Clusters of Differentiation

CD11a

Found on lymphocytes, granulocytes, macrophages, monocytes. Alpha chain (w/ beta CD18) forming lymphocyte function-associated antigen I (LFA-1)

CD85

Isotypes A-M found on varying cells. D: involved in development of tolerance A-B: NK mediated cytotoxicity C/E: MHCI Ag soluble receptor

CD27

Found on lymphocytes and early BM progenitors. Receptor for tumor necrosis factor (TNF). Soluble form correlate with chronic inflammation. Role (w/ CD70) in activating NF-KB and MAPK8/JNK.

CD81

Found on lymphocytes, endothelial. a.k.a Target of antiproliferative antibody 1 (TAPA-1) Aids in recognition of complement by B cells. Close association with MHCs.

CD29

Found on leukocytes. a.k.a integrin beta 1 Subunit associated with late antigen receptors. Makes a3b1 complex that reacts to neural peptides.

CD53

Found on leukocytes. NOT platelets, RBCs, non-hematopoietic. Signal transduction related to development/growth/motility. Pan-leukocytic marker.

CD52

Found on lymphocytes (NOT plasma) monocytes, granulocytes. Carrying carbohydrates, esp. in male reproductive tract.

CD38

Found on lymphocytes and NK. A.k.a cyclic ADP ribose hydrolase Catalyzes synth/hydrolysis of cADP-ribose; essential for intracellular Ca(2+) regulation.

CD45

Found on leukocytes. Most commonly known as Protein Tyrosine Phosphatase, Receptor Type C (PTPRC) Regulates T/B cell antigen receptor signaling, costimulatory.

Graded Commitment Model

Each division on pathway has a probability of committed precursor for a cell type branching off, odds increase as move away from MPPs (multipotent progenitors)

CD67

Former designation of CD66b

CD14

Found in dendritic cells, macrophages, neutrophils, monocytes, B-cells. Pattern recognition receptor (PRR) that coreceptors with TLR-4 and MD-2 to detect LPS (especially S chirality). Also recognizes lipoteichoic acid. Soluble form (secrete by liver/monocytes) aids non-possessing cells in detection of LPS, inflammatory.

Ly6c

Found in hematopoietic cells Costimulates T-cell activation, acts with CD3-TCR complex, can induce IL2 production

CD37

Found in mature lymphocytes, granulocytes. Tetraspanin that may discourage phagocytosis of carrying cell by others? Signal transduction.

CD192

Found in monocytes a.k.a Chemokine receptor type 2 (CCR2) Receptor for CCL2 (monocyte chemoattractant protein-1) to mediate monocyte chemotaxis

CCR2

Found in monocytes Chemokine receptor type 2 a.k.a CD192 Receptor for CCL2 (monocyte chemoattractant protein-1) to mediate monocyte chemotaxis

CD36

Found in platelets, monocytes, macrophages, etc. Scavenger receptor of free fatty acids, collagen, phospholipids. Functions as a toll-like receptor (TR) for specific bacterial lipids.

CD40

Found on APCs, B lymphocytes. Binding of CD154 activates APCs. Activates resting B cells in the presence of TCR.

CD64

Found on APCs, activated DCs, macrophages, monocytes, early myeloid cells. a.k.a FcgammaRI Binds to IgG with high affinity, even monomeric, very important for RME Ag capture.

CD58

Found on APCs, esp. macrophage, and various other cells. a.k.a Lymphocyte function-associated antigen 3 (LFA-3) Cell adhesion molecule binding to CD2 on T cells. Strengthens adhesion while non-active T-cells are exploring for antigen to match the TCR.

CD79

Found on B cells and plasma cells. Both a and b isoforms are components of B-cell antigen receptor, in addition to surface Ig.

CD72

Found on B cells only (NOT plasma.) a.k.a Lyb-2 (mice); ligand for CD5/CD100 Stops naïve B cells from becoming plasma cells, regulate mature B cell differentiation.

CD77

Found on B cells, megakaryoblasts, platelets. Carbohydrate interacting with CD19 (B-cell coreceptor).

CD78

Found on B cells. Deleted?

CD74

Found on B, activated T, macrophage, interdigitating DCs, endothelial. a.k.a HLA class II histocompatibility antigen gamma chain ; invariant chain Protein for MHCII chaperoning and transport from ER to loading compartments.

CD84

Found on B, mature/memory T, thymocytes, monocytes, DCs, etc. a.k.a Signaling Lymphocytic Activation Molecule 5 (SLAM-5) Adhesion molecule, helps T cell proliferate and platelet aggregate.

CD43

Found on leukocytes (not resting B-cells). a.k.a leukosialin or sialophorin May be a PRR for mycobacterial protein homologs.

