Tumor Immunology Hypersensitivity Flashcards
What is a tumor
An abnormal growth resulting from uncontrolled proliferation with no physiologic funtion
other name for a tumor
Neoplasm (new growth)
What is Cancer
Malginant tumor
Difference between Benign and Malignant Tumors
Slow growth: Rapid Growth
Well-defined capsul: Not encapsulated
Not invasive: invasive
Well differentiated: pooly differentiated (anaplasia)
Low Mitotic index: High Mitotic index
Does not metastasize: Can spread distantly (metastasis)
what is cancer a predominantly a disease of
Aging
How does Cancer proliferate
Clonal
why does cancer spread so rapidly
as a mutation it is benifical to the cell to grow fast, so it has a selective advantage ocer its neighbored (increased groth or decreased apoptosis)
What needs to occur to have Full blown cancer
4-7 mutations in a step wise accumulation of alterations occuring in specific genes
What are Carcinogens
Agents that can cause genetic mutation or alterations of gene expression that can lead to the development of cancer
Examples of Carcinogens
Chemical (Alcohol, asbestos, benezene, tobacco, aluminum)
Radioactive (plutonium-239, radon-222, iodine-131)
Pathogens (Epstein-Barr Virus, H. pylori, Hep B and C, HPV)
What do Cancer-Causing Mutations affect
Activation of growth-promotion pathways
Block antigrowth signals
Prevent apoptosis
Turn on telomerase and new blood vessel growth
Allow tissue invasion and distant metastasis
What are tumor associated antigens
Normal proteins that are expressed in abnormally high levels, in an abnromal location, or during an abnormal stage of cellular development
What are tumor specific Antigens
Macromolecuels (PR or carbs) that are unique to the tumor
What suppresses many developing malignancies
An efficient immune system
Defects in the immune system increase the risk of what type of cnacer
Viral assocaited
What is antitumor immunity
Innate and adaptive responses that can contribute to tumor destrucution and elimiation
Can Tumors evade the immune system
Yes
What is Protumor immunity
Evidence that some immune responses can perpetuate tumor development (Chronic inflammation)
Innate cells invovled in Antitumor Immunity
MAcrophages (M1)
Neutrophils (N1)
Dendritic Cells
NK cells
What can innate antitumor cells recognize
DAMPS that may be upregulated during tumor growth
How do DAMPS forom tumors contribute to inflammation
Via IFN gamma, IL-12, TNF-alpha, ROIs, and RNIs
How are NK cells activated to a tumor
IFN gamma
What are Nateral Killer Cells biolgoically
Lymphoid cells that contain perforin and grnzymes
what do NK cells recognize
MHC I but are not ag specific
What is the ROll of NK cells in fighting off tumors
Important for removing virally-infected and tumor
cells
How to NK cells kill
Antibody binds antigen on the surface of target cells
Fc Receptors on NK cell recognizes bound antibody
Cross linking of Fc Receptors signals the NK cells to kill the target
Target cell dies by apoptosis
What drives the Th1 response to tumors
IFNgamma and IL-12
what lymphocytes are invovle in adaptive antitumor immunity
Cytotoxic T lymphocytes (CTLs)
What must be broken for a T cell to be invovled in ANtitumor immunity
A break in central tolerance in order for a T cell to be involved
Cells in Protumor Immunity
MAcrophages (M2) Dendritic CElls Regulatory T cells Th2 cells Myeloid-derived suppressors cells
Roll of Macrophages (M2) in protmor Immunity
PRomote Angiogenesis and invasiveness
Roll or Dendritic cells in Protumor Immunity
Suppress T cell functions
Problem with inflammation relation with cancer
an important factor in the development of cancer
what does Active inflammation do for cancer
Predisposes a person to cancer by stimulating a wound-healing reponse that includes proliferation and new blood vessel growth
Susceptible organs to get cancer from inflammation
GI tract, Pancrease
Thyroid gland
PRostate, urinary bladder
Pleura, skin
