CD3 epsilon Protein, Human (HEK293, His)

CD3 epsilon is an important component of the TCR-CD3 complex on T lymphocytes and promotes TCR-mediated signaling. When APC activates the TCR, CD3 epsilon, together with CD3D, CD3G, and CD3Z, transmits signals across the cell membrane through ITAMs. CD3 epsilon Protein, Human (HEK293, His) is the recombinant human-derived CD3 epsilon protein, expressed by HEK293 , with C-6*His labeled tag.

CD3 epsilon, an integral component of the TCR-CD3 complex on the surface of T-lymphocytes, plays a crucial role in the adaptive immune response. As antigen-presenting cells (APCs) activate the T-cell receptor (TCR), CD3 epsilon, along with other CD3 chains (CD3D, CD3G, and CD3Z), facilitates the transmission of TCR-mediated signals across the cell membrane. Containing immunoreceptor tyrosine-based activation motifs (ITAMs) in its cytoplasmic domain, CD3 epsilon undergoes phosphorylation by Src family protein tyrosine kinases LCK and FYN upon TCR engagement, leading to the activation of downstream signaling pathways. Beyond its role in signal transduction, CD3 epsilon is essential for proper T-cell development, initiating the assembly of the TCR-CD3 complex by forming the heterodimers CD3D/CD3E and CD3G/CD3E. Additionally, CD3 epsilon is involved in the internalization and cell surface down-regulation of TCR-CD3 complexes through endocytosis sequences present in its cytosolic region. The TCR-CD3 complex comprises CD3D/CD3E and CD3G/CD3E heterodimers, which preferentially associate with TCRalpha and TCRbeta, forming trimers that interact with CD3Z homodimers to complete the hexameric TCR-CD3 complex. Alternatively, TCRgamma and TCRdelta can replace TCRalpha and TCRbeta. CD3 epsilon's interactions with CD6, NCK1, and NUMB further highlight its pivotal role in orchestrating T-cell activation, development, and internalization processes.

1.Measured by its binding ability in a functional ELISA. Immobilized Human CD3 epsilon at 10 μg/mL (100 μL/well) can bind Anti- CD3 epsilon antibody, the ED₅₀ is 3-15 ng/mL.
2.Loaded Cevostamab (HY-P99601) on AHC2 biosensor, can bind CD3 epsilon Protein, Human (HEK293, His) with an affinity constant of 3.265×10^-11 M as determined in BLI assay.
3.Measured by its binding ability in a functional ELISA. Immobilized Human CD3E-His at 2 μg/mL (100 μL/well) can bind Anti-Human/Monkey CD3E Antibody. The ED₅₀ of Anti-Human/Monkey CD3E Antibody is 3-15 ng/mL.

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  10 μg/mL (100 μL/well) of immobilized Human CD3E-His can bind Human Anti-CD3 with an ED₅₀ value of 10.5 ng/mL.
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  Loaded Cevostamab (HY-P99601) on AHC2 biosensor, can bind CD3 epsilon Protein, Human (HEK293, His) with an affinity constant of 3.265E-11 M as determined in BLI assay.

Human

HEK293

C-6*His

P07766 (D23-D126)

916  [NCBI]

Extracellular Domain

DGNEEMGGITQTPYKVSISGTTVILTCPQYPGSEILWQHNDKNIGGDEDDKNIGSDEDHLSLKEFSELEQSGYYVCYPRGSKPEDANFYLYLRARVCENCMEMD

Approximately 18-21 kDa, based on SDS-PAGE under reducing conditions.

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  ≥ 95%, as determined by reducing SDS-PAGE.

Lyophilized powder

1.Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.4.
2.Lyophilized from a 0.22 μm filtered solution of PBS, pH 7.4, 8% trehalose.
Please refer to the lot-specific COA for specific buffer information.

<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.