Week 1 Flashcards
CXCL13
produced by BRCs in the LN; essential for proper B cell migration and compartmentalization into follicles
CCL21
produced by TRCs in the LN, essential for T cell migration into and compartmentalization of T cells in the LN
Cathespin B
Also known as Cath-B. Converts immobile CXCL13 to soluble CXCL13, allowing for proper B cell localization in the LN.
CCR7
Receptor for CCL21/19. Mostly expressed on T cells and DCs and used to co-localize these cells in the T-zone in LN to facilitate their interaction.
TRC produces these cytokines:
CCL19, CCL21, CXCL12, and IL-7.
CCL19
Specific for CCR7 and produced by TRCs in LNs. Attracts T cells to the LNs.
LPA/LPA2
LPA binds receptor LPA2 on T cells, which both activates RhoA and reduces T cell adhesion to the reticular network, driving T cell migration [23]. Accordingly, both FRC-specific LPA and T cell specific LPA2 knockout mice exhibit strongly reduced T cell migration within the T zone
IL-7
T cell survival cytokine produced by stromal cells in the LNs and thymus.
PDPN
Podoplanin, expressed on stromal cells, regulates actomyosin properties of FRCs in LNs, thereby dictating LN stiffness/shape.
Also interacts with CLEC2 expressed on DCs, to facilitate DC mobility in T cell zone.
CXCL13
ligand for CXCR5, expressed by naive B cells. CXCL13 is produced by fDCs in the B cell follicle to recruit naive B cells.
CXCR5
Receptor for CXCL13. Expressed by naive B cells, allowing them to home to the B cell follicle in the LN.
LFA-1
Leukocyte Factor 1: Integrin composed of CD11a/CD18
CD18
Beta chain of B2 integrins (LFA-1, etc.)
CD64
Fc(gamma)RI, expressed on Mqs, monocytes
α4β7
Binds MAdCAM-1 expressed on gut vascular endothelium; allows for homing to the lamina propia
CCR9
Receptor for CCL25, which is expressed in the small intestine.
CCL25
Ligand for CCR9. Expressed in the small intestine.
CD103
Expressed on some LP cDCs (also known as integrin αE)
Three different types of LP cDCs (based on markers)
CD103+CD11b−XCR1+cDC1 (XCR1+ cDC1)
CD103+CD11b+SIRPα+cDC2 (CD103+ cDC2)
CD103−CD11b+SIRPα+cDC2 (CD103− cDC2)
Zbtb46
Transcription factor required for development of all three subtypes of LP cDCs.
XCR1+ cDC1 transcription factor requirements
BATF3, Id2, or IRF8
CD103+ cDC2 transcription factor requirements
IRF4, Notch2, or KLF4
CD103− cDC2 transcription factor requirements
Zeb2
intestinal macrophage markers
CD64, F4/80, Mer tyrosine kinase, CD169 (and most are CX3CR1+)
Th17 cytokines
IL-17 A, IL-17 F, IL-21, and IL-22
“find-me” signals released by dying cells to stimulate nearby phagocytes
modified membrane lipids (LPC, S1P), nucleotides (ATP, UTP), chemokines (CX3CL1).`
DNaseI v. DNaseII v. DNaseIII
DNaseI degrades DNA in the EC environment, while DNaseIII degrades cytoplasmic DNA. DNaseII degrades DNA in the lysosomes of phagocytes that have engulfed dying cells.
phosphatidylserine
phospholipid restricted to the inner leaflet of the plasma membrane in healthy cells. It becomes exposed on the outer leaflet during apoptosis and is recognized by scavenging phagocytes for engulfment of the presenting cell.
CD36
Scavenger receptor that recognizes anionic phospholipids exposed on dying cells; promotes engulfment of those cells.
Dynamin
A member of the protein gTPase family, mainly involved in the scission of newly formed vesicles from a membrane and their fusion with another membrane.
Microtubule-associated protein 1A/1B light chain 3 (LC3)-associated phagocytosis (LAP)
A non-apoptotic function of several proteins of the autophagy pathway, resulting in lipidation of lC3 family proteins on the phagosome membrane, enhancing fusion
of the phagosome with lysosomes.
Pannexin 1 (PANX1)
Caspase3/7-activated channel protein that forms a small pore in the plasma membrane of cells undergoing active apoptosis, allowing small (<1kDa) proteins such as ATP to escape into the EC matrix as ‘find-me’ signals for phagocytes.
Liver X Receptors (LXRs) and peroxisome proliferator-activated receptor (PPARs)
nuclear receptor transcription factors that dimerize with retinoid X receptors (RXRs) in response to ligands (e.g., oxysterols by LXRs, unsaturated fatty acids by PPARs) to regulate lipid metabolism gene transcription - importantly activated upon ingestion of an apoptotic cell by a phagocyte to correct for the massive influx of lipid upon degrading a cell.
