Chronic Inflammation Flashcards
Characteristic cells in chronic inflammation
plasma cells and lymphocytes
CD4+ T-cell costimulatory signal
B7 on APC
CD28 on T-cells
Th1 CD4 T-cells secrete
what
function
Th1 secretes
IFN-γ
activates M1 macrophages, inhibits Th2
Th2 CD4 T-cells secrete
Th2 secretes
IL-4 and IL-5
IL-4: IgE class switching
IL-5: IgA class switching + eosinophil chemotaxis
CD4 cells secrete ________ to activate CD8 cells
IL-2
4 x 2 = 8
CD4 x IL-2 = CD8
Second activation signal for CD8 T-cells
IL-2 from CD4
4 x 2 = 8
CD4 x IL-2 = CD8
Alternative recognition pathway for CD8 cells
FasL recognizes Fas on cells that will die
Mechanism of CD8 killing
perforins and granzymes
perforins: poke holes
granzyes: activate caspaces
Activation of B-cells
primary stimulus
costimulus
1˚: CD4 T-cells on MHC-II
co: CD40
Which IL promote hypermutation and class-switching of B-cells
IL-4 and IL-5
IL-4
source
function
IL-4
from Th2 CD4 cells
class switching of B-cells to IgE
B-cell hypermutation
IL-5
source
function
IL-5
from Th2 CD4 cells
eosinophil recruitment and IgA class switching
B-cell hypermutation
Defining cell in granulomas
epithelioid histiocytes
Caseating vs non-caseating granulomas
caseating: necrotic
non-caseating: non-necrotic
Non-caseating granuloma etiologies
sarcoid cat scratch (stellate) foreign body beryllium Crohn
Caseating granuloma etiologies
Tb
fungi
Epithelioid histiocytes are derived from
macrophages
How to get an epithelioid histiocyte
macrophages act as APCs + secrete IL-2 on Th1s Th1 CD4 cells secrete IFN-γ IFN-γ activates macrophages ==> epithelioid histiocytes **caseating and non-caseating
