TGF-β1(Transforming Growth Factor Beta 1) ELISA Kit (E-EL-0162)

Q1:Why tissue samples do not need to be activated when TGF- beta (transforming growth factor - beta) was detected;

Since the antibodies in the kit recognize activated TGF-β, and TGF-β is a disulfide bond linked by two identical or similar 12.5kDa subunits of molecular weight. The study of human TGF-β cDNA sequence showed that the 112 amino acid residues of the monomer TGF-β were cleaved from the carboxyl terminal by a precursor molecule (per-pro-TGF-β) containing 400 amino acid residues. The N-terminal of per-pro-TGF-β contains a signal peptide, which is cleaved before secretion to become an inactive polypeptide chain precursor (pro-TGF-β). The n-terminal part of the amino acid residue is removed by changing the ionic strength, acidification or protease hydrolysis, and the remaining carboxyl terminal part forms an active TGF-β. A variety of cells in the body can secrete TGF-β in an inactive state. In vitro, the inactive TGF-β, also known as latency associated peptide (LAP), can be activated by acidification. In vivo, the acidic environment can be present near fractures and healing wounds, and the cleavage of the protein itself can cause the TGF-β complex to become activated TGF-β. In general, tissues with active cell differentiation often contain high levels of TGF-β, such as osteoblasts, kidney, bone marrow, and fetal liver hematopoietic cells. Therefore, no additional activation processing is required for tissue sample testing.

Q2:Why is your TGF-β1 kit is universal ELISA kit? Other companies usually provide separate kits for different species. What's the difference?

TGF-β1 exhibits high sequence conservation, and its structure varies minimally among different species. Therefore, our kit can achieve universal detection.

Q3:Must I adhere to the volume specified in the manual during sample activation for TGF-β1 detection in activated samples?

As long as the samples and reagents used during the activation step are consistent with the proportions in the manual, it should fine.

Q4:Does this kit require sample activation before testing? What forms are detected for sample activation and sample inactivation respectively?

TGF-β1 is usually present in an inactive form in biological samples and must be activated before TGF-β1 activity can be detected. The detection of serum, plasma, cell supernatant and other secretory samples requires activation treatment. Intracellular samples such as tissue homogenate supernatant can be detected without activation.

Q5:Why is it necessary to add a protease inhibitor in tissue sample preparation during an Elisa experiment? Will it affect the detection significantly if there is no protease inhibitor?

Tissue samples may contain endogenous or exogenous proteases during processing, leading to degradation of extracted proteins. Therefore, it's necessary to add protease inhibitors during processing to ensure the integrity of target proteins. If customers can keep samples cold and handle them quickly during processing, omitting the protease inhibitor may not have a significant effect. After preparation, samples should be tested promptly or immediately aliquoted and frozen at -20°C or -80°C.

Q6:Which variant of the spike protein does this kit detect? Do you have a kit specific to detect the spike protein for the omicron variant?

This kit is designed for the original strain of the new crown virus, and the omicron variant has not been verified. However, we have verified 26 recombinant variants of the SARS-CoV-2 spike protein through the kit. For more information, customers can refer to the kit instructions (https://file.elabscience.com/Manual/covid_19/E-EL-E605 .pdf).

Q7:What is the range of enzyme activity of your IL-2 freeze-dried powder

Currently our freeze-dried powder is a concentration unit with no information on the activity unit for the time being.

Q8:What is the principle of adding stop solution to stop color reaction in ELISA experiment?

On the one hand, the activity of HRP enzyme is destroyed and the catalytic function of HRP enzyme is lost. On the other hand, the final color changes due to a change in pH.

Q9:The absorbance of the cell supernatant is less than that of the sample diluent alone, so how to concentrate the sample?

The amount of medium can be reduced for subsequent drug administration and modeling.

Q10:My sample volume is small. Can I reduce some reagents proportionally?

No, the detection system of our kits requires strict adherence to the specified sample volume to ensure accurate detection. If the sample volume is insufficient, consider diluting appropriately, but first conduct a pre-experiment to confirm the suitable dilution factor.