1.04 UTF-8 0 0 0 on T cells that bind vascular adhesion molecule carbohydrates known as addressins 2 selectins 1 molecule on the surface of endotheliol cells--bound by selectins 2 addressins 1 additional interaction between cells and HEV is mediated by these which are expressed on T cells that bind ICAMs 2 integrins 1 CD28 must bind either ____________ or ___________ for co-stimulation 2 CD80 (B7.1) or CD86 (B7.2) on the APC 1 microbial components enhance responses, this process is called__________ 2 adjuvant activity This provides a context for responses and helps distinguish responses against viral versus commensal bacteria 1 Clusters of TCR and adhesion molecules aggregate on membrane, forming patches known as 2 lipid rafts 1 On the cytoplasmic side of the CD3 subunits, proteins contain motifs for kinases, known as 2 immunoreceptor tyrosine-based activation motifs ITAMs 1 Signals through the TCR are passed by a phospho-relay system using... 2 kinases and phosphatases 1 IL-2 induction requires BOTH ____________________ as signals 2 TCR and CD28 signals 1 Signals must be delivered in a time-ordered fashion. This prevents 2 self-reaction or reaction before infection 1 Ligation of the TCR by MHC-peptide WITHOUT co-stimulation leads to 2 anergy 1 Anergic T cells do not respond to subsequent signals and do not make 2 IL-2 1 TH1 or TH2 cell split is a result of the 2 cytokine environment as these cells mature 1 a high affinity CD28 homologue that binds to CD80/86 to control proliferation 2 CTLA4 1 for regulatory reasons, the stability of IL-2 mRNA is _________ until CD28 co-stimulation 2 low 1 production of IL-2R indirectly leads to mitosis and transcription and translation of ____________ 2 high affinity IL-2R subunit immunosuppressive drugs target this step 1 innate responses provide cytokines early in responses while ___________________ add cytokines later in responses 2 other TH1 or TH2 cells 1 TH1 cells favor _______________ immunity 2 cell mediated 1 TH2 cells favor ____________________ immunity 2 humoral (Ig) 1 what are the three main commentents to cell-mediated immunity 2 response by CD8+CTL response by macrophages genreation of more TH1 1 what are the two main responses to humoral immunity 2 favor maturation of B cells including class switching generation of more TH2 cells 1 Leprosy infection has two responses; what are they and what are their effects 2 TH1-mediated response limits bacteria but with minimal damage to tissues TH2-mediated response can’t control the bacteria, leading to fatal tissue destruction 1 Most effectors secrete __________ while only cytolytic cells secrete ______________ 2 cytokines both cytokines and cytotoxins 1 Interleukins are made by ___________ while lymphokines are made by ____________ 2 T cells both B&T cells 1 Help fine-tune local responses and control the tempo of response Usually short-lived Can be regulated by production of either cytokine or cytokine receptor 2 cytokines 1 Can be regulated by production of either cytokine or cytokine receptor 2 cytokines 1 Eradication of infected cells harboring pathogens or tumor cells Eliminates pathogen factories Essential in fighting intracellular pathogen infection, especially viruses 2 cytotoxins 1 leads to inflammation, recruiting monocytes to the tissue 2 necrosis 1 Cytotoxins Apoptotic pathway: 4 steps 2 Initiation signal Nuclear condensation Chromosomal fragmentation Membrane “blebbing” 1 Cytotoxins Two cytotoxic routes: 2 Dysfunction of these systems leads to proliferative syndromes Release of perforin and granzymes Ligation of Fas (AKA FasR = CD95) 1 Two signals required to activate macrophages: 2 Results in active release of mediators and increased antigen-presentation function Mediators can damage host tissue Interferon-gamma (INF-g) from TH1 cells Ligation of CD40 by TH1 CD40L 1 TH1-mediated responses to ___________ leads to granuloma formation in the lungs 2 tuberculosis 1 With time TH2 cells also make ________________, promoting class switching within the developing follicle, promoting plasma cells 2 These cognate interactions should occur between cells with the same antigen specificity IL-4, -5 and -6 1