Immunology Flashcards
List functions of the innate immune system.
Inflammation Recruitment of immune cells Activate complement Natural killer cytotoxicity Phagocytosis
List cells of the innate immune system.
Erythrocyte Eosinophil Monocytes - dendritic cells, macrophages Basophil Neutrophil Megakaryocyte
What innate cells are found in the tissue?
Mast cell
Macrophage
Dendritic cells
What is the difference between MHC 1 and MHC 2 presentation?
MHC1 = all nucleated cells and platelets have it, present to CD8
MHC 2 = antigen presenting cells, present to CD4+
Where do T cells encounter antigens?
Lymph nodes
How do dendritic cells present antigens?
Via MHCII
What cells are the key players of the adaptive immune response?
B (differentiate to plasma cells) and T lymphocytes
What cytokines are released from Th1 cells?
IFN gamma
What cytokines are released from Th2 cells?
IL-4, 5, 13
What cytokines are released from Th17 cells?
IL-7A, 17F, 22
What helper cells are particularly good at triggering activation of mast cells and eosinophils?
Th2
What helper cells are particularly good at triggering activation of macrophages?
Th1
What helper cells are particularly good at triggering activation of netrophils?
Th17
What is the function of cytokines?
Regulate and co-ordinate cells of innate and adaptive immune responses
How to cytotoxic T cells kills cells by inducing apoptosis?
IFN and TNFa
FasL
Perforin and granzymes
What kind of cell is a natural killer cell?
Innate
What is the function of NK cells?
Kill infected cells
Produce cytokines to stimulate macrophages, Th1 and CD8+ cytotoxic
What is the function of B lymphocytes?
Neutralization of microbe, phagocytosis, complement activation
Opsonisation
Antibody-dependent cellular toxicity
What antibody is a pentamer?
IgM
What antibody is a dimer?
IgA
What antibody is for parasitic infections and allergy?
IgE
Where is IgA contained?
In secretions?
What antibody is best at activating complement?
IgM
What antibody is responsible fro memory in a secondary antigen exposure?
IgG
List physical and chemical barriers of the immune system.
Intact mucosal membranes Lysozymes in tears Normal flora Fluhsing in urinary tract Mucociliary escalator Acidic pH of stomach Intact skin with sebum maintaining pH
What lymphatic tissues are found in membranes?
Mucosa-associated (MALT)
Bronchus associated
Gut associated
List cells formed in the myeloid lineage.
Megakaryocyte, mast cells, myeloblasts, erythrocytes
What are formed from megakaryocytes?
Platelets
What are formed from myeloblasts?
Basophil
Eosinophil
Neutrophil
Monocyte
What are the two types of B lymphocytes?
Plasma cells and memory B cells
What system removes erythrocytes?
Reticuloendothelial system
What are the main targets of mast cells?
Parasites and allergens
What cells contain histamine and target parasites?
Basophils
What are the first cells that migrate to the site of infection, targeting bacteria and fungi specifically?
Neutrophil
What immune cells target parasites to big for phagocytosis?
Eosinophils
What 2 types off cells do monocytes become?
Macrophages
Dendritic cells
A dendritic cell is a professional APC. How does it present antigens?
Present to CD4+ via MHC II, releasing cytokines
How do natural killer cells work?
Granules contain proteins such as perforin and proteases
Activated by IFN and macrophage derived cytokines
List three types of T lymphocytes.
CD4+
CD8+
CD4+CD25+ (regulatory)
List cells involved in the innate immune system.
Phagocytes
Dendritic cells
NK cells
Complement
List cells that work by phagocytosis.
Basophil
Neutrophil
Monocytes (macrophages and dendritic cells)
List the classic professional antigen presenting cells.
Dendritic cells Macrophages Dendritic cells Langerhans cells B cells
What cells are involved in the adaptive immune system?
B cells
T cells
APCs
All nucleated cells display set markers via what protein?
MHC I aka HLA
What does MHC I present?
Self antigens and intracellular foreign antigens
What is the function of MHC II?
Present exogenous or extracellular antigens from pathogenic invaders
What cells contain MHCII?
Dendritic, macrophages, B lymphocytes
What does MHCI and II complexes bind to?
MHC I = CD8+
MHC II = CD4+
Discuss the cause of autoimmunity.
