p.1
Acute vs Chronic Inflammation
What characterizes acute inflammation?
Predominantly alterations in blood vessels to increase blood flow and edema, and the action of neutrophils.
p.4
Vascular Changes in Inflammation
What is a typical cause of hepatic congestion?
Increased central venous pressure in congestive heart failure.
p.4
Vascular Changes in Inflammation
What morphological change occurs in activated endothelial cells?
They take on a more cuboidal shape.
p.11
B and T Cell Functions in Immune Response
What is the role of CD4+ T cells and APCs in B cell activation?
They select for the formation of cells expressing immunoglobulin that can functionally bind antigen.
p.3
Vascular Changes in Inflammation
How does congestion differ from hyperemia?
Congestion is a passive process due to decreased venous return, while hyperemia is an active physiological reaction.
p.8
Types of Inflammatory Cells
What shape are macrophage nuclei typically?
Single, oval to kidney bean-shaped.
p.2
Cytokines and Inflammatory Mediators
What is the role of substance P, bradykinin, and prostaglandins in acute inflammation?
They contribute to pain (dolor) through neural stimulation and tissue effects.
p.10
B and T Cell Functions in Immune Response
What do CD8+ T cells recognize?
Virally infected cells in the context of class I MHC antigens.
p.5
Vascular Changes in Inflammation
What happens after inflammatory cells adhere to endothelial cells?
They undergo further activation and actively transmigrate between endothelial junctions into the interstitium.
p.4
Vascular Changes in Inflammation
What accumulates in the alveoli due to chronic congestion in the lungs?
Hemosiderin-containing macrophages.
p.11
B and T Cell Functions in Immune Response
Where do B cells derive from?
Common lymphoid progenitor cells in the bone marrow.
p.9
Overview of Inflammation
What is the primary function of platelets at sites of vascular damage?
To act as initial hemostatic effectors.
p.11
B and T Cell Functions in Immune Response
What type of antibodies do mature B cells primarily produce?
IgG, which accounts for 85% of the immunoglobulin in normal serum.
p.2
Vascular Changes in Inflammation
What are the earliest changes in acute inflammation?
Vascular changes rather than inflammatory cell infiltration.
p.8
Mechanisms of Innate and Adaptive Immunity
How do macrophages contribute to adaptive immunity?
They act as antigen-presenting cells (APCs) and coordinate interactions between T and B cells.
p.6
Role of Neutrophils in Inflammation
What is the function of myeloperoxidase and lysozyme in neutrophils?
They are directly involved in the killing of microorganisms.
p.7
Role of Neutrophils in Inflammation
What are the three steps in neutrophil-mediated killing of microorganisms?
1) Recognition, 2) Binding, 3) Engulfment.
p.7
Types of Inflammatory Cells
What triggers the degranulation of mast cells?
Antigen binding to IgE or other stimuli like heat, cold, or mechanical stimulation.
p.5
Mechanisms of Innate and Adaptive Immunity
What are chemotactic factors and their function?
Chemotactic factors direct the migration of inflammatory cells through the interstitial space to the site of inflammation.
p.1
Mechanisms of Innate and Adaptive Immunity
What can accelerate the acute inflammatory reaction?
The presence of specific antibodies for a particular pathogen.
p.11
B and T Cell Functions in Immune Response
What is the primary function of B lymphocytes?
To produce specific immunoglobulin molecules of high affinity that can react with exogenous antigens.
p.9
Vascular Changes in Inflammation
What triggers the platelet release reaction?
Platelet binding to surfaces and activated endothelial cells.
p.10
B and T Cell Functions in Immune Response
What is the role of CD4+ helper T cells?
They interact with B cells and promote B cell maturation.
p.2
Abscess Formation and Consequences
What is an abscess?
A collection of neutrophils, macrophages, and necrotic debris that has undergone liquefaction.
p.5
Vascular Changes in Inflammation
What role do integrins and selectins play in inflammation?
