Production of ab and activation of Macrophages and Cytotoxic T Celis T-Dependent T-Independent BIOL 533 Lecture 7
BIOL 533 2 Lecture 7 Production of Ab and Activation of Macrophages and Cytotoxic T Cells • T-Dependent • T-Independent
T-Dependent Activation带 EXtracellular pathogens Digested by macrophage--Ag complexed MHC class ii (present only in macrophage and few other cell types) Stimulates helper T cells(tH2) to find B cells, recognize particular peptide fragment ab Helper T cells(CD4+ cells; THi) produces FNv and activates macrophage BIOL 533 Lecture 7
BIOL 533 3 Lecture 7 T-Dependent Activation • Extracellular pathogens – Digested by macrophage—Ag complexed MHC class II (present only in macrophage and few other cell types) – Stimulates helper T cells (TH2 ) to find B cells, recognize particular peptide fragment Ab – Helper T cells (CD4+ cells; TH1 ) produces IFN and activates macrophage
T-Dependent Activation带 Intracellular pathogens Digested when released from dying host cell Peptide Ag presented on MHC class I Proliferation of cytotoxic T cells(CD8+) BIOL 533 Lecture 7
BIOL 533 4 Lecture 7 T-Dependent Activation • Intracellular pathogens – Digested when released from dying host cell – Peptide Ag presented on MHC class I – Proliferation of cytotoxic T cells (CD8+)
a Processing CHO and Lipid Ag y LPS interacts directly with B cells (independent of T cells CHO Ag largely independent of T cells, but some involvement(production of cytokines; necessary for maximal B cell activity) BIOL 533 Lecture 7
BIOL 533 5 Lecture 7 Processing CHO and Lipid Ag • LPS interacts directly with B cells (independent of T cells) • CHO Ag largely independent of T cells, but some involvement (production of cytokines; necessary for maximal B cell activity)
T-Dependent mechanism Macrophage presents part of Ag and own class II MHC to T-helper cell(signal #1) Also makes ILl 6 signal #2) IL1 6 stimulates t cell clone to divide and make il2 4-6 ILl also stimulates hypothalamus to raise body temperature, enhancing T cell action BIOL 533 Lecture 7
BIOL 533 6 Lecture 7 T-Dependent Mechanism • Macrophage presents part of Ag and own class II MHC to T-helper cell (signal #1) • Also makes IL1 6 (signal #2) – IL1 6 stimulates T cell clone to divide and make IL2 4-6 – IL1 also stimulates hypothalamus to raise body temperature, enhancing T cell action