CD8+ cells destroy MHCI presenting self antigen i.e destroys healthy cell
How does the body prevent CD8+ cells binding and destroying self antigenic?
Immunological tolerance:
- Central = in primary lymph nodes
- Peripheral = in secondary lymphoid organs
Where do T and B cells develop central tolerance?
T - in thymus
B - in bone marrow
What cells are responsible fro peripheral tolerance?
Regulatory T lymphocytes
List conditions which would block chemical/physical barriers of immunity.
Mucositis Sjogren's syndrome Cystic fibrosis Toxic megacolon due to C difficile Burns
What are the primary lymphoid organs?
Bone marrow and thymus
What are secondary lymphoid organs?
MALT, Spleen, Peters patches, tonsils, lymph nodes
Name an immune cell responsible for recognising a viral infected host cell.
NK cell
List cells capable of phagocytosis.
Macrophage
Basophil
Neutrophil
Monocyte
Can eosinophils phagocytose?
No
What cell types are responsible for targeting large parasites that are too large for phagocytosis?
Mast cells
Basophils
Eosinophils
How are T cells developed in thymus?
Alpha and beta chains on T cell receptor (TCR), contains complimentary determining regions (CDR)
What is V(D)J recombination?
Occurs in developing T cells - process of genetic changes which create a diverse selection of Ag binding sites
List the steps of T lymphocyte development.
Double -ve –> double +ve –> positive selection –> interaction with MHC –> negative selection –> reacts appropriately
What are the 3 mechanisms used by CD8+ T cells?
FasL
IFN and TNFa
Perforin and granzymes
What is the function of helper T cells?
Activates other immune cells by releasing T cytokines
B lymphocyte antibody class switching
Activation and growth of cytotoxic T cells
Maximise activity of phagocytes
What cytokines are released by Th1 cells?
IFN gamma
What cytokines are released by Th2 cells?
IL -4, 5 and 13
What cytokines are released by Th17 cells?
IL-17,21,22
What Th cells have roles in allergy?
Th2
What occurs with increased Th1?
Type 4 hypersensitivity e.g MS
What occurs with increased Th2?
Type 1 hypersensitivity e.g Asthma
What occurs with increased Th17?
Chronic pro-inflammatory state (RA)
What is the function of Treg?
Suppress activation. proliferation and cytokine production of CD4 and CD8 lymphocytes
Monitor self tolerance
What cytokines are released by Treg?
IL-10 and TGF-beta
What produces antibodies?
Plasma
What is the function of the Fc region on the antibody?
Communicate with other components of the immune system
What is the only isotope that can cross the placenta?
IgG
What antibody is involved in the primary response?
IgM
List functions of antibodies.
Bind to Ags - immune complexes
Act as opsonins for phagocytosis
Activate complement cascade
Antibody Dependent Cellular Cytotoxicity (ADCC)
During ADCC, what does the Fc region bind to?
CD16
If Fc region binds to CD16, what happens?
Perforin and granzymes released –> apoptosis
Activates macrophages, eosinophils and neutrophils –> release granules and toxic enzymes
What are the 3 mechanisms of B cell activation?
Th dependent
Th independent (B cells activated by antigens)
Memory B cells
What is class switching?
Change in Ab heavy chain - same antigen specificity but acts with different effector cells
What antibody is found in the highest concentration in secondary infection
IgG
What occurs from a change in Ab heavy chain?
Change in isotype
Describe the innate immune system.
Fast, non-specific initial response
List cells involved in the innate immune system.
NK cells
Mast cells
Myeloblast cells
List functions of the innate immune system.
Antigen recognition Inflammation Recruitment of immune cells NK cytotoxicity Phagocytosis Opsonisation Activation of complement cascade
Give 2 examples of pattern recognition receptors.
Toll-like
C-type lectin
What do pattern recognition receptor recognise?
Pathogen associated molecular patterns (PAMPs) e.g lipopolysaccharide on gram -ve bacteria
OR damage associated molecular patterns (DAMPs)
Discuss the pathophysiology of inflammation.
Macrophages recognise PAMPs and DAMPs –> release IL-1 and TNFa
–> increase vascular permeability and neighbouring vessels express CAMS
Chemokine released to recruit/attract immune cells to point of inflammation
What is leukocyte extravasation?
Leukocytes move through endothelium to site of infection/inflammation
What loosens junctions between endothelial cells until neutrophils can squeeze through the gap into inflamed tissue?
