Podcast
Questions and Answers
What role does body temperature play in innate immunity?
What role does body temperature play in innate immunity?
- It alters the pH of cellular environments.
- It can inhibit the growth of certain pathogens. (correct)
- It enhances the activity of T-cells.
- It directly stimulates the production of antibodies.
How does gastric acidity function as a barrier to infection?
How does gastric acidity function as a barrier to infection?
- It induces fever to fight pathogens.
- It enhances nutrient absorption in the intestines.
- It kills most ingested microorganisms due to low pH. (correct)
- It activates antimicrobial proteins in the gut.
What is the primary function of collectins in the immune response?
What is the primary function of collectins in the immune response?
- To phagocytose and digest microorganisms
- To enhance the signaling of immune cells
- To disrupt the cell wall of pathogens (correct)
- To produce secretory proteins
What are pathogen-associated molecular patterns (PAMPs)?
What are pathogen-associated molecular patterns (PAMPs)?
What role do antimicrobial proteins and peptides play in innate immunity?
What role do antimicrobial proteins and peptides play in innate immunity?
What type of receptors are essential for detecting pathogens in the innate immune system?
What type of receptors are essential for detecting pathogens in the innate immune system?
Why are newborns more susceptible to certain infections compared to adults?
Why are newborns more susceptible to certain infections compared to adults?
What is the role of phagocytic cells in the immune response?
What is the role of phagocytic cells in the immune response?
How do epithelial barriers contribute to innate immunity?
How do epithelial barriers contribute to innate immunity?
What is the primary role of NOD1 and NOD2 in the immune system?
What is the primary role of NOD1 and NOD2 in the immune system?
What components are included in the external anatomical barriers of innate immunity?
What components are included in the external anatomical barriers of innate immunity?
Which statement accurately describes the NOD-like receptors (NLRs)?
Which statement accurately describes the NOD-like receptors (NLRs)?
What is the primary function of keratin in the epidermis?
What is the primary function of keratin in the epidermis?
What is the significance of damage-associated molecular patterns (DAMPs)?
What is the significance of damage-associated molecular patterns (DAMPs)?
What consequence can result from certain NLRs triggering inflammation?
What consequence can result from certain NLRs triggering inflammation?
What are the specialized cells involved in the process of phagocytosis?
What are the specialized cells involved in the process of phagocytosis?
What happens when there are breaks in the physical barriers of the body?
What happens when there are breaks in the physical barriers of the body?
What key feature distinguishes the epidermis from the dermis?
What key feature distinguishes the epidermis from the dermis?
Which of the following illustrates a cardinal sign of inflammation?
Which of the following illustrates a cardinal sign of inflammation?
What is primarily secreted by the body’s epithelial surfaces to combat pathogens?
What is primarily secreted by the body’s epithelial surfaces to combat pathogens?
What is the approximate number of NLR genes present in the human genome?
What is the approximate number of NLR genes present in the human genome?
How do molecular components of microbes, such as LPS, elicit an immune response?
How do molecular components of microbes, such as LPS, elicit an immune response?
According to Celsus, what are the 'four cardinal signs' of inflammation?
According to Celsus, what are the 'four cardinal signs' of inflammation?
What complex series of events is triggered by tissue damage caused by a wound or pathogen?
What complex series of events is triggered by tissue damage caused by a wound or pathogen?
What physiological change results in tissue redness and increased temperature during the inflammatory response?
What physiological change results in tissue redness and increased temperature during the inflammatory response?
What is the primary purpose of increased capillary permeability during inflammation?
What is the primary purpose of increased capillary permeability during inflammation?
Which process describes the movement of phagocytes through the tissue toward the site of invasion?
Which process describes the movement of phagocytes through the tissue toward the site of invasion?
What role do acute-phase proteins play in the inflammatory response?
What role do acute-phase proteins play in the inflammatory response?
Which cells are primarily responsible for the adherence and subsequent emigration during the inflammatory cascade?
Which cells are primarily responsible for the adherence and subsequent emigration during the inflammatory cascade?
How are chemical mediators involved in the inflammatory response?
How are chemical mediators involved in the inflammatory response?
Which of the following best describes margination in the context of the inflammatory response?
Which of the following best describes margination in the context of the inflammatory response?
Which acute-phase protein is notably produced by the liver in response to tissue damage?
Which acute-phase protein is notably produced by the liver in response to tissue damage?
What role does C-reactive protein play in the immune response?
What role does C-reactive protein play in the immune response?
What is the primary action of histamine in response to tissue injury?
What is the primary action of histamine in response to tissue injury?
How do kinins contribute to the inflammatory response?
How do kinins contribute to the inflammatory response?
Which of the following best describes the function of fibrin in the inflammatory response?
Which of the following best describes the function of fibrin in the inflammatory response?
What is the main characteristic of phagocytosis compared to other forms of endocytosis?
What is the main characteristic of phagocytosis compared to other forms of endocytosis?
What initiates the tissue repair process after the inflammatory response?
What initiates the tissue repair process after the inflammatory response?
Which type of endocytosis is primarily responsible for fluid uptake?
