CD26/Dipeptidyl Peptidase 4 Protein, Human (HEK293, His)

The CD26/dipeptidyl peptidase 4 protein is a cell surface glycoprotein receptor that induces T cell proliferation and NF-kappa-B activation. CD26 also works with FAP to promote pericellular proteolysis, endothelial cell migration, and invasion of the extracellular matrix. CD26/Dipeptidyl Peptidase 4 Protein, Human (HEK293, His) is the recombinant human-derived CD26/Dipeptidyl Peptidase 4 protein, expressed by HEK293 , with C-6*His labeled tag.

CD26/Dipeptidyl Peptidase 4 protein, a cell surface glycoprotein receptor, plays a pivotal role in the costimulatory signal essential for T-cell receptor (TCR)-mediated T-cell activation. Functioning as a positive regulator of T-cell coactivation, CD26 interacts with ADA, CAV1, IGF2R, and PTPRC, leading to T-cell proliferation and NF-kappa-B activation in a T-cell receptor/CD3-dependent manner. Its binding to CAV1 and CARD11 induces T-cell proliferation, while its interaction with ADA regulates lymphocyte-epithelial cell adhesion. In association with FAP, CD26 is involved in pericellular proteolysis of the extracellular matrix, contributing to the migration and invasion of endothelial cells. Additionally, it may play a role in promoting lymphatic endothelial cell adhesion, migration, and tube formation. Acting as a serine exopeptidase with dipeptidyl peptidase activity, CD26 regulates various physiological processes by cleaving peptides in the circulation, including chemokines, mitogenic growth factors, neuropeptides, and peptide hormones. Notably, CD26 acts as a receptor for the human coronavirus MERS-CoV-2 during microbial infection.

Measured by its ability to cleave the fluorogenic peptide substrate, Gly-Pro-7-amido-4-methylcoumarin (GP-AMC). Read at excitation and emission wavelengths of 380 nm and 460 nm .The specific activity is 39568.285 pmol/min/µg, as measured under the described conditions.

Materials
Assay buffer: 25 mM Tris, pH 8.0
CD26/Dipeptidyl Peptidase 4 Protein, Human (HEK293, His) (HY-P70017)
Substrate: Gly-Pro-AMC hydrobromide (HY-137834)
Standard: 7-Amino-4-methylcoumarin (AMC, HY-D0027)

Procedure
1. Dilute AMC to 0, 3.125, 6.25, 12.5, 25, 50, and 100 μmol/L respectively with Assay Buffer. Add 100 μL of each dilution to black microplate wells. Set excitation and emission wavelengths to 380 nm and 460 nm (top read) respectively, and read in kinetic mode for 5 minutes. Plot a standard curve with the measured RFU as the abscissa and the amount of standard substance as the ordinate, and obtain the standard curve equation.
2. Dilute Human CD26 to 2 μg/mL in assay buffer.
3. Dilute the substrate to 200 μM in assay buffer.
4. Add 50 μL of 2 μg/mL Human CD26 to the plate, then add 50 μL of 200 μM substrate to initiate the reaction. For substrate blank, load 50 μL of assay buffer and 50 μL of substrate.
5. Read in kinetic mode for 5 minutes at excitation wavelength of 380 nm and emission wavelength of 460 nm respectively.
6. Calculate the specific activity:

Human

HEK293

C-6*His

P27487 (N29-P766)

1803  [NCBI]

Extracellular Domain

NKGTDDATADSRKTYTLTDYLKNTYRLKLYSLRWISDHEYLYKQENNILVFNAEYGNSSVFLENSTFDEFGHSINDYSISPDGQFILLEYNYVKQWRHSYTASYDIYDLNKRQLITEERIPNNTQWVTWSPVGHKLAYVWNNDIYVKIEPNLPSYRITWTGKEDIIYNGITDWVYEEEVFSAYSALWWSPNGTFLAYAQFNDTEVPLIEYSFYSDESLQYPKTVRVPYPKAGAVNPTVKFFVVNTDSLSSVTNATSIQITAPASMLIGDHYLCDVTWATQERISLQWLRRIQNYSVMDICDYDESSGRWNCLVARQHIEMSTTGWVGRFRPSEPHFTLDGNSFYKIISNEEGYRHICYFQIDKKDCTFITKGTWEVIGIEALTSDYLYYISNEYKGMPGGRNLYKIQLSDYTKVTCLSCELNPERCQYYSVSFSKEAKYYQLRCSGPGLPLYTLHSSVNDKGLRVLEDNSALDKMLQNVQMPSKKLDFIILNETKFWYQMILPPHFDKSKKYPLLLDVYAGPCSQKADTVFRLNWATYLASTENIIVASFDGRGSGYQGDKIMHAINRRLGTFEVEDQIEAARQFSKMGFVDNKRIAIWGWSYGGYVTSMVLGSGSGVFKCGIAVAPVSRWEYYDSVYTERYMGLPTPEDNLDHYRNSTVMSRAENFKQVEYLLIHGTADDNVHFQQSAQISKALVDVGVDFQAMWYTDEDHGIASSTAHQHIYTHMSHFIKQCFSLP

86-130 kDa

• 
  Greater than 95% as determined by reducing SDS-PAGE.

Lyophilized powder.

Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.4 or 20 mM PB, 150 mM NaCl, pH 7.4.

<1 EU/μg, determined by LAL method.

It is not recommended to reconstitute to a concentration less than 100 μg/mL in ddH₂O. For long term storage it is recommended to add a carrier protein (0.1% BSA, 5% HSA, 10% FBS or 5% Trehalose).

Stored at -20°C for 2 years from date of receipt. After reconstitution, it is stable at 4°C for 1 week or -20°C for longer (with carrier protein). It is recommended to freeze aliquots at -20°C or -80°C for extended storage.

Room temperature in continental US; may vary elsewhere.