Diseases of the Immune System Flashcards
1
Q
What are the characteristics of an inflammatory response?
A
- nonspecific/generalized process ot neutralize & eliminate foreign entity
- acute/local inflammation
- neutrophils, macrophages, T-lymphocytes
2
Q
What are the characteristics of an immune response?
A
- response to neutralize & eliminate specific foreign entity
- identify & isolate antigens unique to a single pathogen
- T-lymphocytes, B-lymphocytes, NK cells, APC
3
Q
What are the cells of the immune system?
A
- intravascular leukocytes: monocyte, eosinophil, basophil, neutrophil, lymphocyte
- extravascular: histiocyte, plasma cell, mast cell
4
Q
What are the myeloid cells?
A
- nuetrophils: acute response
- eosinophils: respond to parasitic infection
- cytoplasmic granules
- basophils: histamine, heparin, serotonin -> anaphylactic shock
- monocytes: APC, chronic inflammation-> phagocytosis
5
Q
What are the lymphoid cells?
A
- T, B, NK
- CD4+/CD8+ influences function
6
Q
What is innate immunity?
A
- major role by epithelial barriers, neutrophils, macrophages, NK cells
- acute inflammation
- stimulates adaptive immunity
7
Q
What are natural killer cells in innate immunity?
A
- CD8- or CD4-
- important for immunoserveillance
8
Q
What is the humoral response in adaptive immunity?
A
- requires antigen-specific molecules
- more effective than innate immunity
- B lymphocyte
9
Q
What are T lymphocytes?
A
- thymus derived
- 70% of lymphocytes in blood
- recognize MHC-bound peptides on APC via TCR
10
Q
What are the classes of T lymophocytes?
A
- MHC class 2 -> CD4+ T cells
- MHC class 1 -> CD8+ T cells
11
Q
What is the role of CD4+ and CD8+ T cells?
A
- CD4+: interact with B cells, macrophages,produce cytokines, eliminate extracellular pathogens
- CD8+: cytotoxic T cells, destroy intracellular pathogens
12
Q
What are B lymphoytes?
A
- 20% of lymphocytes
- undergo antigen stimulation in lymph nodes/organs
- interact with CD4+ T cells
13
Q
What are the characteristics of the Ig families?
A
- 95% of circulating antibodies (IgG, IgM, IgA)
- IgG: coats microbes, targets for phagocytosis, promotes passive immunity
- IgG & IgM: activate complement system
- IgA: mucosal secretions
- IgE: tissue mast cells
- IgD: surface on B cells; not secreted
14
Q
What are aberrant inflammatory responses?
A
type 1, 2, 3, and 4 hypersensitivity
15
Q
What are the immune disorders?
A
- autoimmune disease
- transplant rejection
- immunodeficiency
16
Q
What is type 1 hypersensitivity (IgE)?
A
- allergy reaction; treated with anti-histamine
- immediate hypersensitivity
- Ab response to external antigen
- IgE binds & activates mast cells (histamine) -> affinity for Fc of IgE heavy chain
17
Q
When linked, what does IgE promote the release of?
A
- histamine, prostaglandins,cytokines
- results in vasodilation, mucus secretion, SM spasm, leukocyte activation
18
Q
What are the 3 subtypes of type 2 hypersensitivity?
A
- opsinization & phagocytosis
- inflammation & complement mediated
- antibody mediated
19
Q
What is opsonization & phagocytosis in type 2 hypersensitivity?
A
- C3b-dependent
- host cell opsonized with autoantibodies
- typified by thrombocytopenia purpura
- no association with inflammation
20
Q
What is iodiopathic thrombocytopenia purpura in type 2 hypersensitivity?
A
- low number of platelets in blood
- < 5000 platelets per cubic mL
- treated with platelet transfusion
- bone biopsy shows megakaryocytic hyperplasia
- pupura: 3-10mm hemorrhages
- petachae: < 3mmhemorrhages
21
Q
What is inflammation & complement mediation in type 2 hypersensitivity?
A
- autoantibodies on host cells activate C3a/C5a
- typified by Rh factor incompatibility, Goodpasture syndrome
22
Q
What is Goodpasture syndrome?
A
autoantibodies to domain of alpha 3 chain of collagen 4 (basement membrane)
23
Q
What is antibody mediated cellular dysfunction in type 2 hypersensitivity?