Which type of endocytosis is primarily responsible for fluid uptake?
What is the protective function of pain during the inflammatory response?
What is the protective function of pain during the inflammatory response?
Flashcards are hidden until you start studying
Study Notes
Innate Immunity Overview
- The body's first line of defense against pathogens.
- Consists of barriers that prevent pathogen entry and mechanisms that combat pathogens that breach these barriers.
Anatomical Barriers
- The most obvious component of innate immunity.
- Comprised of epithelial layers of skin and tissues.
- Includes mucous epithelial layers lining the respiratory, gastrointestinal, and urogenital tracts
- Epithelial barriers prevent pathogen entry into the body's interior.
- These barriers function as a "living plastic wrap" that protects the body from infection.
Epithelial Barriers
- Skin: Constitutes the outermost physical barrier, with two layers: epidermis and dermis.
- Epidermis: Contains tightly packed epithelial cells; its outer layer consists of dead cells filled with keratin.
- Keratin is a waterproofing protein that helps maintain skin integrity.
Physiological Barriers
- Include temperature, pH, and various soluble and cell-associated molecules.
- Normal body temperature inhibits the growth of certain pathogens.
- Gastric acidity is a barrier to infection as many ingested microorganisms cannot survive the low pH of the stomach.
- Newborns are susceptible to diseases that adults are not due to less acidic stomach contents.
Antimicrobial Proteins and Peptides
- Epithelial cells secrete a broad spectrum of antimicrobial proteins and peptides to combat pathogens.
- These molecules contribute to the defense of barrier layers against pathogens.
- The continuous production of antimicrobial agents helps control microbial populations on these surfaces.
Cellular Innate Response Receptors and Signaling
- Pattern recognition receptors (PRRs) play crucial roles in detecting pathogens and activating innate immune responses.
- PRRs bind to pathogen-associated molecular patterns (PAMPs) that trigger cellular responses.
- Some PRRs reside on the plasma membrane, recognizing extracellular pathogens, while others are found inside cells, detecting endocytosed pathogens or cytoplasmic bacteria and viral nucleic acids.
- PRRs ensure the recognition of PAMPs from virtually any pathogen, both extracellular and intracellular.
Nod-Like Receptors (NLRs)
- A large family of cytosolic proteins crucial in innate immunity.
- Activated by intracellular PAMPs and DAMPs (damage-associated molecular patterns).
- Contribute to activating beneficial innate immune and inflammatory responses.
NLR Function
- NLRs trigger autophagy, a process where the endoplasmic reticulum engulfs bacteria to form autophagosomes.
- Autophagosomes fuse with lysosomes, leading to the destruction of bacteria.
Inflammation: A Complex Sequence of Events
- Tissue damage from wounds or pathogens initiates the inflammatory response.
- LPS (lipopolysaccharide), a microbial component, can trigger inflammation through interaction with cell surface receptors.
- The goal of inflammation is to orchestrate a specific immune response or eliminate the invader using innate immune system components.
Cardinal Signs of Inflammation
- Rubor (Redness): Engorged capillaries due to vasodilation.
- Tumor (Swelling): Fluid accumulation (exudate) in the tissue causes edema.
- Calor (Heat): Increased tissue temperature due to engorged capillaries.
- Dolor (Pain): Stimulation of pain receptors in the skin.
- Functio Laesa (Loss of Function): Impairment of tissue function.
Major Events of Inflammation
- Vasodilation: Increase in blood vessel diameter to enhance blood flow to the site of inflammation.
- Increased Capillary Permeability: Allows fluid and cells to leak from blood vessels into the tissue.
- Influx of Phagocytes: Movement of phagocytic cells from the blood into the tissue to ingest pathogens.
Mediators of Inflammation
- A complex interplay of chemical mediators initiates the inflammatory response.
- These mediators include molecules from invading microorganisms, damaged cells, plasma enzyme systems, and white blood cells.
Acute-Phase Proteins
- Serum proteins that increase dramatically in tissue-damaging infections.
- C-reactive protein (CRP) is a major acute-phase protein produced by the liver.
- CRP binds to bacterial and fungal cell wall components, activating the complement system.
Histamine: Key Inflammatory Mediator
- Released by various cells in response to tissue injury.
- Causes vasodilation and increased permeability by binding to receptors on capillaries and venules.
Kinins: Important Inflammatory Mediators
- Small peptides normally present in inactive form in blood plasma.
- Activated by tissue injury, causing vasodilation, increased permeability, and pain stimulation (bradykinin).
Blood-Clotting System
- Enzymes from the blood-clotting system enter injured tissue, activating an enzyme cascade that forms fibrin strands.
- Fibrin strands wall off the injured area, preventing infection spread.
Tissue Repair and Regeneration
- Following inflammation resolution, tissue repair and regeneration begin.
Phagocytosis
- A type of endocytosis, where cells engulf particulate matter, including pathogens, to form phagosomes.
- Primarily performed by specialized cells like monocytes, neutrophils, and macrophages.
- Other forms of endocytosis include receptor-mediated endocytosis and pinocytosis.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
