Q.1 What is the main role of the immune system in tissue regeneration?
To destroy new cells
To provide support for new tissue growth
To make the tissue larger
To remove all cells from the body
Explanation - The immune system helps by removing damaged cells and secreting signals that encourage new tissue to grow.
Correct answer is: To provide support for new tissue growth
Q.2 Which type of immune cell first arrives at a wound?
B cells
Neutrophils
T cells
Red blood cells
Explanation - Neutrophils are part of the innate immune response and are the first cells to migrate to injury sites.
Correct answer is: Neutrophils
Q.3 What does the word "inflammation" describe?
The process of blood clotting
An increase in temperature at the injury site
The body's reaction to injury or infection
The growth of new nerve cells
Explanation - Inflammation is a protective response involving redness, heat, swelling, and pain.
Correct answer is: The body's reaction to injury or infection
Q.4 Which cytokine helps recruit more immune cells to a damaged area?
Insulin
Tumor necrosis factor (TNF)
Estrogen
Adrenaline
Explanation - TNF is a signaling protein that attracts immune cells to sites of injury or infection.
Correct answer is: Tumor necrosis factor (TNF)
Q.5 Why is a clean wound site important for healing?
It keeps the patient warm
It reduces infection risk and supports immune regulation
It makes the scar look better
It helps the doctor see the wound better
Explanation - Cleaning removes bacteria that can trigger excessive inflammation and delay healing.
Correct answer is: It reduces infection risk and supports immune regulation
Q.6 Which part of the immune system recognizes specific pathogens?
Innate immunity
Adaptive immunity
Digestive system
Circulatory system
Explanation - Adaptive immunity uses specialized cells like B and T cells that recognize specific antigens.
Correct answer is: Adaptive immunity
Q.7 What do macrophages do in tissue repair?
Attack viruses
Eat dead cells and debris
Make bone
Produce hormones
Explanation - Macrophages clean up after injury and release growth signals for new tissue.
Correct answer is: Eat dead cells and debris
Q.8 Which protein helps blood cells stick together during clotting?
Hemoglobin
Fibrin
Collagen
Albumin
Explanation - Fibrin forms a mesh that stabilizes blood clots and keeps the wound closed.
Correct answer is: Fibrin
Q.9 What is the purpose of a scaffold in tissue engineering?
To taste like food
To act as a temporary structure for new cells to grow on
To make the tissue magnetic
To create a vacuum
Explanation - Scaffolds provide support and guidance for cells during tissue regeneration.
Correct answer is: To act as a temporary structure for new cells to grow on
Q.10 Which immune cell can become a ‘memory’ cell after infection?
Macrophage
Platelet
B cell
Red blood cell
Explanation - B cells can differentiate into memory B cells that remember a specific pathogen.
Correct answer is: B cell
Q.11 What happens if inflammation is too strong during healing?
The tissue heals faster
The tissue becomes infected
It can damage healthy tissue and delay healing
The wound turns blue
Explanation - Excessive inflammation can destroy new cells and prolong the healing process.
Correct answer is: It can damage healthy tissue and delay healing
Q.12 Which molecule signals the immune system to produce new blood vessels?
Insulin
Vascular endothelial growth factor (VEGF)
Melatonin
Glucose
Explanation - VEGF encourages blood vessel growth, which supplies nutrients for healing tissue.
Correct answer is: Vascular endothelial growth factor (VEGF)
Q.13 Why are T cells important for tissue regeneration?
They produce oxygen
They help regulate other immune cells and support healing
They create scar tissue
They store calcium
Explanation - Certain T cells release signals that guide inflammation and tissue repair.
Correct answer is: They help regulate other immune cells and support healing
Q.14 Which of these is a common symptom of chronic inflammation?
Rapid heartbeat
Pain and swelling that lasts long
Sharp vision
Sudden weight loss
Explanation - Chronic inflammation often causes persistent pain and swelling at the affected site.