They promote the binding of inflammatory cells to the endothelial surface and trigger their initial activation.
p.1
Types of Inflammatory Cells
Which cells are predominantly involved in acute inflammatory reactions?
Neutrophils, often in association with eosinophils.
p.9
Overview of Inflammation
What are platelets derived from?
Megakaryocytes in the bone marrow.
p.8
Types of Inflammatory Cells
What are macrophages derived from?
Myelomonocytic precursors in the bone marrow.
p.8
Types of Inflammatory Cells
What can convert macrophages into activated histiocytes?
Secretion of interferon γ (IFN-γ) by T H 1 T cells.
p.10
Cytokines and Inflammatory Mediators
What is the function of IL-5 produced by T H 2 cells?
It activates eosinophils.
p.2
Cytokines and Inflammatory Mediators
What systemic manifestations can activated macrophages produce in an abscess?
Cytokines resulting in fever and other systemic symptoms.
p.7
Types of Inflammatory Cells
What is the consequence of excessive mast cell activation?
Systemic edema and vasodilation, leading to anaphylactic shock.
p.4
Vascular Changes in Inflammation
What does congestion predispose to in tissues?
Hemorrhage (bleeding) into tissue.
p.1
Acute vs Chronic Inflammation
What happens to acute inflammation after 48 to 72 hours?
It transitions to a mixed acute and chronic inflammatory cell infiltrate.
p.3
Acute vs Chronic Inflammation
What cells are primarily recruited during the transition from acute to chronic inflammation?
Longer-lived mononuclear cells, such as macrophages and lymphocytes.
p.3
Acute vs Chronic Inflammation
What type of cells are typically present in chronic inflammation?
Lymphocytes, macrophages, and plasma cells.
p.11
B and T Cell Functions in Immune Response
What is the significance of the IgG constant region?
It permits effective binding to Fc receptors on inflammatory cells, enhancing phagocytosis of microorganisms.
p.2
Cytokines and Inflammatory Mediators
What do endothelial cells release in response to injury?
Various inflammatory mediators that cause vasodilation and increased vascular permeability.
p.2
Abscess Formation and Consequences
What may happen if viable microorganisms remain in an abscess?
The acute inflammatory response usually intensifies and may result in abscess formation.
p.1
Overview of Inflammation
What is the primary role of inflammation in the body?
It serves as a host defense against microorganisms and parasites, and is the first response to injuries.
p.4
Vascular Changes in Inflammation
What happens to hepatocytes during increased central venous pressure?
They are put under pressure, disrupting their normal function and potentially causing cell death.
p.4
Vascular Changes in Inflammation
What promotes the contraction of vascular endothelial cells during inflammation?
Acute inflammatory mediators.
p.3
Chronic Inflammation and Tissue Repair
What are granulomas and what do they indicate?
Concentric nodules formed by histiocytes, often helpful in identifying the cause of inflammation.
p.11
B and T Cell Functions in Immune Response
What type of antibodies are predominantly produced by mucosa-associated B cells?
IgA, which provides a barrier to some pathogens in the gastrointestinal tract.
p.6
Types of Inflammatory Cells
What are the main types of inflammatory cells?
Neutrophils, basophils, eosinophils, lymphocytes, monocytes, macrophages, and plasma cells.
p.10
Cytokines and Inflammatory Mediators
What initiates cytokine synthesis in T cells?
Signal transduction mediated through the T-cell receptor complex (TCR).
p.8
Mechanisms of Innate and Adaptive Immunity
What is the significance of class II MHC molecules in macrophages?
They are necessary for antigen presentation to activate T cells.
p.6
Types of Inflammatory Cells
What do tertiary granules in neutrophils contain?
Proteases and gelatinase, important for degrading basement membrane components.
p.7
Role of Neutrophils in Inflammation
What does MPO convert hydrogen peroxide to in neutrophils?
Hypochlorite and superoxide free radicals.
p.5
Vascular Changes in Inflammation
What is PECAM and its role in inflammation?
PECAM (CD31) is a transmembrane protein that allows transmigration of inflammatory cells between endothelial cells into the interstitium.
p.5
Overview of Inflammation
How does acute inflammation affect blood flow?
