Recombinant Human TNFα

Recombinant human TNFα is a valuable tool for research due to its wellcharacterized biological activity, versatility across multiple experimental applications, and availability in highly purified forms. Here are the key reasons to incorporate it into your research:

Biological Activity and Functional Versatility

Recombinant human TNFα is a pleiotropic cytokine that plays central roles in inflammation, immune system development, apoptosis, and lipid metabolism. This multifaceted nature makes it applicable across diverse research contexts. The protein can induce fever, trigger apoptotic cell death, inhibit tumorigenesis and viral replication, and act as a potent mediator of acute phase reactions. These properties enable investigation of TNFαinduced signaling pathways and its effects on various cellular processes.

Research Applications

The recombinant protein is optimized for multiple experimental approaches:

• Cell differentiation and maturation studies, including induction of monocytederived dendritic cell maturation
• Cytotoxicity and cell proliferation assays to evaluate TNFα effects on target cells
• Apoptosis assessment and viral protection studies
• Signaling pathway investigation to elucidate TNFαmediated mechanisms
• Bioassays using whole cell systems
• ELISA standards and Western blot controls for quantitative and qualitative analyses

Preclinical and Therapeutic Insights

Recombinant TNFα has demonstrated direct cytostatic and cytotoxic effects on human tumor cells in addition to immunomodulatory effects on neutrophils, macrophages, and T cells. It exhibits antiinfective and metabolic effects both in vitro and in vivo, providing valuable preclinical data for understanding TNFα biology and its therapeutic potential.

Production Quality and Availability

The application of recombinant DNA technology has made large quantities of highly purified TNFα readily available. Modern production systems yield biologically active, validated proteins suitable for rigorous scientific investigation, with options including animalfree formulations for specialized applications.

Yes, recombinant human TNFα can be used as a standard for quantification or calibration in ELISA assays, provided it is properly validated and prepared according to assay requirements.

Key considerations and supporting details:

• Intended Use: Recombinant human TNFα is widely used as a quantitative standard in ELISA assays for measuring TNFα levels in biological samples such as serum, plasma, and cell culture supernatants. Most commercial ELISA kits are designed to recognize both native and recombinant forms of TNFα.

• Preparation and Handling:

  • The recombinant standard should be reconstituted and diluted according to the manufacturer’s or protocol’s instructions to ensure accuracy and reproducibility.
  • It is recommended to use carrier proteins (e.g., BSA) at concentrations of 5–10 mg/mL when preparing standards to prevent adsorption and loss of activity, especially at low concentrations.
  • Standards should be freshly prepared or stored at recommended temperatures (often 70°C for stock solutions) and not reused after dilution to maintain integrity and activity.

• Validation:

  • The recombinant standard must be validated for linearity, accuracy, and specificity within the context of your assay.
  • Ensure that the standard curve generated with recombinant TNFα is linear and covers the expected concentration range of your samples (e.g., 15–2000 pg/mL or as specified by your assay).
  • Confirm that the antibodies used in your ELISA recognize the recombinant form equivalently to the native protein, as most kits are designed for this.

• Matrix Effects:

  • When quantifying TNFα in complex matrices (e.g., serum or plasma), verify that the recombinant standard behaves similarly to endogenous TNFα in your assay system to avoid matrix interference.

• Documentation:

  • Always refer to the specific ELISA kit or assay protocol for instructions regarding the use of recombinant standards, as requirements may vary between kits and platforms.

Summary Table: Use of Recombinant Human TNFα as ELISA Standard

In summary: Recombinant human TNFα is suitable and commonly used as a standard for ELISA quantification, but proper preparation, validation, and adherence to assayspecific protocols are essential for accurate results.

Recombinant Human TNFα has been validated for a wide range of applications in published research, primarily in bioassays, cell signaling studies, immunological assays, and pharmacokinetic analyses.