Correct answer is: Pain and swelling that lasts long
Q.15 What is a 'biomaterial' used in regenerative medicine?
A type of metal
A natural or synthetic material that supports cell growth
An organ
A computer chip
Explanation - Biomaterials are designed to interact safely with the body to aid tissue repair.
Correct answer is: A natural or synthetic material that supports cell growth
Q.16 Which of these is NOT a typical immune cell involved in tissue regeneration?
Neutrophils
Erythrocytes
Macrophages
Fibroblasts
Explanation - Erythrocytes (red blood cells) mainly carry oxygen; they are not immune cells.
Correct answer is: Erythrocytes
Q.17 What does the term "immune privilege" mean?
The immune system is stronger in children
Certain body areas are protected from strong immune responses
The immune system can fight all diseases
The immune system works only in the skin
Explanation - Immune privilege refers to sites like the eye or brain where the immune response is limited to protect delicate tissues.
Correct answer is: Certain body areas are protected from strong immune responses
Q.18 Which immune pathway involves antibodies that recognize specific antigens?
Cell-mediated immunity
Humoral immunity
Innate immunity
Autoimmune immunity
Explanation - Humoral immunity uses antibodies produced by B cells to target specific antigens.
Correct answer is: Humoral immunity
Q.19 What is the primary function of cytokines during tissue repair?
To store energy
To act as signaling molecules that coordinate immune and healing responses
To form blood clots
To break down bone
Explanation - Cytokines communicate between cells, regulating inflammation, cell proliferation, and tissue remodeling.
Correct answer is: To act as signaling molecules that coordinate immune and healing responses
Q.20 Which type of T helper cell promotes macrophage activation during healing?
Th1
Th2
Th17
Treg
Explanation - Th1 cells secrete IFN-γ and other cytokines that activate macrophages, aiding in debris clearance.
Correct answer is: Th1
Q.21 Which cell type is primarily responsible for producing collagen during wound healing?
Fibroblasts
Erythrocytes
Neutrophils
Platelets
Explanation - Fibroblasts synthesize collagen fibers, forming the structural scaffold for new tissue.
Correct answer is: Fibroblasts
Q.22 What is the role of macrophage M2 phenotype in regeneration?
They increase inflammation
They release anti-inflammatory cytokines and support tissue remodeling
They attack foreign bodies
They become bone cells
Explanation - M2 macrophages promote healing by secreting IL-10 and growth factors that foster tissue repair.
Correct answer is: They release anti-inflammatory cytokines and support tissue remodeling
Q.23 Which signaling pathway is activated by IL-6 during inflammation?
JAK/STAT
MAPK
PI3K/AKT
Wnt/β-catenin
Explanation - IL-6 binds to its receptor, activating the JAK/STAT pathway that regulates gene expression in immune cells.
Correct answer is: JAK/STAT
Q.24 How does chronic inflammation affect tissue regeneration?
It speeds up scar formation
It promotes cell proliferation
It reduces fibroblast activity
It eliminates the need for immune cells
Explanation - Persistent inflammation can lead to excessive collagen deposition, resulting in scarring.
Correct answer is: It speeds up scar formation
Q.25 Which cell type is known for producing osteopontin during bone regeneration?
Chondrocytes
Osteoclasts
Osteoblasts
Fibroblasts
Explanation - Osteoblasts synthesize extracellular matrix proteins, including osteopontin, critical for bone formation.
Correct answer is: Osteoblasts
Q.26 What is the primary source of IL-10 in the immune response?
Treg cells
Neutrophils
Platelets
Red blood cells
Explanation - Regulatory T cells (Tregs) produce IL-10 to dampen inflammation and protect tissues.
Correct answer is: Treg cells
Q.27 Which cytokine is essential for recruiting neutrophils to an injury site?
IL-4
IL-8
TNF
IFN-γ
Explanation - IL-8 is a chemokine that attracts neutrophils to sites of inflammation.
