Recombinant Human GDNF

Recombinant Human GDNF is widely used in research applications due to its potent neurotrophic effects, especially for promoting the survival, differentiation, and maintenance of various neuronal populations, most notably midbrain dopaminergic neurons.

Key scientific reasons to use recombinant human GDNF include:

• Neuronal Survival and Differentiation: GDNF is essential for the survival and morphological differentiation of midbrain dopaminergic neurons, which are critical in studies of neurodegenerative diseases such as Parkinson’s disease. It also supports motoneurons and peripheral neurons, including sympathetic, parasympathetic, sensory, and enteric neurons.

• Neuroprotection: GDNF protects neurons from toxic damage and apoptosis, making it valuable for modeling neurodegeneration and testing neuroprotective strategies. It upregulates anti-apoptotic proteins (e.g., Bcl-2, Bcl-X) via PI3K signaling and promotes the dopaminergic phenotype by increasing transcription factors like Nurr1 and Pitx3.

• Disease Modeling and Regenerative Medicine: Recombinant human GDNF is used in cell culture and animal models to study Parkinson’s disease, amyotrophic lateral sclerosis (ALS), and other neurodegenerative disorders. It has been tested in clinical trials for Parkinson’s disease and is under investigation for age-related neurodegenerative diseases.

• Stem Cell and Tissue Engineering Applications: GDNF enhances the differentiation and survival of stem cell-derived neurons, supporting neural transplantation and tissue engineering approaches. It is used to functionalize hydrogels and extracellular matrices to improve the maturation and integration of transplanted neural cells.

• Signaling Pathway Analysis: GDNF is a tool for studying apoptosis, cell survival, and signaling pathways in neuronal cell culture systems.

• Non-Neuronal Roles: Beyond the nervous system, GDNF acts as a morphogen in kidney development and regulates spermatogonial differentiation, broadening its utility in developmental biology.

Typical research applications include:

• Neuronal cell culture for survival and differentiation assays
• Neurodegeneration and neuroprotection studies
• Stem cell differentiation protocols
• Tissue engineering and transplantation models
• Analysis of signaling pathways involved in cell survival and apoptosis

Using recombinant human GDNF ensures reproducibility, defined activity, and compatibility with human cell systems, which are critical for translational research and therapeutic development.

Yes, recombinant human GDNF can be used as a standard for quantification and calibration in ELISA assays, but the suitability depends on the specific formulation and your experimental requirements.

Formulation Considerations

BSA-containing versus carrier-free formulations play a critical role in determining appropriate use. The BSA-formulated recombinant GDNF is specifically recommended for use as an ELISA standard. In contrast, carrier-free formulations are recommended for applications where the presence of BSA could interfere with your assay.

ELISA Calibration Standards

Recombinant human GDNF serves as the calibration standard in commercial ELISA kits. These kits are calibrated against highly purified recombinant human GDNF produced through standard expression systems. The recombinant protein standards demonstrate excellent performance characteristics: they produce linear dose-response curves that parallel results obtained with naturally occurring human GDNF, indicating that the kits can accurately determine relative mass values for natural GDNF.

Binding Characteristics

The recombinant GDNF exhibits strong binding affinity to its receptor. When immobilized at 1 µg/mL, recombinant human GDNF can bind with an apparent Kd<1 nM to the GFR alpha-1/GDNF receptor alpha-1 Fc chimera, demonstrating high-affinity interactions suitable for quantitative applications.

Important Limitation

However, there is a critical caveat: ELISA standard recombinant proteins are not recommended for bioassay usage, as they are not tested for these applications. If you intend to use the GDNF for functional bioassays rather than purely quantitative ELISA calibration, you should select a formulation specifically validated for bioassay applications.

For straightforward ELISA quantification and calibration purposes, the BSA-formulated recombinant GDNF is an appropriate choice, provided you verify that the formulation is compatible with your specific assay protocol.

Recombinant human GDNF has been validated for several key applications in published research:

Primary Research Applications

Bioassay and Functional Studies

Recombinant human GDNF is extensively used in bioassay applications to assess biological activity and protein function. The protein demonstrates measurable biological activity, typically reported at 4 U/mg, enabling quantitative evaluation of its effects on target cells.

Neuronal Cell Culture and Differentiation

GDNF serves as a critical survival and differentiation factor in neuronal cell culture systems. It promotes growth and differentiation of neurons and synapses, making it particularly valuable for studies involving dopaminergic neuron development and maintenance. The protein has been specifically validated for use with induced pluripotent stem cell (iPSC)-derived neurons and other neuronal culture models.

Disease Modeling and Neuroprotection Studies

Published research has employed recombinant human GDNF in multiple neurodegenerative disease models, including studies on Parkinson's disease, amyotrophic lateral sclerosis (ALS), and frontotemporal dementia (FTD). The protein is used to model ferroptosis in dopaminergic neurons, investigate mitochondrial dysfunction in ALS, and evaluate neuroprotective mechanisms in various neurological conditions.

Signaling Pathway Analysis

GDNF has been validated for analyzing apoptosis and intracellular signaling pathways, allowing researchers to elucidate the molecular mechanisms underlying neuronal survival and death processes.

Western Blot Control and Immunoassay

The protein serves as a validated control for Western blot applications and functions as an immunoassay standard in quantitative protein detection assays.

These applications collectively demonstrate GDNF's utility as a research tool for understanding neuronal biology, disease mechanisms, and potential therapeutic interventions in neurodegenerative disorders.

To reconstitute and prepare Recombinant Human GDNF (Glial Cell Line-Derived Neurotrophic Factor) protein for cell culture experiments, follow these general best practices based on manufacturer guidelines and scientific protocols:

1. Reconstitution

• Centrifuge the vial briefly before opening to ensure all lyophilized powder is at the bottom.
• Reconstitute with sterile, distilled water or sterile PBS (phosphate-buffered saline), depending on the product formulation:
  • Typical final concentration: 0.1–1.0 mg/mL (most commonly 0.1–0.5 mg/mL).
  • For carrier-free versions, use sterile distilled water.
  • For formulations containing a carrier protein (e.g., BSA), reconstitute in sterile PBS.
• Gently pipette the solution down the sides of the vial to avoid foaming.
• Do not vortex; allow several minutes for complete dissolution by gentle swirling or inversion.

2. Aliquoting and Storage

• Aliquot the reconstituted stock solution into small volumes to avoid repeated freeze-thaw cycles.
• Store aliquots at –80°C (preferred) or –20°C for short-term use.
• Avoid repeated freeze-thaw cycles to maintain protein stability and activity.

3. Dilution for Cell Culture

• Dilute the stock solution in cell culture medium or an appropriate buffer (e.g., PBS with 0.1% BSA) to the desired working concentration.
• Typical working concentrations for cell culture range from 2–12 ng/mL, depending on the cell type and experimental design.
• Prepare dilutions fresh before use when possible.

4. Additional Tips

• Bring all reagents to room temperature before use.
• Use low-protein-binding tubes to minimize protein loss.
• Filter-sterilize the solution if required for sterile cell culture applications.

Summary Protocol

1. Centrifuge vial briefly.
2. Reconstitute with sterile water or PBS to 0.1–0.5 mg/mL.
3. Gently mix; do not vortex.
4. Aliquot and store at –80°C.
5. Dilute to working concentration in culture medium before use.

Always refer to the specific product datasheet for any unique requirements or recommendations.