Lesson 1-5 Flashcards
pathogens of low virulence that will only cause disease if administered in very high doses
Opportunistic pathogen
a pathogen which cause disease almost every time it invades a healthy individual even in low numbers
primary pathogen
capacity of immune system to remember an antigen and react more vigorously upon re-exposure of the same antigen
Immunological memory
failure of immune system to develop tolerance for self-proteins and starting immune response
Autoimmunity
refers to an antigen induced specific unresponsiveness
tolerance
the means of providing specific protection against a damaging pathogen
Immunization
proteins used for intercellular communication and intracellular signaling pathways
Chemokines
part of antibody which recognizes the antigen
Paratope
protein (globulin) which is reactive against specific antigen
antibody
Part of Antigen recognized by immune system
epitope
Small portion of antigen which by it self can not elicit immune reaction
hapten
A molecule that stimulates immune response (generally proteins
antigen
Give the four functions of the immune response
- Immunological recognition
- Immune effector functions
- Immune regulation
- Immunological memory
the resistance that an individual possesses by birth
Innate immunity
large phagocytic tissue cells, responsible for removal of damaged tissue, cells, bacteria
Macrophages
short-lived scavenger blood cells containing granules of powerful bactericidal enzymes
neutrophils
present antigen to T cells to initiate adaptive immune responses
dendritic cells
lymphocyte-like cells capable of killing virus infected and tumor cells without the specificity of true lymphocytes
Natural killer cells
found in tissues, release inflammatory mediators when damaged and under the influence of IgE antibody
Mast cells
Give the mediators of inflammatory reactions (4)
- Histamine
- Kinins
- Acute phase proteins
- Defensins
causes vasodilation and increased capillary permeability during inflammatory reaction
Kinins
Optimize and traps microorganism and their products, activates the complement system
Acute phase proteins
peptides that produce pores in membrane of the bacteria and thereby kill them
Defensins
Immunity with potency of immune response is acquired by experience only
Adaptive immunity
resistance to infection that an individual possesses by virtue of genetic and constitutional makeup
Innate Immunity
Type of adaptive immunity induced by exposure to a foreign antigen
Active immunity
An immunity acquired by natural clinical or sub-clinical infections that eventually results to long-lasting immunity
Natural active
Active immunity induced by vaccines
Artificial active
immunity is conferred by transfer of serum or lymphocytes from a specifically immunized individual
Passive immunity
Type of immunity whereby the maternal transfer of antibodies from mother to fetus during pregnancy and breastfeeding occur.
Natural passive
Immunity induced in an individual by
administration of preformed antibodies, generally in the form of antiserum
Artificial passive
Infectious disease which uses combined passive-active immunity as prevention
tetanus, rabies, and hepatitis
B
carried out by giving both preformed antibodies (antiserum) and a vaccine to provide immediate protection and long-term protection, respectively, against a disease
Combined passive-active immunity
Enumerate the four families of PRRs
- Toll-like receptors (TLR)
- Nucleotide-binding oligomerization domain-like receptors (NLR)
- C-type lectin receptors (CLR)
- RIG-1 like receptors (RLR)
Differences of the four families of PRRs
- Ligand recognition
- Signal transduction
- Sub-cellular localization
This PRR are localized at the plasma membrane recognizing glycans from the wall of fungi and some bacteria
C-type lectin receptors
These are cytoplasmic sensors which form multiprotein signalling complexes known as inflammasomes & activate caspase-1-mediated
Nucleotide-binding oligomerization domain-like receptors
Transmembrane proteins localized either at the plasma membrane or in endosomes that activates MAP kinase, Nuclear factor kappa B
Toll-like receptors
These are cytoplasmic sensors of viral RNA that signals via the mitochondrial adaptor protein MAVS
RIG-1 like receptors
Which of the TLRs recognize viral double-stranded RNA?
TLR3
Which of the TLRs recognize flagellin and flagellated bacteria?
TLR5
Which of the TLRs recognize small antiviral molecules?
TLR7, TLR8
Which of the TLRs recognize a pseudogene?
TLR10
Which of the TLRs recognize diacetylated lipoproteins?
TLR1
Give some natural ligands in microbes or damaged tissues recognized by TLR4:
- LPS
- lipotechoieic acid
- viral protein
- heat-shock protein
- fibrinogen
- saturated fatty acids
- B-defensins
- heparan sulfate
Which of the TLRs recognize unmethylated CpG bacterial DNA
TLR9
Which of the TLRs recognize lipoproteins, peptidoglycan, spirochetes, mycobacteria?