Correct answer is: IL-8
Q.28 What is the role of the complement system in tissue repair?
It provides structural support
It opsonizes debris for macrophage clearance and can induce inflammation
It produces hormones
It stores calcium
Explanation - Complement proteins tag cells for removal and can amplify inflammatory signals.
Correct answer is: It opsonizes debris for macrophage clearance and can induce inflammation
Q.29 Which of the following best describes 'immune tolerance' in regenerative contexts?
The immune system is completely inactive
The immune response is balanced to avoid excessive damage while allowing repair
The immune system attacks all new cells
The immune system ignores foreign bodies
Explanation - Immune tolerance ensures that new tissue can grow without being destroyed by the immune system.
Correct answer is: The immune response is balanced to avoid excessive damage while allowing repair
Q.30 What is the main function of dendritic cells in tissue regeneration?
To produce bone
To act as antigen-presenting cells and initiate adaptive responses
To generate electrical signals
To store glycogen
Explanation - Dendritic cells capture antigens and present them to T cells, bridging innate and adaptive immunity.
Correct answer is: To act as antigen-presenting cells and initiate adaptive responses
Q.31 Which signaling pathway is activated by TGF-β during fibrosis?
JAK/STAT
SMAD
PI3K/AKT
Notch
Explanation - TGF-β binds its receptors, activating SMAD proteins that regulate extracellular matrix production.
Correct answer is: SMAD
Q.32 How does IL-17 contribute to regenerative processes?
By promoting angiogenesis and recruiting neutrophils
By reducing blood flow
By directly forming bone
By acting as an anti-inflammatory cytokine
Explanation - IL-17 stimulates the production of other cytokines and chemokines that support new blood vessel formation.
Correct answer is: By promoting angiogenesis and recruiting neutrophils
Q.33 Which of the following is a hallmark of M1 macrophage activity?
Production of IL-10
High expression of iNOS and release of pro-inflammatory cytokines
Release of collagen
Secretion of insulin
Explanation - M1 macrophages are pro-inflammatory, producing nitric oxide and cytokines like TNF and IL-1β.
Correct answer is: High expression of iNOS and release of pro-inflammatory cytokines
Q.34 What is the significance of the ECM (extracellular matrix) in tissue engineering?
It stores energy
It provides mechanical support and biochemical cues for cell adhesion, migration, and differentiation
It generates electrical currents
It functions as a hormone source
Explanation - The ECM serves as a scaffold and signaling platform that guides cell behavior during regeneration.
Correct answer is: It provides mechanical support and biochemical cues for cell adhesion, migration, and differentiation
Q.35 Which cell type can differentiate into multiple lineages during regeneration?
Neurons
Mesenchymal stem cells
Erythrocytes
Platelets
Explanation - Mesenchymal stem cells (MSCs) can become osteoblasts, chondrocytes, adipocytes, and other cell types.
Correct answer is: Mesenchymal stem cells
Q.36 What does the term 'phagocytosis' refer to?
Cell division
The engulfing and digestion of cellular debris or foreign particles by immune cells
The release of hormones
The synthesis of DNA
Explanation - Phagocytosis is a key function of macrophages and neutrophils in clearing damaged tissue.
Correct answer is: The engulfing and digestion of cellular debris or foreign particles by immune cells
Q.37 Which immunomodulatory strategy is commonly used to reduce scaffold rejection?
Applying heat treatment
Coating with anti-inflammatory peptides
Increasing oxygen levels
Using high-frequency electrical stimulation
Explanation - Surface modification with peptides such as RGD can minimize immune activation and improve biocompatibility.
Correct answer is: Coating with anti-inflammatory peptides
Q.38 Which cytokine is known to shift macrophages toward the M2 phenotype?
IL-1β
IL-4
TNF-α
IFN-γ
Explanation - IL-4 and IL-13 are key drivers that promote the anti-inflammatory M2 macrophage polarization.
