the immune system Flashcards
antibody use in Elisa to detect antigen
DIRECT ELISA
attach sample with potential antigens to well
add comp monoclonal antibodies with enzyme attached which bind to antigens if any present
wash well to remove any unbound antibodies
add substrate and enzyme creates products that cause a colour change
use of antibodies in Elisa to detect antigen
SANDWICH METHOD
attach specific MA to well
add sample with potential antigens then wash well
add comp MA with enzyme attached and bind to antigens if any present
wash well to remove unbound antibodies
add substrate - enzyme creates products that cause a colour change
use of antibodies in Elisa to detect antibodies
attach specific antigens to well
add sample with potential antibodies nd wash well
add comp MA with enzyme attached which bind to antibodies if any present
wash week
add substrate enzyme creates products that cause. colour change
purpose of control well in Elisa
compare to test to show only enzymes cause colour change
compare to test to show all unbound antibodies have been washed away
ethical issues with vaccines and MA
testing on animals - harmful
trials on human side effects
how can monoclonal antibodies be used in medical diagnosis
MA - specific tertiary structure
comp to specifc receptor or antigen associated with diagnosis
dye attached to antibody
antibody binds to receptor or antigen forming AA complex
MA used in medical treatment
MA - specific tertiary structure
comp to receptor or antigen only on specific cell type
therapeutic drug attached to antibody
antibody binds to specific cell forming AA complex delivering the drug
what is a MA
antibody produced from genetically identical plasma cells
so they have the same tertiary structure
why are antibiotics ineffective against virus
virus dont have metabolic processes so dont make protiens
virus dont have a murein cell wall
replication of his in t helper cells
hiv AP attachés to receptors on helper t cell
lipid envelope fuses with CSM releasing capsid into cell
capsid uncoats and releases RNA and RT
viral dna incorp into helper T cell dna
viral dna inserted into helper T cell dna
viral protein capsid enzymes are produced
dna transcribed into hiv mrna and those are translated into new hi protiens
virus particles assembled and released into cell via budding
how does hiv cause symptoms of aids
hiv invers and kills helper T cells as multiply rapidly
so helper T cells cant stimulate cytotoxic T cells and B cells and phagocytes
so b plasma cells cant release antibodies for agglutination and destruction of pathogens
IS deteriorates - more susceptible to infections
pathogens reproduce release toxins and damage cells
antigen variability
antigens on pathogen change shape bc gene mutation
no longer immune
b memory cell receptors cant bind or recognise changed antigen on secondary exposure
and septic antibodies cant bind to changed antigen
active immunity
initial exposure to antigen
memory cells involved
antibody produced and secreted by b plasma cells
slower and takes loner to develop
long term immunity as antibody can be produced in response to specific antigen again
passive immunity
no exposure to antigen
no memory cells involved
antibody introduced from another organism
fast acting but short term immunity as antibody is hydrolysed
what are vaccines
injection of antigens from dead or weakened antigens
stimulating formation of memory cells