Anti-tumorigenic effect of Dendritic cell
Release Cytotoxic Cytokines
Antigen presentation to T cells
PRo-tumorigenic roll of Dendtriic Cells
Suppress T cell function
Promote tumor growth and progression
Anti-Tumorigeneic role of T cells
Directly lyse cancer cells
Release cytotoxic cytokines
Pro-tumorigenic roll of T cells
Release tumor promoting cytokines
Anti-tumorigenic Roll of Treg
Restor homeostasis to reduce chronic inflammaion
Pro-tumorigenic roll of Treg
Suppresses anticancer immune responses
Stimulate inflammatory cytokine producion
Anti-tumorigenic roll of macrophages
RElease cytotociv cytokines
Antigen presentation to T cells
PRo-tumorigenic roll of MAcrophages
PRomote Angiogeneisis, tumor proliferation, chemotaxis, invasiveness, and metastis
Anti-tumorigenic roll of Myeloid derviced suppressor cells (MDSC)
Limited
Pro-tumorigenic Roll of MDSC
Suppress T cell function
REcruit immunosuppressive immune cells
Anti-tumorigenic roll of NK cells
Relase Cytotociv cytokines
Directly Cytotocix to Cancer cells
Pro-tumorigenic roll of NK cells
Limited
Conventional Cancer treatmetns
Surgery
Chemo
Radiation
When is surgery not good for cancer treatment
NOt good for diffuse cancers
Problem with Chemo to treat cancer
Non-specific
How does Chemo fight cancer
TArgets rapidly growing cels, but can also damages normal cels too such as immune cells, GI and Hair
Benifit of Ratiation over Chemo
More target than Chemo
How does Radiation Work to fight cancer
Radioactive substances generate ROIs that can severely damage tumor DNA causign the cells to die
Why is Monoclonal Ab good to fight cancer
Advantageous due to specificity, but first need to find a specific target
what must be found to use Monoclonal Ab
Tumor specific or tumor-associated antigens
What is HErceptin (trastubzumab) used to treat
Breast cancer treatment for patients with tuomrs that overexpres HER2
What is HErceptin (trastuzumab)
A monoclonal Ab that binds to HER
How does Herceptin work
PRomotes NK cell mediated ADCC
INterferes with HER2-directed Signa that promote tumor growth
How to do adoptive T cell transfer therapy
Remove T cells from patient
–Isolate T cells taht recognize cancer or T cell can be genetrically engineered to recognize cancer cells
Clonally expand cancer-specific T cells
Infuse PAtient with Cancer specific T cells
Types of Adoptive T cell transfer therapies
TIL (Tumor Infiltrating Lymphocytes)
TCR (T cell receptor)
CAR (Chimeric Antigen Receptor)
What type of Adoptive T cell transfer is the most advances
CAR T cell therapy
What is the main side effect of CAR T-cell therapy
Cytokine relase syndrome in which a patient feels flu symptoms for 5-7 days
What is CAR T-cell therapy approved for
PEdiatric Acute lymphoblastic Leukemia (ALL) and for adult with advanced lymphoma
3 main causes of hypersensitivies
Reaction to Sself (autoimmunity)
Reaction against Micrboes
Reaction against Envirnomental Antigens
Other name for Type persensitivityI HY
Allergy, Atopy, immediate hypersensitivity
when does Type I hypersensitivity occur
within minute after reexposure to antigen/allergen
What is The Type I Hypersensitivity response
Rapid IgE and Mast cell mediated vascular and smooth muscle reaction that is often followed by inflammation
What determines what reactions may affect due to type I hypersensitivity
depending on the route of allergen entry
Commonness of Tyep I hypersensitivity
Most common disorder of the immune system of about 20% of the population
Typr I hypersesnsitivity General sequence of envents
- Initial exposure to antigen and production of IgE antibodies
- Binding of IgE ab to Fc receptors on mast cells
- Cross-linking of bound IgE upon reexposure to allergen
- Release of mast cell mediators
What is Sensitization
Intial exposute to antigen and production of IgE antibodies in Type I Hypersensitivty
What occuring in Sensitization
Antigen presention to Th2 cell or Tfh cell Antigen bound B cell and Il-4 and CD40L causes class switching to IgE