Correct answer is: IL-4
Q.39 What is the main function of fibroblasts during the proliferative phase of wound healing?
They produce collagen and extracellular matrix components
They fight infections
They break down blood clots
They generate electrical impulses
Explanation - Fibroblasts synthesize collagen and glycosaminoglycans essential for tissue strength and repair.
Correct answer is: They produce collagen and extracellular matrix components
Q.40 Which of the following is a typical consequence of an inadequate immune response during tissue repair?
Rapid healing with no scar
Infection and delayed healing
Immediate bone formation
No effect at all
Explanation - Without proper immune action, pathogens can proliferate, causing infections that impede repair.
Correct answer is: Infection and delayed healing
Q.41 What role do platelets play in the early stages of tissue repair?
They produce antibodies
They release growth factors and cytokines that modulate inflammation and recruit cells
They form new bone directly
They cause blood clotting only
Explanation - Platelets release VEGF, PDGF, and other mediators that initiate healing processes.
Correct answer is: They release growth factors and cytokines that modulate inflammation and recruit cells
Q.42 Which of the following best describes 'angiogenesis' in the context of regeneration?
The removal of dead cells
The formation of new blood vessels
The breakdown of extracellular matrix
The generation of immune cells
Explanation - Angiogenesis supplies oxygen and nutrients, essential for new tissue growth and remodeling.
Correct answer is: The formation of new blood vessels
Q.43 In tissue engineering, what is the purpose of using a 'hydrogel' scaffold?
To provide electrical conductivity
To mimic the natural extracellular matrix with high water content and support cell infiltration
To serve as a source of nutrients
To reduce blood flow
Explanation - Hydrogels offer a hydrated, biocompatible environment conducive to cell proliferation and differentiation.
Correct answer is: To mimic the natural extracellular matrix with high water content and support cell infiltration
Q.44 What is the main difference between innate and adaptive immunity regarding tissue regeneration?
Innate immunity is slower to respond but more specific
Adaptive immunity responds immediately to all injuries
Innate immunity is a rapid, non-specific response, while adaptive immunity is slower but specific and memory-forming
Both have identical functions
Explanation - Innate immunity provides the first line of defense, whereas adaptive immunity tailors responses to specific antigens.
Correct answer is: Innate immunity is a rapid, non-specific response, while adaptive immunity is slower but specific and memory-forming
Q.45 Which molecule is primarily responsible for the 'stop' signal to neutrophils in resolving inflammation?
IL-10
Lipid mediators like resolvins
TNF-α
IL-2
Explanation - Resolvins and lipoxins help terminate neutrophil recruitment, allowing the healing process to proceed.
Correct answer is: Lipid mediators like resolvins
Q.46 How does TGF-β influence fibroblast activity during scar formation?
It inhibits collagen production
It promotes fibroblast proliferation and collagen synthesis, leading to scar tissue
It dissolves collagen
It has no effect
Explanation - TGF-β is a key regulator that encourages fibroblasts to produce extracellular matrix components.
Correct answer is: It promotes fibroblast proliferation and collagen synthesis, leading to scar tissue
Q.47 Which cell type is directly involved in bone remodeling after injury?
Chondrocytes
Osteoclasts
Epithelial cells
Neurons
Explanation - Osteoclasts resorb bone tissue, allowing for new bone formation by osteoblasts during regeneration.
Correct answer is: Osteoclasts
Q.48 What is the main role of IL-12 in the context of tissue repair?
It promotes anti-inflammatory responses
It stimulates Th1 cell differentiation and IFN-γ production
It acts as a growth factor for fibroblasts
It directly forms collagen
Explanation - IL-12 is pivotal for activating cell-mediated immunity, influencing macrophage activity during healing.
Correct answer is: It stimulates Th1 cell differentiation and IFN-γ production
Q.49 What does the 'resolution phase' of inflammation entail?
