Transfluor Technology

Cell-Based Fluorescence Technology for Known and Orphan GPCRs

• Evaluation Kit
• Works with all GPCRs (known, orphan, Gi, Gs, Go, Gq)
• Single read-out for all GPCRs (Gi, Gs, Go, Gq)
• No GPCR labeling or tagging
• Requires no prior knowledge of interacting G-protein
• Eliminates the need for multiple GPCR assays
• Ideal for high content screening (HCS) analysis
• Validated in over 100 GPCRs (from all classes)
• Compatible with most commercially available HCS instruments

Transfluor is a cell-based fluorescence assay used to screen for G-protein-coupled receptors (GPCRs) ligands and other potential drugs that regulate GPCRs. This patented technology provides a powerful functional assay for detecting a compound's activity against known and/or orphan GPCR targets. Transfluor is optimized for HCS; secondary screening and lead optimization.

The technology is based on the discovery that, upon activation by ligand binding, virtually all GPCRs rapidly undergo deactivation or “desensitization” by a common pathway. An early step in this pathway is the binding of the cytoplasmic protein, beta-arrestin, to the activated receptor. Beta-arresting binding deactivates the GPCR signalling and begins the translocation of the receptor into the cell where the ligand is removed and the receptor is recycled back to the cell membrane.

		Figure 1. Left: unstimulated cells. Activation of the receptor induces, within seconds, a mass movement of the fluorescence to the cell membrane (pits, center), and within minutes to endocytic vesicles (right).

By attaching a fluorescent label to beta-arrestin, the location of the receptor-arrestin complex may be monitored. Since desensitization only occurs with an activated receptor, monitoring beta-arrestin translocation and subsequent receptor recycling provides a method to detect the activation of any GPCR.

Using cell lines genetically engineered to express both the labeled beta-arrestin and the GPCR of interest, the Transfluor technology can be used to screen for natural or synthetic ligands, including agonists or antagonists. Activation of the receptor induces a mass movement of the fluorescence to the cell membrane (pits) within seconds, and to endocytic vesicles within minutes.

Transfluor has been validated as a "gold-standard" HCS assay by many pharmaceutical and biotechnology companies and is considered an integral part of their drug discovery process.

Transfluor has been successfully validated on over 100 GPCRs and works across all GPCR classes (Class I, II, III), regardless of interacting G-protein (Gs, Gi/o and Gq/11).

		Figure 2. Transfluor utilizes the redistribution of arrestin-GFP to monitor GPCR activation and inactivation.

Orphan GPCRs

Transfluor technology requires no prior knowledge of the interacting G-protein. This important feature of Transfluor makes it ideally suited for screening orphan GPCRs (oGPCR). The Ligand Independent Translocation (LITe™) assay is an agonist-independent assay used to verify the translocation of beta-arrestin-GFP in orphan GPCRs.

Transfluor Evaluation Kit

The Transfluor Evaluation Kit enables use of the technology for a limited, one-time, six month evaluation period.  The kit provides all the necessary tools for evaluating the technology with the user’s own instrumentation and GPCRs. This allows users to become comfortable with the technology, before proceeding to a tiered licensing option; one that meets the user’s specific needs.

Transfluor Evaluation Kit Components

• U-2 OS β-arrestin2-GFP cells (Parental cell line, to assist with determination of the Transfluor response to end-users choice of GPCR)
• Transfluor Demo Plate (Imaging  grade  plate with fixed cells to assist with instrument validation, and image acquisition and analysis)
• Limited Label License
• Transfluor Evaluation Kit  Product Insert
• U-2 OS β-arrestin2-GFP cells Product Insert
• Transfluor Quick Start Protocol
• Transfluor User’s Guide (complete with protocols and troubleshooting guidelines)

Tiered Licensing Options

• Transfluor Assay Research Site License
• Transfluor Assay Research Global License
• Transfluor Screening Site License
• Transfluor Assay Research and Screening Site License

Two additional third-party licenses are required to run the Transfluor assay: a GFP license (MDC recommends the Prolume Renilla reniformis (Rr) GFP license) and BioImage's fluorescence redistribution license. Terms are as follows:

• Prolume license is renewable on an annual basis for a nominal fee.
• Biomage license is a one-time fee.
• Prolume and Bioimage licenses both provide worldwide coverage.

To streamline your process, you can obtain these licenses directly from MDC. Alternatively, you can also obtain them directly from Prolume and Bioimage.

Please contact your local sales representative for detailed information regarding these licenses. In conjunction with the Transfluor license, MDC also offers a stably transfected GFP beta-arrestin starter cell line and relevant plasmids.

Ordering Information

Purchase of these Transfluor products requires a prior execution of the Transfluor License agreement and the BioImage license. If ordering the GFP cell line or plasmid, a Prolume license is also required for purchase.