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193 Cards in this Set
- Front
- Back
Lymph node - functions
|
Non-specific filtration by Macs
Storage and activation B/T cells Antibody production |
|
Lymph node follicle
|
Site of B-cell localization and proliferation
Located in outer cortex Primary follicle: Dense and dormant Secondary follicle: pale central germinal centers and are active |
|
Lymph node medulla
|
Medullary cords: Plasma cells
Medullary sinuses: Macs and reticular cells |
|
Lymph node paracortex
|
Houses T-cells
Region of cortex between follicles and medulla Paracortical hyperplasia in extreme cellular immune response (i.e. viral--EBV) Not well developed in DiGeorge's syndrome |
|
Lymph node drainage
Upper limb, lateral breast |
Axillary
|
|
Lymph node drainage
Stomach |
Celiac
|
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Lymph node drainage
duodenum, jejunum |
Superior mesenteric
|
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Lymph node drainage
Sigmoid colon |
Colic --> Inferior Mesenteric
|
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Lymph node drainage
Rectum (lower part) Anal canal (above pectinate line) |
Internal Iliac
|
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Lymph node drainage
Anal canal below pectinate line |
Superficial inguinal
|
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Lymph node drainage
Testes |
Superficial and deep plexus --> para-aortic
|
|
Lymph node drainage
Scrotum |
Superficial inguinal
|
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Lymph node drainage
Superficial Thigh |
Superficial inguinal
|
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Lymph node drainage
Lateral side of dorsum of foot |
Popliteal
|
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Lymph node drainage
Right arm and right half of head |
Right lymphatic duct
|
|
Thoracic duct drainage
|
collects most of the lymph in the body
drains into the systemic (blood) circulation at the left brachiocephalic vein, between where the left subclavian vein and left internal jugular connect |
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Sinusoids of the spleen
|
Long, vascular channels in red pulp with fenestrated "barrel hoop" BM.
Macs found nearby. |
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T-cells in the spleen
|
Found in the PALS (periarterial lymphatic sheath) and red pulp
|
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B-cells in the spleen - location
|
Follicles within the white pulp
|
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Red pulp of the spleen - function
|
Mechanical filtration of RBCs
Reserve of monocytes |
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White pulp of the spleen - function
|
Active immune response through humoral and cellular pathways
Antibody production |
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What removes encapsulated bacteria in the spleen?
|
Macrophages
|
|
Mechanism of infxn susceptibility in splenic dysfunction/asplenia
|
Decreased IgM --> decreased C3b opsonization --> increased susceptibility to encapsulated organisms
|
|
Organisms of concern in splenectomized patients
|
S. pneumoniae
H. influenzae Salmonella N. Meningitidis |
|
Blood smear results post-splenectomy
|
Howell-Jolly bodies
Target cells Thrombocytosis |
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Sites of T and B-cell maturation
|
T: thymus
B: bone marrow |
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Thymus: Structural Organization and Function
|
Encapsulated. Cortex and medulla.
Site of T-cell differentiation and maturation. |
|
Where is the thymus embryologically derived from?
|
3rd branchial pouch.
|
|
Thymus: cortex and medulla
Cellular histology |
Cortex: dense with immature T-cells
Medulla: pale with mature T-cells and epithelial reticular cells, contains Hassall's corpuscles Corticomedullary junction: where + and - selection occur |
|
Thymocyte maturation process:
|
Occurs at corticomedullary junction
1. Immature thymocytes from BM make T-cell receptors by gene rearrangement 2. + selection (MHC restriction) for functional T-cells occurs in the cortex 3. - selection for autoreactive T-cells occurs in the medulla |
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Innate Immunity
|
Receptors that recognize pathogens are germline encoded.
Response to pathogens is fast and non-specific. PMNs, Macs, Dendritic cells, NK cells and complement |
|
Adaptive Immunity
|
Receptors that recognize pathogens undergo VDJ recombination during development.
