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To Purchase # 14541T

14541T 1 Kit (8 x 20 µl) $509.00.0


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Product Includes Quantity Applications Reactivity MW(kDa) Isotype
CD3ε (CD3-12) Rat mAb 4443 20 µl
Western Blotting Immunoprecipitation Flow Cytometry
H M 21 Rat IgG1
Phospho-LAT (Tyr191) Antibody 3584 20 µl
Western Blotting Immunoprecipitation
H 36, 38 Rabbit 
Phospho-Lck (Tyr505) Antibody 2751 20 µl
Western Blotting Immunoprecipitation
H M 56 Rabbit 
Phospho-PLCγ1 (Tyr783) (D6M9S) Rabbit mAb 14008 20 µl
Western Blotting Immunoprecipitation Flow Cytometry
H M 155 Rabbit IgG
Phospho-Src Family (Tyr416) (D49G4) Rabbit mAb 6943 20 µl
Western Blotting Immunoprecipitation
H M R Mk 60 Rabbit IgG
Phospho-SLP-76 (Ser376) (D9D6E) Rabbit mAb 14745 20 µl
Western Blotting
H M 76 Rabbit IgG
Phospho-Zap-70 (Tyr319)/Syk (Tyr352) (65E4) Rabbit mAb 2717 20 µl
Western Blotting Immunofluorescence Flow Cytometry
H M 70, 72 Rabbit IgG
Phospho-Zap-70 (Tyr493)/Syk (Tyr526) Antibody 2704 20 µl
Western Blotting Immunoprecipitation
H 70 Rabbit 
Anti-rat IgG, HRP-linked Antibody 7077 100 µl
Western Blotting
Anti-rabbit IgG, HRP-linked Antibody 7074 100 µl
Western Blotting

Product Description

The T Cell Signaling Antibody Sampler Kit provides an economical means to investigate T cell receptor signaling. The kit contains primary and secondary antibodies to perform two western blot experiments per primary antibody.

Specificity / Sensitivity

Unless otherwise indicated, each antibody will recognize endogenous total levels of target protein, and modification state antibodies will only recognize target proteins phosphorylated at the indicated residue. Phospho-Lck (Tyr505) Antibody may cross-react with certain phosphorylated Src family members due to high sequence homology. Phospho-Src Family (Tyr416) (D49G4) Rabbit mAb may cross-react with other Src family members (Lyn, Fyn, Lck, Yes and Hck) when phosphorylated at equivalent sites, and may cross react with overexpressed phosphorylated RTKs. Phospho-Zap-70 (Tyr319)/Syk (Tyr352) (65E4) Rabbit mAb cross-reacts with endogenous levels of Syk when phosphorylated at Tyr352. Phospho-Zap-70 (Tyr493)/Syk (Tyr526) Antibody cross-reacts with endogenous levels of Syk when phosphorylated at Tyr526.

Source / Purification

Monoclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to a region surrounding Pro184 of human CD3ε, and with a synthetic phosphopeptide corresponding to residues surrounding Tyr783 of human PLCγ1 protein, Tyr416 of human Src protein, Ser376 of human SLP-76 protein, and Tyr319 of human Zap-70 protein. Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues around Tyr191 of human LAT protein, Tyr505 of human Lck protein, and Tyr493 of human Zap-70 protein. Antibodies are purified by protein A and peptide affinity chromatography.

When T cells encounter antigens via the T cell receptor (TCR), information about the quantity and quality of antigens is relayed to the intracellular signal transduction machinery (1). This activation process depends mainly on CD3 (Cluster of Differentiation 3), a multiunit protein complex that directly associates with the TCR α and ß chains. CD3 is composed of four polypeptides: ζ, γ, ε and δ. Each of these polypeptides contains at least one immunoreceptor tyrosine-based activation motif (ITAM) (2). The Src family kinases Lck and Fyn are recruited to the TCR complex upon stimulation and activate the downstream tyrosine kinases to initiate signaling. Phosphorylation of Lck at Tyr394 leads to an increase in Lck activity while phosphorylation of Tyr505 in the Lck carboxy-terminal tail down-regulates Lck catalytic activity (3). Zap-70 and Syk are rapidly phosphorylated on several tyrosine residues through autophosphorylation and transphosphorylation by Src family tyrosine kinases.  Activation loop phosphorylation of Zap-70 at Tyr493 and Syk at Tyr526 leads to complete activation of both kinases (4).  Subsequent phosphorylation of other tyrosine residues within the kinase interdomain B region, including Zap-70 at Tyr315 and Zap-70 at Tyr 319, create docking sites for downstream signaling molecules.  Zap-70 and Syk phosphorylate the transmembrane adaptor protein LAT at multiple, conserved tyrosine residues within SH2 binding motifs, exposing these motifs as docking sites for downstream signaling targets (5,6). The phosphorylation of LAT at Tyr171 and Tyr191 enables the binding of Grb2, Gads/SLP-76, PLCγ1, and PI3 kinase. The adapter protein SLP-76 is phosphorylated at Tyr113 and Tyr128, allowing for binding of the Grb2-like adapter Gads.  Phosphorylation of SLP-76 at Ser376 by hematopoietic progenitor kinase 1 (HPK1) induces interaction with 14-3-3ε and down-regulates TCR signaling (7,8).  Phosphoinositide-specific phospholipase PLCγ1 enzyme activity is also stimulated by Zap-70 and Syk phosphorylation on Tyr783, Tyr711, and Tyr1253, resulting in robust PI-4,5-P2 hydrolysis (9).

1.  Kuhns, M.S. et al. (2006) Immunity 24, 133-9.

2.  Pitcher, L.A. and van Oers, N.S. (2003) Trends Immunol 24, 554-60.

3.  Chow, L.M. et al. (1993) Nature 365, 156-60.

4.  Wang, H. et al. (2010) Cold Spring Harb Perspect Biol 2, a002279.

5.  Zhang, W. et al. (1998) Cell 92, 83-92.

6.  Paz, P.E. et al. (2001) Biochem J 356, 461-71.

7.  Shui, J.W. et al. (2007) Nat Immunol 8, 84-91.

8.  Di Bartolo V et al. (2007) J Exp Med 204, 681–91

9.  Beach, D. et al. (2007) J Biol Chem 282, 2937-46.

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T Cell Signaling Antibody Sampler Kit