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Product listing: CBX4 (E6L7X) Rabbit mAb, UniProt ID O00257 #30559 to CD4 (RM4-5) Rat mAb (violetFluor™ 450 Conjugate), UniProt ID P06332 #92599

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

Application Methods: Chromatin IP, Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: The polycomb group (PcG) proteins contribute to the maintenance of cell identity, stem cell self-renewal, cell cycle regulation, and oncogenesis by maintaining the silenced state of genes that promote cell lineage specification, cell death, and cell-cycle arrest (1-4). PcG proteins exist in two complexes that cooperate to maintain long-term gene silencing through epigenetic chromatin modifications. The first complex, EED-EZH2, is recruited to genes by DNA-binding transcription factors and methylates histone H3 on Lys27. This histone methyl-transferase activity requires the Ezh2, Eed, and Suz12 subunits of the complex (5). Histone H3 methylation at Lys27 facilitates the recruitment of the second complex, PRC1, which ubiquitinylates histone H2A on Lys119 (6). CBX4 is a component of the PRC1 complex, which together with Ring1 strongly enhances the E3 ubiquitin ligase activity of the Ring2 catalytic subunit (7,8). CBX4 itself is a SUMO E3 ligase, and its function influences EMT, DNA damage response, tumor angiogenesis, and self-renewal (9-13).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: Caspase-1, or interleukin-1ß converting enzyme (ICE/ICEα), is a class I cysteine protease, which also includes caspases -4, -5, -11, and -12. Caspase-1 cleaves inflammatory cytokines such as pro-IL-1ß and interferon-γ inducing factor (IL-18) into their mature forms (1,2). Like other caspases, caspase-1 is proteolytically activated from a proenzyme to produce a tetramer of its two active subunits, p20 and p10. Caspase-1 has a large amino-terminal pro-domain that contains a caspase recruitment domain (CARD). Overexpression of caspase-1 can induce apoptosis (3). Mice deficient in caspase-1, however, have no overt defects in apoptosis but do have defects in the maturation of pro-IL-1β and are resistant to endotoxic shock (4,5). At least six caspase-1 isoforms have been identified, including caspase-1 α, β, γ, δ, ε and ζ (6). Most caspase-1 isoforms (α, β, γ and δ) produce products between 30-48 kDa and induce apoptosis upon over-expression. Caspase-1 ε typically contains only the p10 subunit, does not induce apoptosis and may act as a dominant negative. The widely expressed ζ isoform of caspase-1 induces apoptosis and lacks 39 amino-terminal residues found in the α isoform (6). Activation of caspase-1 occurs through an oligomerization molecular platform designated the "inflammasome" that includes caspase-5, Pycard/Asc, and NALP1 (7).

