Assay Kits

Retinol binding protein (RBP) 4 is the only specific transport protein for vitamin A in the circulation whose function is to deliver vitamin to target tissues. In obesity and type 2 diabetes, expression of Glut4 is significantly impaired in adipocytes. Glucose transport via Glut4 is the rate-limiting step for glucose use by muscle and adipose tissue. Adipocyte-specific deletion of Gluts leads to notable elevation of RBP4 causing systemic insulin resistance, and that reduction of RBP4 improves insulin resistance. This identified a novel role of RBP4 in regulating insulin action and RBP4 is recorded as an adipocyte-derived hormone. The RBP4 (human) ELISA Kit is to be used for the in vitro quantitative determination of human RBP4 in biological fluids. This assay is a sandwich ELISA which utilizies a 96-well microtiter plate which was pre-coated with a monoclonal antibody and a purified polyclonal detection antibody. A HRP-conjugated anti-IgG, peroxidase and TMB (3,3’,5,5’-tetramethylbenzidine) is added to generate a color intensity directly proportional to the concentration of RBP4 in the samples. This ELISA is specific for the measurement of natural and recombinant human RBP4. It does not cross-react with mouse RBP4, rat RBP4, human adiponectin, human resistin, human vaspin, human clusterin, human leptin, human IL-33, human GPX3, human progranulin, human FABP4, human ANGPTL3, human ANGPTL4, human ANG1, human ANG2, human Nampt, mouse Nampt. The assay range is 0.39 – 25 ng RBP4/mL and a detection limit of 380 pg/mL (based on adding two standard deviations to the mean value of the (50) zero standards).

Retinol binding protein (RBP) 4 is the only specific transport protein for vitamin A in the circulation whose function is to deliver vitamin to target tissues. In obesity and type 2 diabetes, expression of Glut4 is significantly impaired in adipocytes. Glucose transport via Glut4 is the rate-limiting step for glucose use by muscle and adipose tissue. Adipocyte-specific deletion of Gluts leads to notable elevation of mouse RBP4 causing systemic insulin resistance, and that reduction of RBP4 improves insulin resistance. This identified a novel role of RBP4 in regulating insulin action and RBP4 is recorded as an adipocyte-derived hormone. The RBP4 (mouse/rat) ELISA Kit is to be used for the in vitro quantitative determination of mouse or rat RBP4 in serum, urine and cell culture supernatant. This assay is a sandwich ELISA which utilizies a 96-well microtiter plate which was pre-coated with a monoclonal antibody and a purified polyclonal detection antibody. A HRP-conjugated anti-IgG, peroxidase and TMB (3,3’,5,5’-tetramethylbenzidine) is added to generate a color intensity directly proportional to the concentration of RBP4 in the samples. This ELISA is specific for the measurement of natural and recombinant mouse and rat RBP4. It does not cross-react with human RBP4, mouse adiponectin, mouse resistin, mouse Nampt, rat adiponectin, rat resistin, rat Nampt, mouse RELM-α, mouse RELM-β, human leptin, rat RELM-α, mouse 41BBL, mouse CD137, mouse Tim3, human TNF-α. The assay range is 0.188 – 12 ng RBP4/mL and a detection limit of 60 pg/mL (based on adding two standard deviations to the mean value of the (50) zero standards).

SIRT1 or Sirtuin 1 is a member of the silent information regulator 2 family. SIRT1, an NAD-dependent histone deacetylase can deacetylate histones and a number of nonhistone substrates, including p53. It is predominantly localized in the nucleus of normal cells. In cancer cells however, it is predominantly localized in the cytoplasm. SIRT1 has been shown to regulate a wide range of cellular functions that affect metabolic homeostasis and aging. SIRT1 exerts anti-apoptotic, anti-oxidative, and anti-inflammatory effects against cellular injury, and protects the cells through the regulation of mitochondrial biogenesis, autophagy, and metabolism in response to the cellular energy and redox status. SIRT1 also promotes vasodilation and protects vascular tissues. Activation and inhibition of SIRT1 is being targeted for various diseases. Unlike other known protein deacetylases, which simply hydrolyze acetyl-lysine residues, the sirtuin-mediated deacetylation reaction hydrolyzes acetyl-lysine and NAD. This hydrolysis yields the deacetylated substrate, O-acetyl-ADP-ribose and nicotinamide, itself an inhibitor of sirtuin activity. In SIRT1 Inhibitor/Activator screening Kit, Sirtuin 1 deacetylates the substrate, followed by cleavage of the deacetylated substrate to release the fluorescent group, which is detected fluorometrically at Ex/Em = 400/505 nm. In the presence of SIRT1 inhibitor, deacetylation is impeded, preventing cleavage of the substrate and release of the fluorescent group. The SIRT1 activator enhances SIRT1 activity resulting in a higher fluorescent signal in comparison to the control. This kit provides a rapid, simple, sensitive, and reliable test, which is suitable for high-throughput screening of SIRT1 inhibitors/activators. Inhibitor control (Nicotinamide) is included to compare the efficacy of the test inhibitors.

