Human Immunology Overview

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Questions and Answers

What is the primary function of red blood cells (RBCs)?

Transporting oxygen and removing carbon dioxide (correct)

Initiating the inflammatory response

Releasing growth factors for tissue repair

Transporting antibodies to fight infections

Which type of white blood cell (WBC) is the most abundant in the immune response?

Neutrophils (correct)

Basophils

Monocytes

Eosinophils

What characterizes acute inflammation?

It only occurs in response to chronic illnesses.

It is the body's immediate response to injury or infection. (correct)

It occurs over a prolonged period.

It leads to chronic tissue damage.

What role do platelets play in inflammation?

They release growth factors and cytokines. Signup and view all the answers

Which condition is an example of chronic inflammation?

Hepatitis B infection Signup and view all the answers

Which white blood cell type is primarily involved in allergic responses and combating parasitic infections?

Eosinophils Signup and view all the answers

What does the suffix '-itis' indicate in medical terminology?

Inflammation of a specific organ or tissue Signup and view all the answers

What is the role of monocytes in the immune response?

Differentiating into macrophages or dendritic cells Signup and view all the answers

What differentiates colonization from contamination?

Colonization is part of normal flora without causing disease. Signup and view all the answers

Which of the following best describes chronic inflammation?

A prolonged response leading to tissue damage. Signup and view all the answers

Basophils contribute to inflammation by releasing which of the following?

Histamine, heparin, and serotonin Signup and view all the answers

What is an infection characterized by?

The invasion and multiplication of pathogenic microorganisms. Signup and view all the answers

Which leukocyte is essential for the adaptive immune response?

Lymphocytes Signup and view all the answers

What process do neutrophils primarily perform during an inflammatory response?

Phagocytosis Signup and view all the answers

Which scenario would typically NOT result in inflammation?

A healthy individual with skin colonization by normal flora. Signup and view all the answers

What role does the coagulation cascade play in the body?

It plays a crucial role in hemostasis. Signup and view all the answers

What causes the redness (Rubor) observed during inflammation?

Vasodilation of blood vessels leading to increased blood flow Signup and view all the answers

Which chemical mediators are primarily responsible for stimulating pain (Dolor) during inflammation?

Prostaglandins and bradykinin Signup and view all the answers

What mechanism primarily leads to the swelling (Tumor) associated with inflammation?

Accumulation of exudate in tissue spaces Signup and view all the answers

What is diapedesis in the context of inflammation?

The movement of leukocytes from the bloodstream into inflamed tissue Signup and view all the answers

What term describes the loss of function (Functio Laesa) due to inflammation?

Pain, swelling, and tissue damage Signup and view all the answers

Which feature distinguishes acute inflammation from chronic inflammation?

Duration of the inflammation process Signup and view all the answers

What role does increased vascular permeability play during inflammation?

Allows entry of proteins and leukocytes into tissues Signup and view all the answers

How does calor (heat) develop in inflamed tissues?

From metabolic activity and increased blood flow Signup and view all the answers

What occurs when acute inflammation does not resolve the cause of injury?

Chronic inflammation develops Signup and view all the answers

Which immune cells are primarily involved in chronic inflammation?

Macrophages and lymphocytes Signup and view all the answers

Which mediator is responsible for causing vasodilation and increased vascular permeability?

Histamine Signup and view all the answers

What does the cyclooxygenase pathway produce?

Prostaglandins Signup and view all the answers

What is the role of cytokines in inflammation?

Regulate the immune response Signup and view all the answers

Which process leads to the production of leukotrienes?

Arachidonic Acid Pathway Signup and view all the answers

What is the primary function of Platelet-Activating Factor (PAF)?

Increase vascular permeability Signup and view all the answers

Which growth factor is known for promoting cell proliferation and angiogenesis?

Fibroblast growth factor (FGF) Signup and view all the answers

What is the primary function of Nitric Oxide (NO) in the body?

Vasodilation Signup and view all the answers

Which process initiates the intrinsic pathway of the coagulation cascade?

Damage to the blood vessel Signup and view all the answers

What role does thrombin play in the coagulation process?

It converts fibrinogen to fibrin Signup and view all the answers

Which pathway forms a stable clot during coagulation?

Coagulation cascade Signup and view all the answers

During which phase is the temporary platelet plug formed?

Platelet plug formation Signup and view all the answers

What is the primary purpose of fibrinolysis?

To dissolve clots after healing Signup and view all the answers

Which factor is crucial for both the intrinsic pathway and the common pathway of coagulation?

Factor X Signup and view all the answers

Which of the following substances has antimicrobial properties?

Nitric Oxide (NO) Signup and view all the answers

Which cell type is the first responder to an acute inflammatory event?

Neutrophils Signup and view all the answers

What role does histamine play in the inflammatory response?

Increases vascular permeability and causes vasodilation Signup and view all the answers

Which plasma mediator is produced via the cyclooxygenase pathway from arachidonic acid?

Prostaglandins Signup and view all the answers

Which factor initiates the extrinsic pathway of the coagulation cascade?

Tissue factor (Factor III) Signup and view all the answers

What is a potential complication if acute appendicitis inflammation is not resolved?