$260
100 µl
APPLICATIONS
REACTIVITY
All Species Expected

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: The CRISPR associated protein 9 (Cas9) is an RNA-guided DNA nuclease and part of the CRISPR antiviral immunity system that provides adaptive immunity against extra chromosomal genetic material (1). The CRISPR antiviral mechanism of action involves three steps: (i), acquisition of foreign DNA by host bacterium; (ii), synthesis and maturation of CRISPR RNA (crRNA), followed by the formation of RNA-Cas nuclease protein complexes; and (iii), target interference through recognition of foreign DNA by the complex and its cleavage by Cas nuclease activity (2). The type II CRISPR/Cas antiviral immunity system provides a powerful tool for precise genome editing and has potential for specific gene regulation and therapeutic applications (3). The Cas9 protein and a guide RNA consisting of a fusion between a crRNA and a trans-activating crRNA (tracrRNA) must be introduced or expressed in a cell. A 20-nucleotide sequence at the 5' end of the guide RNA directs Cas9 to a specific DNA target site. As a result, Cas9 can be "programmed" to cut various DNA sites both in vitro and in cells and organisms. CRISPR/Cas9 genome editing tools have been used in many organisms, including mouse and human cells (4,5). Research studies demonstrate that CRISPR can be used to generate mutant alleles or reporter genes in rodents and primate embryonic stem cells (6-8).Cas9 (S. aureus) is a Cas9 ortholog that is smaller, but as efficient, as the more commonly used Cas9 ortholog, Cas9 (S. Pyogenes) (9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Calcium/Calmodulin-dependent Protein Kinase Kinase 2 (CaMKK2) is a member of the CaMK family that contains a central Ser/Thr kinase domain followed by a regulatory domain consisting of overlapping autoinhibitory and CaM-binding regions (1). CaMKK2 can be distinguished from other CaMK family members by the presence of a unique Pro/Arg/Gly-rich insert following the ATP-binding domain (2). CaMKK2 phosphorylates CaMKI at Thr177 and CaMKIV at Thr200 (3). CaMKK2 also phosphorylates AMPKα in response to calcium (4). CaMKK2 has been implicated in long-term memory formation (5) and adipocyte development (6). CaMKK2 is phosphorylated at Ser511 by death-associated protein kinase (DAPK) in a signaling cascade thought to be involved in neuronal death (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Calretinin (29 kDa calbindin, calbindin 2) is a calcium-binding protein of the EF-hand family encoded by the CALB2 gene. It is differentially expressed from homologous family member calbindin-d28k in distinct neuronal populations of the retina, auditory system, and cerebellar granule cells (1, 2), and acts as a marker for specific neuronal subsets of the subthalamic nucleus and the substantia nigra (3). Calretinin has been shown to play an important role in modulating neuronal excitability and the induction of long-term potentiation (1). Research has shown that, pathologically, calretinin is a selective marker for epithelial mesothelioma, making it a diagnostic tool to differentiate from adenocarcinomas (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The Mitotic Checkpoint Complex (MCC), which contains Bub1, Bub1b, Bub3, Mad2, and Cdc20, controls chromosome segregation and monitors kinetochore-microtubule interactions (1). During mitosis, the MCC complex inhibits the ubiquitin ligase activity of the Anaphase Promoting Complex/Cyclosome (APC/C), thereby preventing cells with unaligned chromosomes from prematurely entering anaphase (2). Research studies have shown that Bub1b and Bub1 kinases are mutated in several types of human malignancies including hematopoietic, colorectal, lung, and breast cancers (3). Biallelic mutations in Bub1b have been found in mosaic variegated aneuploidy syndrome and premature chromatid separation syndrome (4). Bub1b mouse germline knockouts are embryonic lethal with heterozygous animals displaying genetic instability, early aging phenotypes, and increased cancer susceptibility (5). Bub3 binds both Bub1 and Bub1b, facilitating their recruitment to kinetochores (6), and is required for functional microtubule-kinetochore interactions (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Branched-chain amino acids (BCAAs) leucine, isoleucine, and valine are essential amino acids in mammals, but elevated levels of BCAAs have been implicated in cardiovascular and metabolic disorders (1). The branched-chain α-keto acid dehydrogenase complex (BCKDH) catalyzes the rate-limiting step in the BCAA degradation pathway (2, 3). Branched-chain α-keto acid decarboxylase (BCKDH-E1) is one of three enzymatic components in this complex (3). The α subunit of BCKDH-E1 (BCKDH-E1α) is critical for the regulation of BCKDH. Phosphorylation of BCKDH-E1α was shown to play a key role in regulating the enzymatic activity of this complex (3-5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: BCAT1 and BCAT2 are cytosolic and mitochondrial branched chain aminotransferases, respectively (1,2). Research studies have implicated BCAT1 in distant metastasis in patients with advanced colorectal cancer (3). Disruption of BCAT2 in mice leads to higher levels of plasma branched-chain amino acids, reduced adiposity and body weight, and increased energy expenditure, suggesting its role in regulating insulin sensitivity (4).