TLR2
These are molecules released when cells die (intracellular) or generated when connective tissue is damaged
DAMPs or Alarmins
Cell death initiated in response to infections and other irritants that generate inflammasomes
Pyroptosis
Enumerate the properties of cytokines
- Short-lived proteins
- Highly diverse structures and receptors
- Can act locally and/or systemically
- Pleiotropic: affect many different cells
- Redundant: exhibit biologically overlapping functions
- Carefully regulated
- Toxic in high doses
Give the four common cytokines
- Interleukins
- Interferons
- Tumor necrosis factors
- Chemokines
Which cytokines signal between lymphocytes and other leukocytes?
Interleukins
These cytokines are produced in response to virus infection or immune stimulation:
Interferons
These are cytokines produced by macrophages and T cells involved in the coordination of host defenses, cell survival, immune regulation and inflammation:
Tumor necrosis factor
A family of at least 50 small proteins that play a role in leukocyte chemotaxis, circulation, migration, and activation, especially in inflammation
Chemokines
Give the 3 effects on how cytokines act on many targets
- Autocrine effect
- Paracrine effect
- Endocrine effect
Enumerate the 3 ways of cytokine regulation:
- by changes in receptor expression
- by the presence of specific binding proteins
- by cytokines that exert opposing effect
Which of the following BEST describes a hapten?
a) A large molecule that stimulates an immune response.
b) A protein secreted by immune cells for communication.
c) A small molecule that can elicit an immune response on its own.
d) A small molecule that can only elicit an immune response when attached to a carrier protein.
A small molecule that can only elicit an immune response when attached to a carrier protein.
The part of an antibody that recognizes and binds to an antigen is called:
Paratope
Which of the following is NOT a characteristic of innate immunity?
a) Rapid response
b) Specificity
c) Immunological memory
d) Activation of adaptive immunity
Immunological memory
Which cell type is primarily responsible for presenting antigens to T cells?
a) Neutrophils
b) Macrophages
c) Dendritic cells
d) Natural Killer cells
Dendritic cells
Which of the following is an example of natural passive immunity?
a) Vaccination
b) Transfer of antibodies through breast milk
c) Exposure to a pathogen
d) Injection of antiserum
Transfer of antibodies through breast milk
Autoimmunity occurs when the immune system fails to:
a) Recognize foreign antigens
b) Develop tolerance to self-antigens
c) Generate immunological memory
d) Activate complement
Develop tolerance to self-antigens
Which of the following is NOT a function of the immune system?
a) Immunological recognition
b) Containment and elimination of infection
c) Unlimited immune response
d) Immunological memory
Unlimited immune response
Which type of immunity is induced by a vaccine?
Artificial active
Which of the following is a primary pathogen?
a) A pathogen that causes disease only when present in high numbers.
b) A pathogen that causes disease almost every time it invades a healthy individual.
c) A pathogen that requires a compromised immune system to cause disease.
d) A pathogen that causes disease only in specific age groups.
A pathogen that causes disease almost every time it invades a healthy individual.
Which of the following is an example of species immunity?
a) Humans being susceptible to tuberculosis while chickens are resistant.
b) Individuals with a glucose-6-phosphate dehydrogenase deficiency being less susceptible to malaria.
c) One identical twin developing tuberculosis, and the other twin also developing it.
d) Different breeds of dogs having varying susceptibilities to certain diseases.
Humans being susceptible to tuberculosis while chickens are resistant.
Which of the following is NOT a soluble component of innate immunity?
a) Complement
b) Cytokines
c) Defensins
d) Macrophages
Macrophages
Which of the following is NOT a mechanism of innate immunity?
a) Anatomic barriers
b) Antibody production
c) Phagocytosis
d) Inflammatory response
Antibody production
Which of the following is NOT a mediator of inflammatory reactions?
a) Histamine
b) Kinins
c) Antibodies
d) Acute-phase proteins
Antibodies
Which factor does NOT influence innate immunity?
a) Age
b) Nutritional status
c) Genetic makeup
d) Prior exposure to an antigen
Prior exposure to an antigen
Which type of immunity is mediated by B cells?
a) Cell-mediated immunity
b) Humoral immunity
c) Innate immunity
d) Passive immunity
Humoral immunity
Which type of T cells are involved in killing virus-infected cells?
a) Helper T cells
b) Cytotoxic T cells
c) Regulatory T cells
d) Memory T cells
Cytotoxic T cells
Local immunity is primarily mediated by:
a) IgG antibodies
b) IgA antibodies
c) IgM antibodies
d) IgE antibodies
IgA antibodies
Herd immunity refers to:
The overall level of immunity in a community.