Perforation leading to peritonitis Signup and view all the answers

In the context of deep vein thrombosis (DVT), how can inflammation exacerbate the condition?

By increasing blood viscosity and promoting clot formation Signup and view all the answers

What is a hallmark feature of the inflammatory response in acute appendicitis?

Infiltration of neutrophils Signup and view all the answers

Study Notes

Inflammation, Immunology, and Coagulation

Inflammation, immunology, and coagulation are interconnected defence mechanisms
This unit covers key concepts, terminology, and physiological processes related to these mechanisms
Includes a detailed exploration of the coagulation cascade and its role in homeostasis

Inflammation Terminology and Concepts

Acute Inflammation

Definition: The body's immediate response to injury or infection, with a rapid onset and typically resolves in a few days
Examples: Sore throat, skin reactions, burns, insect bites, acute appendicitis

Chronic Inflammation

Definition: A prolonged inflammatory response lasting weeks, months, or years
Occurs when the initial acute response fails to eliminate the cause of injury
Examples: Viral infections (Hepatitis B and C), exposure to toxins (asbestos), allergies, autoimmune diseases

Inflammation Terminology

Colonisation: Bacteria presence on a body surface without causing disease or inflammation
Contamination: Microorganisms on a surface, object, or in a wound, without causing infection or inflammation
Inflammation: The body's response to harmful stimuli, involving immune cell activation, increased blood flow, and chemical mediator release to initiate healing
Infection: Pathogenic microorganisms invading and multiplying, leading to inflammation, and clinical symptoms like fever, pus, and tissue damage
-itis: Suffix denoting inflammation (e.g., appendicitis, dermatitis)

Key Cells Involved in Inflammation

Red Blood Cells (RBCs) or Erythrocytes

Function: Transport oxygen and remove carbon dioxide; not directly involved in inflammation

Platelets or Thrombocytes

Function: Key role in blood clotting and wound healing, releasing growth factors and cytokines that contribute to the inflammatory response and tissue repair

White Blood Cells (WBCs) or Leukocytes

Function: Primary cells involved in the immune response and inflammation
Granulocytes:
Neutrophils: Most abundant, first responders to infection, performing phagocytosis
Eosinophils: Involved in fighting parasites and allergic responses
Basophils: Least common, release histamine, heparin, and serotonin
Agranulocytes:
Lymphocytes: Crucial for the adaptive immune response. Including B cells producing antibodies and T cells directly killing infected cells or coordinating immune response
Monocytes: Circulate in blood, differentiating into macrophages or dendritic cells to perform phagocytosis, antigen presentation, and cytokine secretion

The Cardinal Signs of Inflammation

Rubor (Redness): Increased blood flow due to vasodilation
Calor (Heat): Increased blood flow and metabolic activity of inflammatory cells
Tumor (Swelling): Exudate accumulation due to increased vascular permeability
Dolor (Pain): Release of chemicals (e.g., prostaglandins, bradykinin) stimulating nerve endings
Functio Laesa (Dysfunction): Loss of function due to pain, swelling, and tissue damage

Injury and Inflammation Process

Exudate and Vascular Permeability: Chemical mediators cause vasodilation and increased permeability, allowing proteins and leukocytes to exit blood vessels and enter affected tissues.
Disassembly of Cell Junctions: Increased vascular permeability facilitated by endothelial cell junction disassembly
Diapedesis: Movement of leukocytes from bloodstream into inflamed tissue.

Plasma Mediators of Inflammation

Histamine: Released by basophils, mast cells, and platelets, causing vasodilation and increased vascular permeability
Serotonin: Released by platelets, similar to histamine in function
Arachidonic Acid Pathway:
Cyclooxygenase Pathway: Produces prostaglandins (pain, fever, inflammation)
Lipoxygenase Pathway: Produces leukotrienes (bronchoconstriction, increased permeability, chemotaxis)
Platelet-Activating Factor (PAF): Produced by various cells, enhancing leukocyte adhesion, increasing vascular permeability, and stimulating mediator release.
Growth Factors: Proteins (e.g., TGF-β, FGF) promoting tissue repair
Cytokines: Signaling proteins (e.g. IL-1, IL-6, TNF-α) regulating immune response, promoting inflammation, cell recruitment and activation
Nitric Oxide (NO): Vasodilator, with antimicrobial properties

Coagulation and Its Role in Inflammation

Processes involved in haemostasis:
Vascular Spasm: Immediate vasoconstriction to reduce blood flow
Platelet Plug Formation: Platelets adhering to exposed collagen, creating temporary plug
Coagulation Cascade: Enzymatic reactions converting fibrinogen to fibrin, forming stable clot (intrinsic & extrinsic pathways and common pathway)
Coagulation and inflammation are interlinked; e.g., thrombin has pro-inflammatory effects
Fibrinolysis: Process of clot dissolution (plasminogen converts to plasmin, breaking down fibrin)

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Description

This quiz covers essential concepts in human immunology, focusing on the roles of blood cells and inflammatory responses. Test your knowledge on red and white blood cells, inflammation characteristics, and immune system functions. Perfect for students studying biology or healthcare.