Human 4-1BBL/TNFSF9 Protein (N-His)

Product Details


ApplicationELISA, BLI
FormatLiquid, Purified
Expression HostCHO
Target NameTNFSF9, 4-1BB Ligand, CD137L
SpeciesHuman
Accession NumberP41273
SourcesRecombinant Human TNFSF15 (Leu72-Leu251) with N-terminus His tag is expressed in CHO cells.
Molecular WeightThis protein has a predicted molecular weight of 21.6 kDa. Under DTT-reducing conditions, the protein migrates at approximately 23 kDa on SDS-PAGE.
Affinity TagN-His
Purity>95% based on SDS-PAGE under reducing condition
Regulatory StatusRUO
Formulation1xPBS buffer, pH7.4, 0.22 µm filtered
Endotoxin levelLess than 0.1 EU/µg protein as determined by the LAL method
Protein Concentration25µg size is bottled at 0.2mg/mL concentration. 100 µg size is supplied at a lot-specific concentration.
Storage and HandlingBriefly centrifuge the vial upon receipt. An unopened vial can be stored at 4°C for up to 2 weeks, or at -20°C or below for up to six months. The protein may be further diluted to 0.1 mg/mL using 0.22 µm-filtered PBS buffer (pH 7.4). For long-term storage, the diluted stock solution should be aliquoted and stored at ≤ –70°C to minimize freeze-thaw cycles. If additional dilution is required, carrier proteins such as FBS or BSA should be added to maintain protein stability.
Research AreasCo-stimulation, Dendritic cells, Monocytes, Macrophages, B cells, Cancer Marker, Inflammation

Background Information


4-1BB ligand (4-1BBL), also known as CD137L and encoded by the TNFSF9 gene, is a costimulatory molecule belonging to the tumor necrosis factor (TNF) superfamily. It is primarily expressed on activated antigen-presenting cells (APCs), including dendritic cells, macrophages, and B cells, as well as on some non-hematopoietic cells under inflammatory conditions. 4-1BBL plays a central role in enhancing cellular immune responses by engaging its receptor, 4-1BB (CD137), which is expressed on activated CD8⁺ and CD4⁺ T cells, natural killer (NK) cells, and certain other immune subsets.

Structurally, 4-1BBL is a type II transmembrane protein characterized by a short N-terminal cytoplasmic region, a single transmembrane domain, and a C-terminal extracellular TNF homology domain. Like other TNF superfamily ligands, it forms homotrimers on the cell surface, a configuration necessary for efficient receptor clustering and signaling. Soluble forms of 4-1BBL have also been described, although membrane-bound trimeric forms are generally more potent in mediating biological activity.

The primary ligand for 4-1BBL is 4-1BB (CD137), a member of the TNF receptor superfamily. Engagement of 4-1BB by 4-1BBL recruits TNF receptor–associated factors (TRAFs) to the receptor cytoplasmic tail, activating NF-κB, MAPK, and PI3K–Akt signaling pathways. This signaling enhances T cell proliferation, cytokine production (notably IFN-γ), cytotoxic function, and survival, particularly in CD8⁺ T cells. 4-1BBL can also transmit “reverse signaling” into APCs, modulating their activation and cytokine profiles.

Dysregulated 4-1BB/4-1BBL signaling has implications in cancer, chronic infection, and autoimmune disease. In oncology, 4-1BB signaling supports antitumor cytotoxic T cell responses, making it an attractive immunotherapeutic target. However, excessive activation can contribute to immune-mediated tissue damage or autoimmunity.

Therapeutically, strategies targeting the 4-1BB axis are being actively developed. Agonistic antibodies to 4-1BB aim to enhance antitumor immunity, often in combination with checkpoint inhibitors. Engineered 4-1BBL constructs are also incorporated into cancer vaccines and chimeric antigen receptor (CAR) T cell designs to improve persistence and function. By amplifying cytotoxic immune responses, 4-1BBL-based approaches represent a promising avenue in cancer immunotherapy and immune modulation.

Data Sheets


Human 4-1BBL/TNFSF9 Protein (N-His) TDS

Related Protocols


Direct ELISA Protocol

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Frequently Asked Questions


Why are Recombinant Proteins expressed with epitope tags?
The majority of InnoCyto's recombinantly expressed proteins are engineered with a short, well-characterized peptide sequence (e.g., His-tag, Fc-tag, Flag-tag, or similar) fused to the protein of interest. The tag enables reliable detection, purification, or immobilization of the protein using commercially available anti-tag antibodies or affinity resins, without needing a custom antibody against the native protein.

What types of tagged proteins are best for my application?
Common tag options include His-tag (for affinity purification via Ni-NTA/IMAC and detection via anti-His antibodies), Fc-tag (for use in binding assays, ELISA capture, and dimerization studies), and Flag-tag (for high-specificity detection and immunoprecipitation). Tag choice should be based on your intended workflow — purification-focused work often favors His-tag, while functional binding or capture-based assays often benefit from Fc-tag.

Does the tag affect the protein's biological activity or binding function?
Tag placement (N-terminal vs. C-terminal) and type are selected during design to minimize interference with the protein's native folding and functional binding site, and each tagged protein is validated for activity in relevant binding or functional assays. Product pages indicate the tag location and confirm the functional validation performed for that specific protein.

Have a product or application question? Consult our FAQs or contact us.