Release of Mediators from mast cells in Type I Hypersensitivity leads to what
A biphasic Response
What are the Immediate Effects of Type I hypersensitivity
Dilation of Bloodvessel, increased vascular permeability, and smooth muscle contraction (the immediate reaction)
what is the Late response of Type I hyper sensitivity
Inflammation (late phase reaction)
What must bind to create Type I hypersensitivity
ANtigen-specific IgE
The Immeidate REsponse of MAst Cell Degranulation
Vasoactive amines (Histamines and sesroton) and Proteases Synthesis and secretion of lipid mediators (prostaglandins and leukotrienes)
what happens in the Late Phase reaction for MASt cell Degranulation
Synthesis and secretion of Cytokines (TNFalpha, IL-4, Il-5, GM-CSF) and Chemokines (MIP-1alpha)
Infiltration of eosinophils, monocytes, and nuetrophils
What do Eosinophils that come in response to mast cell degranulation do
Release granules containing reactive oxygen species, prostaglandins and Leukotrienes
Roll of Histamine and lipid mediates in Type I hypersensitivty
Vascular/smooth muscle response (immediate reactions)
Roll of Cytokines in Type I hypersensitivty
Inflammation (late phase reaction)
How common is Asthma
22 million americas, 6 millions
how often does Asthma ,kill
80% of deaths occur in low to low mid income countries
What does Asthma tend to do to someone
PRoduce extra mucus and breathing becomes hard
What are the most common signs of ASthma
Coughing
Wheezing
Shortness of breath
Triggers for Asthma
Airborne allergnes (pollen, animal dander, mold, corckroaches and dust mites)
Respiratory infections, such as common cold
Physical activity (exercise induced asthma)
Col air
Air pollutants and irritants such as smoke
Why does Asthma make it hard to breath
Muscles of the broncial tunes tighten and thicken
Air passages become inflammed and mucus filled making the air difficult to move
How is Asthma treated
Inhaled corticosteroids
Inhalaed long acting beta2 agonist
Leukotriene inhibitors
Cromolyn
What is the most effective long-term control mediation for asthma
Inhaled Corticosteroids
what is a inhaled corticosteroids
Flovent
How do Inhaled long actiing beta2 agonist fight asthma
Act on beta-adrenergic receptors to cause bronchodilation
why use inhaled long-acting beta2 agonists
As a rescue medication
What is an inhlaed long-acting beta2 agonist
Albuterol
How do Leukotriene inhibitors work
Hlep block the chain reaction that increases inflammation in your airways
example of Leukotreien inhibitors
Singulair
what is Cromolyn
Inhaled medication to help prevent mast cell degranulation
what drives an anaphylaxis response
Driven by systemic release of vasoactive amines and lipid mediators from mast cells
What does Anaphylaxis cause
Life-threatening drop in BP accompanied by severe bronchoconstriction
how to treat anaphylaxis
Epinephrine (vasocontrictor and bronchodilators) and antihistamine
THe most severe form of immeidate hypersensitivty
Anaphylaxis
what leads to different immeidate hypersensitivty syndromes
Mediators produced in different amounts and in different tissues
What is Type II hypersensitivty
Antibody Dependent Cytotoxicty
what occures in Type II hypersensitivty
Antibodies produced by the immune response that bind to antigens on own cell srufaces
What Antibodies tend to be involved in Type II Hypersensitivty
IgG and IgM isotypes
Binding of IgG and IgM isotypes to their own Cell surface due to Type II Hypersensitivty results in what
Activate Complement result inmembrane attack complex formation, ultimately to destruction of cells, inflammation, or intereference with normal cellular functoin
Target antigen of Autoimmune Hemolytic anemia
Erythrocyte membrane proteins
Target antigen of Graves’ Disease
Thyroid-stimulating hormone (TSH) receptor
Target antigen of Myasthenia gravis
Acetylcholine (ACH) receptor
Autoimmune hemolytics anemia mechanism of disease