It promotes blood flow to the injured area, increasing the potential number of inflammatory cells available.
p.4
Vascular Changes in Inflammation
What can long-standing hepatic congestion lead to?
Fibrosis and organ dysfunction.
p.3
Chronic Inflammation and Tissue Repair
What is granulomatous inflammation characterized by?
The presence of an inflammatory node containing compactly grouped mononuclear phagocytes.
p.6
Mechanisms of Innate and Adaptive Immunity
What are the two types of immunity discussed in relation to inflammatory cells?
Innate immunity and adaptive immunity.
p.6
Mechanisms of Innate and Adaptive Immunity
What is phagocytosis?
The process by which inflammatory cells ingest microorganisms.
p.2
Vascular Changes in Inflammation
What leads to swelling (tumor) or edema in acute inflammation?
Increased vascular permeability and actions of inflammatory mediators.
p.7
Types of Inflammatory Cells
What role do eosinophils play in the inflammatory response?
They are important in responding to parasites and allergic reactions.
p.5
Abscess Formation and Consequences
What can happen if inflammatory stimuli continue?
Accumulation may progress to abscess formation due to excess neutrophils.
p.9
Mechanisms of Innate and Adaptive Immunity
What is the role of immunosurveillance in tumors?
To detect tumors that may evade T cells by ceasing MHC expression.
p.11
B and T Cell Functions in Immune Response
What is required for B cells to undergo initial antigen stimulation?
Migration to lymph nodes or extranodal lymphoid organs.
p.3
Vascular Changes in Inflammation
What vascular changes occur during acute inflammation?
Hyperemia, congestion, edema, and endothelial cell activation.
p.6
Mechanisms of Innate and Adaptive Immunity
What initial role does innate immunity play in response to infections?
It provides the initial response to most insults and contains pathogens until adaptive immunity can respond.
p.10
B and T Cell Functions in Immune Response
What distinguishes CD8+ T cells?
They are prototypical cytotoxic T cells that induce apoptotic cell death.
p.2
Role of Neutrophils in Inflammation
What initiates the recruitment of neutrophils to sites of inflammation?
Release of inflammatory mediators from injured endothelial cells.
p.10
B and T Cell Functions in Immune Response
What role do CD8+ T cells play in transplants?
They mediate transplant rejection in response to foreign histocompatibility antigens.
p.5
Vascular Changes in Inflammation
How do inflammatory cells gain access to the interstitium?
By releasing proteases that digest basement membrane material.
p.12
Chronic Inflammation and Tissue Repair
How does inflammation relate to tissue repair?
Inflammation is essential for initiating the tissue repair process.
p.9
Cytokines and Inflammatory Mediators
What important mediators do platelets synthesize?
Arachidonic acid-derived mediators, especially thromboxane.
p.4
Vascular Changes in Inflammation
What proteins are redistributed to the luminal surface of endothelial cells during activation?
Selectin and integrin proteins.
p.11
B and T Cell Functions in Immune Response
What triggers hypermutation in B cells?
Secondary lymphoid follicles.
p.6
Mechanisms of Innate and Adaptive Immunity
How does adaptive immunity differ from innate immunity?
Adaptive immunity depends on specific antigen-recognition molecules.
p.8
Cytokines and Inflammatory Mediators
What do macrophages secrete that is crucial for inflammation?
Cytokines, including IL-1 and TNF-α.
p.6
Types of Inflammatory Cells
What do primary granules in neutrophils contain?
Acid hydrolases, elastase, serine proteases, myeloperoxidase, and lysozyme.
p.8
Mechanisms of Innate and Adaptive Immunity
What is the role of NK cells in viral infections?
They provide an early response before antigen-specific T cells are activated.
p.1
Acute vs Chronic Inflammation
What are the two main types of inflammation?
Acute and chronic inflammation.
p.12
Mechanisms of Innate and Adaptive Immunity
What mechanisms are explored in this section?
