HUBS 191 Lecture 37 Flashcards
(18 cards)
what is SCID
severe combined immunodeficiency - an X linked disease in which patients lack function T and B cells
what does HIV stand for
human immunodeficiency virus
what are opportunistic pathogens
pathogens that are normally harmless to individuals with a healthy immune system but can cause disease in someone with a weakened immune system
what does HIV do to the body
it targets the CD4 molecule on CD4 cells and leads to the loss of CD4 T cells which impacts on immunity
what is rheumatoid arthritis
an autoimmune disorder that primarily affects joints - auto reactive T and B cells attack self antigens present in the joints
what causes diabetes type 1
the destruction of beta cells (insulin secreting cells) - other islet cell of the pancreas escape autoimmune attack
are autoimmune disease specific
some autoimmune diseases are so specific they target specific molecules whereas others are more generic and target whole organs
what are allergens
antigens that trigger allergy - these are normally harmless environmental antigens
how do chemicals induce allergy
by modifying proteins in our bodies so they look foreign to mast cells
in the beginning of the allergic response dendritic cells take up antigens and ________
activate CD4 T helper cells in the draining lymph node
during the allergic response CD4 T cells (that are allergen specific) provide cytokine help for _______________
B cells which are expressing antibody that can bind to an allergen - these B cells then form IgE secreting plasma cells
during the allergic response IgE binds to ______
Fc receptors on mast cells
during the allergic response peanut allergens trigger mast cells to release __________
histamines and other inflammatory mediators
a lot of cells have Fc receptors but mast cells have specific Fc receptors that recognise ____
IgE
antibody binding to antigen will induce a change in the antibody structure so it becomes _______
more tightly bound to the Fc receptors
FcR facilitate a number of functions including…
phagocytosis and mast cell activation
how do we prevent free antibody from blocking up Fc receptors
the binding of antibody to antigen induces a conformational change in the antibody structure so it binds better to an FcR.
when does class/isotype switching occur
during an immune response