Sirtuin or Sir2 proteins are a class of proteins that possess either histone deacetylase or mono-ribosyltransferase activity. Sirtuins have been implicated in influencing aging and regulating transcription, apoptosis and stress resistance, as well as energy efficiency and alertness during low-calorie situations. Unlike other known protein deacetylases, which simply hydrolyze acetyl-lysine residues, the sirtuin-mediated deacetylation reaction couples lysine deacetylation to NAD hydrolysis. This hydrolysis yields O-acetyl-ADP-ribose, the deacetylated substrate and nicotinamide, itself an inhibitor of sirtuin activity. Studies suggest that the human sirtuins may function as intracellular regulatory proteins with mono-ADP-ribosyltransferase activity. In Sirtuin inhibitor screening Kit, Sirtuin deacetylates the substrate and then the developer cleaves the deacetylated substrate to release the fluorescent group, which can be detected fluorometrically at Ex/Em = 395/541 nm. In the presence of SIRT inhibitor, the deacetylation will be impeded which prevents the cleavage of the substrate to release the fluorescent group. The kit provides a rapid, simple, sensitive, and reliable test, which is also suitable for high-throughput screening of SIRT2 inhibitors. Inhibitor control (Nicotinamide) is included to compare the efficacy of the test inhibitors.

Sirtuin 1 is the human ortholog for the yeast Sir2 (silent information regulator 2) protein regulating epigenetic gene silencing as a possible antiaging effect. Sirtuin 1 is an NAD(+)-dependent histone deacetylase, which deacetylate lysines 9 and 14 of histone H3 and lysine-16 of histone H4, involved in various cellular functions such as transcription, energy sensing, and differentiation. Sirtuin1 plays an important role in regulating adipogenesis via repression of PPAR and the gluconeogenic/glycolytic pathways in liver in response to fasting signals through the transcriptional coactivator PGC1A deacetylated at specific lysine residues in an NAD(+)-dependent manner. This assay is a sandwich Enzyme Linked-Immunosorbent Assay (ELISA) for quantitative determination of human Sirtuin 1 in cells. A monoclonal antibody specific for Sirtuin 1 has been precoated onto the 96-well microtiter plate. Standards and samples are pipetted into the wells for binding to the coated antibody. After extensive washing to remove unbound compounds, Sirtuin 1 is recognized by the addition of a purified polyclonal antibody specific for Sirtuin 1 (Detection Antibody). After removal of excess polyclonal antibody, HRP conjugated anti-rabbit IgG (Detector) is added. Following a final washing, peroxidase activity is quantified using the substrate 3,3’,5,5’-tetramethylbenzidine (TMB). The intensity of the color reaction is measured at 450 nm after acidification and is directly proportional to the concentration of Sirtuin 1 in the samples. This ELISA is specific for the measurement of natural and recombinant human Sirtuin 1. It does not cross-react with human Sirtuin 2, human Sirtuin 5, human Sirtuin 6, human adiponectin, human resistin, human RBP4, human vaspin, human progranulin, human GPX3, human FTO, human Nampt, human leptin, mouse FTO, mouse Nampt. The assay range is 0.031 – 2 ng Sirtuin 1/mL and a detection limit of 30 pg/mL (based on adding two standard deviations to the mean value of the (50) zero standards).