Which of the following is an example of artificial passive immunity?
a) Passing of antibodies through the placenta.
b) Receiving a vaccine.
c) Injection of antibodies in the form of antiserum.
d) Developing immunity after recovering from an infection.
Injection of antibodies in the form of antiserum.
Which of the following best describes immunological memory?
a) The ability of the immune system to respond immediately and effectively upon subsequent encounters with the same antigen.
b) The ability of the immune system to distinguish between self and non-self.
c) The ability of the immune system to mount an inflammatory response.
d) The ability of the immune system to produce antibodies.
The ability of the immune system to respond immediately and effectively upon subsequent encounters with the same antigen.
Which of the following BEST distinguishes between active and passive immunity?
a) The duration of protection.
b) The involvement of B cells.
c) Whether antibodies are involved.
d) Whether the individual produces their own antibodies.
Whether the individual produces their own antibodies.
Which of the following is NOT a characteristic of a good antigen?
a) High molecular weight
b) Chemical complexity
c) Degradability
d) Small, repetitive structures
Small, repetitive structures
Which cell type bridges innate and adaptive immunity?
a) Neutrophils
b) Macrophages
c) Dendritic cells
d) Natural Killer cells
Dendritic cells
Which interleukin is crucial for the differentiation of T helper cells into Th1 cells?
IL-12
Which of the following is an example of combined passive-active immunization?
a) Administering a vaccine.
b) Transferring maternal antibodies through the placenta.
c) Giving both antiserum and a vaccine simultaneously.
d) Receiving a blood transfusion.
Giving both antiserum and a vaccine simultaneously.
Which of the following is NOT a function of antibodies?
a) Neutralization of toxins
b) Opsonization
c) Direct killing of infected cells
d) Activation of complement
Direct killing of infected cells (Antibodies mark cells for destruction, but don’t kill them directly)
Which of the following statements about immunological tolerance is INCORRECT?
a) It is antigen-specific.
b) It involves the elimination or inactivation of self-reactive lymphocytes.
c) Failure of tolerance leads to autoimmunity.
d) It is a feature of innate immunity.
It is a feature of innate immunity.
Which of the following is a key characteristic of immunological memory?
a) A faster and stronger response upon re-exposure to an antigen.
b) The ability to recognize an unlimited number of antigens.
c) The ability to distinguish between self and non-self.
d) The ability to mount an inflammatory response.
A faster and stronger response upon re-exposure to an antigen.
Which of the following best describes the role of inflammation in immunity?
a) It is always harmful and should be suppressed.
b) It is a complex process involving various cell types and mediators, crucial for tissue repair and pathogen clearance.
c) It is solely mediated by mast cells and histamine release.
d) It is only triggered by infection.
It is a complex process involving various cell types and mediators, crucial for tissue repair and pathogen clearance.
Case: A 6-month-old Labrador Retriever puppy presents with recurrent episodes of pyoderma (skin infection). The puppy has received its core vaccinations. What is the MOST likely underlying cause, considering the puppy’s age and recurring infections?
a) Vaccine failure
b) Immunodeficiency
c) Allergic dermatitis
d) Parasitic infection
Immunodeficiency
A cat, Feline Leukemia Virus positive, presents with chronic gingivitis and stomatitis. What is the MOST likely explanation for the severity of these oral lesions in this cat?
a) The FeLV infection is causing immunosuppression.
b) The cat has a food allergy.
c) The cat has poor dental hygiene.
d) The cat is developing oral cancer.
The FeLV infection is causing immunosuppression.
A horse develops hives and facial swelling after being administered a new medication. What type of hypersensitivity reaction is MOST likely occurring?
Type I (Immediate hypersensitivity)
Case: A dog with a history of atopy (allergies) exhibits severe pruritus (itching) and skin lesions. Which cell type plays a CENTRAL role in mediating the allergic response in this condition?
Mast cells
Case: A dog is diagnosed with a tumor. Which component of the immune system is PRIMARILY responsible for recognizing and destroying cancerous cells?