Response is slow on 1st exposure, but memory response is faster and more robust. T-cells, B-cells, and circulating Ab |
|
Cytotoxic T-cell: function
|
CD8+
kills virus infected, neoplastic and donor graft cells |
|
Helper T-cell:
Types and functions |
CD4+
IL-12 --> Th1 Cell (cell-mediated response) IL-4 --> Th2 Cell (humoral response) |
|
Th1 cell function
|
CD4+ --> Cell mediated response
Make IL-2, IFN-g Activate Macs and CD8+ cells Inhibited by IL-10 |
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Th2 Cell function
|
CD4+ --> Humoral response
Make IL-4, IL-5, IL-10 Helps B-cells make Abs Inhibited by IFN-g |
|
MHC
|
Encoded by HLA genes
Present Ag fragments to T-cells and binds TCR |
|
MHC I
|
HLA-A, HLA-B, HLA-C
Expressed on almost all nucleated cells. Ag is loaded on RER of most intracellular peptides. Mediates viral immunity. Pairs with B2-microglobulin (aids in transport to cell surface) |
|
MHC II
|
HLA-DR, HLA-DP, HLA-DQ
Expressed only on APCs. Ag is loaded following release of invariant chain in an acidified endosome. |
|
HLA-A3
|
Hemochromatosis
|
|
HLA-B27
|
PAIR
Psoriatic arthritis Ankylosing spondylitis IBD Reiter syndrome |
|
HLA-B8
|
Grave's Disease
|
|
HLA-DR2
|
MS
Hay fever SLE Goodpasture's |
|
HLA-DR3
|
DM Type 1
|
|
HLA-DR4
|
RA
DM Type 1 |
|
HLA-DR5
|
Pernicious anemia (B12 deficiency)
Hashimoto's thyroiditis |
|
HLA-DR7
|
Steroid-responsive nephrotic syndrome
|
|
B-cell functions
|
Make Ab
IgG: opsonize bacteria, neutralize viruses Hypersensitivity rxns: Type I: IgE, allergy Type II: IgG/IgM, cytotoxic and Ab dependant Type III: IgG, immune complex deposition Preformed Abs can cause hyperacute organ rejection |
|
T-cell functions
|
CD4+: T-cells help B-cells make Ab and produce gamma interferon (activates Macs)
CD8+: Directly kills virus infected cells Type 4 Hypersensitivity: delayed cell-mediated Acute and chronic organ (allograft) rejection |
|
NK Cells
|
Only lymphocyte member of innate immunity
Uses perforin and granzymes to induce apoptosis of virally infected cells and tumor cells Activity is enhanced by IL-12, IFN-B, IFN-a |
|
What induces NK cells to kill?
|
When exposed to:
1) Non-specific activation signal on target cell 2) absence of MHC I on target cell surface |
|
T-cell glycoproteins
|
CD4: binds MHC II
CD8: binds MHC I CD3 complex: cluster associated with T-cell receptor Important in signal transduction |
|
3 Antigen Presenting Cells
|
Macs
B-cells Dendritic cells |
|
Macrophage-lymphocyte interactions
|
Activated lymphocytes and macrophages stimulate one another
Lymphocytes secrete IFN-g --> Macs Macs secrete IL-1, TNFa --> lymphocytes |
|
Effect of superantigens (S.pyogenes and S.aureus)
|
cross-link B-region of TCR to MHC II on APCs
results in uncoordinated release of IFN-g from Th1 cells and subsequent release of IL-1, IL-6 and TNF-a from Macs |
|
Effects of endotoxin/LPS from gram(-) bacteria
|
directly stimulate Macs by binding to endotoxin receptor CD14
|
|
Th cell activation
|
Signal 1: foreign antigen (phagocytosed by APC) is presented on MHC II and recognized by TCR on Th cell
Signal 2: "Costimulatory signal" is given by interaction of B27 (APC) and CD28 (Th) Th cell is now activated to produce cytokines |
|
Tc cell activation
|
Signal 1: Endogenously synthesized (viral or self) proteins presented on MHC I and recognized by TCR on Tc cell
Signal 2: IL-2 from Th cell activates Tc cell to kill virus infected cell |
|
B-cell class switching
|
Signal 1: IL-4, IL-5, IL-6 from Th2 cell
Signal 2: CD40 receptor activation by binding CD40L on Th cell |