Continuation of high cytokine levels
Active removal of inflammatory cells, restoration of tissue homeostasis, and scar remodeling
Complete elimination of immune cells
Immediate tissue regeneration with no scar
Explanation - During resolution, the body clears debris, reduces inflammation, and prepares for remodeling.
Correct answer is: Active removal of inflammatory cells, restoration of tissue homeostasis, and scar remodeling
Q.50 Which immunological marker is often used to identify M2 macrophages?
CD68
CD206
CD3
CD4
Explanation - CD206 (mannose receptor) is a surface protein expressed on anti-inflammatory, reparative macrophages.
Correct answer is: CD206
Q.51 Which process is crucial for the formation of new bone after a fracture?
Osteoclast activity only
Osteoblast activity only
Coupled action of osteoclasts and osteoblasts
Neutrophil activity only
Explanation - Bone remodeling requires resorption by osteoclasts and new matrix deposition by osteoblasts.
Correct answer is: Coupled action of osteoclasts and osteoblasts
Q.52 Which of the following is an example of a bioactive molecule used to enhance angiogenesis in tissue engineering?
PDGF
VEGF
Insulin
Erythropoietin
Explanation - VEGF stimulates the growth of new blood vessels, which is essential for delivering nutrients to regenerating tissue.
Correct answer is: VEGF
Q.53 What is the significance of 'immune checkpoints' in tissue regeneration?
They stop blood flow
They regulate immune activation to prevent excessive inflammation and autoimmunity during healing
They generate new blood cells
They produce bone minerals
Explanation - Immune checkpoints like PD-1/PD-L1 help maintain a balanced response, preventing damage to healthy tissue.
Correct answer is: They regulate immune activation to prevent excessive inflammation and autoimmunity during healing
Q.54 What is the role of regulatory T cells (Tregs) during tissue regeneration?
To produce cytokines that amplify inflammation
To produce IL-10 and TGF-β, suppressing excessive immune responses and promoting tissue repair
To break down extracellular matrix
To directly form bone tissue
Explanation - Tregs secrete anti-inflammatory cytokines that help create a permissive environment for regeneration.
Correct answer is: To produce IL-10 and TGF-β, suppressing excessive immune responses and promoting tissue repair
Q.55 Which type of collagen is most abundant in scar tissue?
Type I
Type II
Type III
Type IV
Explanation - Type III collagen is typically overproduced during early wound healing and contributes to scar formation.
Correct answer is: Type III
Q.56 What is the primary function of the chemokine CXCL12 in stem cell homing?
To attract neutrophils
To attract stem cells to the injury site
To inhibit fibroblast proliferation
To break down ECM
Explanation - CXCL12 (SDF-1) guides stem cells to sites needing regeneration through chemotaxis.
Correct answer is: To attract stem cells to the injury site
Q.57 Which surface modification can reduce macrophage activation on a biomaterial?
Coating with polyethylene glycol (PEG)
Adding metal ions
Increasing roughness
Decreasing oxygen levels
Explanation - PEG creates a hydrophilic, non-adhesive surface that limits protein adsorption and macrophage attachment.
Correct answer is: Coating with polyethylene glycol (PEG)
Q.58 Which immunological process involves the presentation of extracellular antigens on MHC class II molecules?
MHC class I presentation
MHC class II presentation
Antibody production
T cell receptor signaling
Explanation - MHC II presents extracellularly derived peptides to helper T cells, crucial for adaptive immune regulation.
Correct answer is: MHC class II presentation
Q.59 How does IL-1β influence the inflammatory response during tissue repair?
It inhibits neutrophil recruitment
It promotes vasodilation, fever, and recruitment of immune cells
It directly repairs DNA
It induces apoptosis in all cells
Explanation - IL-1β is a potent pro-inflammatory cytokine that facilitates the influx of inflammatory cells.
Correct answer is: It promotes vasodilation, fever, and recruitment of immune cells
Q.60 What is the primary mechanism by which TGF-β promotes fibroblast-to-myofibroblast differentiation?