Histamine and bradykinin
What are the cardinal signs of inflammation?
Dolar - pain (from histamine and bradykinin)
Calor - heat
Rubor - redness
Tumour - swelling
by vasodilation and increased vascular permeability
List atypical APCs.
Mast cells
Basophils
Eosinophils
List professional APCs.
Dendritic cells
Macrophages
B lymphocytes
What nucleated cell does not contain MHCI?
Platelets
How do NK cells differ from cytotoxic T cells?
Rapid response, no memory, don’t require primary antigen
What cells do NK cells target?
Pathogens/cells with reduced or absent MHC I signal
What can NK cells release if activated by MHC I expression?
IFN gamma
Perforin and granzyme
TNFa
What cells are activated by IFN gamma?
Macrophages, NK cells
What can activate NK cells?
IFN gamma
IL-2
Ab-opsonised Ag binding to Fc receptor
What is opsonisation?
Binding of an opsin (tag) to an invading cell - ‘prepare for eating’
Increase efficiency of phagocytosis
Increase no of binding sites
What is the complement cascade?
Biochemical cascade of plasma proteins
Trigger recruitment of immune cells
Opsonise pathogens
Aggregate forming membrane attack complex (through C3, C5 converts)
What are the 3 complement cascades?
Classical (Ag-Ab immune complex)
Lectin (mannose (bacterial polysaccharides)-binding to lectin)
Alternative (direct binding to microbe)
What is the difference between C3a and C3b?
C3b = large fragment, opsonin C3a = small fragment, pro-inflammatory
What forms the membrane attack complex?
C5b + C6 + C7 + C8 + C9
What is the function of the membrane attack complex?
Forms cytolytic pores which punches holes in cell membrane of target pathogens
List types of opsonins.
Plasma proteins
Ab
Complement
What do cytokines released in response to inflammation induce endothelial cells to produce for leukocyte adhesion?
Selectin
What is mast cell degranulation dependent on?
Cross linking of IgE Abs bound to Fc receptors on mast cell
What antibodies protect newborns in the first 6 months of life?
Maternally transferred IgG
How are immunodeficiencies classified?
Primary/congenital, secondary/acquired
What are patients with immunodeficiencies susceptible?
Infection
Cancer
Autoimmunity
What can be affected by primary immunodeficiencies?
Components of innate immune system
Stages of lymphocyte development
Response of mature lymphocytes to antigenic stimulation
List examples of congenital disorders that affect innate immune system.
Chronic granulomatous disease, leukocytes adhesion deficiency
What causes SCID?
Defects in T and B cells
If Serum Ig levels reduced, what type of deficiency does this suggest?
B cell deficiency
What changes are seen in follicles and germinal centres?
B cell deficiency - absent
T cell deficiency - normal
What does repeated infection with encapsulated bacteria a sign of?
Defective antibody production
If deficiency in IgG and IgA, what can this lead to?
Recurrent respiratory infection by pneumococcal or haemophilus spp.
What are infections with staph, gram -ve bacteria and fungi a sign of?
Reduced number of phagocytes
What defects can predispose to meningitis?
Complement defects
What do T cell/macrophage defects result in?
Predisposition to infection with protozoa, viruses, intracellular bacteria
What is reactivation of latent herpes virus?
T cell immunodeficiency
What does recurrent attacks of cold sores or shingles suggest?
Mild immunodeficiency (specifically T cell)
Give examples of herpes virus- induced tumours caused by T cell dysfunction.
Kaposi’s sarcoma
NHL
What pathway is likely to be defected with recurrent candida infections?
TH17
List causes of primary immunodeficiency.
Mutations Polymorphisms (two or more variants of a particular DNA sequence) Polygenic disorders (more than one gene involved)
List genetic causes of SCID?
Autosmal inherited
X-linked
What is a curative treatment for SCID?
Stem cell transplant (soon after birth)
What are common variable immunodeficiency (CVID) caused by?
Polygenic disorders - IgA deficiency
What does CVID cause?
Recurrent respiratory tract infections
What antibody fights fungal infections?
IgE
What do patients with APECED have a defect in?
Central tolerance
Produce antibodies against IL17
What do patients with APECED have an increased risk of?
Recurrent candida infections
How do you diagnose primary immune deficiency?
