Q.1 Which of the following cells are primarily responsible for immune surveillance in the central nervous system (CNS)?
Astrocytes
Microglia
Oligodendrocytes
Neurons
Explanation - Microglia are the resident macrophages of the CNS and play a critical role in immune surveillance and response to injury or infection.
Correct answer is: Microglia
Q.2 The blood-brain barrier (BBB) mainly consists of:
Astrocytic end-feet and endothelial cells
Microglia and neurons
Oligodendrocytes and astrocytes
Ependymal cells and neurons
Explanation - The BBB is formed by tight junctions between endothelial cells and is supported by astrocytic end-feet, which regulate the passage of molecules into the CNS.
Correct answer is: Astrocytic end-feet and endothelial cells
Q.3 Which cytokine is predominantly associated with neuroinflammation in multiple sclerosis?
IL-4
IL-10
TNF-α
TGF-β
Explanation - TNF-α is a pro-inflammatory cytokine that plays a central role in mediating neuroinflammation in diseases like multiple sclerosis.
Correct answer is: TNF-α
Q.4 Oligodendrocytes are primarily responsible for:
Producing cerebrospinal fluid
Forming myelin in the CNS
Phagocytosing pathogens
Maintaining the BBB
Explanation - Oligodendrocytes produce myelin sheaths that insulate CNS axons, facilitating rapid electrical signal transmission.
Correct answer is: Forming myelin in the CNS
Q.5 Which of the following molecules is a key chemokine involved in recruiting immune cells to the CNS during inflammation?
CCL2
Glutamate
Acetylcholine
Dopamine
Explanation - CCL2 (also called MCP-1) attracts monocytes and other immune cells to sites of CNS inflammation.
Correct answer is: CCL2
Q.6 The gut-brain axis involves communication between the CNS and:
Peripheral immune system
Gastrointestinal microbiota
Both A and B
Skeletal muscles
Explanation - The gut-brain axis represents bidirectional communication between the CNS, the gut microbiota, and peripheral immune responses, influencing neuroimmunology.
Correct answer is: Both A and B
Q.7 Which neurodegenerative disease is linked to abnormal activation of microglia?
Alzheimer's disease
Parkinson's disease
Multiple sclerosis
All of the above
Explanation - Microglial activation contributes to neuroinflammation, which is implicated in multiple neurodegenerative diseases, including Alzheimer's, Parkinson's, and MS.
Correct answer is: All of the above
Q.8 Astrocytes contribute to neuroimmunity by:
Secreting cytokines and chemokines
Forming myelin
Conducting action potentials
Producing neurotransmitters only
Explanation - Astrocytes regulate the immune environment in the CNS by releasing cytokines and chemokines that modulate inflammation and repair.
Correct answer is: Secreting cytokines and chemokines
Q.9 Which of the following is a hallmark of neuroinflammation?
Infiltration of peripheral immune cells
Glial cell activation
Cytokine release
All of the above
Explanation - Neuroinflammation involves glial cell activation, peripheral immune cell infiltration, and cytokine release, collectively impacting CNS function.
Correct answer is: All of the above
Q.10 Which molecule serves as a primary immune checkpoint in the CNS?
PD-1/PD-L1
IL-2
Acetylcholine
Dopamine
Explanation - PD-1/PD-L1 signaling regulates immune responses in the CNS, maintaining immune homeostasis and preventing excessive inflammation.
Correct answer is: PD-1/PD-L1
Q.11 Which type of T cell is most commonly associated with CNS autoimmunity?
CD8+ cytotoxic T cells
CD4+ Th1 and Th17 cells
Regulatory T cells
Memory B cells
Explanation - CD4+ Th1 and Th17 cells mediate pro-inflammatory responses in autoimmune conditions like multiple sclerosis.
Correct answer is: CD4+ Th1 and Th17 cells
Q.12 The glymphatic system is involved in:
Immune cell production
Waste clearance from the CNS
Synaptic transmission
Myelination
Explanation - The glymphatic system facilitates the clearance of metabolic waste, including immune complexes, from the CNS via cerebrospinal fluid.
