immunology final
Which cells are the first responders during acute inflammation?
Neutrophils
Toll-like receptors recognize:
PAMPs (conserved pathogen patterns), trigger innate activation
Which cell type releases histamine during allergic reactions?
Mast cells
Which complement protein is a major opsonin?
C3b
NK cells kill target cells that:
Lack MHC 1
Which molecule is an anaphylatoxin?
C5a
Interferon-α is primarly produced in response to:
Viruses
Defensins are:
Antimicrobial peptides
The oxidative burst in neutrophils requires:
NADPH oxidase
Which is a professional antigen-presenting cell?
Dendritic cell
Mannose-binding lectin activates which complement pathway?
Lectin
The major function of macrophages is:
Phagocytosis and cytokine release
Which cytokine activates macrophages?
IFN-γ
Which cell type produces type I interferons?
Virus-infected cells
Which receptor recognizes LPS on gram-negative bacteria?
TLR4
Which cells forms pus?
Neutrophils
C-reactive protein (CRP) promotes:
Opsonization
Which chemokine attracts neutrophils?
IL-8
Dendritic cells migrate to lymph nodes via:
Lymphatic vessels
Which complement pathway is antibody-dependent?
Classical
Which immune cells release major basic protein?
Eosinophils
Which organ filters bloodborne pathogens?
Spleen
Which cytokine causes septic shock?
TNF-α, due to massive vasodialation
Which cell bridges innate and adaptive immunity?
Dendritic cell
Which cell is most effective in killing helminths?
Eosinophils
Which innate cell presents antigen via MHC II?
Macrophages
What do PRRs (pattern recognition receptors) detect?
PAMPs (pathogen molecular patterns)
Which complement protein is most important for opsonization?
C3b
Which cells kill virally infected cells without prior sensitization?
NK cells
What triggers the alternative complement pathway?
Pathogen surfaces
Which molecule mediates leukocyte rolling?
Selectins
What is the main component of NETs (neutrophils extracellular traps)?
DNA
What is a pro-inflammatory cytokine?
IL-6
Acute phase proteins are produced by the:
Liver
Which innate cell presents lipid antigens on CD1 molecules?
Dendritic cells
IFN-γ is produced mainly by:
NK cells and T cells
Which cells release histamine in response to C3a and C5a?
Mast cells
Which phagocyte is long-lived?
Macrophage
Which cells produce antibodies?
B-cells that differentiate into Plasma cells
CD8+ T cells recognize antigen presented on:
MHC I
Which antibody is produced first in a primary response?
IgM
Which enzyme mediates V(D)J recombination:
RAG1/2
Which antibody class crosses the placenta?
IgG
T-cell maturation occurs in the:
Thymus
Class-switch recombination requires which enzyme?
AID
Th1 cells activate:
Macrophages
Th2 cells activate:
Eosinophils for parasites/allergies
IgA is most associated with:
Mucosal immunity
Which immunoglobulin is pentameric?
IgM
MHC II presents peptides from:
Extracellular proteins
Which cells activate naive T cells?
Dendritic cells
Which cytokine is key for Th17 differentiation?
IL-6
Regulatory T (Tregs) cells suppress immunity using:
IL-10 and TGF-β
Memory B cells allow for:
Faster and stronger response
Somatic hypermutation occurs in the:
Germinal center
Which molecule provides costimulation (secondary activation signal) to T-cells?
CD80/86
Affinity maturation increases:
Antibody binding strength
Anergy (T-cell unresponsiveness) results from
Lack of costimulation
Which cells kill virus-infected cells in adaptive immunity?
CD8+ T cells
Thymic positive selection ensures T cells:
Can bind self-MHC
Thymic negative selection eliminates T cells that:
Bind foreign antigens
Which cytokine is essential for T-cell proliferation?
IL-2
Which antibody neutralizes toxins?
IgG
CD4 binds to:
MHC II β2 domain
what is an epitope?
The specific part of antigen recognized by antibodies
Cross-presentation allows dendritic cells to present:
Extracellular antigens on MCH I
IL-4 promotes which antibody isotype?
IgE
CD28 on T cells binds to:
CD80 and CD86
Which antibody is associated with allergic reactions?
IgE
Naive B cells express:
IgM and IgD
Which cytokine drives Th1 differentiation?
IL-12
Th17 cells are important for defense against:
Extracellular bacteria and fungi
Which cells are essential for germinal center formation?
T follicular helper cells
Which processes require AID?
Class switch & somatic hypermutation
IgG is most effective in:
Neutralization and opsonization
What is clonal selection?
Expansion of lymphocytes that bind antigen
What cytokine activates CD8+ T cells?