Cytotoxic T lymphocytes (CTLs)
A cat presents with a non-healing wound. Biopsy reveals a large number of macrophages and neutrophils at the wound site. What process is occurring at the wound site?
a) Immunological tolerance
b) Inflammation
c) Autoimmunity
d) Apoptosis
Inflammation
Which of the following BEST describes pathogen-associated molecular patterns (PAMPs)?
a) Molecules released by damaged host cells.
b) Conserved molecular structures found in microbes.
c) Receptors on immune cells that recognize pathogens.
d) Proteins secreted by immune cells for communication.
Conserved molecular structures found in microbes.
Pattern recognition receptors (PRRs) are primarily expressed on:
a) Epithelial cells
b) Immune cells
c) All cell types
d) Pathogens
Immune cells
Which of the following is an example of a PAMP?
a) Lipopolysaccharide (LPS)
b) Interleukin-2 (IL-2)
c) Tumor Necrosis Factor (TNF)
d) Antibodies
Lipopolysaccharide (LPS)
Damage-associated molecular patterns (DAMPs) are released from:
a) Healthy cells
b) Damaged or dying cells
c) Invading pathogens
d) Immune cells
Damaged or dying cells
Which of the following is NOT a major family of PRRs?
a) Toll-like receptors (TLRs)
b) Nucleotide-binding oligomerization domain-like receptors (NLRs)
c) C-type lectin receptors (CTLRs)
d) Antibody receptors
Antibody receptors
Sentinel cells are primarily responsible for:
a) Producing antibodies
b) Recognizing and responding to pathogens
c) Killing infected cells
d) Presenting antigens to T cells
Recognizing and responding to pathogens
Which of the following are examples of sentinel cells?
a) Macrophages, dendritic cells, and mast cells
b) B cells and T cells
c) Neutrophils and eosinophils
d) Fibroblasts and epithelial cells
Macrophages, dendritic cells, and mast cells
Where are TLRs typically located?
a) Only on the cell surface
b) Only in the cytoplasm
c) On the cell surface and in endosomes
d) Only in the nucleus
On the cell surface and in endosomes
Which of the following best describes the role of PRRs in innate immunity?
a) They initiate the adaptive immune response.
b) They directly kill invading pathogens.
c) They recognize PAMPs and DAMPs, triggering cellular responses.
d) They produce antibodies.
They recognize PAMPs and DAMPs, triggering cellular responses
Which of the following is NOT a function of cytokines?
a) Cell-to-cell communication
b) Promoting inflammation
c) Directly recognizing and binding to pathogens
d) Regulating immune responses
Directly recognizing and binding to pathogens
Which of the following is a characteristic of cytokines?
a) They are long-lived proteins.
b) They have highly diverse structures and receptors.
c) They act only locally.
d) They are produced only by immune cells.
They have highly diverse structures and receptors.
Which of the following is an example of a cytokine?
a) Lipopolysaccharide (LPS)
b) Interleukin-1 (IL-1)
c) Toll-like receptor 4 (TLR4)
d) Complement protein C3
Interleukin-1 (IL-1)
What does the term “pleiotropic” mean in the context of cytokines?
a) They have redundant functions.
b) They act on many different cell types.
c) They are produced by many different cell types.
d) They act only on nearby cells.
They act on many different cell types.
What is the difference between apoptosis and pyroptosis?
a) Apoptosis triggers inflammation, while pyroptosis does not.
b) Pyroptosis triggers inflammation, while apoptosis does not.
c) Apoptosis and pyroptosis are the same process.
d) Apoptosis is cell death due to injury, pyroptosis is programmed cell death.
Pyroptosis triggers inflammation, while apoptosis does not.
Which cell death pathway is associated with the formation of inflammasomes?
a) Apoptosis
b) Pyroptosis
c) Necroptosis
d) All of the above
Pyroptosis
Which cell type is NOT typically considered a sentinel cell?
a) Macrophage
b) Dendritic cell
c) B lymphocyte
d) Mast cell
B lymphocyte
Which of the following is NOT a property of cytokines?
a) Short-lived proteins.
b) Can act locally and/or systemically.
c) Always beneficial to the host.
d) Pleiotropic effects.
Always beneficial to the host.
What is the primary function of chemokines?
a) Attract immune cells to the site of infection.
b) Kill infected cells directly.
c) Present antigens to T cells.
d) Produce antibodies.
Attract immune cells to the site of infection.
