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Anti-CD31 Antibody, clone 4E20 , ZooMAb® Rabbit Monoclonal

enhanced validationgreener alternative

recombinant, expressed in HEK 293 cells

Platelet endothelial cell adhesion

biological source

rabbit (recombinant)


expressed in HEK 293 cells



antibody form

purified antibody

antibody product type

primary antibodies


4E20, recombinant monoclonal

product line

ZooMAb® learn more



mol wt

calculated mol wt 82.52 kDa
observed mol wt 130 kDa

species reactivity



antibody small pack of 25 μL

greener alternative product characteristics

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enhanced validation

recombinant expression
Learn more about Antibody Enhanced Validation


flow cytometry: suitable
immunocytochemistry: suitable
immunohistochemistry: suitable
western blot: suitable



UniProt accession no.

greener alternative category

shipped in


storage temp.


Gene Information

human ... PECAM1(5175)

General description

ZooMAb antibodies represent an entirely new generation of recombinant monoclonal antibodies.

Each ZooMAb antibody is manufactured using our proprietary recombinant expression system, purified to homogeneity, and precisely dispensed to produce robust and highly reproducible lot-to-lot consistency. Only top-performing clones are released for use by researchers. Each antibody is validated for high specificity and affinity across multiple applications, including its most commonly used application. ZooMAb antibodies are reliably available and ready to ship when you need them.

Learn more about ZooMAb here.


Clone 4E20 is a ZooMAb rabbit recombinant monoclonal antibody that specifically detects human Platelet endothelial cell adhesion molecule (PECAM-1). It targets an epitope within the cytoplasmic domain from the C-terminal region.


GST/His-tagged recombinant fragment corresponding to 85 amino acids from the C-terminal, cytoplasmic domain of human Platelet endothelial cell adhesion molecule (CD31; PECAM-1).


Anti-CD31, clone 4E20 ZooMAb, Cat. No. ZRB1216, is a highly specific rabbit recombinant monoclonal antibody that targets Platelet endothelial cell adhesion molecule (CD31 / PECAM-1) and has been tested for use in Flow Cytometry, Immunocytochemistry, Immunohistochemistry, and Western Blotting.
Western Blotting Analysis: A 1:1,000 dilution from a representative lot detected CD31 in THP1, HL60, and Jurkat cell lysates.

Immunohistochemistry (Paraffin) Analysis: A 1:10,000 dilution from a representative lot detected CD31 in human tonsil tissue sections.

Flow Cytometry Analysis: 0.2 μg/mL from a representative lot detected CD31 in THP-1 cells.

Immunocytochemistry Analysis: A 1:100 dilution from a representative lot detected CD31 in THP-1 cell line.

Note: Actual optimal working dilutions must be determined by end user as specimens and experimental conditions may vary.

Target description

Platelet endothelial cell adhesion molecule (UniProt: P16284; also known as PECAM-1, EndoCAM. GPIIA′, PECA1, CD31) is encoded by the PECAM1 gene (Gene ID: 5175) in human. PECAM-1 is a single-pass type I membrane protein that is synthesized with a signal peptide (aa 1-27) that is subsequently cleaved to generate the mature protein with a large extracellular region (aa 28-601) that contains six Ig-like C2-type domains, followed by a transmembrane segment (aa 602-620) and a cytoplasmic tail (aa. 621-738 of isoform Long) that plays an essential role in PECAM-1-mediated cellular signaling. It contains six Ig-like C2-type domains and Ig-like C2-type domains 2 and 3 contribute to formation of the complex with BDKRB2 and in regulation of its activity. PECAM-1 is essential for leukocyte transendothelial migration (TEM) under most inflammatory conditions. It is expressed on platelets and leukocytes and is primarily concentrated at the borders between endothelial cells. Six isoforms of PECAM-1 have been described that are produced by alternative splicing. Isoform Long predominates in all tissues examined, whereas Delta 12 isoform is detected only in trachea and isoform Delta14-15 are only detected in lung tissue. Isoform Delta14 is detected in all tissues examined with the strongest expression in heart. Isoform Delta15 is expressed in brain, testis, ovary, cell surface of platelets, human umbilical vein endothelial cells (HUVECs), Jurkat T-cell leukemia, human erythroleukemia and U-937 histiocytic lymphoma cell lines. Tyrosine 690 residue plays a critical role in TEM and is required for efficient trafficking of PECAM-1 to and from the lateral border recycling compartment (LBRC) and is also required for the LBRC membrane to be targeted around migrating leukocytes. PECAM-1 also prevents phagocyte ingestion of closely apposed viable cells by transmitting ′detachment′ signals, and changes function on apoptosis, promoting tethering of dying cells to phagocytes. This ZooMAb recombinant monoclonal antibody, generated by our propriety technology, offers significantly enhanced specificity, affinity, reproducibility, and stability over conventional monoclonals.

Physical form

Purified recombinant rabbit monoclonal antibody IgG, lyophilized in PBS with 5% Trehalose, normal appearance a coarse or translucent resin. Contains no biocide or preservatives, such as azide, or any animal by-products. Larger pack sizes provided as multiples of 25 μL.


30 μg/mL after reconstitution at 25 μL. Please refer to guidance on suggested starting dilutions and/or titers per application and sample type.

Storage and Stability

Recommend storage of lyophilized product at 2-8°C; Before reconstitution, micro-centrifuge vials briefly to spin down material to bottom of the vial; Reconstitute each vial by adding 25 μL of filtered lab grade water or PBS; Reconstituted antibodies can be stored at 2-8°C, or -20°C for long term storage. Avoid repeated freeze-thaws.

Legal Information

ZooMAb is a registered trademark of Merck KGaA, Darmstadt, Germany


Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.

Storage Class Code

11 - Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Enter Lot Number to search for Certificate of Analysis (COA).

Certificate of Origin

Enter Lot Number to search for Certificate of Origin (COO).

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

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