IL-12
What is central tolerance?
Elimination of self-reactive lymphocytes in thymus/bone marrow
Which cell type kills cells via perforin and granzyme?
CD8+ T cells
What is required for T-cell activation?
Antigen + costimulation
What is peripheral tolerance?
control of self-reactive cells outside primary organs
which isotypes can activate complement?
IgM and IgG
what is the purpose of the thymus?
T-cell development
T-cell receptor recognizes:
Peptide-MHC complexes
Which antibody is dimeric in secretions?
IgA
Which T cells help activate B cells?
Tfh (follicular helper) cells
Which cytokine inhibits immune responses?
IL-10
Plasma cells primarily reside in the:
Spleen and lymph nodes
Type I hypersensitivity reactions are mediated by:
IgE
Anaphylaxis is an example of:
Type I
Type II hypersensitivity involves:
IgG/IgM binding to cell surfaces
Serum sickness is which type of hypersensitivity?
Type III
Contact dermatitis is mediated by:
T cells
Graves disease is caused by antibodies that:
Stimulate TSH receptors
Myasthenia gravis results from antibodies that:
Block acetylcholine receptors
Immune complexes deposit in tissues in which hypersensitivity?
Type III
Tuberculin skin testing is:
Type IV
Rheumatoid arthritis is mainly:
Type III and IV
Which hypersensitivity involves complement activation on cell membranes?
Type II
Lupus is primarliy associated with:
Immune complex deposition
Anti-dsDNA antibodies are found in:
Systemic lupus erythematosus
Hashimoto thyroiditis involves:
Antibody-mediated thyroid destruction
Goodpasture syndrome targets which tissues?
Kidney and lungs
Type IV hypersensitivity occurs after:
Days
Autoimmunity may result from:
Loss of self-tolerance
Celiac disease is caused by T-cell response to:
Gluten
Molecular mimicry occurs when:
Pathogen antigens resemble human proteins
Which cytokine drives chronic autoimmune inflammation?
TNF-α
Which hypersensitivity features wheals and flares?
Type I
Hemolytic transfusion reactions are:
Type II
Immune complex deposition in glomeruli indicates:
Type III
Multiple sclerosis affects the:
Myeline of CNS
Autoantibodies against intrinsic factor cause:
Pernicious anemia
Atopic asthma is mediated by:
IgE
Chronic transplant rejection is mediated by:
T-cells and macrophages
Which hypersensitivity is mediated ONLY by T cells?
Type IV hypersensitivity
Anti-CCP (cyclic citrullinated peptide) antibodies appear in:
Rheumatoid arthritis
What cell types drives Type IV hypersensitivity?
CD4+ T cells
Immune thromocytopenic purpura (ITP) is:
Type II
Asthma is associated with increased:
IgE
Guillain-Barre Syndrome (GBS) is triggered by:
Molecular mimicry
Autoimmune hemolytic anemia is mediated by:
Antibodies against RBCs
What mediates damage in Type III hypersensitivity?
Immune complexes
Epitope spreading refers to:
Broader autoreactive responses over time
Which hypersensitibity uses Fc receptors on macrophages?
Type II hypersensitivity
What drives granuloma formation?
Th1 cells
Which illness is associated with anti-histone antibodies?
Drug-induced lupus
Food allergies are:
Type I hypersensitivity
Autoimmune disease more common in women because of?