- Recurrent infections
- Unusual infections
- Family history of neonatal death
- Lymphocyte count (low)
- Flow cytometry for antibody count (IgG, IgE, IgM)
How do you treat primary immunodeficiency?
Prevent infection by... Prophylactic antibiotics If severe --> Immunoglobulin replacement therapy Stem cell transplant e.g for SCID Gene therapy
What are secondary causes of low antibodies?
Kidney or gut disease
When can you give gene therapy for primary immunodeficiency?
Gene mutation identified
Evidence correcting mutation will improve condition
Transfected gene must confer a d proliferative survival advantage
Must not cause malignancy
List 3 types of antigens that can cause hypersensitivity?
Infection
Harmless environmental substances
Self-antigen
Name a virus that can cause hypersensitivity reactions.
Influenza
damage endothelium –> exaggerated immune response –> trigger cytokine storm –> hypotension and coagulation
How does IgE get produced in hypersensitivity reactions?
Th2 –> IL-4 –> B cells –> IgE
List environmental factors that can trigger hypersensitivity.
Pollen
Dust
Food
Nickel (contact dermatitis)
What is the difference between IgE and IgG mediated hypersensitivities?
IgE –> immediate, allergy symptoms
IgG –> farmer’s lung
What are haptens?
Small molecules that bind to proteins and elicit and immune response.
Can’t bind to antibodies but bind to other small proteins,
What is a type 1 hypersensitivity reaction?
Allergy
Immediate reaction
IgE mediated
Mast cells and eosinophil degranulation
What is a type 2 hypersensitivity reaction?
Antibody mediated, on second exposure allergic reaction
What is a type 3 hypersensitivity reaction?
Immune complexes formed between antibodies and antigens
What is a type 4 hypersensitivity reaction?
Delayed hypersensitivity
What do Th2 cells induce?
Production of IgE from B cells via IL-4
Define atopy.
Immediate hypersensitivity rection to environmental antigens mediated by IgE
Develops within minutes of exposure
List signs of atopy.
Anaphylaxis Angioedema Urticaria Rhinitis Asthma Dermatitis
What is angioedema?
Non-specific, non-itchy swelling
What is the allergic march?
Development of allergic reactions over time
Define allergens.
Antigens that cause allergic reactions.
What is the allergen in penicillin allergies?
B-lactam
When do B cells produce IgE?
Co-stimulation with IL-4 secreted by Th2
What causes allergic symptoms?
Release of mediators that cause allergic symptoms
What cells degranulate causing allergic symptoms?
Mast cells
Eosinophils (migrate to tissues)
Basophils (stay in circulation)
What receptors are found on mast cells?
For IgE (regular and high affinity types)
What is a genetic cause of allergies?
Polymorphisms in gene encoding filaggrin which is expressed in keratocytes
What is the role of fillagrin?
Maintains epithelial barriers and moisturising surfaces and controlling pH
What are polymorphisms?
Slightly different alleles for same gene, present in 1% or more of population
List two polymorphism variants that can cause induction of Th2.
Filaggrin variant
LPS receptor variant
Why is the incidence of allergies increasing globally?
Urbanisation
Hygiene hypothesis
Discuss the pathophysiology of anaphylaxis.
Mast cells produce prostaglandins and leukotrienes through the cyclo-ocygenase and lipoxygenase pathways
–> vasodilation and increased vascular permeability –> shift of fluids from vascular to extra-vascular space –> drop in BP
Histamine in skin –> further increase shift of fluid (oedema)
Discuss the pathophysiology of rhinitis.
Inhaled allergens stimulates mast cells in nasal mucosa
Leukotrienes increase mucous secretion
How do you treat type 1 hypersensitivity reactions?
Desensitisation (allergy immunotherapy)
Drugs: B2-adrenergic agonists, adrenaline, antihistamines, leukotriene agionists, corticosteroids
What test can be carried out to identify cause of allergies?
Skin prick test
How does type 2 hypersensitivity reactions occur?
Antibody mediated - IgG (through complement) or IgM (through pathogen)
What is the most common type of type 2 hypersensitivity?
Haemolytic anaemia
List examples of immune mediated haemolysis.