$260
100 µl
REACTIVITY
Human

Background: BRCA1-Associated Protein 1 (BAP1) was originally identified as a BRCA1 associated, nuclear localized ubiquitin hydrolase that suppresses cell growth (1). The protein belongs to the UCH family of deubiquitinases, with a UCH domain in its amino-terminal segment and a BRCA1 interaction domain as well as a nuclear localization signal in its carboxy-terminal segment (1). Frequent gene locus rearrangement, deletion, and null mutation of BAP1 have been found in lung and breast cancers (1,2). In vivo mutation analysis of cancer cell line survival and animal tumorigenesis indicates that both the deubiquitinase activity and the nuclear localization signal are required for BAP1 function as a tumor suppressor (3). BAP1 does not have direct deubiquitination activity towards the autoubiquitinated BRCA1/BARD1 E3 complex (4), but its interaction with BARD1 inhibits BRCA1/BARD1 E3 activity by interfering with the complex dimerization process (5). In addition to its interaction with BRCA1/BARD1, BAP1 has also been shown to interact with and deubiquitinate HCF-1, thereby controlling its stability (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: The transcription factor ATF-2 (also called CRE-BP1) binds to both AP-1 and CRE DNA response elements and is a member of the ATF/CREB family of leucine zipper proteins (1). ATF-2 interacts with a variety of viral oncoproteins and cellular tumor suppressors and is a target of the SAPK/JNK and p38 MAP kinase signaling pathways (2-4). Various forms of cellular stress, including genotoxic agents, inflammatory cytokines, and UV irradiation, stimulate the transcriptional activity of ATF-2. Cellular stress activates ATF-2 by phosphorylation of Thr69 and Thr71 (2-4). Both SAPK and p38 MAPK have been shown to phosphorylate ATF-2 at these sites in vitro and in cells transfected with ATF-2. Mutations of these sites result in the loss of stress-induced transcription by ATF-2 (2-4). In addition, mutations at these sites reduce the ability of E1A and Rb to stimulate gene expression via ATF-2 (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Protein acetylation is a common modification that occurs both at lysine residues within proteins (ε-amino acetylation) and multiple amino acid residues at the amino terminus of proteins (α-amino acetylation). The N-α-acetyltransferase ARD1 homolog A protein (ARD1A, also known as NAA10) and the highly homologous N-α-acetyltransferase ARD1 homolog B protein (ARD1B, also known as ARD2 or NAA11) are mutually exclusive catalytic subunits of the amino-terminal acetyltransferase complex (NatA) (1-3). This complex, which consists of either ARD1A or ARD1B and the N-α-acetyltransferase 15 (NAA15) auxiliary protein, localizes to ribosomes where it functions to acetylate Ser-, Ala-, Gly-, Thr-, Cys-, Pro-, and Val- amino termini after initiator methionine cleavage during protein translation (1-5). Like ε-amino acetylation, amino-terminal α-amino acetylation functions to regulate protein stability, activity, cellular localization, and protein-protein interactions (4,5). Defects in ARD1A have been shown to cause amino-terminal acetyltransferase deficiency (NATD), which results in severe delays and defects in postnatal growth (6).In addition to functioning as amino-terminal acetyltransferases in the NatA complex, free ARD1A and ARD1B proteins regulate cell growth and differentiation through ε-amino acetylation of lysine residues in multiple target proteins, including the HIF-1α, β-catenin, and AP-1 transcription factors (7-9). ARD1A-mediated acetylation of HIF-1α at Lys532 under normoxic conditions enhances binding of VHL, leading to increased ubiquitination and degradation of HIF-1α and down-regulation of HIF-1α target genes involved in angiogenesis, apoptosis, cellular proliferation, and glucose metabolism (7). Decreased expression of ARD1A under hypoxic conditions contributes to the stabilization of HIF-1α and upregulation of target genes (7). ARD1A also promotes cell proliferation and tumorigenesis by acetylating and activating β-catenin and AP-1 transcription factors, leading to the stimulation of cyclin D1 expression (8,9). Interestingly, the acetyltransferase activity of ARD1A is regulated by autoacetylation at Lys136, which is required for the ability of ARD1A to promote proliferation and tumorigenesis (9). Research studies have shown that ARD1 proteins are over-expressed in multiple cancers, including breast, prostate, lung, and colorectal cancers (10-13).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Western Blotting