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Antibody structure
|
Variable part of L and H chains recognize Ag
Fc portion of IgM and IgG fixes complement Heavy chain: Contributes to Fc and Fab fractions Light chain: Contributes only to Fab fraction Chains held together by disulfide bonds |
|
Fab
|
Ag binding fragment
Determines idiotype: only 1 antigenic specificity expressed per B-cell type |
|
Fc
|
Constant
Carboxy terminal Complement binding (IgG and IgM) Carbohydrate side chains Determines Isotype (IgM, IgD, etc) |
|
Functions of Abs
|
Opsonization: promotes phagocytosis
Neutralization: prevents bacterial adherence Complement activation: activates complement, enhancing opsonization and lysis |
|
Ab diversity is generated by:
|
1. random recombination of VJ (light-chain) or V(D)J (heavy) chain genes
2. Random combination of heavy chains with light chains 3. Somatic hypermutation (following stimulation) 4. Addition of nucleotides to DNA during recombination by terminal deoxynucleotide transferase |
|
B-cell isotype switching
|
Alternative splicing of mRNA, mediated by cytokines and CD40L
Mature B-cells express IgM and IgD on surfaces Can differentiate by isotype switching into plasma cells that secrete IgA, IgE or IgG |
|
IgG
|
Main Ab in secondary (delayed) response to Ag.
Most abundant. Fixes complement Crosses placenta (provides passive immunity in infants) Opsonizes bacteria Neutralizes bacterial toxins and viruses |
|
IgA
|
Prevents attachment of bacteria and viruses to mucous membranes.
Does not fix complement. Found in secretions (saliva, tears, mucus) and breast milk (colostrum) |
|
IgM
|
Produced in the primary (immediate) response to an antigen.
Fixes complement Does not cross the placenta |
|
Antigen receptors on the surface of B-cells
|
IgM and IgG
|
|
IgD
|
Unclear function.
Found on surface on many B cells and in serum. |
|
IgE
|
Binds mast cells and basophils.
Cross links when exposed to allergen, mediating Type I (immediate) hypersensitivity through release of histamine. Mediates immunity to worms by activating eosinophils. Lowest concentration in serum. |
|
Ig Allotype
|
Polymorphism - Ig epitope that differers among members of the same species.
Can be on light or heavy chain. ALLotypes represent different ALLeles. |
|
Ig Isotype
|
Ig epitope common to a single Ig class.
Ig MADGE |
|
Ig Idiotype
|
Specific for a given antigen. Ig epitope determined by Ag-binding sites.
Hypervariable region is unique. |
|
Thymus-independent Ag
|
Antigens lacking a peptide component.
Cannot be presented by MHC to T-cells. Stimulate release of IgM Abs only and do not result in immunologic memory. Ex: LPS from cell envelope of gram (-) bacteria and polysaccharide |
|
Thymus-dependent Ag
|
Ag containing a peptide component.
Class switching and immunologic memory occur as a result of direct contact with Th cells (CD40-CD40L interaction). Release of IL-4, IL-5, IL-6. Ex: H.influenzae vaccine |
|
IL-1
|
Secreted by Macs --> acute inflammation.
Recruit leukocytes Activates endothelium to express adhesion molecules Endogenous pyrogen |
|
IL-2
|
Secreted by Th cells.
Stimulates growth of helper and cytotoxic T-cells. |
|
IL-3
|
Secreted by activated T-cells.
Growth and differentiation of bone marrow stem cells. (Similar to GM-CSF) |
|
IL-4
|
Secreted by Th2 cells.
Growth of B-cells. Enhances class switching to IgE and IgG. |
|
IL-5
|
Secreted by Th2 cells.
Differentiation of B-cells. Class switching to IgA. Production/activation of IgE. |
|
IL-6
|
Secreted by Th cells and Macs.
Production of acute phase reactants and Ig's. |
|
IL-8
|
Secreted by Macs.
