine and tryptase (sensitive for mast cell activation)
- delayed response due to leukotrienes
- test: skin test for IgE

25

Type II HS reaction

- cytotoxic "cy-2-toxic" - IgG and IgM bind fixed antigen on enemy cell, leading to cellular destruction
- 3 mech: opsonization (phagocytosis or complement), complement mediated lysis (transfusion reaction), Ab dependent cell mediated tox with NK or macrophage
- test: direct and indirect Coombs

26

Coombs test

- direct tests for antibodies that have adhered to antigen (test Rh + baby with Rh- mom)
- indirect tests for antibodies that can adhere to other RBCs (test Rh - mom for Abs)

27

Type III HS reaction

- immune complex - IgG complexes activate complement, which attracts neutrophils that release lysosomal enzymes
- ex: serum sickness, arthus reaction
- III - 3 things stuck together - antigen-antibody-complement

28

serum sickness

immune complex idsease in which Abs to the foreigh proteins are produced (takes 5 days)
- immune complexes form and are deposited in membranes, where they fix complement --> tisue damage
- assoc with monoclonal Ab drugs
- fever, urticaria, arthralgias, proteinuria, lymphadenopathy 5-10 days after antigen exposure
- small vessel vasculitis with fibrinoid necrosis and intense neutrophil infiltration
- hypocomplementemia

29

arthus reaction

- local subacute type III HS reaction
- interdermal injection of antigen induces antibodies, which form complexes in the skin
- edema, necrosis and activation of complement
- test: IF staining

30

Type IV HS reaction

- delated (T cell mediated)
- sensitized T cells encounter antigen and then release lymphokines (leads to macrophage activation, no Ab involved)
- 4 T's - T lymphocytes, Transplant rejections, TB skin tests, Touching (contact derm)

31

What type of reactions characterize each HS reaction?

ACID
- I - Anaphylactic and Atopic
- II - Cytotoxic
- III - Immune complexes
- IV - Delayed (cell mediated)

32

Type I HS disorders

- anaphylaxis
- allergic and atopic disorders (rhinitis, hay fever, eczema, hives, asthma)

33

Type II HS disorders

- AI hemolytic anemia
- pernicious anemia
- ITP
- erythroblastosis fetalis
- acute hemolytic transfusion reactions
- Rheumatic fever
- Goodpasture syndrome
- Myasthenia gravis
- Bullous Pemphigoid
- Pemphigus Vulgaris

34

Type III HS disorders

- SLE, polyarteritis nodosa, PSGN, serum sickness, arthus reaction (swelling and inflammation following tetanus vaccine)

35

Type IV HS disorder

- MS, GBS, Graft v. Host disease, PPD, contact derm

36

allergic blood transfusion reaction

- Type I HS reaction against plasma proteins in transfused blood
- urticaria, pruritis, wheezing, fever
- treat with antihistamines

37

anaphylactic blood transfusion reaction

- severe allergic reaction
- IgA deficient pts need blood without IgA or this will happen
- dyspnea, bronchospasm, hypotension, respiratory arrest, shock

38

febrile nonhemolytic transfusion reaction

- Type II HS reaction
- host Abs against donor HLA antigens and leukocytes
- fever, headaches, chills, flushing

39

acute hemolytic transfusion reaction

- Type II HS reaction
- intravascular hemolysis due to ABO incompatibility or extravascular hemolysis due to host Ab reaction against foreign antigen on donor RBCs
- complement mediated
- fever, hypotension, tachypnea, tachycardia, flank pain, hemoglobinemia and jaundice

40

Bruton agammaglobulinemia

- X linked recessive defect in BTK - a tyrosine kinase gene - no B cell maturation
- presents with recurrent bacterial, enteroviral and giardia infections after 6 months
- normal CD19+ B cell count, dec pro-B, dec Ig of all classes
- absent/scanty lymph nodes and tonsils with no germinal centers