Cellular and molecular mechanisms of disease.
p.1
Acute vs Chronic Inflammation
What can prolong acute inflammation?
The persistence of viable bacteria in pyogenic bacterial infections.
p.3
Mechanisms of Innate and Adaptive Immunity
What is the function of TH1 T cells in granulomatous inflammation?
They secrete IFN-γ and other cytokines that convert macrophages to epithelioid histiocytes.
p.11
B and T Cell Functions in Immune Response
What does the presence of serum IgG in the absence of IgM indicate?
Evidence of prior infection.
p.6
Role of Neutrophils in Inflammation
What is the primary role of neutrophils?
They are the most important agents of response to pyogenic bacterial infections and initial responders to physical injury.
p.2
Overview of Inflammation
What are the classical localized manifestations of acute inflammation?
Rubor, calor, tumor, and dolor.
p.8
Types of Inflammatory Cells
What surface markers do NK cells express?
They are CD56-positive and express Fc receptors but do not express T-cell antigen receptors, CD8, or CD4.
p.2
Abscess Formation and Consequences
What can occur if an abscess spreads to a body cavity?
It can cause generalized inflammation and infection, leading to empyema or peritonitis.
p.7
Cytokines and Inflammatory Mediators
What additional mediators are produced upon mast cell activation?
Prostaglandins and leukotrienes.
p.4
Vascular Changes in Inflammation
What is edema in the context of acute inflammation?
Fluid accumulation in tissues due to disrupted hydrostatic pressure.
p.3
Chronic Inflammation and Tissue Repair
What role do macrophages play in chronic inflammation?
They engulf cellular debris to facilitate tissue repair.
p.9
Mechanisms of Innate and Adaptive Immunity
What is required for adaptive immunity to occur?
The generation of antigen-specific receptor molecules.
p.3
Vascular Changes in Inflammation
What is hyperemia?
An active process where blood volume and flow are increased due to dilation of arterioles.
p.8
Acute vs Chronic Inflammation
What is the primary role of macrophages in chronic inflammation?
They are major effector cells involved in phagocytizing microorganisms and coordinating inflammatory processes.
p.8
Chronic Inflammation and Tissue Repair
What is the role of macrophages in tissue repair?
They clear debris and damaged material to facilitate healing.
p.10
Cytokines and Inflammatory Mediators
What is the role of IFN-γ produced by T H 1 cells?
It activates macrophages and can convert them to epithelioid histiocytes.
p.5
Acute vs Chronic Inflammation
What is an inflammatory exudate?
Fluid oozing out of a tissue or its capillaries due to injury or inflammation.
p.3
Acute vs Chronic Inflammation
What is the lifespan of neutrophils during an acute inflammatory response?
48 hours in circulation, usually much less in inflamed tissues.
p.9
B and T Cell Functions in Immune Response
Where do progenitor T cells migrate to become mature T cells?
The cortex of the thymus.
p.6
Mechanisms of Innate and Adaptive Immunity
What characterizes innate immunity?
It comprises cellular and humoral processes that respond independently of antigen-specific recognition molecules.
p.10
Cytokines and Inflammatory Mediators
How are helper T cells further categorized?
As T H 1 or T H 2 based on the types of cytokines they secrete.
p.8
Types of Inflammatory Cells
What type of cells are natural killer (NK) cells?
Lymphocytes of intermediate size that are an important component of innate immunity.
p.7
Role of Neutrophils in Inflammation
What happens after neutrophils engulf microorganisms?
Primary granules fuse with the phagosome.
p.7
Types of Inflammatory Cells
How do eosinophils attack larger parasites?
By degranulating and releasing granule contents into the extracellular space.
p.5
Chronic Inflammation and Tissue Repair
What factors can cause severe tissue damage during inflammation?
Hydrolytic enzymes, inflammatory mediators, and oxygen-derived free radicals released from neutrophils.
p.5
Acute vs Chronic Inflammation
What limits the time frame of an inflammatory response?
The short tissue life span of neutrophils, usually measured in hours.
