| 1989 |
CD13 (gp150) is identical to aminopeptidase N: it is an integral membrane protein with a single 24 amino acid N-terminal hydrophobic segment that serves as both signal for membrane insertion and stable membrane-spanning anchor, with the remainder forming a large extracellular C-terminal domain containing the zinc-binding metalloprotease pentapeptide consensus sequence. |
cDNA cloning, retroviral expression in mouse fibroblasts, amino-terminal protein sequence analysis |
The Journal of clinical investigation |
High |
2564851
|
| 1986 |
The human myeloid membrane antigen gp150 gene was molecularly cloned, shown to encode a 4.0-kb polyadenylated transcript, mapped to chromosome 15q25-26, and shown to be biologically active when transfected into NIH 3T3 cells; gp130 was identified as a carbohydrate-differing precursor to the mature cell-surface gp150. |
Bacteriophage lambda library cloning, DNA transfection, in situ hybridization, pulse-chase metabolic labeling, biochemical analysis |
The Journal of clinical investigation |
High |
2428842
|
| 2001 |
CD13/APN is functionally essential for capillary tube (lumen) formation during angiogenesis; functional antagonists of CD13/APN block tube formation but not proliferation of primary vascular endothelial cells, and CD13/APN expression is transcriptionally upregulated by hypoxia and angiogenic growth factors via elements in the proximal promoter. |
In vitro tube formation assay with CD13 antagonists, reporter assays with CD13 proximal promoter, in vivo models (retinal neovascularization, chorioallantoic membrane angiogenesis, xenograft tumor growth) |
Blood |
High |
11157481
|
| 2007 |
CD13 controls endothelial cell invasion and filopodia formation by facilitating bradykinin B2 receptor (B2R) internalization and downstream Cdc42 activation at the plasma membrane; CD13 inhibition blocks B2R internalization, abrogating invasion and filopodia; wild-type but not catalytically inactive mutant CD13 restores membrane protein organization, indicating peptidase activity is required for CD13's regulatory function. |
B2R internalization assay, Cdc42 activation assay, filopodia imaging, cholesterol depletion/repletion experiments, expression of wild-type vs. enzymatic mutant CD13 |
Blood |
High |
17363739
|
| 1998 |
The CD13/APN promoter is transcriptionally activated by the DMP1 transcription factor binding to a specific consensus site; DMP1 activation of CD13 requires intact DNA-binding and transactivation domains of DMP1 and is antagonized by D-type cyclins in a CDK-independent manner; CD13 expression is additionally co-regulated by cooperative interaction between c-Myb and Ets-1. |
Promoter reporter assays, electrophoretic mobility shift assay (EMSA), dominant-negative and deletion mutant analyses of DMP1 and cyclin constructs |
The Journal of biological chemistry |
High |
9786929
|
| 2001 |
An N-glycosylation site at amino acids 288–295 of human APN is a critical molecular determinant of species-specific coronavirus receptor activity: introduction of an N-glycosylation sequon at position 291–293 abolished HCoV-229E receptor activity of hAPN, while single-amino-acid revertants removing this sequon fully restored binding and receptor activity. |
Site-directed mutagenesis of hAPN, virus binding and infection assays in transfected cells |
Journal of virology |
High |
11559807
|
| 1998 |
Human APN (CD13) serves as the functional cellular receptor for human coronavirus 229E (HCoV-229E) in neural cells: hAPN is expressed on neuronal and glial cell line surfaces, anti-hAPN monoclonal antibody WM15 inhibits radiolabeled HCoV-229E attachment and infection, and attachment level correlates with hAPN surface amount. |
Flow cytometry for receptor expression, radiolabeled virus attachment assay, antibody blocking, indirect immunofluorescence infection assay |
Journal of virology |
High |
9658094
|
| 2013 |
CD13 cross-linking induces phosphorylation of Src, FAK, and ERK, and CD13 itself is phosphorylated on its cytoplasmic tyrosine in a Src-dependent manner; CD13 is constitutively associated with the scaffolding protein IQGAP1, and cross-linking induces complex formation with α-actinin, linking CD13 to the cytoskeleton; mutation of the conserved cytoplasmic tyrosine to phenylalanine abolishes adhesion, downstream signaling, and cytoskeletal changes; phospho-CD13 is present in vivo in peritoneal exudate cells, and monocytes expressing the mutant CD13 show severely impaired migration into the inflamed peritoneum. |
Phosphoprotein analysis, Src/FAK/ERK inhibition assays, site-directed mutagenesis (Y→F), co-immunoprecipitation with IQGAP1 and α-actinin, adoptive transfer in murine peritonitis model |