Dectin-1
strongly expressed by macrophages, neutrophils and DCs and recognizes -1,3-linked glucans (polymers of glucose), which are common components of fungal cell walls
mannose receptor (MR)
C-type lectin expressed by macrophages and DCs that recognizes various mannosylated ligands present on bacteria and fungi, and assists in scavenging in Mqs
Class A scavenger receptors
SR-A I, SR-A II, and MARCO (macrophage receptor with a collagenous structure), which all bind various bacterial cell-wall components and help to internalize bacteria
fMet-Leu-Phe (fMLF) receptor
G-protein-coupled receptor that senses the presence of bacteria by recognizing a unique feature of bacterial polypeptides. Protein synthesis in bacteria is typically initiated with an N-formylmethionine (fMet) residue, an amino acid present in prokaryotes but not in eukaryotes
NADPH oxidase
Also known as phagocyte oxidase, it is a membrane-associated multicomponent enzyme that generates superoxides in activated phagocytes.
chronic granulomatous disease (CGD)
Disease in which patients with a deficiency in NADPH oxidase present with an inability to produce toxic oxygen derivatives and a decreased ability to kill ingested microbes
TLR1:TLR2 heterodimer ligands
Lipomannans (mycobacteria)
Lipoproteins (diacyl lipopeptides; triacyl lipopeptides) Lipoteichoic acids (Gram-positive bacteria)
Cell-wall β-glucans (bacteria and fungi)
Zymosan (fungi)
TLR1:TLR2 heterodimer hematopoietic expression
Monocytes, dendritic cells, mast cells, eosinophils, basophils
TLR-2:TLR-6 heterodimer ligands
Lipomannans (mycobacteria)
Lipoproteins (diacyl lipopeptides; triacyl lipopeptides) Lipoteichoic acids (Gram-positive bacteria)
Cell-wall β-glucans (bacteria and fungi)
Zymosan (fungi)
TLR-2:TLR-6 heterodimer hematopoietic expression
Monocytes, dendritic cells, mast cells, eosinophils, basophils
TLR-3 ligands
Double-stranded RNA (viruses), poly I:C
TLR-3 hematopoietic expression
Macrophages, dendritic cells, intestinal epithelium
TLR-4 ‘co-receptors’
MD-2 and CD14
TLR-4 &co. ligands
LPS (Gram-negative bacteria) Lipoteichoic acids (Gram-positive bacteria)
TLR-4 & co. hematopoietic expression
Macrophages, dendritic cells, mast cells, eosinophils
TLR-5 ligands
Flagellin (bacteria)
TLR-5 hematopoietic expression
Intestinal epithelium, macrophages, dendritic cell
TLR-7 ligands
Single-stranded RNA (viruses)
TLR-7 hematopoietic expression
Mostly Plasmacytoid dendritic cells,, B cells
TLR-8 ligands
Single-stranded RNA (viruses)
TLR-8 hematopoietic expression
Macrophages, neutrophils
TLR-9 ligands
DNA with unmethylated CpG (bacteria and herpesviruses)
TLR-9 hematopoietic expression
Plasmacytoid dendritic cells, eosinophils, B cells, basophils
TLR-10 ligands
(human only) Unknown!
TLR-10 hematopoietic expression
Plasmacytoid dendritic cells, eosinophils, B cells, basophils
TLR-11 ligands
(mouse only) - profilin and profilin-like proteins (Toxoplasma gondii, uropathogenic bacteria)
TLR-11 hematopoietic expression
(mouse only) - Macrophages, DCs (also liver, kidney and bladder)
TLR-12 ligands
(mouse only) - profilin (Toxoplasma gondii)
TLR-12 hematopoietic expression
(mouse only) - Macrophages, DCs, (also liver kidney and bladder)
TLR-13 ligands
(mouse only) - ssRNA (bacterial ribosomal RNA)
TLR-13 hematopoietic expression
(mouse only) - Macrophages, DCs
Extracellular TLRs (plasma membrane bound)
TLR2:TLR1 heterodimers, TLR-2:TLR-6 heterodimers, TLR-5, TLR-4
Intracellular TLRs (vesicle/endosome bound)
TLR-3, TLR-7, TLR-8, TLR-9
MD-2
Accessory protein for TLR-4 signaling that binds to TLR-4 within the cell and is necessary for proper trafficking of the PRR.
Four signaling molecules used in TLR signaling
MyD88, MAL (TIRAP), TRIF, TRAM
TLR-2 and TLR-1 adaptor molecule
MyD88/MAL (TIRAP)
TLR-3 adaptor molecule
TRIF
TLR-4 adaptor molecules
MyD88/MAL (TIRAP), TRIF/TRAM
TLR-5 adaptor molecule
MyD88
TLR-2/6 adaptor molecule
MyD88/MAL (TIRAP)
TLR-7 adaptor molecule
MyD88
TLR-8 adaptor molecule
MyD88
TLR-9 adaptor molecule
MyD88
TLR-11/12 adaptor molecule
MyD88
TLR-13 adaptor molecule
MyD88
NFkB transcription effects
proinflammatory cytokines such as TNF-a, IL-1B and IL-6.
NOD1 ligand
D-glutamyl meso-diaminopimelic acid (iE-DAP), a breakdown product of peptidoglycans of Gram-negative bacteria such as Salmonella and some Gram-positive bacteria such as Listeria
NOD2 ligand
muramyl dipeptide (MDP), which is present in the peptidoglycans of most bacteria
TIR domain proteins
MyD88, MAL, TRIF, TRAM, all TLRs
CARD domain proteins
Caspase 1, RIP2, RIG-1, MDA-5, MAVs, NODs,NLRC4,ASC, NLRP1
Pyrin domain proteins
AIM2, IFI16, ASC, NLRP1-14
DD (death domain) domain proteins
MyD88, IRAK1, IRAK4, DR4, DR5, FADD, FAS
DED (death effector domain) domain proteins
Caspase 8, caspase 10, FADD