A
- autoantibodies impair host cell receptors without phagocytosis or inflammation
- typified by Graves disease or myasthenia gravis
24
Q
What is myasthenia gravis in type 2 hypersensitivity?
A
- caused by defect in transmission of nerve impulses to muscles (usually in the face)
- treated with pyridostigmine -> increase half-life of Ach
- presents as ptosis (drooping eyelids), diplopia (double vision), dyasarthria (difficulty speaking)
25
What is Graves disease in type 2 hypersensitivity?
* antibodies bind receptors on thyroid follicular cells
* scalloping of colloid (thyroid gland)
* hyperfunctional thyroid, exopathalmos
* treated with immunosuppressants & radioactive iodine
26
What is type 3 hypersensitivity?
* host antigen-autoantibody immune complex
* circulation of immuno-complexes in blood vessels
* depends on deposition of performed immuno-complexes
* typified by systemic lupus & scleroderma
27
What is systemic lupus in type 3 hypersensitivity?
* women > men
* form antigen-antibody complexes
* antinuclear antibodies: dsDNA
* glomerulonephritis leads to renal failure & death
* deposition of complexes causes malar (rash on skin)
* cryoglobulins produce Raynaud's phenomenon
28
What is systemic sclerosis in type 3 hypersensitivity?
* common among older women
* skin derived; progressive fibrosis
* can lead to dysphagia
* anitgen complexes
29
What are the 2 subtypes of systemic sclerosis?
* diffuse pattern: widespread skin, rapid progression, visceral involvement; Abs to DNA topoisomerase 1
* limited pattern: lmited ksin & visceral involvement, slow progression; Abs to centromere
30
What is CREST syndrome in systemic sclerosis?
associated with
* calcinosis
* Raynauds syndrome
* esophageal dysmotility
* scelrodactyly
* telangiectasia
31
What is type 4 hypersensitivity?
* delayed-type
* T-cell mediated to external or self Ag
* NO Abs
* 12-48 hours after exposure
* CD4+ T cells promotes cytokine secretion & tissue destruction
* CD8+ T cells directly cytotoxic to Ag
* TB and poison ivy reactions
32
What are the characteristics of a poison ivy recation in type 4 hypersensitivity?
* triggered by urushiol (external Ag)
* treated with methotrexate
33
What are the characteristics of a transplant rejection?
* incompatibility b/w donor & host
* autograft (donor=self)
* allograft (donor=identical twin)
* xenograft (donor=another species)
* split ( dead organ divided b/w 2 patients)
* domino ( mulitple transplants)
34
What is a hyperacute transplant rejection?
* occurs within minutes to hours
* interaction of preformed host Abs
* vascular disorders
* acute fibrinoid necrosis in blood vessel walls precipitates occlusion
35
What is an acute transplant rejection?
* occurs within days-months in immunosuppressed patient
* cellular/humoral based
* require immunosuppressive therapy
* acute cellular response: CD4+ and CD8+ T cells
36
What 3 types of hypersensitivity are autoimmune?
types 2, 3, & 4
36
What is a chronic transplant rejection?
* over years
* intimal hyperplasia develops in graft blood vessels
* not retarded by immunosuppression
37
What is a graft vs host transplant rejection?
* occurs when donor lymphocytes respond to host MHC
* common in bone marrow trans.
* time onset varies
* acute: days to week after trans.; destruction of liver
* chronic: follows acute GvH or independ.
38
What is congenital immunodeficiency?
* severe immunodeficiency
* 6 months-2 years as repeated infections
39
What 3 types of hypersensitivity are autoimmune?
types 2, 3, & 4
39
What is Brutons disease in the B cell lineage of congenital immunodeficiency?
* X-linked recessive agammaglob.
* absence of immature (IgD/IgM) B cells
* depressed serum levels of all classes of IgGs
* normal T cell repsonses
* males > females
40
What 3 types of hypersensitivity are autoimmune?
types 2, 3, & 4
41
What is the B cell lineage of congenital immunodeficiency?
* X-linked recessive agammaglob. (Bruton's Disease)
* absence of immature
42
What is common variable immunodeficiency (CVID) in the B cell lineage of congenital immunodeficiency?