Journal of immunology |
High |
23997214
|
| 2008 |
CD13 ligation and clustering by mAb or viral ligands induces myeloid/endothelial cell adhesion via signal transduction-dependent monocytic cytoskeletal rearrangement and filopodia formation; soluble recombinant CD13 blocks this adhesion; CD13 molecules from monocytic and endothelial cells co-immunoprecipitate, indicating direct homotypic CD13–CD13 interaction; anti-CD13 antibodies reduce leukocyte infiltration in murine peritonitis. |
Antibody-mediated cross-linking adhesion assays, recombinant CD13 blocking, co-immunoprecipitation, adhesion to immobilized recombinant CD13, murine peritonitis model |
Journal of leukocyte biology |
High |
18495788
|
| 2015 |
CD13 negatively regulates TLR4 endocytic signaling: CD13 is co-internalized with TLR4, CD14, and dynamin into Rab5+ early endosomes upon LPS stimulation; CD13 KO dendritic cells show enhanced p-IRF-3 activation and transcription of IRF-3 target genes in response to TLR4 ligands while TLR4 surface signaling is unaffected; CD13 KO mice show enhanced IFNβ-mediated JAK-STAT signaling, elevated iNOS, and increased oxidative stress and tissue injury upon ischemia; CD13 and TLR4 co-immunoprecipitate in activated macrophages. |
CD13 KO mice, co-immunoprecipitation, IRF-3 phosphorylation assays, endosomal co-localization imaging, in vivo ischemia model, flow cytometry |
Journal of immunology |
High |
25801433
|
| 2012 |
CD13 negatively regulates receptor-mediated, dynamin-dependent endocytosis of antigens (OVA, transferrin) in dendritic cells but not fluid-phase or phagocytic uptake; CD13 is co-internalized with antigen but does not co-immunoprecipitate with antigen receptors; CD13 KO DCs show dysregulated phosphorylation of p38MAPK and Akt; lack of CD13 significantly enhances T cell responses to soluble OVA antigen in vivo. |
CD13 KO mice, in vitro antigen uptake assays, co-immunoprecipitation (negative), kinase inhibition, in vivo T cell response assays |
Journal of immunology |
High |
22544935
|
| 2006 |
CD13 antibody-mediated ligation induces apoptosis in AML cells independently of its APN enzymatic activity: anti-CD13 mAbs (MY7, SJ1D1, WM15) cause sub-G1 accumulation, DNA fragmentation, phosphatidylserine externalization, mitochondrial depolarization, Bcl-2/Mcl-1 downregulation, Bax upregulation, and activation of caspase-9, caspase-8, and caspase-3; enzymatic inhibitors of APN alone are ineffective; internalization of CD13–mAb complex precedes mitochondrial events. |
Flow cytometry (cell cycle, apoptosis markers), Western blotting (Bcl-2, Bax, caspases), caspase inhibitor experiments, comparison of enzyme-blocking vs. non-blocking antibodies |
FASEB journal |
High |
21566207
|
| 2005 |
CD13 associates with tumor-associated antigen L6 (TAL6) in a co-immunoprecipitable complex on lung cancer cells; CD13 enhances cancer cell migration and invasion; expression of enzymatically inactive CD13 mutant also significantly enhances cell migration, indicating that CD13's effect on motility does not strictly depend on its peptidase activity. |
Co-immunoprecipitation, antibody-mediated co-patching immunofluorescence, Transwell migration/invasion assays, enzymatic inhibitors, catalytically inactive CD13 mutant expression |
International journal of cancer |
High |
15812828
|
| 2006 |
CD13 mediates homotypic aggregation (HA) of monocytic cells via antibody cross-linking in a tyrosine kinase- and MAP kinase-dependent manner, independently of integrin signaling and independently of CD13 enzymatic activity; during HA, CD13 actively redistributes to cell–cell contact zones as observed by live cell imaging. |
Homotypic aggregation assays, enzyme inhibitor controls vs. kinase inhibitors, live cell imaging, colchicine/cytoskeletal perturbation |
Journal of leukocyte biology |
Medium |
16415167
|
| 2005 |
CD13/APN functionally interacts with FcγRI on monocytes: during FcγR-mediated phagocytosis, CD13 redistributes to the phagocytic cup and is co-internalized into phagosomes; co-cross-linking of CD13 with FcγRI increases the level and duration of Syk phosphorylation; FcγRI and CD13 co-localize in zones of cellular polarization. |
Confocal microscopy of phagocytosis, Syk phosphorylation assays, co-cross-linking with specific mAbs, co-localization imaging |
Journal of leukocyte biology |
Medium |
15758076
|
| 1995 |
Purified and native membrane-bound CD13/APN sequentially and completely hydrolyzes Leu-enkephalin and Met-enkephalin from the amino terminus; substance P and bradykinin are natural inhibitors of CD13/APN (Ki = 0.44 µM and 9.4 µM, respectively) due to their N-terminal proline at the second residue, which prevents hydrolysis. |