Correct answer is: Waste clearance from the CNS
Q.13 Which immune molecule is implicated in synaptic pruning by microglia?
C1q
IL-6
TNF-α
CCL5
Explanation - C1q, part of the complement system, tags synapses for elimination by microglia during development and in disease states.
Correct answer is: C1q
Q.14 Peripheral infections can influence CNS immunity primarily through:
Direct infection of neurons
Activation of systemic cytokines
Destruction of myelin
Axonal degeneration only
Explanation - Peripheral infections lead to cytokine production that can cross or signal through the BBB, influencing CNS immune responses.
Correct answer is: Activation of systemic cytokines
Q.15 Which of the following is NOT a component of the CNS immune system?
Microglia
Perivascular macrophages
Astrocytes
Neutrophils under normal conditions
Explanation - Neutrophils are typically absent in the healthy CNS and only infiltrate during inflammation or injury.
Correct answer is: Neutrophils under normal conditions
Q.16 Meningeal lymphatic vessels are responsible for:
Transporting CSF to the venous system
Allowing immune cell trafficking from CNS to lymph nodes
Producing myelin
Stimulating neurons
Explanation - Meningeal lymphatics provide a route for CNS-derived immune cells and antigens to reach peripheral lymph nodes.
Correct answer is: Allowing immune cell trafficking from CNS to lymph nodes
Q.17 In neuroimmunology, the term 'immune privilege' refers to:
Complete absence of immune cells in CNS
Restricted immune responses to prevent damage
Enhanced immune activity
Rapid recruitment of neutrophils
Explanation - Immune privilege in the CNS allows limited immune responses to protect sensitive neural tissue from collateral damage.
Correct answer is: Restricted immune responses to prevent damage
Q.18 Which molecule is a pro-inflammatory mediator released by activated microglia?
IL-1β
Glutamate
GABA
Dopamine
Explanation - Activated microglia release IL-1β, a key cytokine that promotes inflammation and can affect neuronal function.
Correct answer is: IL-1β
Q.19 Which neuroimmune disorder is characterized by demyelination in the CNS?
Multiple sclerosis
Alzheimer's disease
Parkinson's disease
Epilepsy
Explanation - Multiple sclerosis involves autoimmune attack on CNS myelin, leading to neurological dysfunction.
Correct answer is: Multiple sclerosis
Q.20 Which CNS cells act as antigen-presenting cells under inflammatory conditions?
Microglia
Astrocytes
Oligodendrocytes
Neurons
Explanation - Microglia can present antigens to T cells when activated, bridging innate and adaptive immunity in the CNS.
Correct answer is: Microglia
Q.21 Neuroinflammation can contribute to which of the following in neurodegenerative diseases?
Neuronal death
Synaptic dysfunction
Cognitive decline
All of the above
Explanation - Chronic neuroinflammation is linked to neuronal death, synaptic dysfunction, and cognitive decline in neurodegenerative conditions.
Correct answer is: All of the above
Q.22 Which of the following molecules helps regulate T cell entry into the CNS?
VCAM-1
Acetylcholine
Dopamine
Glutamate
Explanation - VCAM-1 is expressed on CNS endothelial cells and facilitates adhesion and migration of T cells across the BBB.
Correct answer is: VCAM-1
Q.23 Which CNS structure is primarily responsible for filtering CSF and immune surveillance?
Choroid plexus
Cerebellum
Hippocampus
Pons
Explanation - The choroid plexus produces CSF and serves as a key site for immune cell trafficking and CNS immune surveillance.
Correct answer is: Choroid plexus
Q.24 Which of the following is a major mechanism by which peripheral inflammation affects CNS function?
Activation of vagus nerve signaling
Direct myelin production
Synapse formation
Neuron regeneration
Explanation - Peripheral inflammation can activate the vagus nerve and systemic cytokines, which communicate inflammatory signals to the CNS.
Correct answer is: Activation of vagus nerve signaling
Q.25 Which type of glial cell forms the first line of defense in CNS infections?
Microglia
Astrocytes
Oligodendrocytes
Ependymal cells
Explanation - Microglia act as the resident immune cells in the CNS and respond rapidly to infections or injury.
Correct answer is: Microglia