Major chemotactic factor for PMNs. Help clear infxns. "Clean up on aisle 8" |
|
IL-10
|
Secreted by regulatory T-cells.
Inhibits actions of activated T-cells. Activates Th-2, inhibit Th-1. |
|
IL-12
|
Secreted by B-cells and Macs.
Activates NK cells and Th1 cells. |
|
Gamma interferon
|
Secreted by Th1 cells.
Stimulates Macs. Activates Th1, inhibits Th2. |
|
TNF
|
Secreted by Macs.
Septic shock. Leukocyte recruitment, vascular leak. |
|
Hot T-Bone stEAk
|
IL-1: hot (fever)
IL-2: stimulate T-cells IL-3: stimulate bone marrow IL-4: stimulate IgE production IL-5: stimulate IgA production |
|
Helper T-cells - cell surface proteins
|
CD4
CD3 CD40L CD28 TCR |
|
Cytotoxic T-cells - cell surface proteins
|
CD8
CD3 TCR |
|
B-cells
|
IgM
MHC II CD40 CD19 CD20 CD21 (receptor for EBV) B7 |
|
Macrophages - cell surface proteins
|
MHC II
CD40 B7 CD14 Receptors for Fc, C3b |
|
NK cells
|
Receptors for MHC I
Receptor for Fc of IgG CD56 |
|
All cells except mature RBCs
|
MHC I
|
|
Interferon mechanism
|
Proteins that place uninfected cells in anti-viral state.
Induce production of a ribonuclease that inhibits viral protein synthesis by degrading viral mRNA. "Interferes with viruses" |
|
Interferon functions
|
1. alpha and beta: inhibit viral protein synthesis.
2. gamma: increase MHC I and II expression and Ag presentation in all cells 3. activates NK cells to kill virus-infected cells |
|
Active immunity
|
Induced after exposure to a foreign antigen.
Slow onset. Long acting protection -- memory. |
|
Passive immunity
|
Receiving pre-formed Abs from another host.
Rapid onset. Short life-span of Abs (3 weeks). Ex: IgA in breast milk. |
|
Which toxins require the administration of preformed (passive) Abs?
|
Tetanus
Botulinum HBV Rabies "After exposure to Tetanus, Botulinum, HBV, Rabies, patients are given pre-formed Abs To Be Healed Rapidly" |
|
Complement system
|
System of proteins that interact to play a role in humoral immunity and inflammation.
|
|
MAC defends against what type of bacteria?
|
Gram negative
|
|
Classic pathway (complement)
|
Activated by complement proteins binding antigen-Ab complexes
IgM or IgG |
|
Alternative pathway (complement)
|
Activated by complement binding to molecules on microbial surfaces (non-specific activators, i.e. endotoxin)
|
|
Mannose-lectin pathway
|
Activated by mannose-binding lectin binding microbial surfaces
|
|
C3b
|
Main function is opsonization.
Aids in clearance of immune complexes. Increases internalization by phagocytic cells by opsonization. |
|
2 primary opsonins in bacterial defense
|
C3b and IgG
|
|
Which 2 molecules help prevent complement activation on self-cells?
|
DAF (decay-accelerating factor)
C1 esterase |
|
Complement proteins involved in viral neutralization
|
C1 - C4
|
|
Complement proteins involved in anaphylaxis
|
C3a and C5a
|
|
C5a
|
Anaphylaxis and PMN chemotaxis
|
|
Membrane Attack Complex is comprised of which complement proteins?
|
C5b - C9
Function: Lysis and Cytotoxicity |
|
Deficiency of C1 esterase
|
hereditary angioedema
C1 esterase inhibits C1, F12, kallikrein --> increased vasoactive substances |
|
Hereditary angioedema
|
C1 esterase deficiency
|
|
Deficiency of C3
|
Severe, recurrent pyogenic sinus and respiratory infxns
Increases susceptibility to type III hypersensitivity rxns |
|
Deficiency of C5-C8
|
Neisseria bacteremia
|
|
Susceptibility to Neisseria bacteremia
|
Deficiency of C5-C8
|
|
Deficiency of DAF
|
Complement-mediated lysis of RBCs and PNH
|
|
Complement mediated lysis of RBCs and PNH
|
Deficiency of DAF
|
|
Antigenic variation in Influenza virus
|
Major = shift --> "shit"
Minor = drift |
|
Some mechanisms for antigenic variation:
|
DNA rearrangement
RNA segment reassortment (influenza major shift) |
|
Examples of antigenic variation in bacteria:
|
Salmonella (2 flagellar variants)
Borellia (relapsing fever) Parasites (trypanasomes --> programmed rearrangement) |
|
Anergy
|
Self-reactive T-cells become non-reactive without co-stimulatory molecule.