Signal transducer and transcription activator that mediates cellular responses to interleukins, KITLG/SCF, LEP and other growth factors. Once activated, recruits coactivators, such as NCOA1 or MED1, to the promoter region of the target gene. May mediate cellular responses to activated FGFR1, FGFR2, FGFR3 and FGFR4. Binds to the interleukin-6 (IL-6)-responsive elements identified in the promoters of various acute-phase protein genes. STAT3 ELISA kit is a sandwich ELISA assay for the quantitative measurement of human STAT3 in serum, plasma and cell culture supernatants. The density of color is proportional to the amount of STAT3 captured from the samples.

TGF-β1 is a multifunctional cytokine involved in cell growth, differentiation and inflammatory pathways. TGF-β1 (human) ELISA Kit is based on the standard principle of a sandwich enzyme-linked immunosorbent assay. A mouse monoclonal antibody specific for human TGF-β1 is coated on a 96-well plate. Standards and test samples are added to the wells and TGF-β1 present in a sample is bound by the immobilized antibody. A biotinylated polyclonal antibody from goat specific for TGF-β1 is added subsequently. After washing away the unbound biotinylated antibody with PBS or TBS buffer, avidin-Biotin-Peroxidase Complex is added to the wells. The wells are again washed with PBS or TBS buffer to remove the unbound conjugates. HRP substrate TMB is used to visualize the HRP enzymatic reaction. TMB is catalyzed by HRP to produce a blue product that changes into yellow after adding acidic stop solution. The density of yellow color is proportional to the human TGF-β1 captured onto the plate. This ELISA kit shows <1% cross-reactivity with TGF-β2, TGF-β3 and TGF-β5. Detection Range: 15.6 pg/mL – 1000 pg/mL. Sensitivity: < 1 pg/mL.

TGF-β1 is a multifunctional cytokine involved in cell growth, differentiation and inflammatory pathways. TGF-β1 (mouse) ELISA Kit is based on the standard principle of a sandwich enzyme-linked immunosorbent assay. A rat monoclonal antibody specific for mouse TGF-β1 is coated on a 96-well plate. Standards and test samples are added to the wells and TGF-β1 present in a sample is bound by the immobilized antibody. A biotinylated polyclonal antibody from goat specific for TGF-β1 is added subsequently. After washing away the unbound biotinylated antibody with PBS or TBS buffer, avidin-Biotin-Peroxidase Complex is added to the wells. The wells are again washed with PBS or TBS buffer to remove the unbound conjugates. HRP substrate TMB is used to visualize the HRP enzymatic reaction. TMB is catalyzed by HRP to produce a blue product that changes into yellow after adding acidic stop solution. The density of yellow color is proportional to the mouse TGF-β1 captured onto the plate. This ELISA kit shows <1% cross-reactivity with TGF-β2, TGF-β3 and TGF-β5. Detection Range: 15.6 pg/mL – 1000 pg/mL. Sensitivity: < 2 pg/mL.

TGF-β1 is a multifunctional cytokine involved in cell growth, differentiation and inflammatory pathways. TGF-β1 (rat) ELISA Kit is based on the standard principle of a sandwich enzyme-linked immunosorbent assay. A mouse monoclonal antibody specific for rat TGF-β1 is coated on a 96-well plate. Standards and test samples are added to the wells and TGF-β1 present in a sample is bound by the immobilized antibody. A biotinylated polyclonal antibody from goat specific for TGF-β1 is added subsequently. After washing away the unbound biotinylated antibody with PBS or TBS buffer, avidin-Biotin-Peroxidase Complex is added to the wells. The wells are again washed with PBS or TBS buffer to remove the unbound conjugates. HRP substrate TMB is used to visualize the HRP enzymatic reaction. TMB is catalyzed by HRP to produce a blue product that changes into yellow after adding acidic stop solution. The density of yellow color is proportional to the rat TGF-β1 captured onto the plate. This ELISA kit shows <1% cross-reactivity with TGF-β2, TGF-β3 and TGF-β5. Detection Range: 15.6 pg/mL – 1000 pg/mL. Sensitivity: < 1 pg/mL.

