immune system Flashcards
(26 cards)
What are the two main components of the immune system?
Innate Immunity: Provides a rapid, non-specific response to pathogens.
Adaptive Immunity: Provides a delayed, specific response to pathogens and has memory.
What are the key differences between innate immunity and adaptive immunity?
Innate immunity is non-specific, provides the first line of defense, and includes barriers (e.g., skin) and immune cells (e.g., macrophages).
Adaptive immunity is specific, slower to develop, and includes T-cells and B-cells, providing long-term immunity.
What are the key immune cells involved in innate immunity?
Macrophages: Phagocytose pathogens and release cytokines.
Neutrophils: First responders to infection, performing phagocytosis.
Dendritic cells: Act as antigen-presenting cells to activate the adaptive immune system.
Natural Killer (NK) cells: Attack infected or cancerous cells.
What role do cytokines play in the immune system?
Cytokines are signaling molecules that regulate the immune response by promoting inflammation, recruiting immune cells, and regulating the activity of other immune components.
What is adaptive immunity, and what are its components?
Adaptive immunity is a specific immune response that targets specific pathogens and includes T-cells (cell-mediated immunity) and B-cells (humoral immunity), with the ability to develop immunological memory.
What are T-cells, and how do they function in the immune system?
T-cells are lymphocytes involved in cell-mediated immunity.
Cytotoxic T-cells kill infected cells directly.
Helper T-cells activate other immune cells (e.g., B-cells, macrophages).
What is the function of B-cells in the immune response?
B-cells are responsible for producing antibodies (immunoglobulins) that target specific antigens (e.g., pathogens), helping to neutralize or mark them for destruction by other immune cells.
What are the different classes of antibodies (immunoglobulins), and what are their functions?
IgG: Most common, provides long-term immunity, neutralizes pathogens.
IgA: Found in mucosal areas (e.g., eyes, respiratory tract), protects against local infections.
IgM: First antibody produced during an initial immune response.
IgE: Involved in allergic reactions and parasite infections.
IgD: Found on B-cell surfaces, plays a role in immune signaling.
How do antibodies function to protect the body from pathogens?
Antibodies bind to antigens on pathogens, neutralizing them directly, preventing them from entering host cells, or marking them for destruction by immune cells like macrophages and neutrophils.
What is the role of Major Histocompatibility Complex (MHC) in immune function?
MHC proteins are responsible for presenting antigen fragments to T-cells, enabling them to recognize and target infected cells.
What is the process of phagocytosis, and how is it important in immune defense?
Phagocytosis is the process by which immune cells like macrophages and neutrophils engulf and digest pathogens, removing them from the body and initiating immune responses.
What is hypersensitivity, and how does it affect the body?
Hypersensitivity is an exaggerated immune response to harmless substances (e.g., pollen, pet dander), leading to inflammation and tissue damage. It includes allergic reactions such as allergic conjunctivitis.
What is Type I hypersensitivity, and how does it manifest in ocular health?
Type I hypersensitivity is an immediate allergic reaction, mediated by IgE antibodies.
Symptoms include itchy eyes, redness, swelling, and watery eyes (e.g., allergic conjunctivitis).
What is anaphylaxis, and what ocular symptoms may occur during anaphylactic shock?
Anaphylaxis is a severe Type I hypersensitivity reaction, leading to widespread histamine release. Ocular symptoms include swelling, itching, and conjunctival redness
What is the role of mast cells in allergic reactions?
Mast cells are immune cells that release histamine and other chemicals during allergic reactions, leading to inflammation, itching, and vasodilation.
What are the common ocular manifestations of allergic reactions?
Common ocular manifestations include allergic conjunctivitis, itchy eyes, watery discharge, and redness due to histamine release.
How is ocular allergy treated?
Treatment includes antihistamines, mast cell stabilizers (e.g., ketotifen), and topical steroids to reduce inflammation and control symptoms like redness and swelling.
What is the significance of immunomodulatory drugs in managing ocular diseases?
Immunomodulatory drugs like cyclosporine A can help reduce inflammation in chronic ocular conditions like dry eye disease and allergic conjunctivitis by modulating the immune response.
How do the immune system and ocular health interconnect?
The immune system protects the eyes from pathogens through innate and adaptive responses, but overactive immune responses can lead to ocular diseases like allergic conjunctivitis, keratitis, and uveitis.
‘non-specific’ example of the ‘first line defence’
response of the innate immune system?
Normal microbiota on the skin’s surface
features of the adaptive immune system?
Distinguish self from non-self
Attack and destroy
Memory of the encounter must remain
Produce specific antibodies
features of an antibody?
it containsa constant region
it contains a hinge region
it contains a variable region
it is very non-specific
type I hypersensitivity
response involves:
the degranulation of a mast cell
