Revision session Flashcards
(25 cards)
Where do lymphocytes develop, mature and rearrnge their gene receptors
Where do lymphocytes develop, mature and rearrnge their gene receptors
primary lymphoid organs; bone marrow, bursa in birds and thymus
humoral immunity cell mediate immunity ab and Ig isotopes
Adaptive immunity;
Are monocytes in the peripheral blood phagocytes?
Are monocytes in the peripheral blood phagocytes? yes phagocytic cells include monocytes; in the blood macrophages in tissue neutrophils dendritic cells
To help B cells, do CD4 T cells need to have already seen their ag?
To help B cells, do CD4 T cells need to have already seen their ag? yes native lymphocytes can’t mediate effector functions naive CD4 T cells must recognise its ag on MHC-II on an APC this leads to activation, proliferation, differentiation, effector T helper cells/ memory cells which mediate their effector functions through cytokines release
List the different types of T helper T cells and explain what they do?
- T helper 1 cells; activate macrophages help CD8 T cells to activate and differentiate into CLTs help B cells to isotope switch to certain ig isotope (certain IgG subclasses)
- T helper 2 cells; help B cell produce ab and isotype switching (to IgE) recruit and activate eosinophils, mast cells, stimuli mucous production , smooth muscle contraction important for helminth (parasitic worm) immunity and type 1 hypersensitive (allergy)
Can B cells act as APCs and activate naive CD4 T cells
not usually but under usually circumstances B cells can present ag activated naive CD4 T cells its professional APC=DC that activate naive T cells
True or false naive T cells are not killer?
True naive T cells are not killer not yet no naive CD8 T cell must recognise its ag on MHC I which leads to proliferation, differentiation with help from TH 1 cell, CTLs (kill against viral infections) or memory CD8 cells
Does a DC need to be infect in order to present peptide ag on MHC I
no, just needs to be an infected DC
For exogenous and endogenous Ag peptides explain them, list what they are loaded on to and what recognised them
-exogenous Ag peptides (ag coming in from outside the APC) are loaded onto MHC class II and recognised by CD4 T cells -endogenous Ag peptides (ag within the cell) are loaded onto MHC class 1 and recognised by CD8 T cell
List the ACPs
ACP DC macrophages B cells
Discuss the passive transfer of Ab in neonates
you need colostrum intake because its required for protection against septicaemia disease (igG absorption provides systemic immunity) milk ensures protection of GIT (IgA and IgG)
For extracellular give 2 sites of infection, organisms and protective immunity
For Intracellular give 2 sites of infection, organisms and protective immunity
Define the following terms
Philia pr cyostis
penia
philia or cytosis= increase or high
penia= decrease or low
auto or self reactive ab tagret the animsl own RBC
this autoimmune disease cause by type 3 hypersensitivity- ab mediated cytoxic hypersensitivty
Where do naive lymphocytes encounter their ag and are stimulated to differentiate into effector and memory cells?
Where do naive lymphocytes encounter their ag and are stimulated to differentiate into effector and memory cells?
secondary lymphoid organs; spleen lymph nodes and MALT
For the innate and adpative immuntiy state lvel of specficity
when it occurs
memory?
cells present
Innate
cells; phagocytic (neutrophils & macrophages) & NK cells
nonspecifc- same resonse works against many pathogens
occurs early; 1st line of defence
non memory
Adaptive
cells T and B cells
highly specific; custom response to pathogen
occurs later
memory
What are the 2 types of adaptive immunity?
Humoral immuntiy; Ab, B cells and plasma cells which produce B cells
B cells need help form T cells to make ab
Cell-mediated immunity; T cells
2 types; helper T cells; help B cells to amke ab and help activate cytotoxic T cells and have CD4
killer or cytotoxic T cells; kill infected cells or tumour cells, have CD8
Briefly describe inflammation
inflammation
nonspefic respone to tissue injury (burns etc.)
cells of immne system and products concetrate @ site of infection or tissue damage
aid in erication and repair
3 events; blood supply to site increases
capillary permeability increases= solubel mediators reach site
leucocytes migrate from blood to affected tissue
What is PRR
PRR; pattern recognition receptors
can tell self from non self
examples of these cells are senor cells (macrophages, DCs)
What is the complement system?
complement system is a group of cells
these proteins circulate in the blood or can be induced
functions;
help recruit phagoctyes to site of inflammation and active them
bind to receptors on phagocytes to remove agent of infection
important in inflammaotry response of innate and adpative
proteins include C3, C4, C5
What are actue phase proteins
Acute phase proteins
bacteria induces macrophages to produce IL6 whihc acts on hepaocytes to induce synthesis of acute phase proteins
e. g
- C reactive protein whihc binds to phosphocholine on bactrial surfaces acting as an opsonin and activating complement
- mannose-binding lectin binds mannose residues on bacterial surfaces,acting as an opsonin and also activating complement
What is a cytokine?
any of a number of substances, such as interferon, interleukin, and growth factors, which are secreted by certain cells of the immune system and have an effect on other cells
What is Ag presentation and APCs
process of presenting an Ag to a T cell is done via MHC molecule
B cell gets Ag and presents it to T cell via MHC
APC will digest ag into smaller peptide fragments
APC then display peptide Ag on their surface bound with other molecules called MHC and this causes the T cell to become active
