Immunity and Inflammation Overview

Study Notes

Immunity

Immunity is the body's ability to resist infection and disease.
It involves a complex network of cells, proteins, and organs working together.
Two main types of immunity exist: innate and adaptive.
Innate immunity is the body's first line of defense, providing immediate responses.
Adaptive immunity develops over time and provides a more specific response to specific pathogens.

Inflammation

Inflammation is a complex biological response to harmful stimuli, including pathogens, damaged cells, and irritants.
Characterized by redness, swelling, heat, pain, and often loss of function.
Its purpose is to eliminate the injurious agent, clear out cellular debris, and initiate tissue repair.
Involves various chemical mediators, including histamine and cytokines.
Chronic inflammation can contribute to various diseases.

Histamines

Histamine is a chemical mediator released by mast cells and basophils.
Plays a role in inflammatory responses.
Causes vasodilation and increased vascular permeability.
Also involved in allergic reactions.

Immune Response

The immune response is a coordinated reaction of the immune system to foreign substances or pathogens.
Involves various immune cells and molecules attacking and destroying pathogens.
Involves both innate and adaptive components.
Key components are antigen recognition, cell activation, and elimination of the threat.
Immune response is crucial to protecting the body against diseases.

Antibody Functions

Antibodies, also known as immunoglobulins (Igs), are critical components of the adaptive immune system.
Bind to specific antigens (e.g., proteins or carbohydrates on pathogens).
Neutralize pathogens, preventing them from infecting cells.
Mark pathogens for destruction by other components of the immune system (opsonization).
Activate complement proteins.

Antibody Types

Five main classes of antibodies exist: IgG, IgM, IgA, IgE, and IgD.
Each class has distinct roles and structures.
- IgG is the most abundant, crosses the placenta.
- IgM is the first antibody produced in response to an infection.
- IgA is found in bodily secretions.
- IgE is involved in allergic reactions.
- IgD is less understood, involved in B cell activation.

Antibody Structure

Antibodies are Y-shaped proteins consisting of two identical heavy chains and two identical light chains.
The variable regions of the light and heavy chains form the antigen-binding sites.
The constant regions determine the antibody class (or isotype).
The structure allows for specific binding to antigens.

Natural Killer (NK) Cells

NK cells are lymphocytes that function in the innate immune system.
Kill infected or cancerous cells.
Recognize and eliminate cells displaying abnormalities without prior sensitization.
Release cytotoxic granules that induce cell apoptosis.

Leukocytes

Leukocytes, also known as white blood cells, are crucial components of the immune system.
Various types, including neutrophils, lymphocytes, monocytes, eosinophils, and basophils, with distinct roles in immune responses and inflammation.
Involved in fighting infection and inflammation.

Complement Proteins

Complement proteins are a group of serum proteins that assist antibodies in eliminating pathogens.
Activated in a cascade-like manner, leading to pathogen lysis, opsonization or inflammation.
Can cause pathogen lysis (rupturing) directly.
Enhance the ability of antibodies and phagocytes to clear pathogens.

Description

This quiz covers key concepts related to immunity and inflammation, including the body's mechanisms for resisting disease. Explore innate and adaptive immunity, the inflammatory response, and the role of histamines. Test your understanding of these vital biological processes and their significance in health.