Key validated applications include:

• Bioassays: TNFα is widely used to stimulate cells in vitro to study inflammatory responses, apoptosis, immune cell activation, and cell signaling pathways. Numerous studies have used recombinant human TNFα to induce cytokine production, assess barrier function in epithelial cells, and model disease states such as sepsis, arthritis, and neuroinflammation.

• Reporter Assays: TNFα activity is commonly measured using luciferase reporter assays in transfected cell lines (e.g., HEK293T), allowing quantification of downstream signaling events.

• ELISA Development and Validation: Recombinant human TNFα serves as a capture antigen in ELISA assays for quantifying antiTNFα therapeutic antibodies (e.g., adalimumab) in biological samples, supporting pharmacokinetic and biocomparability studies.

• Cytotoxicity Assays: TNFα is validated for inducing cytotoxicity in sensitive cell lines (e.g., L929 fibroblasts) to assess cell death mechanisms and screen for inhibitors or protective agents.

• Immunoregulatory and Autoimmune Disease Research: TNFα is used to model autoimmune and inflammatory diseases in vitro, including rheumatoid arthritis, psoriasis, and inflammatory bowel disease, by stimulating relevant cell types and analyzing cytokine profiles and immune cell behavior.

• Cancer Research: Recombinant TNFα is applied in studies of tumor cell apoptosis, antitumor immune responses, and as an adjunct to chemotherapy to enhance drug delivery and efficacy in preclinical models.

• Quality Control and Batch Release: Validated ELISA protocols using recombinant TNFα are employed in drug manufacturing for batch release and quality control of antiTNFα biologics.

• Screening of Inhibitory Molecules: TNFα is used with engineered cell lines to screen for inhibitors, such as monoclonal antibodies or small molecules, that block TNFα signaling.

Sample types validated include whole cells, transduced cells, and biological fluids (e.g., serum for ELISA).

Summary Table of Validated Applications

These applications are supported by peerreviewed publications and technical datasheets, confirming the broad utility and validation of recombinant human TNFα in both basic and translational research contexts.

To reconstitute and prepare Recombinant Human TNFα protein for cell culture experiments, dissolve the lyophilized protein in sterile buffer (typically PBS or distilled water) at a concentration of 0.1–1 mg/mL, ideally with 0.1% carrier protein such as endotoxinfree human or bovine serum albumin (HSA/BSA) to stabilize the protein and minimize adsorption losses.

Detailed protocol:

• Centrifuge the vial briefly before opening to ensure all material is at the bottom.
• Reconstitution buffer: Use sterile 1× PBS (pH 7.2–7.4) or sterile distilled water. For maximum stability and to prevent loss of activity, include at least 0.1% endotoxinfree HSA or BSA as a carrier protein.
• Concentration: Reconstitute to a final concentration of 0.1–1 mg/mL, depending on your experimental requirements.
• Mixing: Gently swirl or tap the vial to dissolve. Avoid vigorous vortexing, which may denature the protein.
• Aliquoting: Divide the reconstituted solution into working aliquots to avoid repeated freezethaw cycles, which can degrade the protein.
• Storage: Store aliquots at ≤ –20°C for longterm use. For shortterm use (up to 1 week), store at 4°C.
• Further dilution: For cell culture, dilute the aliquots to the desired working concentration in cell culture medium or buffer containing carrier protein (e.g., 0.1% BSA or heatinactivated FCS) to maintain stability and minimize adsorption to plasticware.

Key considerations:

• Avoid sodium azide if the protein will be used in functional cell assays, as it is cytotoxic.
• Endotoxin: Ensure the carrier protein and all reagents are endotoxinfree, especially for sensitive cell types.
• Optimal working concentration should be empirically determined for each cell line and application.

Summary of best practices:

• Use sterile technique throughout.
• Include a carrier protein (0.1% BSA or HSA) in all buffers.
• Avoid repeated freezethaw cycles by aliquoting.
• Store at ≤ –20°C for longterm stability.

These steps will help maintain the biological activity and reproducibility of recombinant human TNFα in cell culture experiments.