Hormonal and genetic factors
HLA-B27 is associated with:
Ankylosing spondylitis
PPD (purified protein derivative) test is a:
Type IV, tests for TB
Stevens-Johnson syndrome involves:
T-celll mediated cytotoxicity
In Type II hypersensitivity complement leads to:
Tolerance
Autoimmune disease often involve elevated:
IL-6
Pemphigus vulgaris involves antibodies against:
Desmosomes
Vasculitis in Type III hypersensitivity results from:
Immune complexes
Chronic autoimmune diseases often involve:
Macrophages and Th1 cells
Autoimmune diseases commonly involve:
Loss of self-tolerance
X-linked agammaglobulinemia involves failure of:
B-cell maturation
ADA (Adenosine Deaminase) deficiency leads to:
SCID (Severe Combined Immune Deficiency)
DiGeorge syndrome results from failure of:
Thymus
Chronic granulomatous disease is caused by defective:
NADPH oxidase
Complement C5-C9 deficiency leads to infections with:
Neisseria
Selective IgA deficiency cause:
Mucosal infections
Hyper-IgM syndrome results from failure of:
Class-switching
Wiskott-Aldrich syndrome includes:
Eczema infections thromocytopenia
SCID patients lack:
Both T and B cells
Splenectomy increases risk of infection by:
Encapsulated bacteria
HIV infects:
CD4+ T cells
Leukocyte adhesion deficiency affects:
Integrins
C3 deficiency increases susceptibility to:
Encapsulated bacteria
X-linked agammaglobulinemia (XLA) presents with:
Low all immunoglobulins
HIV reduces immunity by:
CD4 T-cell destruction
Ataxia-telangiectasia involves:
DNA repair defects
Chronic mucocutaneous candidiasis results from defective:
T-cell response
Job syndrome (Hyper-IgE) causes:
High Ige and eczema
Complement C1 inhibitor deficiency causes:
Hereditary angioedema
Neutropenia increases susceptibility to:
Bacterial infections
NK cell deficiency leads to:
Viral infections
Hyper-IgM syndrome is due to:
CD40L deficiency
SCID patients require:
Bone marrow transplant
People without a spleen lack:
Marginal zone B cells
HIV binds to:
CD4 and CCR5/CXCR4
Hyper-IgE syndrome results in impaired:
Neutrophil chemotaxis
Paroxysmal nocturnal hemoglobinuria results from:
Complement overactivation
Patients with MCH II deficiency lack:
CD4 T-cell activation
Chronic granulomatous disease leads to susceptibility to:
Catalase-positive bacteria
Complement deficiencies typically cause:
Recurrent infections
Live attenuated vaccines provide:
Strong lifelong immunity
Inactivated vaccines induce mainly:
Humoral immunity
Toxoid vaccines protect against:
Bacterial toxins
Conjugate vaccines link polysaccharides to :
Protein carriers
Which vaccine is live?
MMR (Measles, Mumps, Rubella)
Hyperacute transplant rejection is mediated by:
Performed antibodies
Acute graft rejection involves:
T-cells
Graft-versus-host disease occurs when:
Donor T cells attack host
Autografts come from:
Self
Calcineurin inhibitors block:
IL-2 production
Checkpoint inhibitors block:
PD-1/PD-L1 or CTLA-4
CAR-T therapy involves engineering:
T cells to target tumors
Tumor antigens are presented on:
MHC molecules
NK cells kill tumor cells by recognizing:
Low MHC I
Dendritic cell vaccines work by:
Presenting tumor antigens to T cells
Chronic transplant rejection is mediated by:
T cells and fibrosis
What cytokine stimulates NK cells?
IL-12
Monoclonal antibodies treat cancer by:
Targeting tumor antigens
PD-1 helps cancer cells by:
Inhibiting T cells
What molecule is commonly targeted in immunotherapy?
PD-L1
Tumor-infiltrating lymphocytes are:
T cells inside tumors
Cytokine-release syndrome in CAR-T therapy is due to:
Excess IL-6
CTLA-4 (cytotoxic T-Lymphocyte Antigen 4) inhibits:
T-cell activation
Hyperacute rejection occurs:
Minutes after transplantation
Cancer immune editing refers to:
Tumors mutating to escape immunity
what cells mediate ADCC (antibody-dependent cellular cytotoxicity)?
NK cells
Allografts come from:
Donors
Tumors escape immunity by:
Downregulating MHC I
Which vaccine requires booster shots?
Inactivated vaccines
Bispecific antibodies can:
bind two different antigens simultaneously
Which cytokine causes fever?
IL-1
The membrane attack complex is formed by which complement component?
C9
Which cell type releases histamine during allergic reactions?
Mast cells
Which cells kill tumor cells without prior sensitization?
NK cells
Tumor-specfic antigens are:
Uniquely expressed on tumor cells
Tumors evade immune detection by:
Secreting PD-L1
CD8 T cells recognized tumor cells through:
MHC I
Which is a checkpoint inhibitor?
Anti-PD-1 antibody
Tumor-associated antigens are:
normal proteins abnormally expressed
Which cells contribute to tumor immune suppression?
Tregs
CAR-T therapy involves engineering
T cells
Tumors evade surveillance by downregulating:
MHC I
Which cytokine enhances anti-tumor immunity?
IL-2
CTLA-4 functions to:
Suppress T cell activation
Tumor immunoediting phases include elimination, equilibrium, and:
Escape
ADCC occurs when:
NK cells recognize Fc of IgG
Tumor cells secreting VEGF cause:
Angiogenesis
Oncolytic viruses:
Kill tumor cells & stimulate immunity
Cold tumors are:
Low immune infiltration:
Tumor infiltrating lymphocytes are:
T cells in tumors
Tumors induce tolerance by:
Secreting IL-10 and TGF-β
Checkpoint blockade enhances:
T cell anti-tumor activity
Acute phase proteins are produced by the:
Liver