30 April 2019
Thanks for posting your question. Here at Promega we have thought this could be an interesting application for NanoBiT, but so far have looked at it only a little. In our experiment we tried a T Cell Activation model using a bispecific antibody blinatumomab (Blincyto) to bring together engineered Jurkat effector cells with Raji target cells that were tagged with the SmBiT and LgBiT on their extracellular surfaces. We did not have the BiTs fused to receptors. So far we have not gotten a reproducible increase in luminescence upon treatment with the bispecific antibody. However, we realized that we could be running into physical issues with getting the BiTs to interact because of the size of the antibody and the fact that the BiTs may not be extending very far out from the surface of the cell. We think that we may need put larger linkers on the extracellularly expressed BiT fusions to make sure that they can actually reach each other when the cells are brought together. In principle it does seem like this type of experiment should work, and perhaps fusing them to proteins that actually extend from the surface would be a better approach. However, I am not yet aware of any demonstrated success for this application. If anyone else has comments to share please let us know.
@Teresa, if you would like to be put in touch with the application scientist that performed the work described above please let me know. They may have some suggestions about important things to consider if you decide to give this a try.