Chronic Inflammation Flashcards
What is chronic inflammation?
it is characterized by lymphocytes and plasma cells in tissue and is a delayed response but more specific. considered to be the adaptive immunity
What causes chronic inflammation
persistent infection, infection with viruses, mycobacteria, parasites and fungi, autoimmune disease, foreign material and some cancers
What activates t cells
Binding of Antigen/MHC complex and additional 2nd signal.
What is the mechanism for activation for CD4 T cell
APC or antigen presenting cells take an extracellular antigen phagocytose, process and present it via MHC class 2 and show to the CD4 T cell. the second signal of the activation is B7 on the APC that bind CD28 and that provides the second signal.
What happens when the CD4 cells are activated
it secretes cytokines that help with inflammation. this help is divided into B cells and CD8 T cells that activate either Th1 and Th2
What is the function of Th1-
it activates the IL-2 ( t cell growth and CD8 t cell activation) and IFN ( macrophage activator).
What is the Th2 function
it helps the B cells with IL4,5 and 10. IL-4 deals with class switching of IgG and IgE IL-5 - eosinophil chemotaxis and activation, maturation of B cells to plasma cells and class switching of IgA) IL-10- inhibits th-1phenotype
how are CD8 activated
it deals with MHC 1. this deals with INTRACELLULAR antigen is process and presented on MHC 1. The second signal that activates is IL-2 from CD4 Th1. this activates the killing of the cytotoxic T cell.
How does CD8 kill
it secretes perforins and granszyme that induce apoptosis of the target cell or they can express FasL that binds to Fas on the target cell activating apoptosis.
What are b lymphocytes?
mmature B cells that are produced in the bone marrow that undergo IgG rearrangment to become naive B cell that express IgM and D.
How are B cells activated
antigen binding by the surface IgM or IgD. also it can go through the antigen/MHC binding complex and the second signal process. it does this through antigen presented to the CD4 MHC class 2 and the second signal coming from CD40 receptor on B cell binds CD40L on helper T cell providing 2nd activation signal.
What does the activation of helper T cells do for B cells
Secrete IL-4 and IL-5
What are the subtypes for B lymphocytes
granulomas and non-granulomas
What is granuloma chronic inflammation
inflammation that is characterized by epithelia histiocytes and is surround by giant cells and rim of lymphocytes and is divided into nocaseating and caseating subtypes
What are the subtypes of granuloma and
Noncaseating and caseating