It is OK to use research use only (RUO) reagents, even as a primary source when GMP for manufacturing isn’t available. If this is the case, you should still be asking the same questions of the supplier that you would if they were manufacturing using GMP for Cell Therapy. You still have the same concerns about lot-to-lot consistency, scalability, and supply chain. At minimum, a vendor should have an ISO 9001:2008/2015-certified quality management system. This means the supplier has been independently audited, and should have a document and record management system that includes manufacturing records, a supplier qualification monitoring program, and more. R&D Systems’ RUO reagents are manufactured under this system. Also, early communication with regulatory authorities can also ensure there are no issues using the reagent. Lastly, a supplier with the capability can initiate a custom project to supply your reagent under GMP for manufacturing guidelines.