Biolegend, 317454, Ultra-LEAF™ Purified anti-human CD4 Antibody, 1mg

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.
1mg
Verified Reactivity: Human, Cynomolgus, Rhesus
Reported Reactivity: Chimpanzee
Antibody Type: Monoclonal
Host Species: Mouse
Immunogen: Human peripheral T cells
Formulation: 0.2 µm filtered in phosphate-buffered solution, pH 7.2, containing no preservative.
Endotoxin Level: Less than 0.01 EU/µg of the protein (< 0.001 ng/µg of the protein) as determined by the LAL test.
Preparation: The Ultra-LEAF™ (Low Endotoxin, Azide-Free) antibody was purified by affinity chromatography.
Concentration: The antibody is bottled at the concentration indicated on the vial, typically between 2 mg/mL and 3 mg/mL. Older lots may have also been bottled at 1 mg/mL. To obtain lot-specific concentration and expiration, please enter the lot number in our Certificate of Analysis online tool.
Storage & Handling: The antibody solution should be stored undiluted between 2°C and 8°C. This Ultra-LEAF™ solution contains no preservative; handle under aseptic conditions.
Application: FC - Quality testedIHC-F - Reported in the literature, not verified in house
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 ≤ 2.0 µg per million cells in 100 µL volume. It is recommended that the reagent be titrated for optimal performance for each application.
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.
RRID: AB_2876620 (BioLegend Cat. No. 317453) AB_2876620 (BioLegend Cat. No. 317454)
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.
Q: Do you guarantee that your antibodies are totally pathogen free?
A: BioLegend does not test for pathogens in-house aside from the GoInVivo™ product line. However, upon request, this can be tested on a custom basis with an outside, independent laboratory.
Q: Does BioLegend test each Ultra-LEAF™ antibody by functional assay?
A: No, BioLegend does not test Ultra-LEAF™ antibodies by functional assays unless otherwise indicated. Due to the possible complexities and variations of uses of biofunctional antibodies in different assays and because of the large product portfolio, BioLegend does not currently perform functional assays as a routine QC for the antibodies. However, we do provide references in which the antibodies were used for functional assays and we do perform QC to verify the specificity and quality of the antibody based on our strict specification criteria.
Q: Does BioLegend test each Ultra-LEAF™ antibody for potential pathogens?
A: No, BioLegend does not test for pathogens in-house unless otherwise indicated.  However, we can recommend an outside vendor to perform this testing as needed.
Q: Have you tested this Ultra-LEAF™ antibody for in vivo or in vitro applications?
A: We don't test our antibodies for in vivo or in vitro applications unless otherwise indicated. Depending on the product, the TDS may describe literature supporting usage of a particular product for bioassay. It may be best to further consult the literature to find clone specific information.