Background: Ape1 (Apurinic/Apyrimidic eEndonuclease 1), also known as Ref1 (Redox effector factor 1), is a multifunctional protein with several biological activities. These include roles in DNA repair and in the cellular response to oxidative stress. Ape1 initiates the repair of abasic sites and is essential for the base excision repair (BER) pathway (1). Repair activities of Ape1 are stimulated by interaction with XRCC1 (2), another essential protein in BER. Ape1 functions as a redox factor that maintains transcription factors in an active, reduced state but can also function in a redox-independent manner as a transcriptional cofactor to control different cellular fates such as apoptosis, proliferation and differentiation (3). Increased expression of Ape1 is associated with many types of cancers including cervical, ovarian, prostate, rhabdomyosarcomas and germ cell tumors (4). Ape1 has been shown to stimulate DNA binding of several transcription factors known to be involved in tumor progression such as Fos, Jun, NF-κB, PAX, HIF-1, HLF and p53 (4). Mutation of the Ape1 gene has also been associated with amyotrophic lateral sclerosis (ALS) (5,6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Amyloid β A4 precursor protein-binding family A member 2 (APBA2) is a neuronal adaptor protein that interacts with the amyloid β precursor protein (APP) (1). The amyloid β-protein (Aβ) is the principal component of amyloid plaques, a pathological hallmark of Alzheimer’s disease (2). APBA2 has been shown to stabilize APP metabolism and suppress the secretion of Aβ (3). APBA2 mediates interaction between APP and the neural type I membrane protein Alcadein (Alc) by linking their cytoplasmic domains, thereby forming a tripartite complex of the three proteins in neurons (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: Androgen receptor (AR), a zinc finger transcription factor belonging to the nuclear receptor superfamily, is activated by phosphorylation and dimerization upon ligand binding (1). This promotes nuclear localization and binding of AR to androgen response elements in androgen target genes. Research studies have shown that AR plays a crucial role in several stages of male development and the progression of prostate cancer (2,3).