41

selective IgA deficiency

- most common primary immunodeficiency
- can see airway and GI (mucosal) infections, autoimmune disease (assoc with celiac), atopy, anaphylaxis to IgA containing products
- IgA < 7 mg/dL with normal IgG and IgM levels

42

common variable immunodeficiency

- defect in B cell differentiation due to B cell or helper T cell defect (cant make immunoglobulins)
- can be acquired in 20s-30s, inc risk of autoimmune disease, bronchiectasis, lymphoma, sinopulmonary infections
- bacterial, enterovirus and giardia infections
- decreased plasma cells, decreased immunoglobulins

43

C1 esterase inhibitor deficiency

- causes hereditary angioedema
- NO ACE inhibitors

44

C3 deficiency

increases risk of severe, pyogenic sinus and resp tract infections, inc susceptibility to type III HS reactions

45

C5-C9 deficiencies

- increased susceptibility to Neisseria infections, no ability to make MAC

46

DAC (GP1 anchored enzyme) deficiency

- causes complement mediated lysis of RBCs and PNH

47

Thymic aplasia (DiGeorge)

- 22q11 deletion, failure of 3rd and 4th pharyngeal pouches (no thymus or parathyroids)
- presents with hypocalcemia, recurrent viral/fungal infections, conotruncal abnormalities (ToF, truncus arteriosus)
- dec T cells, dec PTH, dec Ca
- no thymic shadow

48

IL-12 receptor deficiency

- decreased Th1 response, AR
- disseminated mycobacterial and fungal infections, may present after administration of BCG vaccine
- decreased IFN gamma

49

AD Hyper-IgE syndrome (Job syndrome)

- deficiency of Th17 cells due to STAT3 mutation --> impaired recruitment of neutrophils to sites of infection
- FATED: coarse Facies, staph Abscesses, retained Primary teeth, inc IgE, Dermatologic problems

50

Chronic mucocutaneous candidiasis

- T cell dysfunction (many causes)
- non invasive candida infections of the skin and mucous membranes
- absent in vitro T cell proliferation or cutaneous reaction in response to candida antigens

51

SCID

- several types, most important is adenosine deaminase deficiency (AR)
- adenosine accumulation is toxic to T and B cells
- FTT, chronic diarrhea, thrush
- recurrent bacterial, fungal, viral and protozoal infections
- no thymic shadow, no germinal centers
- DO NOT GIVE LIVE VACCINES
- treat with BM transplant

52

Ataxia-telangiectasia

- defects in ATM gene -- DNA double strand breaks -- cell cycle arrest
- triad: Ataxia (cerebellar defects), spider Angiomas, IgA deficiency
- inc AFP, dec IgA, IgG, IgE, lymphopenia and cerebellar atrophy

53

Hyper IgM syndrome

- defective CD40L on Th cells --> X linked recessive class switching defect
- severe pyogenic infections early in life, opportunistic infections
- inc IgM with all other lines down

54

Wiskott-Aldrich Syndrome

- WATER
- Wiskott Aldrich: Thrombocytopenic purpura, Eczema, Recurrent infections
- inc risk of autoimmune disease and malignancy
- dec to normal IgM and IgG
- inc IgE and IgA

55

Leukocyte adhesion deficiency

- defect in LFA-1 integrin (CD18) protein on phagocytes, impaired migration and chemotaxis, AR
- recurrent bacterial skin and mucosal infections, no pus formation, impaired wound healing, delayed umbilical cord separation
- inc neutrophils, none at infection site

56

Chediak-Higashi syndrome

- defect in lysosomal trafficking regulator gene (LYST)
- microtubule disfunction in phagosome-lysosome fusion, AR
- recurrent pyogenic infections by staph and strep, peripheral neuropathy, progressive neurodegeneration, infiltrative lymphohistocytosis
- giant granules in neutrophils and platelets, pancytopenia and mild coag defects

