Pixelgen Raises $15,5 Million to Commercialize Single-Cell Measurement of Protein Proximity

Pixelgen Raises $15,5 Million to Commercialize Single-Cell Measurement of Protein Proximity

On August 20, Pixelgen announced a $15,5 million Series B round. Flat Capital led the round, while existing investors Industrifonden and Navigare Ventures continued their participation. The company will use the funding to commercialize the Proxiome Kit globally, expand its team, and broaden its product portfolio.

Proteins on the cell surface allow the cell to receive and respond to external signals. Conventional single-cell analysis identifies which of these proteins are present and measures their abundance. The Proxiome Kit adds spatial information by showing which proteins form clusters and which proteins are close to one another on the cell membrane.

The kit is based on the Proximity Network Assay. The cells are fixed, after which antibodies carrying DNA barcodes bind to selected surface proteins. The barcodes are copied repeatedly near each binding site. Adjacent copies are then joined and read by sequencing, a method for determining DNA sequences. An algorithm uses these connections to construct a map showing protein abundance, protein clusters, and the proximity of different proteins to one another.

In a preprint, the authors described a panel of 155 plasma membrane proteins and applied the method to blood cells, blood cancer cell lines, CAR-T models, and samples from autoimmune diseases. They obtained tens of thousands of spatial nodes and about 12 thousand pairwise protein relationships from a single cell. Each sample provides both the usual list of protein markers and a map of their spatial relationships on the cell surface.

Pixelgen is turning this measurement method into a commercial kit. Laboratories will be able to compare cells not only by which proteins they contain, but also by how those proteins are positioned relative to one another.