Alloimmune haemolysis e.g incompatibility with ABO
Autoimmune haemolysis e.g induced by infection or drugs, autoantibodies produced by malignant B cells
Type 2 reactions against solid tissue e.g Goodpastures syndrome
Give an example of a condition which release antibodies that affect cell function.
Graves disease - Thyroid stimulated with autoantibody that binds into the TSH receptor
List examples of hypersensitivity type 2 diseases.
Autoimmune haemolytic anaemia Autoimmune thrombocytopenia purpura Pemphigus vulgaris Vasculitis caused by ANCA Myaesthenia gravis Penicious anaemia
What antibody is responsible for type 3 hypersensitivity reaction?
IgG
–> form antigen-antibody complex
(large complexes when antibody= antigen, when antibody>antigen = small complex)
In type 3 hypersensitivity reactions, what breaks down large complexes?
Complement
What causes immune complex disease in type 3 hypersensitive reactions?
Failure of clearance of complexes by complement
–> activation of innate immune system
Give an example of a type 3 hypersensitivity reaction with immune complex disease.
Glomerulonephritis
Farmer’s lung
SLE
What is the slowest type of hypersensitivity?
Type 4 (2-3 days)
What initiates type 4 hypersensitivity reactions?
Macrophages recognise ANTIGEN –> dendritic cells migrate to lymph nodes and present antigen to T cells –> exaggerated response against self antigen
What stimulates most of the damage in type 4 hypersensitivity?
TNF secreted by macrophages and T cells
Give examples of type 4 hypersensitivity reactions.
Rheumatoid arthritis Multiple sclerosis T1DM IBD Psoriasis
What helper T cells are associated with type 4 hypersensitivity reactions?
Th1 and 17
How do you treat delayed hypersensitivity?
Prevent through avoidance of antigens
Anti-inflammatories: NSAIDs, corticosteroids, drugs that block TNF and IL-6, Abs against B cells
Immunosuppressive drugs
Define immunological tolerance.
Unresponsiveness to an antigen that is induced by previous exposure to that antigen
What are tolerogens?
antigens that induce tolerance
What occurs from failure of self tolerance?
Autoimmunity
What are the two types of immunological tolerance?
Central - thymus, eliminate T cells with high affinity to self. Bone marrow for B cell tolerance
Peripheral - mature lymphocytes that recognise self in peripheral tissues become incapable of activation or die by apoptosis
List mechanisms of peripheral tolerance.
Anergy Antigen recognition with co-stimulation Treg suppression Deletion Some self antigens sequestered from immune system by anatomic barriers
Define autoimmunity.
Adaptive immune response to self antigens
Define autoantigens.
Antibodies directed at normal cellular components
autoimmune disease occurs when auto reactive T cells or autoantibodies cause tissue damage through what types of hypersensitivity?
2, 3, 4
What is the major source of autoantibodies?
B1 cells
–> cross-react with inherited A and B antigens of red cells, make IgM anti-A and anti-B even if not exposed
What causes breakdown of T cell tolerance?
Genetic predisposition (familial clustering, MHC alleles, polymorphisms, rare genetic diseases, AIRE gene)
Environmental factors (infections, drugs, UV radiation )
What gene can be mutated to prevent central tolerance from not taking place?
AIRE gene (transcription factor expressed by medullary epithelial cells in thymus)
What is molecular mimicry?
Structural similarity between self-proteins and microbial antigens may trigger an autoimmune response –> caused by infection, drugs
Most autoimmune diseases present age 15-65. Give an exception to this.
T1DM
What are the two different types of autoimmune disease.
Non-organ specific
Organ specific (endocrine gland)
Give examples of autoimmune diseases.
SLE
T1DM
Coeliac disease
How is autoimmune diseases treated?
suppress damage of immune response (immunosuppressives)
Replace function of organ damaged
e.g Treg cell therapies
What gender is autoimmune diseases most common in?
Females mostly
Define autograft.
Transfer of tissue between different sites within same organism.
Define isograft.
Transfer between genetically identical individuals
Define allograft.
Transfer between genetically non-identical individuals of same species
Define xenograft.
Transfer between species
What is the most common type of transplant?
Allograph
List two things to do to prevent transplant rejection.
Tissue match (ABO, HLA-A, B, DR) Prophylactic immunosuppressive therapy
Describe an instance when no tissue matching or immunosuppressive therapy is required.
Corneal transplant
Define privileged sites.
