PHIL 1000X Study Guide - Final Guide: Abo Blood Group System, Natural Killer Cell, Allergen
10 May 2018
School
Department
Course
Professor
BLOCK XB
MODULE X5 - DEFENCE MECHANISMS
UNIT 3
Immune Response Pathways
Unit Objectives
When you have finished this unit, you should be able to:
1. Describe a typical response to a bacterial infection.
a. Activation of the complement system
i. -> chemotaxins attract leukocytes and opsonins enhance phagocytosis
ii. Vasoactive chemicals (eg histamine) dilate blood vessels and increase
capillary permeability (swollen and red
iii. Membrane attack complex molecules -> cell lysing
b. Activity of phagocytes
i. If bacteria is encapsulated, hides it from recognition by macrophage
receptors
ii. Opsonins (LIKE ANTIBODIES) coat -> phagocytosis
c. Acquired immune system
i. If antibodies against bacteria already present, enhance innate response
ii. Present antigen to memory cells -> make more antibodies
d. Repair
i. cytokines!
2. Describe what happens when a host cell is infected by a virus.
a. Humoral immunity (antibodies) NO LONGER EFFECTIVE
b. Must use cytotoxic t cells and NK cells
3. Describe a typical allergic reaction.
Note: An allergy is an inflammatory immune response to a nonpathogenic antigen.
i. The allergen is an antigen that is typically not harmful to the body.
● Allergen ingested and processed by APC (MHC II)
● Activates helper T cells
● Activates B lymphocyte
● Activated B lymphocytes become memory and plasma cells
● Upon reexposure, b and t work more quickly
4. Explain how ABO blood groups determine what blood can be used for a transfusion.
Document Summary
When you have finished this unit, you should be able to: describe a typical response to a bacterial infection, activation of the complement system i. > chemotaxins attract leukocytes and opsonins enhance phagocytosis: vasoactive chemicals (eg histamine) dilate blood vessels and increase capillary permeability (swollen and red, membrane attack complex molecules -> cell lysing, activity of phagocytes i. If bacteria is encapsulated, hides it from recognition by macrophage receptors: opsonins (like antibodies) coat -> phagocytosis, acquired immune system. Note: an allergy is an inflammatory immune response to a nonpathogenic antigen: the allergen is an antigen that is typically not harmful to the body. Allergen ingested and processed by apc (mhc ii) Activated b lymphocytes become memory and plasma cells.
