IFN-γ In presence of infection, secreted to tell the cells to change proteasomes to favor peptides that bind to MHC class Ican induce expression of MHC class II on some cells that usually don't produce theminhibits replications of viruses when secreted by CD8 T cellsincreases processing and presentation of viral antigen by MHC class I moleculesactivates macrophages in vicinity of cytotoxic T cellscharacteristic TH1 cytokine that switches B cells to make IgG1; strong opsonizing Ab in humansPA28 binds to both ends of proteasome to form the immunoproteasomeTAP "transporter associated with antigen processing"embedded in membrane; helps peptides cross ER membraneheterodimer of 2 polypeptide chains (TAP-1 and TAP-2)dependent on ATPusually bind peptides 8 or more amino acids longcalnexin calcium-dependent lectinkeeps the MHC class I heavy chains (alpha chains) partly-folded in the ERreleased when heavy chain binds to beta-2-microglobulinERp57 and tapasin bridging protein complex that binds to MHC class I heavy chain and TAP-1 subunitERAP "endoplasmic reticulum aminopeptidase"takes off some AAs if the peptide is too long for the MHCInvariant chain prevents peptides in the ER from binding to MHC class II also delivers MHC class II moleules to endocytic vesiclesHLA-DM removed CLIP (the small fragment of the invariant chain left behind)helps bind peptidesVpreB and λ5 form surrogate light chain (BCR development) λ5 substitutes for L-chain constant regionVpreB substitutes for V regionVLA-4 on pro-B cells; binds to VCAM-1 on stromal cellsKit on B cell; binds to stem cell-factor (SCF) on stromal cellactivation of Kit causes B cell to proliferateIL-7 at later stages of maturation, B cells require it for growth and proliferationTdT "terminal deoxynucleotidyl transferase"adds N nucleotides at junctions between gene segmentsexpressed in pro-B cells and turned off in small pre-B cellsIL-10 controls self-renewal of b-1 cells (prenatal B cells)Important Letters and Numberstells centrocytes to become plasma cells (when infection is bad)CCL21 chemokine that attracts immature B cells to HEV (lymph node)CCL21 and CCL19 together, attract B cells into lymph node (T-cell area)produced in lymphoid tissue; draw T-cells into lymph node by binding to CCR7, the receptor on the T-cellCXCL13 attracts B cells into primary follicleIL-7 receptor on T-cells; binds IL-7 secreted by thymic stromal cellshelps tell the T-cell what to do next in maturationNotch-1 signals are sent through it at all stages of maturation to drive T-cell in differentiation ensures that T-cells carry on T-cell development, not B-cell developmentpTα functional Beta chain binds to it as a test; similar function as surrogate light chain in B-cell developmentpre-T-cell receptor surrogate alpha chain (preTα) + CD3 proteins + ζ chainCD25 expressed by regulatory CD4 T-cellsFoxP3 transcriptional repressor unique to regulatory T-cellsDEC 205 receptors used by immature dendritic cells to phagocytose microbial antigensL-selectin on T-cell surface and B-cell surfaceinteracts with two vascular addressins on surface of HEV venules (CD34 and GlyCAM-1)LFA-1 on lymphocyte surfaceactivated by chemokines; enable it to bind to ICAM-1 on endothelial cellon T-cell, LFA-1 binds to ICAM-1 or ICAM-2 on APCICAM-3 on T-cell, binds to LFA-1 on APCalso binds to DC-SIGN on the activated dendritic cell to strengthen adhesionCD2 on T cell; binds to LFA-3 on APCstrengthens adhesion between T-cell and APCS1P (sphingosine 1-phosphate)draws T-cells out of lymph node if they don't find their specific antigenexpression of S1P receptors by T-cells is suppressed if they have met their antigenCD28 on T cell; binds to B7 on APC (B7 only expressed during infection)provides signal 2 (necessary for T-cell activation)CTLA-4 another B7 receptor on T-cellsbinds B7 twentyfold more strongly than does CD28B7 binding CD28 activates T cell; B7 binding CTLA-4 slows down activation and limits cell proliferationCCL18 chemokine secreted by activated dendritic cells that attracts naïve T cellsB7 binds to B7 on P-APCsITAMS part of the co-stimulator of the T-cellphagocytosis of bacteria by macrophages leads to release of substances that induce B7 expression in macrophages(immunoreceptor tyrosine-based activation motifs)ZAP-70 sequences located on CD3 cytoplasmic tailsIL-2 associate with cytoplasmic tyrosine kinasesbinds to phosphorylated zeta chain ITAMs and is phosphorylated and activated by Lcksuper important cytokine for proliferation and differentiation of activated T cellsNFAT synthesized and secreted by activated T cellsbinds IL-2 receptors of T cell to drive clonal expansion of the activated cellactivation of NFAT activates transcription of the IL-2 geneFas ligand (FasL) binds to Fas receptor molecule on surface of target cellFas:FasL interaction --> signal to target cell to undergo apoptosisCD40 CD40 ligand on T cells interacts with CD40 receptor on macrophages/B cellsdelivers second signal for macrophage/B-cell activationITAMs on Igalpha and Igbeta chain of BCRBlk, Fyn, Lyn tyrosine kinases that phosphorylate ITAMsSyk binds to phosphorylated ITAMs of IGbeta tail (leads to transphosphorylation)CR2 part of B-cell co-receptor; binds to complement (C3d)CD19 part of B-cell co-receptor; receptor signaling chain; phosphorylated by tyrosine kinasesCD81 part of B-cell co-receptor; unknown functionCR1 on B-cell/macrophage surface; binds to C3b (on pathogen); cleaves to c3dLPS binds to CD14/TLR-4 to produce a co-activating signal (CD14+TLR-4+BCR+B-cell co-receptor activates B cells)CCL13 if B-cell doesn't meet antigen in LN, CCL13 draws it to the follicleIL-4 antigen specific CD4 T-cell helpers activated in presence of IL-4essential for B-cell proliferation and development to plasma cellstells centrocytes to become memory cells (infection has subsided)IL-5 B cells interact with TH2 to form primary focus of proliferating and activating B cells and Th2 cellsIL-6 B cells interact with TH2 to form primary focus of proliferating and activating B cells and Th2 cellsNFκB transcription factor on B cell; activated by CD40:CD40 ligand interaction; up-regulates ICAM-1 and cytoplasmICAM-1 binds to LFA-1 on T-cell; strengthened cognate interactions b/w B and T cellBcl-xL proteins when centrocytes bind to antigen in the light zone, engagement with T-cells induces centrocyte to express itprevents death by apoptosisTGFβ, IL-4, IL-5 prominent cytokines of TH2 cellsMAC membrane attack complexproduces