In this video, we demonstrate the technique to measure transcellular interactions between synaptic cell adhesion molecules through the HEK cell aggregation assay. In this assay, an equal number of HEK cells expressing a desired presynaptic cell adhesion molecule and a fluorescent protein are mixed with HEK cells expressing a post-synaptic cell adhesion molecule and another fluorescent protein. The interaction between the cell adhesion molecules forces the cells to aggregate, which can be measured by fluorescence microscopy.
Protocol
1. Cell culture and transfection Make HEK cell media with DMEM, 1x (Dulbecco's Modification of Eagle's Medium) supplemented with 4.5 g/L glucose, L-glutamine & sodium pyruvate, and 10% FBS. Sterile filter. Predetermine suitable ligands and receptors for aggregation assay. NOTE: Neurexin3α SS4+/- and one of its known ligands, LRRTM2, were used in this study. Ligands and receptors of interest were expressed from cDNAs in pcDNA3.1. A Gibson assembly was used to …
Disclosures
The authors have nothing to disclose.
Materials
5 mL disposable microtubes with snap caps
VWR
89000-028
Incubation of mixed population of HEK cells
1000 mL Rapid—Flow Filter Unit, 0.2 um aPES membrane