GMP StemEdit OC-1 Protein

GMP Grade Open-Source Genome Editing for Clinical Application

StemEdit OC-1 Protein is a recombinant, AI-designed genome-editing nuclease developed as a next-generation alternative to conventional Cas nucleases. GMP StemEdit OC-1 Protein enables high editing efficiency with low off-target activity without a separate licensing fee. 

GMP StemEdit OC-1 Protein is designed to support clinical gene editing programs, including the development of gene-edited cell therapies.

Research-grade StemEdit OC-1 is also available, with the same sequence and purification method, and it is ideal for method development. 

Why Choose GMP StemEdit OC-1?

✔ Open-Source Technology
 Based on open-source OpenCRISPR-1™ (OC-1) technology, providing an alternative to conventional Cas nucleases. 

✔ High Editing Efficiency
Robust genome editing performance across a wide range of cell types.

✔ Low Off-Target Activity
Designed for precise and reliable genome modification.

✔ AI-Designed Technology
Engineered using advanced AI-guided protein design for next-generation genome editing.

✔ Full GMP support
Includes all documentation needed to support your GMP project (certificates, batch records, etc.).

How was StemEdit OC-1 Protein Created?

StemEdit OC-1 Protein was devised using large protein language models (LLMs) pre-trained on millions of naturally occurring CRISPR–Cas sequences to learn the underlying principles of functional genome editors. These models were then fine-tuned specifically on CRISPR–Cas data to guide generation toward proteins with the structural and functional characteristics of Cas9-like nucleases, creating novel gene editors far outside the range of sequences found in nature. OC-1 was identified from millions of sequences based on its strong editing activity, on-target efficiency comparable to traditional SpCas9, and reduced off-target effects in human cells, making it well-suited for genome engineering applications in stem cell and cell therapy research. 

Find out more about the science behind the OC-1 protein in our recent blog post.

Applications

• Knock-in of large gene fragments (e.g., reporters, regulatory elements)
• Knock-in of biallelic mutations for disease models or functional studies
• Knock-out of single or multiple genes

GMP StemEdit OC-1 Protein is intended for research and clinical-stage development projects involving gene editing.

For clinical therapeutic gene editing projects, please contact our (StemEdit) service team to learn more about our genome engineering services. 

See also:

• StemEdit Gene Edited iPSCs — Our hypoimmune iPSCs

• StemEdit Clinical Gene Editing Service — Our open-source editing services.

• Clinical Stem Cell Services — Clinical-grade iPSC solutions.

• StemRNA™ iPSCs — Research-grade iPSC collection.
  
  
  

Figure 1. GMP StemEdit OC-1 Protein was assayed for gene editing activity using a test guide RNA and a target cell, and the data were analyzed using the ICE App (https://ice.editco.bio/#/). This assay shows that this batch of OC-1 Protein achieved 90% indel formation, demonstrating robust gene editing activity.

Figure 2. Purity of GMP Stem Edit OC-1 Protein. OC-1 protein was analyzed by SDS-PAGE, and the purity was >90%.

Stemgent and the StemEdit brand name are trademarks of REPROCELL Inc., Japan. OpenCRISPR-1 is a trademark of Profluent Bio, Inc.

Product Specifications

Product Name

GMP StemEdit OC-1 Protein

Catalog Number

03-0020-GMP

Product Description

Purified recombinant OC-1 protein

Product Grade

GMP grade, suitable for clinical-stage development projects.
CoA, Batch Records, and QC Validation Records are available with purchase.

Size

130 µg (10 µL) 

Expression System

E. coli

Molecular Weight

164 kDa

Formulation

13 mg/mL in 20 mM Tris-HCl, 300 mM NaCl, 0.1 mM EDTA, 1 mM DTT, 50% glycerol, pH 7.4

This product is produced utilizing animal-origin-free, human-origin-free, and beta-lactam-free materials.

Storage

Store at 4°C if the entire vial will be used within 1-2 weeks. Store frozen at -20°C for longer periods of time. Avoid multiple freeze-thaw cycles.

Quality Control

• >90 % pure by SDS-PAGE
• Indel formation:  Pass

Sterility

Sterile

Notice To Purchaser

This product is suitable for therapeutic and diagnostic development and for research.  Commercial Use may require additional agreements. Please contact info-us@reprocell.com for more information.  

1. Ruffolo JA; Nayfach S; Gallagher J; Bhatnagar A; Beazer J: Hussain R; Russ J; Yip J; Hill E; Pacesa M; Meeske AJ; Cameron P; Madani A et al. Design of highly functional genome editors by modelling CRISPR–Cas sequences. Nature 645:518 (2025). DOI: 10.1038/s41586-025-09298-z