In vitro enzymatic assay with purified pig APN and live HL60 cells, Km and Ki measurements with natural peptide substrates and inhibitors |
Biochemical and biophysical research communications |
High |
7535053
|
| 1993 |
Cell-surface aminopeptidase N/CD13 is involved in tumor cell invasion through degradation of type-IV collagen: anti-CD13 mAb WM15 inhibits both aminopeptidase activity and type-IV collagen degradation by tumor cells, and reduces invasion through Matrigel in a concentration-dependent manner without affecting adhesion or migration. |
Matrigel invasion assay, type-IV collagen degradation assay, aminopeptidase activity assay with specific mAb inhibition |
International journal of cancer |
Medium |
8097496
|
| 2009 |
Porcine APN receptor density directly determines PEDV infection efficiency: overexpression of recombinant pAPN in ST cells rescues productive PEDV infection; the enzymatic active motif-null mutant pAPN retains receptor activity and supports viral production; APN inhibitor blocking the protease active site has no effect on viral infection, showing enzymatic activity is dispensable for PEDV receptor function. |
Stable cell line overexpression, enzymatic active-site mutant APN expression, aminopeptidase inhibitor treatment, viral infection/replication assays |
Veterinary microbiology |
High |
20074871
|
| 2019 |
APN (ANPEP) is a receptor for porcine deltacoronavirus (PDCoV) in porcine alveolar macrophages (PAMs): ANPEP knockout pigs generated by CRISPR/Cas9 show PAM resistance to PDCoV infection, but lung-derived fibroblast-like cells from the same KO pigs remain fully permissive, indicating APN is necessary in macrophages but dispensable in fibroblast cells for PDCoV infection. |
CRISPR/Cas9 ANPEP knockout pigs, viral infection of primary cell types, ex vivo and in vivo PDCoV challenge |
Virology |
High |
32056711
|
| 2020 |
CD13 interacts with HDAC5 to promote its protein stability; stabilized HDAC5 deacetylates LSD1 to stabilize it; LSD1 then decreases NF-κB p65 methylation, leading to p65 protein stability and NF-κB pathway activation; this CD13–HDAC5–LSD1–NF-κB axis promotes HCC proliferation, invasion, and sorafenib resistance. |
Co-immunoprecipitation, LC-MS/MS, Western blotting, xenograft models, patient-derived xenograft models |
Clinical and translational medicine |
Medium |
33377659
|
| 2020 |
CD13 overexpression activates the P38/Hsp27/CREB signaling pathway; CREB binds the ATG7 promoter to induce autophagy; this CD13-driven autophagy promotes HCC chemoresistance; CD13 inhibition downregulates ATG7, autophagy, and tumor growth in vivo. |
Western blotting, CREB-ATG7 promoter binding assay, autophagy assays, in vivo xenograft models with CD13 inhibitor |
The Journal of pharmacology and experimental therapeutics |
Medium |
32571958
|
| 2014 |
CD13 regulates mesenchymal stem cell (MSC) adhesion and migration via FAK activation: CD13 KO MSCs show impaired adhesion and migration on extracellular matrices, decreased phospho-FAK levels, and cytoskeletal alterations; CD13 antibody cross-linking of human MSCs increases adhesion to endothelial monolayers and induces FAK activation; CD13 KO MSCs show significantly poorer tissue repair in ischemic limb injury with reduced vascularization. |
CD13 KO mice, cell adhesion/migration assays, FAK phosphorylation assay, antibody cross-linking, in vivo ischemic limb model with cell injection |
Frontiers in physiology |
High |
24409152
|
| 2014 |
CD13 is required for muscle satellite stem cell anchorage and differentiation timing: CD13 KO muscle shows markedly reduced satellite cell numbers, impaired satellite cell adhesion, and accelerated differentiation; CD13 co-localizes with Pax7 on satellite cells; phospho-FAK and ERK levels are reduced in injured CD13 KO muscle. |
CD13 KO mice, satellite cell isolation and characterization, adhesion assays, differentiation assays, immunofluorescence co-localization, Western blotting for FAK/ERK |
Stem cells |
Medium |
24307555
|
| 2015 |
CD13 is a primary phagocytic receptor in human macrophages and monocytic cells: hCD13 expression alone in non-phagocytic HEK293 cells is sufficient to enable internalization of large particles bound through CD13; CD13-mediated phagocytosis is independent of FcγRs, CR3, and most phagocytic receptors, independent of CD13 enzymatic activity, but requires actin rearrangement, PI3K activation, and partial Syk activation; CD13 cross-linking induces pSyk and ROS production. |
