Immune system #1 Flashcards
What are the two ways cells communicate?
directly and indirectly
How do they communicate directly? ex
direct interaction, ex egg and sperm
How do they communicate indirectly? ex
diffusible chemical communication ex. insulin from islet cells from pancreas stimulate other cells in the body to take up glucose from blood
What are the two types of hormones?
Water soluble (amines and peptides) and lipid soluble (steroids)
What is another way for indirect communication?
electrical signals. ex is the electrical current in the heart during each contraction
What are the five threats to our defense system?
pathogens, abnormal cells, dead/damaged cells, foreign substances, and sometimes our own healthy tissues
What are the 5 pathogens?
bacteria, viruses, fungi, protozoa, worms
What is our innate defence system?
not specific to certain pathogens and there is no clonal selection
What is our adaptive immune system?
specific to certain pathogens and there is clonal selection
What are our 5 innate defenses>
barriers (skin)
phagocytes ('cell eaters')
Natural killer cells
inflammatory response (bacterial infections)
feveropsonization
labels attached to cells for recongnization to our immune system
4 properties of adaptive immune system?
specificity, diversity, self/nonself recognition, and memory
antibody and immunoglobin class
antibody is an individual molecule, a similar set of antibodies is an immunoglobin class
what properties do antibodies manifest
specificity and diversity
Two regions of an antibody?
variable region- different in each antibody
constant region- the same in each ig class
epitope
part of the antigenic molecule that bonds the antibody
what substances can be percieved as antigenic by our immune system?
proteins and glycoproteins.
polysaccarhides
How are different antibodies generated?
generated by editing the genes in ig classes of B cells that produce antibodies. this results in a large variety
What are T cell receptors?
glycoproteins located at the surface of T cell
What do t-cells have in common with B cells?
manifest specificty and diversity
bind to antigens
diversity generated by gene rearrangments
Where do B and T cells mature?
B-Bone marrow
T-Thymus
B lymphocyte structure
have antibodies on the outside of the cell that bind to antigens. tells the cell there is a foreign object with that specificity.
Each B cell has its own antigen specificity
B lymphocyte activation?
antigen binding or interaction with helper T cell
Clonal selection
when a B cell or other cell binds with a certain antigen, the cell is cloned
plasma B cells
release antibodies
memory B cells
kept in circulation after an infection and clonal selection to allow for speedy attack when next exposure occurs
What do antibodies do
membrane receptors on B cells
coat viruses and bacteria, preventing epithelia attacthment and allow for macrophage recognition and destruction
Helper T cells
provide links between macrophages, humoural immunity and cell-mediated immunity. Activate B cells and cytotoxic T cells
APCs and MHC
macrophages are antigen-presenting cells (APCs) and is part of the major histocompatibilty complex (MHC) presenting the antigen to helper T cells
cytotoxic T cells
activated by helper T cells and infected cells
poke holes in cells with perforin.
also have a memory component
somatic hypermutation
allow for a greater second response time because it occurs during the proliferation of the memory cells
acquired immunity
immunity from a previous exposure and/or vaccination
passive immunity
antibodies supplied directly from the outside
ANtibodies made in labs
raise antibodies for specific molecules and attach a flourescent label to the antibody
polyclonal antibodies
different epitope specifities and different epitopes of the same antigen
monoclonal antibodies
all have the same epitopic speicificity and bind to one epitope only
What are the A and B antigens on RBCs?
oligosaccharide chains attached to glycoproteins and glycolipids
what does type A blood have?
A antigen and produces anti-B antibodies
what does type B blood have?
B antigen and produces anti-A antibodies
Type AB blood?
has both A and B antigens but produces no antobodies
Type O blood?
has no antigens but produces both anti-A and anti-B antibodies
Universal donor?
Type O
Universal receiver?
Type AB
glutination
the clumping of blood cells when antigens react with antibodies