B-cells also become anergic, but tolerance is less complete than in T-cells. |
|
Granulomatous diseases (8)
|
1. TB
2. Fungal infxns 3. Syphillis 4. Leprosy 5. Cat scratch fever 6. Sarcoidosis 7. Chron's 8. Berylliosis |
|
Granulomatous disease process
|
APC induces Th cell to release IFN-g
IFN-g induces monocyte --> Mac --> epithelioid cell --> giant cell |
|
granuloma
|
giant cell
epithelioid cell fibroblasts lymphocytes |
|
Type I Hypersensitivity
|
Anaphylactic and atopic - First and fast
Free Ag cross-links IgE on presensitized mast cells and basophils --> trigger release of vasoactive amines that act at post-capillary venules Rapid rxn after Ag exposure due to preformed Ab Test: Scratch test and radioimmunoabsorbent assay |
|
Type II Hypersensitivity
|
Antibody mediated.
IgM, IgG bind to fixed Ag on cell --> lysis (via complement) or phagocytosis Ab and complement lead to MAC Test: Direct and indirect Coomb's |
|
3 mechanisms of Type II hypersensitivity rxn
|
1. Opsonize cell or activate complement
2. Ab recruits PMNs and macs that incite tissue damage 3. Bind to normal cellular receptors and interfere with functioning |
|
Type III Hypersensitivity
|
Immune Complex
Ag-Ab (IgG) complexes activate complement --> attracts PMNs to release lysosomal enzymes. Immune complex = Ab-Ag-complement Ex: serum sickness and arthus rxn |
|
Which hypersensitivity types are Ab mediated?
|
Type I, II, III
|
|
Serum Sickness
|
Type III hypersensitivity
Abs to foreign proteins are produced (5 days). Immune complexes form and are deposited in membranes, where they fix complement --> tissue damage Now caused mostly by drugs --> fever urticaria, arthalgias, proteinuria, lymphadenopathy 5-10 days after Ag exposure. |
|
Arthus rxn
|
Type III hypersensitivity
local subacute Ab-mediated rxn Intradermal injection of Ag induces Ab --> form Ag-Ab complexes in skin Sx: edema, necrosis, and activation of complement Test: Immunofluorescent staining |
|
Type IV Hypersensitivity
|
Delayed (T-cell mediated) type
Sensitized T-cells encounter antigen and release lymphokines --> Mac activation (no Ab involved) Not transferable by serum. 4 T's : T-cells Transplant rejection TB skin test Touching (contact dermatitis) Test: patch test (i.e. PPD) |
|
4 Hypersensitivity Rxns:
|
ACID
Anaphylactic and Atopic (I) Cytotoxic (Ab-mediated) (II) Immune Complex (III) Delayed (cell-mediated) (IV) |
|
Type I Hypersensitivity: Disorders
|
Anaphylaxis (bee sting, food/drug allergies)
Allergies and atopic disorders (i.e. rhinitis, hay fever, eczema, hives, asthma) |
|
Type I Hypersensitivity: Presentation
|
Immediate, anaphylactic, atopic
|
|
Type II Hypersensitivity: Disorders
|
Hemolytic anemia
Pernicious anemia ITP Erythroblastosis fetalis Acute hemolytic transfusion rxns Rheumatic fever Goodpasture's syndrome Bullous pemphigoid Pemphigus vulgaris Grave's disease Myesthenia gravis |
|
Type III Hypersensitivity: Disorders
|
SLE
RA Polyarteritis nodosa Post-streptococcal glomerulonephritis Serum sickness Arthus rxn (i.e. after tetanus vaccine) Hypersensitivity pneumonitis (i.e. farmer's lung) |