$260
100 µl
REACTIVITY
Human

Background: Androgen receptor (AR), a zinc finger transcription factor belonging to the nuclear receptor superfamily, is activated by phosphorylation and dimerization upon ligand binding (1). This promotes nuclear localization and binding of AR to androgen response elements in androgen target genes. Research studies have shown that AR plays a crucial role in several stages of male development and the progression of prostate cancer (2,3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: AMPA- (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid), kainate-, and NMDA- (N-methyl-D-aspartate) receptors are the three main families of ionotropic glutamate-gated ion channels. AMPA receptors (AMPARs) are comprised of four subunits (GluR 1-4), which assemble as homo- or hetero-tetramers to mediate the majority of fast excitatory transmissions in the central nervous system. AMPARs are implicated in synapse formation, stabilization, and plasticity (1). In contrast to GluR 2-containing AMPARs, AMPARs that lack GluR 2 are permeable to calcium (2). Post-transcriptional modifications (alternative splicing, nuclear RNA editing) and post-translational modifications (glycosylation, phosphorylation) result in a very large number of permutations, fine-tuning the kinetic properties of AMPARs. Research studies have implicated activity changes in AMPARs in a variety of diseases including Alzheimer’s, amyotrophic lateral sclerosis (ALS), stroke, and epilepsy (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: Akt, also referred to as PKB or Rac, plays a critical role in controlling survival and apoptosis (1-3). This protein kinase is activated by insulin and various growth and survival factors to function in a wortmannin-sensitive pathway involving PI3 kinase (2,3). Akt is activated by phospholipid binding and activation loop phosphorylation at Thr308 by PDK1 (4) and by phosphorylation within the carboxy terminus at Ser473. The previously elusive PDK2 responsible for phosphorylation of Akt at Ser473 has been identified as mammalian target of rapamycin (mTOR) in a rapamycin-insensitive complex with rictor and Sin1 (5,6). Akt promotes cell survival by inhibiting apoptosis through phosphorylation and inactivation of several targets, including Bad (7), forkhead transcription factors (8), c-Raf (9), and caspase-9. PTEN phosphatase is a major negative regulator of the PI3 kinase/Akt signaling pathway (10). LY294002 is a specific PI3 kinase inhibitor (11). Another essential Akt function is the regulation of glycogen synthesis through phosphorylation and inactivation of GSK-3α and β (12,13). Akt may also play a role in insulin stimulation of glucose transport (12). In addition to its role in survival and glycogen synthesis, Akt is involved in cell cycle regulation by preventing GSK-3β-mediated phosphorylation and degradation of cyclin D1 (14) and by negatively regulating the cyclin dependent kinase inhibitors p27 Kip1 (15) and p21 Waf1/Cip1 (16). Akt also plays a critical role in cell growth by directly phosphorylating mTOR in a rapamycin-sensitive complex containing raptor (17). More importantly, Akt phosphorylates and inactivates tuberin (TSC2), an inhibitor of mTOR within the mTOR-raptor complex (18,19).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Adenosine deaminase (ADA) catalyzes adenosine degradation (1). Lack of this enzyme leads to the accumulation of toxic metabolites causing severe combined immunodeficiency (ADA-SCID), an autosomal recessive disorder. Differentiation and function of T cells, B cells, and natural killer cells are impaired in ADA-SCID patients leading to recurrent infections (1,2). Gene therapies for ADA-SCID were reported to correct the metabolic defect and restore the deficient immune function (1-3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Eukaryotic initiation factor 4E (eIF4E) binds to the mRNA cap structure to mediate the initiation of translation (1,2). eIF4E interacts with eIF4G, a scaffold protein that promotes assembly of eIF4E and eIF4A into the eIF4F complex (2). eIF4B is thought to assist the eIF4F complex in translation initiation. Upon activation by mitogenic and/or stress stimuli mediated by Erk and p38 MAPK, Mnk1 phosphorylates eIF4E at Ser209 in vivo (3,4). Two Erk and p38 MAPK phosphorylation sites in mouse Mnk1 (Thr197 and Thr202) are essential for Mnk1 kinase activity (3). The carboxy-terminal region of eIF4G also contains serum-stimulated phosphorylation sites, including Ser1108, Ser1148, and Ser1192 (5). Phosphorylation at these sites is blocked by the PI3 kinase inhibitor LY294002 and by the FRAP/mTOR inhibitor rapamycin.

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways (1,2). 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, β, γ, ε, σ, ζ, τ, and η that have been identified in mammals. The initially described α and δ isoforms are confirmed to be phosphorylated forms of β and ζ, respectively (3). Through their amino-terminal α helical region, 14-3-3 proteins form homo- or heterodimers that interact with a wide variety of proteins: transcription factors, metabolic enzymes, cytoskeletal proteins, kinases, phosphatases, and other signaling molecules (3,4). The interaction of 14-3-3 proteins with their targets is primarily through a phospho-Ser/Thr motif. However, binding to divergent phospho-Ser/Thr motifs, as well as phosphorylation independent interactions has been observed (4). 14-3-3 binding masks specific sequences of the target protein, and therefore, modulates target protein localization, phosphorylation state, stability, and molecular interactions (1-4). 14-3-3 proteins may also induce target protein conformational changes that modify target protein function (4,5). Distinct temporal and spatial expression patterns of 14-3-3 isoforms have been observed in development and in acute response to extracellular signals and drugs, suggesting that 14-3-3 isoforms may perform different functions despite their sequence similarities (4). Several studies suggest that 14-3-3 isoforms are differentially regulated in cancer and neurological syndromes (2,3).

