Biolegend, 317421, Alexa Fluor® 647 anti-human CD4 Antibody, 25tests

CD4, also known as T4, is a 55 kD single-chain type I transmembrane glycoprotein expressed on most thymocytes, a subset of T cells, and monocytes/macrophages. CD4, a member of the Ig superfamily, recognizes antigens associated with MHC class II molecules and participates in cell-cell interactions, thymic differentiation, and signal transduction. CD4 acts as a primary receptor for HIV, binding to HIV gp120. CD4 has also been shown to interact with IL-16.
25tests
Verified Reactivity: Human, Cynomolgus, Rhesus
Reported Reactivity: Chimpanzee
Antibody Type: Monoclonal
Host Species: Mouse
Immunogen: Human peripheral T cells
Formulation: Phosphate-buffered solution, pH 7.2, containing 0.09% sodium azide and BSA (origin USA)
Preparation: The antibody was purified by affinity chromatography and conjugated with Alexa Fluor® 647 under optimal conditions.
Concentration: Lot-specific (to obtain lot-specific concentration, please enter the lot number in our Concentration and Expiration Lookup or Certificate of Analysis online tools.)
Storage & Handling: The antibody solution should be stored undiluted between 2°C and 8°C, and protected from prolonged exposure to light. Do not freeze.
Application: FC - Quality tested IHC-F - Verified
Recommended Usage: Each lot of this antibody is quality control tested by immunofluorescent staining with flow cytometric analysis. For flow cytometric staining, the suggested use of this reagent is 5 µl per million cells in 100 µl staining volume or 5 µl per 100 µl of whole blood. For immunohistochemical staining on frozen tissue sections, the suggested use of this reagent is 5.0 - 10 µg per ml. It is recommended that the reagent be titrated for optimal performance for each application. * Alexa Fluor® 647 has a maximum emission of 668 nm when it is excited at 633nm / 635nm. Alexa Fluor® and Pacific Blue™ are trademarks of Life Technologies Corporation.View full statement regarding label licenses
Excitation Laser: Red Laser (633 nm)
Application Notes: The OKT4 antibody binds to the D3 domain of CD4 and does not block HIV binding. Additional reported applications (for the relevant formats) include: immunohistochemistry of frozen sections and blocking of T cell activation. This clone was tested in-house and does not work on formalin fixed paraffin-embedded (FFPE) tissue. The Ultra-LEAF™ purified antibody (Endotoxin < 0.01 EU/µg, Azide-Free, 0.2 µm filtered) is recommended for functional assays (Cat. No. 317453 and 317454). In a small subset of individuals, the OKT4 clone does not bind to CD4 due to polymorphisms in CD4.9
Application References(PubMed link indicates BioLegend citation): Knapp W, et al. 1989. Leucocyte Typing IV. Oxford University Press. New York. Reinherz EL, et al. 1979. Proc. Natl. Acad. Sci. 76:4061. Kmieciak M, et al. 2009. J. Transl. Med. 7:89. (FC) PubMed Cicin-Sain L, et al. 2010. J. Immunol. 184:6739. PubMed Rosenzweig M, et al. 2001. J. Med. Primatol. 30:36. Linder J, et al. 1987. Am. J. Pathol. 127:1. Boche D, et al. 1999. J. Neurovirol. 5:232. (IHC) Reinherz EL, et al. 1979. Proc. Natl. Acad. Sci. USA. 76:4061. (Immunogen) Lederman S, et al. 1991. Mol Immunol. 28:1171-81.
Product Citations: Izquierdo-Useros N, et al. 2012. PLoS Biol. 10:e1001448. PubMed Greenwood EJD et al. 2019. Cell Rep. 27(5):1579-1596 . PubMed Baleeiro RB, et al. 2022. Oncoimmunology. 11:2080329. PubMed Veazey R, et al. 2016. Mucosal Immunol. 10.1038/mi.2015. PubMed Carter JA, et al. 2020. Cell Systems. 9(5):475-482.e4.. PubMed
RRID: AB_571941 (BioLegend Cat. No. 317422)
Structure: Ig superfamily, type I transmembrane glycoprotein, 55 kD
Distribution: T cell subset, majority of thymocytes, monocytes/macrophages
Function: MHC class II co-receptor, lymphocyte adhesion, thymic differentiation, HIV receptor
Ligand/Receptor: MHC class II molecules, HIV gp120, IL-16
Cell Type: Macrophages, Monocytes, T cells, Thymocytes, Tregs
Biology Area: Immunology
Molecular Family: CD Molecules
Antigen References: 1. Center D, et al. 1996. Immunol. Today 17:476. 2. Gaubin M, et al. 1996. Eur. J. Clin. Chem. Clin. Biochem. 34:723.
Gene ID: 920
UniProt: View information about CD4 on UniProt.org
Clone: OKT4
Regulatory Status: RUO
Workshop: HCDM listed
Other Names: T4
Isotype: Mouse IgG2b, κ
Q: I am unable to see expression of T cell markers such as CD3 and CD4 post activation.
A: TCR-CD3 complexes on the T-lymphocyte surface are rapidly downregulated upon activation with peptide-MHC complex, superantigen or cross-linking with anti-TCR or anti-CD3 antibodies. PMA/Ionomycin treatment has been shown to downregulate surface CD4 expression. Receptor downregulation is a common biological phenomenon and so make sure that your stimulation treatment is not causing it in your sample type.