We're thrilled to expand our PluriBank™ RUO portfolio with new, low-passage PluriBank™ RUO FailSafe^® lines that features enhanced immune evasion through reduced T cell recognition and a selective ablation mechanism to remove dividing cells while preserving post-mitotic cells. This innovative line integrates mRNA-reprogrammed iPSCs with CRISPR-based knockouts of B2M and CIITA genes, plus the FailSafe safety switch. For flexibility, we also offer a sister line with only the FailSafe knock-in.

For consistent and reproducible culture of PluriBank™ RUO FailSafe® lines, Pluristyx recommends PluriKit™, a set of reagents tests and selected for their ability to maintain cell viability, pluripotency, and genomic integrity throughout culture and cryopreservation.

Comprehensive usage instructions are available in our Instructions for Use.

FailSafe

HSV-TK is a viral enzyme that processes the non-toxic ganciclovir pro-drug into a cytotoxic product. FailSafe cells have HSV-TK gene inserted into an essential cell division locus¹. This provides researchers with a potent tool for time and dose-dependent ablation of dividing cells in culture while leaving post-mitotic cells intact. For cell therapy, the FailSafe cell system can be used as a safety switch that selectively eliminates dangerous proliferating cells while allowing post-mitotic therapeutic cells to remain and continue benefiting the patient.

B2M CIITA Knock out

The B2M gene is critical for MHC class I molecule expression, while CIITA is necessary for MHC class II expression. Removing B2M disrupts the presentation of antigens on MHC class I molecules, helping the transplanted cells evade detection by the recipient’s cytotoxic T cells. Similarly, knocking out CIITA prevents the expression of MHC class II molecules, which reduces the likelihood of recognition by helper T cells. Together, these knockouts minimize immune activation against transplanted cells, increasing their survival and functionality in the recipient. Knocking out B2M and CIITA, in conjunction with knocking in a gene to help cells evade innate immunity is used as the basis for several hypo-immune platforms ^2,3.

Cell line

These edits are made available on the Pluristyx PSXi013 line: a male Caucasian fibroblast reprogrammed line using mRNA technology. PSXi013-A iPSCs have shown promising differentiation potential in the hands of partners and collaborators into islet cells, hepatocytes, CD34+ progenitors, NK cells, neurons, and cardiomyocytes.