NEW YORK, NY — October 7, 2025 — Leads & Copy — Cellectis, a clinical-stage biotechnology company, will present findings on the potential of circular single-stranded DNA (CssDNA) for gene therapy and a study of TALE base editors (TALEB) off-targets at the European Society of Cell and Gene Therapy (ESGCT) annual congress in Sevilla, Spain, October 7-10, 2025.
Julien Valton, Ph.D., Vice President Gene Therapy at Cellectis, will present a poster on October 8, 2025, from 2:00 p.m. to 3:30 p.m. CET, highlighting CssDNA’s potential as a non-viral DNA template for long-term HSCs editing (Poster number: P0439).
The research indicates that the CssDNA editing process achieved high gene insertion frequency in viable hematopoietic stem and progenitor cells (HSPCs). CssDNA-edited HSPCs also demonstrated a higher propensity to engraft and maintain gene edits in a murine model compared to adeno-associated viruses (AAV)-edited HSPCs.
Additionally, Maria Feola, Ph.D., Senior Scientist, Team Leader Gene Editing at Cellectis, will present a poster on October 9, 2025, from 2:00 p.m. to 3:30 p.m. CET, regarding a comprehensive analysis of TALEB off-target editing (Poster number: P0506).
The study found no evidence of biases towards off-site C-to-T editing at sites flanked by CTCF binding sites, supporting the safe development of TALEB in therapeutic cell engineering.
The poster presentations are available on Cellectis’ website.
Pascalyne Wilson, Director, Communications, + 33 (0)7 76 99 14 33, media@cellectis.com
Patricia Sosa Navarro, Chief of Staff to the CEO, +33 (0)7 76 77 46 93
Arthur Stril, Chief Financial Officer & Chief Business Officer, investors@cellectis.com
Source: Cellectis