When no tissue typing or immunosuppression required
Can tolerate new antigens without inducing an immune response
List 7 complications of transplantation.
Graft rejection GVHD Infection Neoplasm Recurrence of original disease Drug side effects Ethical, surgical problems
List two mechanisms of graft rejection.
Direct alloantigen recognition or indirect presentation
*Mostly due to incomplete HLA matching
Define hyperacute rejection.
Minutes, from pre-formed Abs
Define accelerated rejection.
2-5 days, from T cells pre-sensitised
Define acute rejection.
7-21 days, from T cells newly sensitised
Define chronic rejection.
months-years, multifactorial
List 4 types of graft rejection.
Hyperacute, accelerated, acute, chronic
What is the most common cause of GVHD?
Bone marrow transplant
What circumstance need to be present to cause GVHD?
Presence of functioning immunocompetent donor T cells in graft
Defective immunity in recipient
HLA differences
Where is GVHD most commonly seen?
Skin, gut, liver and immune cells
How can GVHD by prevented?
Careful/v close tissue matching
Deplete donor marrow of T cells in vitro prior to grafting
Before bone marrow transplant, what should be done?
Conditioning - High dose chemo and radiotherapy (to destroy recipients SCs and allow engraftment of donor cells)
Give an example of an xenograft.
Porcine tisse
What is a problem with the use of porcine tissue?
Humans have naturally acquired IgM against pig Ags and galactose residues
Give examples of immunosuppressive drugs.
Cyclosporin Tacrolimus Basiliximab Rapamycin Azathioprine Methotrexate
List side effects of cyclosporin.
Nephrotoxic
Infections
DM
HTN
List side effects of the monoclonal antibody treatment Rapamycin.
Hyperlipidaemia/cholesterolaemia, HTN, Anaemia, Thrombocytopenia, acne
What is acute graft rejection associated with?
T cell responses that mediate immune cell infiltration into graft
What is IV immunoglobulin used for?
- Replacement therapy - primary and secondary immunodeficiencies
- Modulatory therapy - inflammatory and autoimmune disorders
What are potential problems with IVIg?
ADRs during infusions
Infection transmission e.g Hep C
List the two types of immunotherapy and give examples.
Direct (targeted) - Monoclonal Abs, CARs, Bi-specific Ab
Indirect - Tumour vaccines, dendritic cell therapies, cytokine therapies, checkpoint inhibitor therapies, stimulatory Abs
List established immunosuppressive/modulatory drugs.
Corticosteroids
Azathioprine
Cyclophosphamide
How do corticosteroids work?
affect B and T cells, cytokine network, inflammation, monocytes, transit and circulation of immunologically active cells
How does azathipoprine work?
inhibits DNA synthesis, T cells and NK cells, anti-inflammatory
How does cyclophosphamide
Suppress B cells and Ab production
List newer immunosuppressives.
Cyclosporin, Tacrolimus
Rapamycin
Mycophenolic acid
How do monoclonal antibody therapies work?
Target specific antigens e.g T cell receptors (CD3, 4 and 52, HLA, Cytokines)
Use mouse/rat derived AB, cleave Fc and replace with human Fc
Give 3 examples of monoclonal antibody therapies.
- Rituximab - NHL
- Inflixumab - RA, AS, IBD
- Trastuzumab/Herceptin - Breast cancer
How do cytokine therapies work?
Exert autocrine effects on cells or paracrine effects on cells around them
Involves production of factors that will interfere with cytokines or produce/administer recombinant cytokines
What is the purpose of cytokine therapy.
Inhibit harmful cytokines or enhance beneficial cytokines
Give examples of cytokine therapies.
IL-1/TNF - decrease activity in RA
IL-2 - Decrease activity in transplant rejection or increase in tumour therapy
What is the purpose of checkpoint inhibitors?
Unlock gateway to adoptive immune system - powerful anti-tumour response
What is a potential side effect of checkpoint inhibitors?
Immune related ADRs
Give an example of a checkpoint inhibitor for metastatic melanoma.
Ipilimumab
Discuss PD1/PDL-1 as targets for inhibitors.
In a cancer state, PD1 on T cell binds with PD-L1 on tumour cell causing reduced T cell function and therefore preventing immune system from attacking tumour.
If inhibit these checkpoints, then immune system can attack.
Give an example of an adoptive cell therapy.
CAR-T