Vitamin D3 (Cholecalciferol) is found in human epidermis and dermis. Human Vit. D3 ELISA Kit is based on the standard principle of a sandwich enzyme-linked immunosorbent assay. Human Vit. D3 antibody is coated on a 96-well plate. Standards and test samples are added to the wells and Vit. D3 present in a sample is bound by the immobilized antibody. An HRP-conjugate reagent is added subsequently. After washing away the unbound antibody/HRP conjugates, HRP substrate TMB is used to visualize the HRP enzymatic reaction. TMB is catalyzed by HRP to produce a blue product that changes into yellow after adding acidic stop solution. The density of yellow color is proportional to the human Vit. D3 captured onto the plate. This ELISA kit shows no species cross-reactivity. Detection Range: 20 – 800 µg/L.

DNA methylation at CpG islands in promoters regulates gene expression. It is a dynamic epigenetic process affected by various genetic and environmental factors. Numerous diseases including cancer have been linked to aberrant global changes in genomic DNA methylation. It is generally thought that global genomic DNA methylation level can be represented by the methylation level at repetitive elements. One example of this includes the repetitive Long Interspersed Nuclear Element-1 (LINE-1), which compromises 17-18% of the human genome and is usually heavily methylated in most normal primary cells. Furthermore, the CpG island methylation level at human ELOVL2 gene promoter has been well-associated with chronological age in various populations, cell types, and tissues. ELOVL2 promoter methylation level is therefore a potential marker for human chronological age.

Accurate and consistent quantification of telomere length is essential in many aspects of cell biology, such as chromosomal instability, DNA repair, senescence, apoptosis, cell dysfunctions, and oncogenesis. This product mainly uses relative quantitative qPCR to directly compare the average telomere length of the sample, that is, the copy number ratio (T/S) of the telomere repeat sequence (Tel) and the genome single copy gene (SCR) copy number (T/S) is used as the telomere relative length. The telomere primer set recognizes and amplifies telomere sequences. The single copy reference (SCR) primer set recognizes and amplifies the 100 bp-long regions on human chromosome 17 and serves as a reference for data normalization.

Telomeres are repetitive nucleotide sequences located at the ends of chromosomes, and their primary role is to safeguard chromosomes from degradation and the loss of genetic information during cell division. In normal diploid cells, telomeres progressively shorten with each cell cycle. As a result, telomere length gradually decreases over time, and it has been associated with the potential to predict an organism's lifespan. The shortening of telomeres has detrimental effects on various aspects of health and is linked to numerous health conditions, including aging and cancer. Accurate and consistent quantification of telomere length is crucial in several areas of cell biology, including the study of chromosomal stability, DNA repair mechanisms, senescence (cellular aging), apoptosis (programmed cell death), cell dysfunctions, and the development of cancer. Understanding and quantifying telomere length provides valuable insights into these biological processes, contributing to our knowledge of how cells function and age, as well as their involvement in the onset and progression of diseases such as cancer.

Telomeres are repetitive nucleotide sequences found at the ends of chromosomes, and their primary function is to protect chromosomes from degradation and the loss of genetic information during cell division. Telomerase is a specialized enzyme containing RNA that plays a crucial role in synthesizing the telomere repeat sequence, which is located at the 3' end of telomeres. In normal diploid cells, telomerase activity is typically absent, leading to the gradual shortening of telomeres with each cell division. This shortening of telomeres is associated with cellular aging and eventual cell death. However, in certain cell types, such as embryonic stem cells and many cancer cells, telomerase is activated. This activation allows these cells to maintain telomere length and achieve a form of cellular immortality, as they can continue to divide without experiencing the usual telomere-related limitations. Quantitatively measuring telomerase activity is a crucial aspect of cell biology, as it has implications for various processes, including stem cell biology and the development of cancer. It helps researchers understand the mechanisms behind cellular immortality and can provide insights into oncogenesis and stemness.

Mitochondrial DNA (mtDNA) is circular, multicopy genome DNA located in mitochondrion, a cellular organelle that plays a key role in energy production of the cell. The capacity for energy production in a cell depends on both mtDNA integrity and copy number. Substantial evidence suggests that alterations in mtDNA copy number have been correlated with aging and various age-related disorders, such as cancer, diabetes and neurodegenerative diseases.

