Durham-based Stem Genomics joins Clean Cells to advance cell therapy quality testing

Clean Cells, a France-based provider of quality testing services for biopharmaceutical products, will acquire Stem Genomics, which provides next-generation quality controls for stem cell therapy. 

The acquisition, which includes Stem Genomics Inc., based in Durham, North Carolina, and Stem Genomics SAS in France, expands Clean Cells’ capabilities in quality testing for stem cell therapies.

“North Carolina has built what very few regions in the world can claim: an end-to-end life sciences ecosystem for cell and gene therapy, from academic research through clinical development to commercial manufacturing,” said Laurent Claisse, CEO of Clean Cells. “For a company like Clean Cells, whose clients are developers moving along that path, being implanted in that ecosystem was an important decision.”

From collaboration to integration

The acquisition of Stem Genomics builds on Clean Cells’ existing presence in the Research Triangle Park region, which began with its 2025 acquisition of KaryoLogic. KaryoLogic provides karyotyping and cytogenetics services to cell therapy developers and has been collaborating with Stem Genomics on stem cell testing for some time.

The two companies have shared buildings in Durham since their early stages, first in a smaller lab space, then moving together to the current location. 

“Stem Genomics and KaryoLogic were already operating as close partners, with complementary technologies, before either acquisition happened,” said Claisse. “When Clean Cells looked at Stem Genomics, we were formalizing something that the two teams had already proven to be working.”

The strength of those existing partnerships reflects the broader ecosystem that has developed in N.C. Claisse adds that the research institutions, large network of contract research organizations, and steady flow of new cell and gene therapy programs have made N.C. a natural fit for companies providing specialized quality testing.

Reliable partners for quality control 

The acquisition comes as regulators in the US, Europe, and Japan are raising the bar on what developers need to demonstrate before moving into clinical trials. As more complex induced pluripotent stem cell (iPSC)-derived and chimeric antigen receptor T-cell (CAR-T) therapies enter development, the need for quality control in cell therapy continues to expand.

“With this deal, we are expanding our ability to support research teams from their early genomic stability testing through to cell banking and viral safety testing to GMP lot release,” said Claisse.  “Stem Genomics brings its innovative proprietary technology, a strong US footprint and an expert team that understands stem cell biology at a level that takes years to build. This is the missing piece that completes our cell therapy quality control platform.”

The acquisition includes Stem Genomics’ core asset, the iCS-digital PSC assay. This proprietary digital PCR-based test is used for genomic stability testing of human Pluripotent Stem Cells (hPSCs). It detects more than 93% of recurrent chromosomal abnormalities in stem cell cultures, with results available in just a few days. It is available as a Contract Research Organization (CRO) service and as a kit. 

Other assets include the Stem-Seqrange, the next-generation sequencing solutions for comprehensive detection of genomic abnormalities, the Pluri-digital assay for pluripotency and differentiation monitoring, and other assays for routing testing such as cell line authentication and mycoplasma detection.

“We built this company to help researchers trust their cell lines and with Clean Cells we can now follow those same clients all the way into the clinic,” said Nicolas Chapal, CEO of Stem Genomics, the company he co-founded with Pr. John De Vos and Dr. Saïd Assou, researchers at the University of Montpellier, France. “This is a critical next step for us.” 

Chapal will serve as managing director of the new Stem Cell Business Unit, leading both Stem Genomics and the previously acquired KaryoLogic. All 17 employees from Stem Genomics are retained across both the French and US entities, and the two sites will continue operating without interruption.

Looking ahead

With the acquisition, Clean Cells plans to continue to develop a single site in Durham where clients can access genomic stability testing through Stem Genomics and karyotyping services through KaryoLogic, under one roof, from one team. 

Stem Genomics will support developers at the research stage, where speed, flexibility and scientific depth matter most. Then, when those programs advance and require Good Manufacturing Practice (GMP)-grade biosafety testing, viral safety, or lot release support, Clean Cells can handle that transition from the French headquarters. 

“The two layers are designed to work together,” said Claisse. “For an N.C.-based biotech moving from research into the clinic, that means continuity of a partner across the full quality control journey, without switching providers at the most critical stage.”  

Read more: 
Durham’s KaryoLogic Partners with French Firm for Stem Cell Testing