Phagocytosis assays with receptor-specific opsonization, CD13 expression in non-phagocytic HEK293 cells, pharmacological inhibitors of PI3K and Syk, actin disruption, ROS measurement |
Journal of leukocyte biology |
High |
25934926
|
| 2014 |
CD13-dependent monocyte/endothelial adhesion is mediated by the C-terminal domain of CD13; lack of either monocytic or endothelial CD13 reduces myeloid cell trafficking into sites of inflammation in vivo; CD13 expression is enriched on pro-inflammatory monocyte subsets. |
Adoptive transfer of WT and CD13 KO myeloid cells into thioglycollate-challenged mice, chimeric CD13 (mouse/human) constructs identifying C-terminal domain requirement, flow cytometry of monocyte subsets |
Immunology |
Medium |
24627994
|
| 2000 |
CD13/APN enzymatic activity is responsible for its chemoattractant function for CD4+ T lymphocytes: soluble CD13/APN induces chemotactic migration of lymphocytes (more so for CD4+ than CD8+ T cells), and the aminopeptidase inhibitor bestatin abolishes this chemotactic activity. |
In vitro chemotaxis assay, bestatin inhibition of APN activity, BALF chemotaxis assay from sarcoidosis patients |
American journal of respiratory and critical care medicine |
Medium |
10806168
|
| 2006 |
Cell-surface CD13/APN regulates TNFα-induced neutrophil apoptosis by controlling shedding of TNFRI: APN inhibition (actinonin, bestatin) augments TNFα-induced killing and prevents TNFRI shedding, resulting in enhanced TNFα signaling; an inverse correlation exists between neutrophil APN activity and sensitivity to TNFα-induced apoptosis. |
Neutrophil apoptosis assays, TNFRI shedding measurement, APN activity measurement, pharmacological APN inhibitors |
The Journal of biological chemistry |
Medium |
16533817
|
| 2002 |
High cell-surface CD13/aminopeptidase N activity enables leukemic cells to resist endothelial IL-8-induced apoptosis; K562 cells transfected with CD13 acquire resistance to IL-8-induced apoptosis; aminopeptidase inhibitor bestatin restores IL-8-induced apoptosis in CD13-overexpressing cells and increases endothelial IL-8 secretion. |
CD13 transfection into K562 cells, apoptosis assays, aminopeptidase inhibitor bestatin treatment, co-culture with endothelial cells, IL-8 ELISA |
Journal of the National Cancer Institute |
Medium |
12096087
|
| 2021 |
CD13 localizes to the apical membrane and associates with Par6 as part of an apical polarity complex; CD13 is required to couple apical protein cargo to Rab11-endosomes and for capture of endosomes at the apical initiation site during epithelial lumen formation; this polarity function utilizes the short intracellular domain of CD13 but is independent of peptidase activity. |
CD13 KO cell lines, live imaging, co-immunoprecipitation with Par6, Rab11-endosome colocalization assay, domain deletion/mutation constructs, 3D lumen formation assay |
Nature communications |
High |
34349123
|
| 1993 |
CD13/aminopeptidase N activity is present in soluble form in cell-free plasma and represents the predominant quantitative aminopeptidase N activity in flowing blood; immunoaffinity-isolated plasma CD13 has similar electrophoretic characteristics to cell-derived material; lymphocyte-associated aminopeptidase N-like activity is not inhibitable by anti-CD13 antibodies, suggesting a distinct non-CD13 enzyme. |
Aminopeptidase N functional assay with chromogenic substrates, anti-CD13 mAb inhibition, immunoaffinity purification from plasma, SDS-PAGE, cell fractionation |
Experimental hematology |
Medium |
7902291
|
| 2010 |
In a CD13 null mouse, lack of CD13 completely ablates anti-CD13-dependent monocyte adhesion to wild-type endothelial cells, but CD13 is dispensable for normal hematopoietic development, proliferation, phagocytosis, and antigen presentation; a slight decrease in actin-independent erythrocyte uptake was observed in CD13 KO cells. |
CD13 null mouse generation, hematopoietic profiling, monocyte adhesion assay, in vitro phagocytosis and antigen presentation assays, inflammatory disease models |
Journal of leukocyte biology |
High |
20430777
|
| 2023 |
CD13 facilitates acute post-stroke monocyte and neutrophil transmigration into the brain; CD13 KO mice show reduced acute infarct volume; however, loss of CD13 impairs chronic post-stroke angiogenesis and recovery, associated with reduced CXCL12/CXCR4 signaling and reduced CD13+/lectin+ blood vessels at day 15 post-stroke. |
CD13 KO mice, MCAO stroke model, flow cytometry of infiltrating myeloid cells, CXCL12/CXCR4 quantification, angiogenesis assessment, behavioral testing |
Journal of neuroinflammation |
Medium |
37817190
|