$259
100 µg
This Cell Signaling Technology antibody is conjugated to APC and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: CD161/KLRB1 (Killer cell lectin-like receptor subfamily B member 1, also known as CLEC5B and NKR-P1A) is a type II transmembrane protein that is expressed on the majority of Natural Killer (NK) cells, NK T cells, and some T lymphocytes (1). CD161/KLRB1 is also expressed on Th17 cells, promotes their generation, and modulates their function (2). Engagement with its ligand lectin-like transcript 1 (LLT1) inhibits NK cell function, while LLT1 and CD161/KLRB1 interaction in the presence of a TCR signal enhances IFN-gamma production by T cells (3,4). There are several different CD161 isoforms in rodents and some function as activating receptors as well (5,6).

$259
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to APC and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: B-lymphocyte antigen CD20 (also known as MS4A1; Membrane-spanning 4-domains subfamily A member 1) is a cell surface phosphoprotein involved in the regulation of B cell activation and proliferation (1,2). It is commonly used as a marker to identify B cells and is expressed throughout B cell development, up until their differentiation into plasma cells. CD20 has no known ligand, and its expression and function are largely conserved between human and mouse (1-3). Evidence suggests that CD20 is necessary for store operated calcium (SOC) entry, which leads to elevated cytoplasmic calcium levels required for B cell activation (4-5). Anti-CD20 antibody immunotherapy depletes B cells by activation of the innate monocytic network and is a common treatment for B cell lymphomas, leukemias, and autoimmune diseases (6).

The Androgen Receptor Antibody Sampler Kit provides an economical means of detecting full-length Androgen Receptor and AR-V7 isoforms. The kit includes enough antibody to perform two western blot experiments with each primary antibody.
$249
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to redFluor™ 710 and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: The human leukocyte antigen (HLA) system is a gene complex encoding the major histocompatibility complex (MHC) proteins in humans. These cell surface proteins are responsible for the regulation of antigen-specific immunity in humans. HLA genes are highly polymorphic, allowing them to fine-tune the adaptive immune response. HLAs corresponding to MHC class I (HLA-A, B, and C) present small peptide antigens from inside the cell, approximately 8 to 10 amino acids in length, to CD8+ T lymphocytes in order to activate a cytotoxic T cell response. HLAs corresponding to MHC class II (HLA-DP, DM, DO, DQ, and DR) present antigens from outside of the cell, approximately 15 to 24 residues in length, to CD4+ T-helper cells, which in turn secrete cytokines and stimulate B cells to produce antibodies to that specific antigen. HLAs corresponding to MHC class III encode components of the complement system (1,2).

$249
100 µg
This Cell Signaling Technology antibody is conjugated to violetFluor™ 450 and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: Cluster of Differentiation 8 (CD8) is a disulphide-linked heterodimer consisting of the unrelated α and β subunits. Each subunit is a glycoprotein composed of a single extracellular Ig-like domain, a polypeptide linker, a transmembrane part and a short cytoplasmic tail. On T cells, CD8 is the coreceptor for the T cell receptor (TCR), and these two distinct structures recognize the Antigen–Major Histocompatibility Complex (MHC). Specifically, the Ig-like domain of CD8α interacts with the α3-domain of the MHC class I molecule. CD8 ensures specificity of the TCR–antigen interaction, prolongs the contact between the T cell and the antigen presenting cell, and the α chain recruits the tyrosine kinase Lck, which is essential for T cell activation (1).

$249
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to PE-Cy7® and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: The protein phosphatase (PTP) receptor CD45 is a type I transmembrane protein comprised of a pair of intracellular tyrosine phosphatase domains and a variable extracellular domain generated by alternative splicing (1). The catalytic activity of CD45 is a function of the first phosphatase domain (D1) while the second phosphatase domain (D2) may interact with and stabilize the first domain, or recruit/bind substrates (2,3). CD45 interacts directly with antigen receptor complex proteins or activates Src family kinases involved in the regulation of T- and B-cell antigen receptor signaling (1). Specifically, CD45 dephosphorylates Src-family kinases Lck and Fyn at their conserved negative regulatory carboxy-terminal tyrosine residues and upregulates kinase activity. Conversely, studies indicate that CD45 can also inhibit Lck and Fyn by dephosphorylating their positive regulatory autophosphorylation site. CD45 appears to be both a positive and a negative regulator that conducts signals depending on specific stimuli and cell type (1). Human leukocytes including lymphocytes, eosinophils, monocytes, basophils, and neutrophils express CD45, while erythrocytes and platelets are negative for CD45 expression (4).