CD21

Found on B-cells and follicular DCs. More commonly called Complement Receptor 2 (CR2) or Epstein-Barr virus receptor. Binds Ag on B-cell membrane IgM through attached C3d complement, upping B-cell response. Regulates IgE production with CD23.

CD20

Found on B-cells only, increasingly from preB stage. Ca(2+) permeable cation channel, helps activate/grow B-cells.

CD73

Found on B/T subset, endothelial, follicular DCs, epithelial. Most commonly known as ecto-5'-nucleotidase Converts purine 5' mononucleotides to nucleosides (dephosphorylation). Costimulatory during T cell activate.

CD86

Found on DC subsets, memory B, monocytes, endothelial, etc. Negative stain for immature DCs. Costimulatory signal (like CD80) with CD28 or CD152 needed for T cell activation.

CD23

Found on IL4 stimulated myeloid lineage/B-cells. a.k.a Fc epsilon RII Soluble cleaved form weakly binds IgE, stops IgE synthesis (even IL4), suppresses B-cell growth (B-cell growth factor). Allows histamine release with IL3 in BM progenitors.

CD56

Found on NK (bright immunoregulatory), activated T cells, Schwannn, neural tissue. Most commonly known as neural cell adhesion molecule (NCAM) Adhesion and neurite outgrowth, plasticity.

CD35

Found on RBCs, leukocytes, follicular DCs, monocytes. More commonly known as Complement Receptor 1 (CR1). Main route of clearing opsonized immune complexes. Can negatively regulate complement, classic/alternative, and up phagocytosis. Also binds mannose-binding lectin (MBL.)

CD25

Found on T and B cells activated by Ag, and some myeloid precursors. a.k.a IL2Ralpha, T-cell growth factor receptor Alpha chain of IL-2 receptor.

CD60

Found on T subsets, platelets, monocytes and others. Carbohydrate (9-O-acetylated ganglioside D3).

CD87

Found on T, NK, monocytes, macrophages, basophils, etc. Most commonly known as Urokinase receptor. Part of the plasminogen activation system, helps restrict activation to cell membrane during proteolysis involved in wound tissue reorganization.

CD28

Found on T-cells (naïve and not.) Receptor for CD80 and CD86 of APCs. Costimulation leads to T-cell activation and when coupled with TCR, IL-6 production. A naïve T-cell that encounters MHCII without CD28 interaction becomes anergic.

CD10

Found on T/B cells (precursors), neutrophils, monocytes, BM, keratinocytes. Metallopeptidase cleaves many vasoactive/inflammatory peptides.

CD70

Found on activated B and T cells, monocyte derived DCs. a.k.a CD27 ligand Helps activate/proliferate T cells, especially CD8+. Helps activate NF-KB and MAPK8/JNK.

CD39

Found on activated B cells, T cell subsets, macrophages, DCs. A.k.a Ectonucleoside triphosphate diphosophohydrolase 1 (ENTPD1) Hydrolyzes ATP and ADP. Inhibits ADP-induced platelet aggregation. May aid in cellular infiltration.

CD80

Found on activated B, T, macrophage, and DCs. Provides (or CD86) the second (costimulatory) signal needed for T cell activation. Ligand for CD28 and CD152.

CD30

Found on activated B/T cells but NOT resting lymphocytes or monocytes. Lead to the activation of NF-KB (via TRAF2 and 5). Positive regulator of apoptosis-- limit self-reactive CD8.

CD69

Found on activated T, B, NK, neutrophil, eosinophil, platelets, etc. Earliest inducible glycoprotein in activation, may proliferate or signal transduction. Lectin.

CD26

Found on activated T/B cells and macrophages. Most commonly known as Dipeptidyl peptidase-4 Cleaves X-proline dipeptides off of N-terminus of polypeptides, diverse substrates (growth factors, chemokines.) May impair insulin sensitivity.

CD82

Found on activated hematopoietic cells, endothelial. Metastasis suppressor, correlated with p53.

CD47

Found on all circulating cells (in isotype 2). Receptor for thrombospondin-1 (TSP-1) of angiogenesis, migration, inhibits phagocytosis/stimulates cell-cell fusion/T-cell activation in SIRPa (+) cells.

CD32

Found on all immune cells and some epithelial. Removes IgG:Ag complexes from circulation, FcIgG receptor. Langerhans secrete soluble form to block other cells.

CD71

Found on all proliferating cells. a.k.a transferrin receptor Needed for iron transport into proliferating cells, IgA receptor on mesangial cells.

CD55

Found on any cell that contacts complement. Most commonly known as complement decay-accelerating factor (DAF) Interaction with C4b and C3b on other cells stops formation of C4b2a and C3bBb-- blocks formation of membrane attack complex (MAC.)