57

Chronic Granulomatous Disease

- defect in NADPH oxidase, no respiratory burst and dec ROS
- X linked recessive
- inc susceptibility to cat + organisms
- abnormal dihydrorhodamine (flow cytometry) test
- nitroblue tetrazolium due reduction test is negative (neutrophils will not turn blue)

58

acute transplant rejection

- CTLs activated against donor MHCs + humoral Abs develop after transplant
- leads to vasculitis of the graft vessels with dense interstitial lymphocytic infiltrate
- prevent/reverse with immunosuppressants (calcineurin inhibitors)

59

chronic transplant rejection

humoral and cellular, recipient T cells react against donor antigens presented on donor MHC
- irreversible damage
- heart - atherosclerosis
- lungs - inflammation/fibrosis of small bronchioles (bronchiolitis obliterans)
- liver - vanishing bile ducts
- kidney - vascular fibrosis, glomerulopathy, loss of glomeruli, atrophy

60

graft v. host disease

graft T cells proliferate in the immunocompromised host and reject host cells with "foreign" proteins --> severe organ dysfunction
- rash, jaundice, diarrhea, HSmegaly
- usually in BM and liver transplants
- potentially beneficial for BM transplant

61

cyclosporine

- calcineurin inhibitor that blocks cyclophilin
- blocks T cell activation by preventing IL-2 trascription
- used for rejection ppx, psoriasis, RA
- tox: nephrotox, HTN, HLD, hyperglycemia, tremor, hirsuitism, gingival hyperplasia

62

tacrolimus

- calcineurin inhibitor, binds FK506 binding protein (FKBP)
- blocks T cell activation by preventing IL-2 transcription
- used for rejection ppx
- tox: similar to cyclosporine, inc risk of diabetes and neurotoxicity, no gingival hyperplasia or hirsuitism

63

sirolimus

aka rapamycin
- mTOR inhibitor, binds FKBP
- blocks T cell activation and B cell differentiation by preventing IL-2 signal transduction
- used in kidney transplant rejection prophylaxis
- tox: anemia, thrombocytopenia, leukopenia, insulin resistance, HLD, non-nephrotoxic
- kidney "sir"vives

64

basiliximab

- monoclonal Ab blocks IL-2R
- kidney transplant rejection ppx
- tox: edema, HTN, tremor

65

azathioprine

- antimetabolite precursor of 6-mercaptopurine
- inhibits lymphocyte proliferation by blocking nucleotide synthesis
- used in rejection ppx, RA, crohns, glomerulonephritis, and other AI conditions
- tox: leukopenia, anemia, thrombocytopenia
- degraded by xanthine oxidase, tox increases with allopurinol

66

glucocorticoids

- inhibits NFkB
- suppress both B and T cell function by dec transcription of many cytokines
- used in rejection ppx, many AI d/o, inflammation
- tox: hyperglycemia, osteoporosis, central obesity, muscle breakdown, psychosis, acne, HTN, cataracts, peptic ulcers

67

alemtuzumab

- targets CD52
- used in CLL
- "alymtuzumab" used in chronic Lymphocytic leukemia

68

bevacizumab

- VEGF Ab
- used in colorectal cancer, RCC

69

cetuximab

- EGFR Ab
- used in stage IV colorectal cancer, head and neck cancer

70

rituximab

- CD20 Ab
- used in B cell non-Hodgkin lymphoma, RA and ITP

71

trastuzumab

- HER2/neu Ab
- used in breast cancer and gastric cancer

72

infliximab, adalimumab

- TNF alpha antibody
- used in IBD, rheumatoid arthritis, ank spon, psoriasis

73

natalizumab

- alpha 4 integrin Ab
- used in MS and crohns
- alpha 4 is used in leukocyte adhesion
- risk of PML in pts with JC virus

74

abciximab

- glycoprotein IIb/IIIa Ab
- anti-platelet agent for prevention of ischemic complications in pts undergoing PCI

75

denosumab

RANKL Ab
- used for osteoporosis, inhibits osteoclast maturation