Activation of PI3K/AKT pathway
Activation of SMAD signaling pathway
Inhibition of SMAD signaling
Activation of JNK pathway
Explanation - TGF-β signals through SMAD proteins, driving myofibroblast differentiation and collagen deposition.
Correct answer is: Activation of SMAD signaling pathway
Q.61 Which of the following best describes 'immune privilege' in ocular tissue regeneration?
The eye produces antibodies in excess
The eye actively suppresses immune responses to protect vision
The eye has no blood supply
The eye does not involve immune cells
Explanation - The eye employs mechanisms to limit immune activation, preserving delicate neural tissue.
Correct answer is: The eye actively suppresses immune responses to protect vision
Q.62 Which cell type releases platelet-derived growth factor (PDGF) to aid in wound healing?
Neutrophils
Platelets
T cells
B cells
Explanation - Platelets store and release PDGF, promoting fibroblast proliferation and ECM production.
Correct answer is: Platelets
Q.63 What is the primary consequence of an uncontrolled macrophage M1 response in chronic wounds?
Accelerated tissue regeneration
Suppression of angiogenesis and tissue remodeling
Formation of hair follicles
No effect on healing
Explanation - Persistent M1 macrophage activity can hinder new vessel growth and impede healing.
Correct answer is: Suppression of angiogenesis and tissue remodeling
Q.64 Which immunological pathway is most important for initiating a specific response to a biomaterial implant?
Complement activation
Adaptive T cell response
Innate cytokine release
Neuronal signaling
Explanation - The adaptive immune system can recognize implant antigens, leading to a specific, sometimes chronic, response.
Correct answer is: Adaptive T cell response
Q.65 What is a key advantage of using decellularized extracellular matrix (dECM) scaffolds in regenerative medicine?
They provide electrical stimulation
They remove cellular antigens while preserving native ECM components, reducing immune rejection
They are made from synthetic polymers only
They increase oxygen consumption
Explanation - Decellularization leaves behind structural proteins that support cell attachment and limit immune activation.
Correct answer is: They remove cellular antigens while preserving native ECM components, reducing immune rejection
Q.66 What is the primary role of the protein NF-κB in the context of tissue regeneration?
It acts as a structural protein
It regulates the expression of pro-inflammatory genes, influencing the early stages of healing
It degrades collagen
It provides electrical conduction
Explanation - NF-κB is a transcription factor that drives cytokine production and immune cell recruitment.
Correct answer is: It regulates the expression of pro-inflammatory genes, influencing the early stages of healing
Q.67 Which signaling axis is critical for coordinating macrophage polarization and fibrosis during chronic inflammation?
Wnt/β-catenin
TGF-β/SMAD
Notch/Delta
Hippo/YAP
Explanation - TGF-β signaling through SMADs promotes fibroblast activation and extracellular matrix deposition.
Correct answer is: TGF-β/SMAD
Q.68 What therapeutic strategy can modulate the immune microenvironment to enhance cartilage regeneration?
Blocking IL-6 signaling with monoclonal antibodies
Increasing IL-10 expression via gene delivery
Inhibiting all immune responses
Stimulating osteoclast activity
Explanation - Elevated IL-10 reduces inflammation and supports chondrocyte survival and matrix synthesis.
Correct answer is: Increasing IL-10 expression via gene delivery
Q.69 Which immune checkpoint molecule is upregulated on T cells during prolonged tissue injury, potentially dampening regeneration?
PD-1
CTLA-4
CD28
CD69
Explanation - PD-1 expression increases during chronic inflammation, limiting T cell activity and affecting repair.
Correct answer is: PD-1
Q.70 In the context of bioengineered vascular grafts, which cytokine is most implicated in endothelialization and anti-thrombogenic properties?
IL-12
VEGF
TNF-α
IFN-γ
Explanation - VEGF promotes endothelial cell growth and function, essential for graft integration and preventing clotting.