CD62

Found on different depending on isoform, L on leukocytes, E on activated endothelial, P on platelets. L, E, or P selectin. Aid in adhesion to inflammatory sites.

CD34

Found on early hematopoietic stem cells and a sub-population of DCs near skin. Murine mast cells. Cell-cell adhesion factor. Body cells express often for adherence.

CD18

Found on everything expressing CD11a, b, or c. Leukocytes. Beta subunit of CD11a, b, and c integrins.

CD19

Found on follicular DCs, and B-cells (not plasma cells). B-cell coreceptor (with CD21 and 81) utilized in signal transduction. Surface immunoglobulin (sIg)-associated molecule.

CD66b-d

Found on granulocytes. Cell adhesion molecule, activates neutrophils

CD24

Found on immature hematopoietic cells and neurons, usually lost upon final differentiation (exception RBCs) Glycoprotein may have a role in B-cell apoptosis.

CD54

Found on immune cells and endothelial. Most commonly known as intercellular adhesion molecule 1 (ICAM-1). Concentrations increase upon IL1 or TNF. Ligand for LFA-1: when activated transmigrate into tissues.

CD11a/CD18

Found on lymphocytes, macrophages, neutrophils. a.k.a. Lymphocyte Function-associated Antigen I (LFA-1) Weak initial adherence to APC's ICAM-1 becomes stronger w/ T-cell/cytokine receptor activity. Import for T-cell/T-cell interactions.

CD48

Found on lymphocytes, macrophages, some DCs. Inflammatory monocytes turning into DCs low in. a.k.a B-lymphocyte activation marker (BLAST) Aids APC contact with T-cell via coupling with CD2. Form lipid rafts.

CD50

Found on lymphocytes, monocytes, granulocytes, Langerhans, etc. Most commonly known as intercellular adhesion molecule 3 (ICAM-3) Adhesion, powerful ligand for lymphocyte-function associated Ag 1 (LFA-1), signalling

CD68

Found on macrophage, monocytes, DCs, myeloid cells, neutrophils, etc. a.k.a macrosialin (mice) Specific to lysosomes, may have role in macrophage phagocytosis, allow homing, binds LDL.

CD59

Found on many cells, RBCs, blood leukocytes. a.k.a Membrane attack complex-inhibitory protein (MAC-IP) or protectin Can stop C9 polymerization when C5b678 deposited on host cell. Still sensitive to perforin (lymphocytes).

CD44

Found on many cells. Certain isoforms on hematopoietic. Involved in cell adhesion, receptor for hyaluronic acid, lymph node homing.

CD75

Found on mature B cells, RBCs, some T/epithelial. Carbohydrate ligand for CD22 (help regulate MHCII and IgM).

CD76

Found on mature B cells, RBCs, some T/epithelial. Carbohydrate ligand for CD22 (help regulate MHCII and IgM). (Like CD75).

CD22

Found on mature B cells, usually activated ones. Lectin that binds alpha-2,6-linked sialic acids (on T and B cells, see CD45). Regulates MHCII and IgM expression.

CD83

Found on mature DCs and some proliferating lymphocytes (human). May aid in presentation or following interactions with lymphocytes. May DC maturation, DC-mediated T cell proliferation.

CD12

Found on monocytes, granulocytes, NK, platelets. NOT found on basophiles, BM precursors.

CD13

Found on monocytes, granulocytes, T-cells, some body cells. a.k.a. Aminopeptidase N Metalloprotease that cleaves N-terminus AAs off of peptides, degrades some neuropeptides

CD11b

Found on monocytes, macrophages, granulocytes, and NK integrin alpha M glycoprotein; alpha subunit of MAC-1 mediate inflammatory adhesion/migraton and complement uptake

CD16

Found on monocytes, neutrophils, macrophages, and NK, other immune cells. Fc (fragment crystallizable, "constant") -IgG receptor subtype, associated with protein tyr kinase (PTK) Ick. May be secreted soluble.

CD15

Found on murine pluripotent stem cells, promyelocytes, neutrophils, monocytes, eosinophils and activated T-cells. a.k.a 3-fucosyl-N-acetyl-lactosamine Carbohydrate adhesion molecule (CAM) expressed on glycoproteins including CD11b.

CD11c

Found on myeloid dendritic cells (also monocytes, macrophages, few neutro and B) integrin alpha X glycoprotein activates cells and triggers neutrophil respiratory burst

CD33

Found on myeloid lineage cells and NKs. Marker for early BM hematopoietic stem cells. a.k.a sialic acid binding Ig-like lectin 3 (SIGLEC-3) Binds certain mucins and sialyl-Tn. Can prevent DC formation in monocytes and CD34+ myeloid.