Opsonization and phagocytosis of erythrocytes, complement-mediated lysis
GRaves’ disease mech of disease
Antibody-mediated stimuation of TSH receptors
Myasthenia gravis mechanism of Disease
Antibody inhibits ACH binding to receptor leading to downregulation of receptors
Clinicopathologic manifestations of autoimmune hemolytic anema
Hemolysis, anemia
Clinicopatholgoic manifestations of Graves’ disease
Hyperthyroidism
Myasthenia gravis Clinicopathologic manifestations
Muscle weakness
Paralyiss
How does Hemolytic disease of the NEwborn work
1st baby has RBC’s with Rh antigen
mom has Rh-specific B cell that creates Anti-Gh IgM and Memory cells to fight it
2nd pregnancy not has IgG and antiRh ab crosses placenta and attacks fetal RBS’s leading to erythroblastosis fetalis
Roll of Rhogam in fighting Hemolytic disease in the newborn
Prevents B cell activation and memory cell formation
How to treat Autoimmaves Diseaseune hemolytic anemia
Corticosteroids or blood transfusion
How to treat Hemolytic disease of the newborn
Rhogam injections (anti-Rh ab)
How to treat Graves Disease
Radioactive Iodine, anti-thyroid drugs, or thyroid removal
How to treat Myasthenia Gravis
Cholinesterase inhibitors and corticosteroids
What is Type III hypersensitivty
Immune complex-Mediated
a grouping of antigens bound to their specific antibodies
Immune complex
where do Ag-Ab complex clump and deposit
In blood vessels or tissues attracting an acute inflammatory reaction
what type of Immune complexes tend to be cleared by phagocytes
LArger immune complexes
Where do small immune complexes tend to deposite
In blood vessels or tissues
What do Small immune complexes act on
Ligate Fc receptors on leukocytes, leading to activation and tissue damage
What kinds of Antigens can Cause Type III Hypersensitivity
Exogenous and endogenous antigens
when does Type III hypersensitivty occur
within hours (3-10h) after exposure to antigen
where do Type III hypersensitivity immune complexes tend to accumulate
at sites where antigen is localized
Sites of turbulence (vessel branches) or high pressure (kidney glomeruli and synovium)
Because Type III Hypersensitivity locolize at sites of Turbulence and high pressure how does the disease manifest
Vaculitis, arthritis, or nephritis
Diseases Caused by type III hypersensitivity
Systemic Lupus erythematosus
Post-streptococcal glomerulonephritis
Serum Sickness
Antigen involved with Systemic Lupus Erythematosus
DNA
Nucleoproteins
others
Antigens involved with Postr-streptococcal glomerulonephritis
Streptococcal cell wall antigens
Antigens invovled with SErum sickness
Various proteins
Clinical manifestation of Systemic lupus erythematosus
Nephritis, arthritis Vasculitis
Clincial manifestation of Post-streptococcal glomerulonephritis
Nephritis
Clinical manifestations of Serum sickness
Arthritis
Vasculitis
Nephritis
Mechanisms of Type III Hypersensitivity
Mast cell activation
Macrophages release TNF_apha and IL-1 that induce the inflammatory cascade
Complement activation (C3a, C4a, and C5a)
what does Complement activation of Type III Hypersensitivity do
Stimulate mast cels to release more histamine, serotonin, and chemotactic factors
Attracts monocytes, neutrophils, and other leukocytes
Cells bearing Fc receptors for IgG (or IgM) and IgE may be crucial for what type of hypersensitivty
Antibody complex mediated hypersensitivity
Causes of Serum SIckness
Antivenom (serum from horses immunized with snake venoms_
Anti-lymphocyte globulin
Antibiotics
Steptokinase (a bacterial enzyme)
What is Antivenom
A source of Neutralizing antibodies to treat people with poisonous snake bites
What is anti-lymphocyte globulin
Animmunosuppressive agent used for transplant recipients
what is streptokinase used as
A thrombolytic agent used to treat heart attack patients
How to treat serum sickness
Avoid drugs, antihistamines,corticosteroids
Treating Lupus