* prone to autoimmune disorders
* normal T cell responses
* immature B-cells present
* males=females
43
What is hyper IgM syndrome in the B cell lineage of congenital immunodeficiency?
* normal immature B cells
* normal/overproduction of IgM; fail to Ig isotype-switch
* X-linked recessive
* increased infections
44
What 3 types of hypersensitivity are autoimmune?
types 2, 3, & 4
45
What is IgA deficiency in the B cell lineage of congenital immunodeficiency?
* normal immature B cells
* normal production of IgM; normal isotype switch to IgG & IgE NOT IgA
* sinopulmonary infections and diarrhea
46
What is DiGeorge syndrome in the T cell lineage of congenital immunodeficiency?
* deficient T cell maturation
* T cell receptor capable of Ag recognition
* reduced T cell cytokine production
* thymic hypoplasia
* repeated infections
47
What is MHC class 2 deficiency in the T cell lineage of congenital immunodeficiency?
* inability to develop CD4+ T cells
* B cell and serum Igs are indirectly affected
* reduced T cell cytokine production
48
What are the characteristics of HIV?
* acquired immunodeficiency
* targets CD4+ T cells; eventually depletes
* surface protein gp 120 binds to Cd4+
* changes in gp 41 promote gp 120 cellular entry
* 7-12 years
49
What is leukopenia in non-proliferative WBC disorders?
* reduced lymphocytes
* secondary to disease or therapy/drugs
50
What is lymphopenia in non-proliferative WBC disorders?
* reduced granulocytes
* neutropenia as reduced neutrophils
51
What is neutrophilic leukocytosis?
* reactive proliferative disorder
* result of bacterial infection or sterile inflammation
52
What is eosinophilic leukocytosis?
* reactive proliferative disorder
* result of allergic recations & parasitic infections
53
What is basophilic leukocytosis?
* reactive proliferative disorder
* associated with conditions like neoplastic disease
54
What is lymphocytosis?
* reactive proliferative disorder
* associated with infections
* increased lymphocytes
* caused by EBV -> B ell proliferation
55
What is lymphadenitis?
* reactive proliferative disorder
* associated with lymphadenopathy
* acute: enlarged B cell germinal centers
56
What are the types of chronic lymphadenitis?
* follicular: activated B cells migrate into follicular zone
* paracortical hyperplasia: activation of T cells thta proliferate and displace B cell germinal centers
* sinus histiocytosis: distention of lymphatic sinusoids due to endothelial hypertrophy
57
What are the 3 sets of words of neoplastic WBC disease?
1. acute (fast/blastic) or chronic (slow)
2. myeloid (RBC/granulocyte) or lymphoid (T/B cells)
3. leukemia (bone marrow/thymus) or lymphoma (lymphoid tissues)
58
What is contained in the bone marrow?
* all hematopoietic stem cells
* progenitor lymphoid cells
* myeloid progenitor & differentiated cells
59
What is contained in the thymus & lymph nodes?
* thymus -> differentiated T cells
* lymph nodes -> differentiated B cells, some T cells
60
Any myleoid cancer has to be ....
a leukemia
61
What are the 4 types of leukemia?
1. ALL: acute lymphoblastic leukemia
2. AML: acute myeloblastic leukemia
3. CLL: chronic lymphocytic leukemia
4. CML: chronic myeloid leukemia
62
What is acute lymphoblastic leukemia (ALL)?
* 80% of child leukemias
* pre B/T cell origin
* bone marrow involvement
* cytopenia of normal mature hematopoietic cells
* 80% cure rate in all
63
What is acute myeloblastic leukemia (AML)?
* proliferation of precursor myeloid cells
* affects more adults (>50 years old)
* contains auer rods
* bone marrow involvement
* 50-80% remission with treatment
64
What is chronic myeloid leukemia (CML)?
* mature but abnormal myeloid
* associated with philadelphia chromosome
* bcr-abl fusion protein
* affects 25-60 year old
* slow disease progression
65
What is chronic lymphocytic leukemia (CLL)?
* B cell lineage
* asymptomatic
66
What is Hodgkin's lymphoma?
* has Reed-Sternberg cells
* bilobed (mirror image)
* large cells meausre 15-45 um
* express CD30 & CD15
* B cell derived
* contiguous spread
* cured with chemo
