Recombinant Human TGF-β1

Recombinant Human TGF-β1 is a highly valuable tool for research applications due to its well-characterized biological activity and versatility in studying cellular processes. Here are the key reasons to use Recombinant Human TGF-β1 in your research:

1. Consistent and Reproducible Supply

Recombinant TGF-β1 is produced using genetic engineering, ensuring a consistent and reproducible source of biologically active protein. This eliminates variability associated with isolating TGF-β1 from natural sources, which can be limited and inconsistent.

2. High Purity and Quality

Recombinant TGF-β1 is typically purified to high levels (>95% purity), with minimal contamination from endotoxins or other proteins. This ensures reliable and specific results in sensitive assays and cell culture experiments.

3. Broad Biological Functions

TGF-β1 regulates a wide range of cellular processes, including:

• Cell proliferation and differentiation
• Apoptosis (programmed cell death)
• Wound healing and tissue repair
• Immune modulation (e.g., Treg and Th17 cell differentiation)
• Extracellular matrix production
• Angiogenesis (formation of new blood vessels)

These functions make it essential for studies in immunology, regenerative medicine, cancer biology, and developmental biology.

4. Applications in Stem Cell and Tissue Engineering

Recombinant TGF-β1 is widely used for:

• Culturing and differentiating embryonic and induced pluripotent stem cells
• Promoting chondrogenesis (cartilage formation)
• Supporting vasculogenesis and angiogenesis in tissue engineering models

5. Disease Modeling and Therapeutic Research

TGF-β1 signaling is implicated in various diseases, including:

• Fibrotic disorders (e.g., pulmonary and liver fibrosis)
• Cancer (tumor progression and immune evasion)
• Autoimmune diseases

Recombinant TGF-β1 allows researchers to model these conditions and test potential therapeutic interventions.

6. Functional Assays and Screening

Recombinant TGF-β1 is used as a positive control in:

• TGF-β signaling assays
• Screening for inhibitors or modulators of TGF-β activity (e.g., antibodies, small molecules)
• Validation of engineered TGF-β proteins

7. Supports Diverse Experimental Models

It is compatible with a wide range of experimental systems, including:

• In vitro cell culture (primary cells, cell lines)
• In vivo animal models
• High-throughput screening platforms

8. Facilitates Mechanistic Studies

Using recombinant TGF-β1 enables precise manipulation of TGF-β signaling pathways, allowing researchers to dissect molecular mechanisms and identify downstream effectors.

In summary, Recombinant Human TGF-β1 provides a reliable, high-quality, and versatile reagent for investigating the multifaceted roles of TGF-β1 in health and disease, supporting a broad spectrum of research applications from basic science to translational studies.

Yes, recombinant human TGF-β1 is commonly used as a standard for quantification or calibration in ELISA assays designed to measure TGF-β1. This practice is well-established in both commercial ELISA kits and custom assay protocols.

Supporting details:

• Recombinant TGF-β1 as Standard: Multiple ELISA kits specify the use of recombinant human TGF-β1 as the standard for generating calibration curves, enabling accurate quantification of TGF-β1 in biological samples. The recombinant protein is typically supplied in a lyophilized form and reconstituted according to the kit or protocol instructions.

• Assay Compatibility: Recombinant TGF-β1 is structurally and functionally similar to the native protein found in human samples. Because TGF-β1 is not glycosylated, recombinant and natural forms are generally quantitated equivalently in sandwich ELISA formats.

• Sample Types: ELISA kits using recombinant TGF-β1 as a standard are validated for a variety of sample types, including serum, plasma, cell culture supernatants, and urine.

• Best Practices:

  • Use the recommended diluent and reconstitution procedure for the standard, as specified by your ELISA protocol or kit, to ensure consistency and accuracy.
  • Prepare a standard curve with serial dilutions of recombinant TGF-β1 to calibrate the assay and quantify unknown samples.
  • Confirm that your assay detects the active or total form of TGF-β1 as required by your experimental design.

• Limitations: The recombinant standard is for research use only and not for diagnostic procedures. Do not mix standards or reagents from different kits or lots, as this may affect assay performance.

Summary Table: Recombinant Human TGF-β1 as ELISA Standard

In conclusion, you can use recombinant human TGF-β1 as a standard for quantification or calibration in your ELISA assays, provided you follow the recommended protocols for reconstitution, dilution, and assay setup.