Correct answer is: VEGF
Q.71 What is the functional consequence of sustained IL-1β signaling in chronic wounds?
Enhanced fibroblast migration
Persistent inflammation leading to impaired healing and tissue breakdown
Accelerated collagen crosslinking
Complete resolution of inflammation
Explanation - Long-term IL-1β activity sustains inflammation, causing tissue degradation and delayed repair.
Correct answer is: Persistent inflammation leading to impaired healing and tissue breakdown
Q.72 Which of the following best describes 'immune exhaustion' in the context of prolonged tissue injury?
Overactivation of immune cells leading to tissue damage
Loss of functional activity of T cells due to chronic antigen exposure
Complete absence of immune cells
Rapid regeneration of immune cells
Explanation - Immune exhaustion impairs the adaptive response, potentially compromising effective tissue repair.
Correct answer is: Loss of functional activity of T cells due to chronic antigen exposure
Q.73 What role does the protein S100A8/A9 play in tissue regeneration?
They inhibit angiogenesis
They act as damage-associated molecular patterns (DAMPs) that amplify inflammation
They directly form new bone
They are structural proteins in collagen
Explanation - S100A8/A9 released from damaged cells can recruit neutrophils and exacerbate inflammation.
Correct answer is: They act as damage-associated molecular patterns (DAMPs) that amplify inflammation
Q.74 Which immunomodulatory approach is used to reduce fibrotic scarring in engineered skin grafts?
Administration of TGF-β inhibitors
Use of high-dose antibiotics
Increasing neutrophil infiltration
Suppressing macrophage recruitment
Explanation - Blocking TGF-β activity mitigates excessive collagen deposition and scarring.
Correct answer is: Administration of TGF-β inhibitors
Q.75 What is the main benefit of incorporating IL-4 into a hydrogel for soft tissue repair?
To promote M1 macrophage activation
To shift macrophage polarization towards M2 phenotype, enhancing anti-inflammatory and repair pathways
To inhibit fibroblast proliferation
To increase neutrophil migration
Explanation - IL-4 drives M2 polarization, which supports tissue remodeling and reduces inflammation.
Correct answer is: To shift macrophage polarization towards M2 phenotype, enhancing anti-inflammatory and repair pathways
Q.76 Which of the following best explains the concept of 'immune education' in the design of biomaterials?
Teaching biomaterials to produce electricity
Modifying biomaterial surfaces to present specific peptides that train the immune system toward tolerance rather than rejection
Using biomaterials to generate new immune cells
Inserting foreign DNA into immune cells
Explanation - Immune education aims to shape the immune response to be compatible with the implanted material.
Correct answer is: Modifying biomaterial surfaces to present specific peptides that train the immune system toward tolerance rather than rejection
Q.77 Which immunological marker is commonly used to assess the degree of chronic inflammation in a tissue biopsy?
CD45
CK18
S100
CD31
Explanation - CD45 is a pan-leukocyte marker, indicating the presence of infiltrating immune cells.
Correct answer is: CD45
Q.78 Which pathway is primarily responsible for the anti-inflammatory effects of glucocorticoids during tissue repair?
NF-κB inhibition
PI3K/AKT activation
JAK/STAT activation
MAPK activation
Explanation - Glucocorticoids suppress NF-κB signaling, reducing pro-inflammatory gene expression.
Correct answer is: NF-κB inhibition
Q.79 Why is the timing of anti-inflammatory therapy critical in tissue regeneration?
Because early suppression may hinder essential inflammatory signaling needed for debris clearance and recruitment of regenerative cells
Because late suppression causes excessive inflammation
Because inflammation is irrelevant to regeneration
Because timing does not affect outcomes
Explanation - Inflammation initiates healing; premature suppression can delay or impair regeneration.
Correct answer is: Because early suppression may hinder essential inflammatory signaling needed for debris clearance and recruitment of regenerative cells