NSAIDS, Corticosteroids, immunosuppressive agents
What kind of Recation is Type IV hypersensitivity
Cell Mediated
How does Type IV Hypersensitivity occure
Mediated by antigen-specific T cells which induce macrophage infiltration iin a sensitized individual
What initiates Type IV Hypersensitivity
Haptens
Ag presented by APC’s activates Th cells
Th Cells secrete cytokines with activate macrophages
what are haptens
Small molecules that must become bound to a larger carrier molecule in order to Illicit and immune or inflammatory responce
How are Th Cells activated in Type IV Hypersensitivty
Ag presented by APC’s
What is Type IV hypersensitivity also called
Delayed-type hypersensitivity (DTH) since the action takes 2-3 days to develop
What antibodies mediated Type IV Hypersensitivity
Not antibodies (Mostly Th cells)
what cells are important effector cells in the DTH response
Macrophages, CD8 T cells, and NK cells
what do Activated CD8 cells do in Type IV hypersensitivity
Destroy target cells on contact
How does CD* cells destroy target cells on contact
2 phases:
Sensitization
Elicitation
when does Sensitiziation ocur
During the first exposure to Ag
How long does Sensitization take to develop
Take 10-14 days
what happens during Sensitization during Type IV hypersensitivity
Angitegn presenting cells take up AG and present to T cells
Formation of CD4+ memory T cells specific for the Ag
When does Elicitation for type IV Hypersensitivity occurs
during reexposure to Ag
when does Elicitation develop for type IV exposure
within 24-48 hour
what happens in elicitation for type IV hypersensitivty
LC Ag presentaion to memory T cells at site of Ag entry
T cells release IGNgamma and Pro-inflammatory cytokines
Cytokines recruit macrophage, CTL, NK, and other efector cells
Types of Type IV Hypersensitivity
Tuburculin type hypersensitivity Contact Dermatitis Chronic Asthma Gluten-sensitive Enteropathy GRaft regjection
How does one get Tuburculin type Hypersensitivity
Injected into the skin
what mediates Tuburculin type Hypersensitivity
Th1 cells
How does one get Contact Dermatitis
Absorbed by the skin
what mediates Contact Dermatitis
Th1 Cells and/or CTL’s
How does one get Chronic Asthma
Inhaled
what mediates Chronic Asthma
Th2 cells
how does one get Gluten-sensitive enteropathy
Injgest
What mediates Gluten-sensitive enteropathy
poorly understood but evidence suggest that Th1 and Th2 are involed
what mediates Graft rejections
T cells
HOw to test if previously exposed.infected with Mycobacterium tuberculosis
Tuberculin Test (Mantoux PPD test)
how is the Tuberculin test done
Small amounts of Tuberculin are injected intradermally
24-72 hours a local T cell mediated inflammatory reactions evolves in individuals previously with Mycobacterium tuberculosis
what mediates response in the Tuberculin Test
TH1 cells and infiltrating macrophages and other inflammatory mediators causing visible swelling and redness
what type of hypersensitivity is Poison ivy
Contact dermatitis (type IV)
what are the response parts of poison ivy
Sensitization period and elicitation of allergic response on subsequent interactions
Common allergens associated with contact dermatitis
Poison oak, poison sumac, plants Nickel and other metals MEdication (antibiotics especially topical, topical anesthetics plus more) Rubber and latex Cosmetics Fabric and clothing Detergents SOlvents Adhesives Fragrances and perfumes Other chem
Therapeutic strategies for Type IV hypersensitivity for TB test injections
Usually self limiting
trerapeutic strategy for contact hypersensitivity due to type IV
Limit exposure
Corticosteroids
Antihistamines
Therapeutic stratogy for CHronic Asthma due to type IV hypersensitivity
Corticosteroids, bronchodilators, Cromolyn
Therapeutic stratogy for Crohn’s disease
Corticosteroids
Immunosuppressants
Biologics
How to remember what type of sensitivity is What
I: Allergy II: antiBody III: immune complex IV: Delayed (DTH) ABCD