Lecture 6- Integrated biology of the immune system Flashcards
1 example of early innate recognition of 3 main pathogen types
virus- TLR3 for dsDNA
bacteria- NODs for cell wall components
parasites- TLR2 for GPI anchors
some more general responses to infection
inflammatory cell migration to infected tissue
vasodilation and vascular permeability
pain etc
example of how CD4+ cells can aid CD8 activation directly and indirectly
directly- peptide loading onto Th cell MHCI
indirectly- CD4 IL2 production supporting CD8 clonal expansion as 8s can’t produce enough alone
how can B and T cells interact
CD4 providing interactions with B cells that help class switching
innate cells CD4s can interact with
macrophages
6 stages of Plasmodium falciparum infection
mosquito, early human (on route to liver), liver, blood, persistence in blood, second exposure
what happens in mosquito
innate immune response, largely in the gut
production of nitric oxide and antimicrobials (enzymes, other peptides), haematocyte activation for phagocytosis
plasmodium life stage which enters humans
sporozoite
issues with immune response early in human plasmodium infection
too quick to develop a proper response- just complement/phagocytosis which usually won’t eliminate the threat
plasmodium in the liver
‘hide’ in vacuoles in hepatocytes, antibody targeting is difficult
exit when the CD8 response becomes effective from the bits of secreted protein in the cytoplasm
what happens in the blood
merozoite stage so no recognition out of the liver
goes into RBCs, dealt with by macrophages which CD4s can recognise
defence against blood immune mechanisms
EMP proteins make RBCs stick to walls of blood vessels
response to EMPs and counter measure
CD4 can target EMPs, but there is often antigenic variation