$249
100 µg
This Cell Signaling Technology antibody is conjugated to PerCP-Cy5.5® and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: CD19 is a 95 kDa coreceptor, which amplifies the signaling cascade in B cells (1). On the B cell surface, CD19 associates with CD21, CD81 and Leu-13 to exert its function. The cytoplasmic tail of CD19 has nine conserved tyrosine residues playing critical roles in CD19 mediated function by coupling signaling molecules to the receptor (1). After B cell receptor or CD19 ligation, Tyr531 and Tyr500 of CD19 are progressively phosphorylated. This phosphorylation enables the coupling of PI3 kinase and Src family tyrosine kinase to CD19 and activates the PI3K and Src signaling pathways (2,3). Coligation of B cell receptor and CD19 also promotes Tyr409 phosphorylation in CD19. The phosphorylation at these sites enables its binding to Vav and mediates elevated intracellular calcium response, as well as the JNK pathway (4,5).

$249
100 µg
This Cell Signaling Technology antibody is conjugated to APC and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: CD19 is a 95 kDa coreceptor, which amplifies the signaling cascade in B cells (1). On the B cell surface, CD19 associates with CD21, CD81 and Leu-13 to exert its function. The cytoplasmic tail of CD19 has nine conserved tyrosine residues playing critical roles in CD19 mediated function by coupling signaling molecules to the receptor (1). After B cell receptor or CD19 ligation, Tyr531 and Tyr500 of CD19 are progressively phosphorylated. This phosphorylation enables the coupling of PI3 kinase and Src family tyrosine kinase to CD19 and activates the PI3K and Src signaling pathways (2,3). Coligation of B cell receptor and CD19 also promotes Tyr409 phosphorylation in CD19. The phosphorylation at these sites enables its binding to Vav and mediates elevated intracellular calcium response, as well as the JNK pathway (4,5).

$249
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to PE and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: CD161/KLRB1 (Killer cell lectin-like receptor subfamily B member 1, also known as CLEC5B and NKR-P1A) is a type II transmembrane protein that is expressed on the majority of Natural Killer (NK) cells, NK T cells, and some T lymphocytes (1). CD161/KLRB1 is also expressed on Th17 cells, promotes their generation, and modulates their function (2). Engagement with its ligand lectin-like transcript 1 (LLT1) inhibits NK cell function, while LLT1 and CD161/KLRB1 interaction in the presence of a TCR signal enhances IFN-gamma production by T cells (3,4). There are several different CD161 isoforms in rodents and some function as activating receptors as well (5,6).

$239
100 µg
This Cell Signaling Technology antibody is conjugated to violetFluor™ 450 and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: Cluster of Differentiation 4 (CD4) is a glycoprotein composed of an amino-terminal extracellular domain (four domains: D1-D4 with Ig-like structures), a transmembrane part and a short cytoplasmic tail. CD4 is expressed on the surface of T helper cells, regulatory T cells, monocytes, macrophages and dendritic cells, and plays an important role in the development and activation of T cells. On T cells, CD4 is the co-receptor for the T cell receptor (TCR), and these two distinct structures recognize the Antigen–Major Histocompatibility Complex (MHC). Specifically, the D1 domain of CD4 interacts with the β2-domain of the MHC class II molecule. CD4 ensures specificity of the TCR–antigen interaction, prolongs the contact between the T cell and the antigen presenting cell and recruits the tyrosine kinase Lck, which is essential for T cell activation (1).