Mitochondrial DNA (mtDNA) is circular, multicopy genome DNA located in mitochondrion, a cellular organelle that plays a key role in the energy production. The capacity for energy production in a cell depends on both mtDNA integrity and copy number. Substantial evidence suggests that alterations in mtDNA copy number has been correlated with aging and various age-related disorders, such as cancer, diabetes and neurodegenerative diseases.

This Assay Kit is specifically designed for the concurrent quantification of two important parameters, the average telomere length and the mitochondrial DNA (mtDNA) copy number, within a human cell population using quantitative polymerase chain reaction (qPCR) technology. Here's how it works: 1. Telomere Primer Set, This set of primers is designed to recognize and amplify telomere sequences within the cell population. 2. mtDNA Primer Set, This primer sets targets and amplifies one of the most highly conserved regions on human mtDNA. Importantly, it will not amplify any unintended sequences from nuclear genomic DNA. 3. Single Copy Reference (SCR) Primer Set, The SCR primer set is designed to recognize and amplify a specific 100 bp-long region located on human chromosome 17. It serves as a reference point for data normalization, enabling accurate comparisons between samples. To determine the telomere length and mtDNA copy number of target samples, a reference genomic DNA sample with known telomere length and mtDNA copy number is used as a benchmark. By comparing the qPCR results of the target samples to those of the reference, you can calculate the telomere length and mtDNA copy number for the samples of interest. This assay provides valuable information about cellular aging (telomere length) and mitochondrial function (mtDNA copy number) within the tested cell population, aiding in a wide range of research applications.

DNA methylation at CpG islands in promoters regulates gene expression. It is a dynamic epigenetic process affected by various genetic and environmental factors including aging. The CpG island methylation level at human ELOVL2 gene promoter has been well-associated with chronological age in various populations, cell types, and tissues. ELOVL2 promoter methylation level is therefore a potential marker for human chronological age. ScienCell's Human Age-associated ELOVL2 Promoter Methylation Quantification qPCR Assay Kit (HAEPM) is designed to quantify the level of human ELOVL2 promoter methylation. The reference DNA sample consists of a 1:1 ratio of methylated ELOVL2 promoter copies to non-methylated ELOVL2 promotor copies (both copies represent bisulfite converted promoter sequences), and serves as a reference for calculating the ratio of methylated to non-methylated ELOVL2 promotor of target samples. The carefully designed primers ensure: (i) high efficiency for trustworthy quantification; and (ii) negligible non-specific amplification. Each primer set has been validated by qPCR with melt curve analysis and gel electrophoresis for amplification specificity and by template serial dilution for amplification efficiency.

Telomeres are repetitive nucleotide sequences located at the ends of chromosomes, and their primary role is to safeguard chromosomes from degradation and the loss of genetic information during cell division. In normal diploid cells, telomeres progressively shorten with each cell cycle. As a result, telomere length gradually decreases over time, and it has been associated with the potential to predict an organism's lifespan. The shortening of telomeres has detrimental effects on various aspects of health and is linked to numerous health conditions, including aging and cancer. Accurate and consistent quantification of telomere length is crucial in several areas of cell biology, including the study of chromosomal stability, DNA repair mechanisms, senescence (cellular aging), apoptosis (programmed cell death), cell dysfunctions, and the development of cancer. Understanding and quantifying telomere length provides valuable insights into these biological processes, contributing to our knowledge of how cells function and age, as well as their involvement in the onset and progression of diseases such as cancer.

Telomeres are repetitive nucleotide sequences located at the ends of chromosomes, and their primary role is to safeguard chromosomes from degradation and the loss of genetic information during cell division. In normal diploid cells, telomeres progressively shorten with each cell cycle. As a result, telomere length gradually decreases over time, and it has been associated with the potential to predict an organism's lifespan. The shortening of telomeres has detrimental effects on various aspects of health and is linked to numerous health conditions, including aging and cancer. Accurate and consistent quantification of telomere length is crucial in several areas of cell biology, including the study of chromosomal stability, DNA repair mechanisms, senescence (cellular aging), apoptosis (programmed cell death), cell dysfunctions, and the development of cancer. Understanding and quantifying telomere length provides valuable insights into these biological processes, contributing to our knowledge of how cells function and age, as well as their involvement in the onset and progression of diseases such as cancer.