Lymphoid Organs and Cell Migration Flashcards
what cells are in involved in innate immunity
phagocytes and APCs
what cells are involved in adaptive immunity
B cell and T cells
what are the primary lymphoid organs
bone marrow and thymus
where do all immune cells except t cells develop
bone marrow
where do t cells develop
thymus
what are the secondary lymphoid organs
lymph nodes
spleen
GALT
what influences stem cell differentiation
cell to cell contact
presence of cytokines
what are HSCs?
totipotent haemopoietic stem cell
what produces cytokines
T helper cells and APCs
what are cytokines?
intercellular communication molecules
what are pleiotropic cytokines?
cytokines with many functions
what are redundant cytokines?
cytokines with similar functions
what is the target cell of Th1
macrophages
what cytokines are released by Th1
IL2, IFNy, TNFa
what is the target cell of Tfh?
B cells - autoimmunity
how do B cells produce functional B cell surface receptors?
recombine heavy and light chain genes
what are the two regions of the thymus
outer cortex (immature) inner medulla (mature)
what is the spleen composed of?
white pulp- T and B cells
red pulp - removal of RBCs and platelets
what is the function of the lymph nodes
filter antigens from interstitial fluid and lymph
what is MALT
mucosal lymphoid tissue
what are the 3 component of the inflammatory response
- increased blood supply
- increased capillary permeability
- leucocyte migration
what cells appear first in inflammation
neutrophils
APCs
CTLs
B lymphocytes
what is chemotaxis
directional migration of cells up a concentration gradient of chemotactic molecules
what is chemokinesis
no directional movement of cells
what are the chemotactic molecules
c5a - complement protein
chemokines
bacterial peptide -f-met-leu-phe
