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C57Bl/6 splenocytes were stained with 0.25 ug APC-Cyanine7 Anti-Mouse CD4 (25-0041) (solid line) or 0.25 ug APC-Cyanine7 Rat IgG2b isotype control (dashed line).

APC-Cyanine7 Anti-Mouse CD4 (GK1.5)

SKU 25-0041-U025
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The GK1.5 antibody reacts with mouse CD4, a 55 kDa protein which acts as a co-receptor for the T cell receptor (TCR) in its interaction with MHC Class II molecules on antigen-presenting cells. The extracellular domain of CD4 binds to the beta-2 domain of MHC Class II, while its cytoplasmic tail provides a binding site for the tyrosine kinase lck, facilitating the signaling cascade that initiates T cell activation. CD4 is typically expressed on thymocytes, certain mature T cell populations such as Th17 and T regulatory (Treg) cells, as well as on dendritic cells.

The GK1.5 antibody is widely used as a phenotypic marker for CD4 expression. If used together, the GK1.5 antibody and an alternative antibody, Anti-Mouse CD4 clone RM4-5, will "compete" for binding, i.e. RM4-5 is able to block GK1.5 binding to cells. In contrast, the Anti-Mouse CD4 clone RM4-4 does not block binding of the GK1.5 antibody to cells (Arora S et al. 2006. Infect. Immun. 74: 4339-4348). The GK1.5 antibody is also reported to be cross-reactive with Syrian hamster CD4.

Recent Citations:

Fu Z, Dean JW, Xiong L, et al. Mitochondrial transcription factor A in RORγt+ lymphocytes regulate small intestine homeostasis and metabolism. Nat Commun. 2021 Jul 22;12(1):4462. doi: 10.1038/s41467-021-24755-9. PMID: 34294718.

» View on Nature Communications

Name APC-Cyanine7 Anti-Mouse CD4 (GK1.5)
Cat. No. 25-0041
Alternative Names L3T4, T7
Gene ID 12504
Clone GK1.5
Isotype GK1.5
Reactivity Mouse
Cross Reactivity Syrian Hamster
Format APC-Cyanine7
Application Flow Cytometry
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