IMM250H1 Study Guide - Fall 2018, Comprehensive Midterm Notes - Cytokine, Antigen, Antibody
IMM250H1
MIDTERM EXAM
STUDY GUIDE
Fall 2018
Lecture 1: The Iue Syste Fro historical to oder perspectives
The Immune System
• Immune system: a system of tissues, cells and soluble products that recognize, attack and destroy entities
that can endanger our health when they enter our bodies
• Four major classes of pathogens:
1.
Bacteria (e.g. salmonella)
2.
Virus (e.g. rhinovirus)
3.
Fungi
4.
Parasite (e.g. malaria)
Immune Response
• There are 4 stages of immune system and 3 challenges associated with each step
1. Recognition: pathogens are highly varied in structure and evolve quickly
2. Response: pathogens replicate or produce toxins quickly
3. Returning to resting: collateral damage to healthy tissue caused by immune response
Smallpox
• Disease caused by virus variola major - no animal reservoir
o Causes small fluid filed vesicles on skin
• Variolation: inoculation with material from small pox pustule to produce immunity
• vaccination
o Very bad because it spread disease even more
• Edward Jenner paved the road for vaccination when he realized cowpox (attenuated version of small pox)
could produce immunity
Germ Theory of Disease
• Louis Pasteur & Robert Koch began isolating and characterizing organisms that could only bee see under a
microscope
• The germ theory proposed that microbe are organisms too small to be seen by eye, and some cause specific
diseases
• Koch developed techniques for cultivating pure cultures of bacteria
Louis Pasteur
• Realized he could induce acquired immunity in chickens
• He made two major discoveries;
1. Fermentation
2. Pasteurization
• Disproved the spontaneous generation of microorganism
Cellular v Humoral Immunology; A Century-Long Dispute
• Metchnikoff theorized and demonstrated that human white blood cells similarly engulf and destroy
pathogens like bacteria
o Demonstrated that phagocytes represent a first line of defence
o He was a cellularity; believed that phagocytes, not antibodies, played a prominent role in immunity
• Paul Ehrlich was a humoralist and believed soluble anti-toxins(antibodies) were responsible for immunity
o Anti-toxins (according to Ehrlich)
• Anti-toxins were receptors with lock and key structure
• Bind to infectious agent to a anti-toxin would cause release and production of more the anti-
toxin receptors
• He thought that cells express several different anti-toxins which is false
o MacFarlane revised Ehrlich theory with clonal selection hypothesis:
• Each lymphocyte makes one kind of antibody
• “Antigens” stimulate the clonal proliferation of lymphocytes that make an antibody that
recognizes a particular antigen
Lymphocytes
• Two major types of lymphocytes that look the same up until they mature:
1. B cell: Produce antibodies
find more resources at oneclass.com
find more resources at oneclass.com
i. Differentiate into plasma cells
2. T cell: produce cytokines
i. Help antibody production
Strategies used by Immune Cells
• There are several strategies used by immune cells to eliminate infectious agents or protect against infection
o Killer cells which induce cell death in virally-infected cells
o Pre-existing antibodies block access of the virus to its cellular receptor
• Protecting target cells from infection
o Phagocytes ingest extrasellar bacteria
o Degranulating cells (e.g. neutrophil) release granules containing toxic molecules to kill antibody
coated parasites
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Lecture 1: the i(cid:373)(cid:373)u(cid:374)e syste(cid:373) fro(cid:373) historical to (cid:373)oder(cid:374) perspectives. Louis pasteur: realized he could induce acquired immunity in chickens, he made two major discoveries, fermentation, pasteurization, disproved the spontaneous generation of microorganism. Antigens stimulate the clonal proliferation of lymphocytes that make an antibody that recognizes a particular antigen. Lymphocytes: two major types of lymphocytes that look the same up until they mature, b cell: produce antibodies. Differentiate into plasma cells: t cell: produce cytokines. Lecture 2: i(cid:374)(cid:374)ate i(cid:373)(cid:373)u(cid:374)ity: first li(cid:374)e of defe(cid:374)se. Requirements: there are 8 requirements for infectious disease: Invasion through a portal of entry: reservoir, transmission to host, adherence to host tissue, temporary evasion of host defenses, disease: interference with normal host function, exit and transmission. Pylori: causes ulcers - proven by marshall, used to be part of normal microbiota but in late 90s became eradicated through antibiotics. In immunocompromised patients, many free-living bacteria an can cause disease.