CD65

Found on myeloid lineage cells and monocytes. a.k.a VIM-2, ceramide-dodecasaccharide Adhesive carbohydrate.

CD57

Found on natural killer cells, B/T subsets, monocytes. Most commonly known as B3GAT1 or human natural killer-1 (HNK1). Carbohydrate epitope found in many neural adhesion molecules. May contribute to T-cell activating B.

CD46

Found on nucleated cells (not RBC) in humans, testicular germ cells of mice. Regulation of complement, cofactor for C3b and C4b inactivation by serum factor I.

CD42

Found on platelets and megakaryocytes (late). Allows for platelet adhesion especially to vascular injury.

CD41

Found on platelets and megakaryocytes. Most commonly known as Integrin alpha-IIb (ITGA2B). Part of a fibrinogen receptor that is important in coagulation.

CD51

Found on platelets, megakaryocytes, macrophages, endothelial. The integrin alpha V component of vitronectin receptor. Phagocytosis receptor on macrophages.

CD31

Found on platelets, monocytes, granulocytes, endothelial and B cells. a.k.a Platelet endothelial cell adhesion molecule (PECAM-1) EndoCAM (endothelial cellular adhesion molecule) Involved in leukocyte migration and removal of old granulocytes.

CD63

Found on platelets, monocytes, macrophages. a.k.a lysosomal-associated membrane protein 3 (LAMP-3) Associates with integrins and may mediate their signaling/activate platelet spreading.

CD7

Found on pluripotential (T, B, myeloid) hematopoietic cells, thymocytes, T-cells, NKs. May be linked to lymphopoesis potential.

CD9

Found on pre-B cells, platelets, eosinophils and basophils. Signal transduction and coagulation via exosomes, repression of metastasis, critical for egg/sperm fusion.

CD8

Found on some dendritic cells (especially CD4- splenic), thymocytes, T-cells, NKs. Dimeric T-cell coreceptor; found on cytotoxic T-cells, adhesion molecule for MHC I.

CD4

Found on some dendritic cells (especially CD8- splenic), monocytes, macrophages. Found on MHCII restricted T-cells. Stabilizes interaction between MHCII presenting APC and T-cell. Intracellular signal transduction (associate with Tyr Kinase Ick)

MAC-3

Found on some myeloid cells, macrophages (lysosome/plasma memb) a.k.a CD107b or LAMP-2 Type 1 membrane glycoprotein; ligand for galaptin (S-type lectin in extracellular matrix)

CD107b

Found on some myeloid cells, macrophages (lysosome/plasma memb) a.k.a MAC-3 or LAMP-2 Type 1 membrane glycoprotein; ligand for galaptin (S-type lectin in extracellular matrix

CD61

Found on thrombocytes, some B cells, myeloid progenitors, etc. a.k.a integrin beta 3 chain (ITGB3) Combines with CD41 or CD51 to form receptors for fibrinogen, thrombospondin, etc.

CD3

Found on thymocytes and T-cells T-cell coreceptor, complex composed of many transmembrane chains

CD6

Found on thymocytes and T-cells. Aids in interaction of T-cells with non-professional APCs, signaling attenuator for T-cells. Upregulated upon IFN-gamma.

CD5

Found on thymocytes, T-cells, B-cell subsets (IgM secreting B-1 cells) dampens self-reaction. Upregulated upon T-cell activation.

CD2

Found on thymocytes,T-cells and NKs Cell adhesion molecule (adheres to CD48) and co-stimulatory to T and NK

CD17

Found on tonsil DCs, monocytes, granulocytes, macrophages, CD19+ B-cells. a.k.a Lactosylceramide Not a protein

CD1a-c

Glycoprotein family found in antigen presenting cells (APCs); CD1d found on wider variety Present lipid antigens to T-cells

Integrin

Heterodimer integral protein family with alpha and beta chain

CD49

Integrin alpha subunits (a-f). b: Very late antigen (VLA) of platelets, activated lymphocytes. c: VLA of non-hematopoietic BM e: part of fibronectin receptor

Thymocytes

May be both CD4 and CD8 positive, single, or negative during development. Hematopoietic cells of thymus that develop into T-cells.

GM-CSF

Protein secreted by macrophages, T-cells, NK, endothelial/fibroblasts, mast cells. Granulocyte Macrophage Colony Stimulating Factor aka Colony Stimulating Factor 2 (CSF2) Directs granulocyte and monocyte generation, inflammatory cascade

Tip

Tumor necrosis factor-alpha, Inducible nitric oxide synthase Producing dendritic cells. CD11c int; CD11b hi; MAC-3 (+) Derived from Ly6c hi monocytes via CCR2, during inflammation