Recombinant Human TGF-β1 has been validated for a wide range of applications in published research, primarily in cellular and molecular biology, immunology, tissue engineering, and disease modeling.

Key validated applications include:

• Cellular assays and bioassays: Used to study cell proliferation, differentiation, apoptosis, migration, and epithelial-mesenchymal transition (EMT) in various cell types, including fibroblasts, immune cells, and stem cells.
• Immunology research: Induction of regulatory T cells (Tregs), modulation of Th17/Treg balance, and investigation of immune cell differentiation and function.
• Fibrosis and tissue remodeling models: Induction of fibrotic responses in hepatic stellate cells, renal cells, and cardiac fibroblasts to model tissue fibrosis and wound healing.
• Cancer biology: Studying tumor microenvironment modulation, cancer cell EMT, metastasis, and immune evasion mechanisms.
• Stem cell culture and differentiation: Maintenance and differentiation of pluripotent stem cells and mesenchymal stem cells, as well as osteoblastic and odontoblastic differentiation.
• Screening assays: Used as a positive control or stimulant in screening for inhibitors or antibodies targeting TGF-β signaling, including neutralization and blocking assays.
• Western blot and ELISA standards: Validated as a standard for quantification and detection of TGF-β1 in immunoassays.
• Flow cytometry: Used to assess cellular responses and phenotypic changes following TGF-β1 stimulation.

Representative published research applications:

• Bioassays: Induction of myofibroblast phenotype, macrophage polarization, and modulation of immune cell memory.
• Functional studies: Inhibition of IL-4-induced proliferation in mouse HT-2 cells, a classic assay for TGF-β1 bioactivity.
• Disease modeling: Used in vitro to mimic pathological conditions such as fibrosis, cancer progression, and immune dysregulation.

Summary Table of Validated Applications

These applications are supported by both product validation data and numerous peer-reviewed studies, confirming the utility of recombinant human TGF-β1 in diverse experimental systems.

Reconstitution Protocols

Recombinant human TGF-β1 is supplied as a lyophilized powder and requires careful reconstitution due to its extreme hydrophobicity and tendency to adhere to surfaces. The specific reconstitution approach depends on your vial size and intended application.

For standard vials (2 μg): Reconstitute at 20 μg/mL in sterile 4 mM HCl containing 1 mg/mL human or bovine serum albumin.

For larger vials (10 μg or greater): Reconstitute at 100 μg/mL in sterile 4 mM HCl containing 1 mg/mL human or bovine serum albumin.

For carrier-free formulations: Reconstitute 2 μg vials at 20 μg/mL in sterile 4 mM HCl containing at least 0.1% human or bovine serum albumin, and 10 μg or larger vials at 100 μg/mL in sterile 4 mM HCl.

Reconstitution Technique

Proper handling during reconstitution is critical for protein recovery. Do not vortex the vial, as this can denature the protein. Instead, briefly centrifuge the vial before opening, then gently swirl or tap the vial to mix. The protein may appear as a film at the bottom of the vial during reconstitution—gentle mixing will help dissolve it.

Preparation of Working Solutions

After initial reconstitution, prepare further dilutions in buffer containing a carrier protein such as 0.1% bovine serum albumin (BSA) or human serum albumin (HSA) in phosphate-buffered saline. For bioassay applications, stock solutions can be prepared at 50–100 μg/mL with 0.2–1% BSA or HSA added as needed.

Alternatively, some pre-reconstituted formulations are available that are precisely reconstituted to 0.1 mg/mL in 100 mM acetic acid, requiring no additional preparation and improving experimental reproducibility.

Storage and Stability

Lyophilized protein: Store at −20°C to −80°C until the expiry date, or at room temperature for up to 2 weeks.

Reconstituted protein: Store at −20°C to −80°C for up to 6 months, or at 4°C for up to 1 week. Aliquots can also be stored between 2°C and 8°C for up to one week.

Freeze-thaw cycles: Avoid repeated freeze-thaw cycles when possible. However, studies show that recombinant TGF-β1 can withstand up to four freeze-thaw cycles without significant loss of activity, and can remain stable at room temperature for one week.

Key Considerations for Cell Culture

The inclusion of carrier proteins (BSA or HSA) is essential for maintaining protein stability and preventing surface adhesion during storage and handling. The acidic pH (4 mM HCl or citric acid) helps maintain protein solubility and activity. When working with carrier-free formulations, ensure adequate carrier protein is present in your working solutions to prevent protein loss to plastic surfaces during cell culture experiments.