|
Type IV Hypersensitivity: Disorders
|
DM Type I
MS Guillan-Barre syndrome Hashimoto's thyroditis GVHD PPD (test for TB) Contact dermatitis (poison, nickel) |
|
ANA, anti-dsDNA, anti-Smith
|
SLE
|
|
Anti-histone
|
drug induced lupus
|
|
Anti-IgG
|
aka rheumatoid factor
RA |
|
Anti-centromere
|
CREST/Sceleroderma
|
|
Anti-Scl-70 / anti-DNA topo I
|
Diffuse scleroderma
|
|
Anti-mitochondrial
|
Primary Biliary Sclerosis
|
|
Anti-gliadin, anti-endomysial
|
Celiac disease
|
|
Anti-basement membrane
|
Goodpasture's syndrome
|
|
Anti-desmoglein
|
Pemphigus vulgaris
|
|
Anti-microsomal, anti-thyroglobulin
|
Hashimoto's thyroiditis
|
|
Anti-Jo-1
|
Polymyositis
Dermatomyositis |
|
Anti-SS-A / anti-Ro
Anti-SS-B/ anti-La |
Sjogren's syndrome
|
|
Anti-U1 RNP
(ribonucleoprotein) |
Mixed connective tissue disease
|
|
Anti-smooth muscle
|
Autoimmune hepatitis
|
|
Anti-glutamate decarboxylase
|
Type I DM
|
|
c-ANCA
|
Wegener's granulomatosis
|
|
p-ANCA
|
other vasculitides
|
|
Bruton's aggamaglobulinemia
|
X-linked recessive
Defect in BTK (tyrosine kinase gene) Defect in B-cell differentiation/maturation Recurrent bacterial infxns after 6 mo (decreased maternal IgG) Opsonization defect Labs: Normal pro-B Decreased B-cells, Ab (all classes) |
|
Hyper-IgM syndrome
|
Defective CD40L on Thelper cells --> unable to class switch B-cells
Severe pyogenic infxns early in life Labs: Increased IgM Decreased all other Ig's |
|
Selective Ig deficiency
|
Defect in isotype switching --> specific class of Ig deficiency
Sinus and lung infxns Milk allergies and diarrhea Anaphylaxis (after exposure to blood products with IgA) Labs: IgA deficiency most common |
|
Thymic aplasia
|
22q11 deletion --> DiGeorge's
failure to develop 3rd and 4th pharyngeal pouches tetany (hypocalcemia) recurrent viral/fungal infxns (T-cell deficient) congenital heart and great vessel defects Labs: Absent thymic shadow in CXR Decreased T-cells, PTH, Ca |
|
Di George's Symptoms
|
CATCH
Cardiac anomalies (Tetralogy of Fallot) Abnormal facies Thymic aplasia Cleft palate Hypocalcemia |
|
IL-12 receptor deficiency
|
Decreased Th1 response
Disseminated mycobacterial infxns Labs: Decreased IFN-g |
|
Hyper-IgE syndrome
(Job's syndrome) |
Th cells fail to produce IFN-g
PMNs unable to respond to chemotactic stimuli FATED course Facies cold, non-inflamed staph Abscesses retained primary Teeth increased IgE Dermatologic problems (eczema) Labs: Increased IgE |
|
Chronic mucocutaneous candidiasis
|
T-cell dysfunction
Candida albicans infxns of skin and mucous membranes. |
|
SCID
|
Several types --> B and T-cell deficiency
Defective IL-2 receptor (most common, X-linked) Adenosine deaminase deficiency Failure to synthesize MHC II Ag Recurrent viral, bacterial, fungal and protozoal infxns Tx: Bone marrow transplant (no allograft rejection) |
|
Ataxia-telangiectasia
|
Defect in DNA repair enzymes
Triad: cerebellar defects (ataxia) spider angiomas (telangiectasia) IgA deficiency |
|
Wiskott-Aldrich syndrome
|
X-linked recessive defect.
