Immuology Flashcards
What bond do lysozymes cleave
beta 1, 4 glycosidic bond
What are the 4 organs/tissues of the lymphoid system
lymph node, thymus, spleen, diffuse lymphoid tissue
What are the 3 lymphatic tissues
MALT, GALT, BALT
What is the purpose of primary lymphoid organs
development and maturation of lymphocytes
Where do T and B cells mature
Thymus, fetal liver & bone marrow
What is similar and different between spleen and lymph node
Both filter blood and remove antigens, spleen random while lymph node organized
What do the cortex paracortex, medulla of the lymph node contain
cortex - B cells, macrophages, epithelial reticular cells
paracortex - T cells
medulla - plasma cells
What is the red and white pulp of the spleen
red - sinusoids
white - WBC, lymphocytes
What is septa (trabeculae)
connective tissue that separates lobes into lobules of thymus
What are the 2 main components of the thymus
parenchyma (cellular), stroma (connective)
What is the role of ERC 1, 2, and 3
ERC1: forms blood-thymus barrier
ERC2: mid-cortex, desmosome junctions
ERC3: deep in cortex, contains T cells
Which ERC educate T cells
ERC2 and 3
What is positive selection
double negative T cells undergo beta selection to express CD4 and CD8
strong binding to MHC are selected
What is negative selection
Single positive T cells that bind too strong to MHC + antigens undergo apoptosis
Those that bind weakly become effectors
Those that bind intermediate become regulatory cells
What do mast cells and neutrophils/macrophages/DCs do
release bioactive chemicals, signals other cells and phagocytose pathogens
What are 4 major PRRs
membrane bound C-type lectin, toll like receptors
cytosolic NOD like, RIG1-like receptors
What is main role of IgM, IgG, IgA, IgE, and IgD
stops infections, protects newborns, mucosal defense, allergy, trigger B cells
Where is MHC class I and II found and where does the peptide come from
MHC class I: all cells attract CD8 antigen made by cell
MHC class II: DC, macrophage attract CD4 foreign antigen
What do Th1 and Th2 do
secrete interleukins to stimulate macrophages CTL and NK, and stimulate B cells
What is Type I hypersensitivity
IgE dimers bound to mast cells recognize antigen and degranulates
What is Type IV delayed hypersensitivity
TH1 cells increase and are activated during first exposure and react and release excess inflammatory cytokines second time