Progressive deletion of B and T-cells. Triad - TIE: Thrombocytopenic purpura Infections Eczema Labs: Decreased IgM |
|
Leukocyte adhesion deficiency (type I)
|
Defect in LFA-1 integrin (CD18) protein on phagocytes
Recurrent bacterial infxns Absent pus formation Delayed separation of umbilicus Labs: Neutrophilia |
|
Chediak-Higashi syndrome
|
AR inheritance
Defect in microtubular function with decreased phagocytosis Recurrent pyogenic infxns Staph and strep Partial albinism Peripheral neuropathy |
|
Origin of Systolic murmur that Increases in intensity with Squatting to Standing (rapidly for 30 sec)
|
Hypertrophic cardiomyopathy
|
|
Syngeneic graft
|
From identical twin or clone.
|
|
Allograft
|
From non-identical individual of same species.
|
|
Xenograft
|
From different species
|
|
Hyperacute rejection
|
Ab mediated (type II)
Preformed anti-donor Abs in recipient Occurs in minutes after transplantation |
|
Acute rejection
|
Cel mediated - cytotoxic T-cells against foreign MHCs
Weeks after transplantation. Reversible with cyclosporin and OKT3 |
|
Chronic rejection
|
T-cell and Ab mediated vascular damage (obliterative vascular fibrosis)
Occurs months to years after transplantation. Irreversible. CTL perceives as Class I-MHCself presenting non-self antigen. |
|
GVHD
|
Grafted T-cells proliferate in irradiated ICH and rejects cells with foreign proteins
Severe organ dysfunction. Maculopapular rash, jaundice, hepatosplenomegaly, diarrhea |
|
Cyclosporine
|
Calcineurin inhibitor --> prevents IL-2 and receptor production. Block differentiation and activation of T-cells
Use: Transplant, AI disorders Toxicity: Viral Infxns Lymphoma Nephrotoxic (prevent with mannitol diuresis) |
|
Tacrolimus
|
Similar to cyclosporine. Binds FK-binding protein --> Inhibits IL-2 and other cytokine secretion.
Use: Potent, used in transplant Toxicity: Significant Nephrotoxicity Peripheral Neuropathy HTN Pleural effusion Hyperglycemia |
|
Azathioprine
|
Antimetabolite precursor of 6-MP.
Interferes with metabolism/synthesis of nucleic acids. Toxic to proliferating lymphocytes. Use: Kidney transplant, AI disorders (glomerulonephritis, hemolytic anemia) Toxicity: BM suppression Toxic effects of increased allopurinol |
|
OKT3 (muromonab-CD3)
|
Monoclonal Ab that binds CD3 on T-cell surface
Blocks T-cell signal transduction. Use: kidney transplant Toxicity: Cytokine release syndrome Hypersensitivity rxn |
|
Sirolimus / Rapamycin
|
Binds to mTOR.
Inhibits T-cell proliferation in response to IL-2 Use: Kidney transplant used in combo with cyclosporine and corticosteroids Toxicity: Hyperlipidemia, Thrombocytopenia, Leukopenia |
|
Mycophenolate mofetil (CellCept)
|
Inhibits de novo guanine synthesis and block lymphocyte production
|
|
Daclizumab
|
Monoclonal ab with high affinity for IL-2 receptor on activated T-cells
|
|
Aldesleukin (IL-2)
|
Recombinant cytokine
RCC, metastatic melanoma |
|
Erythropoietin (epoetin)
|
Anemias (esp. in renal failure)
|
|
Filgrastim (G-CSF)
|
Recovery of bone marrow
|
|
Sargramostim (GM-CSF)
|
Recovery of bone marrow
|
|
Alpha interferon
|
Hep B, C
Kaposi sarcoma Leukemias Malignant melanoma |
|
Beta interferon
|
MS
|
|
Gamma interferon
|
CGD
|
|
Oprelvekin (IL-11)
|
Thrombocytopenia
|
|
Thrombopoietin
|
Thrombocytopenia
|