Regocel™ Supplement for Hybridoma Cells (RSDoma™) 5000X CONCENTRATE RSDoma™ is intended for use with hybridoma cells growing in small, midsize or largescale cultures grown under agitated or nonagitated conditions. Here we provide the protocol for 125 ml shake flasks which can represent midlarge scale cultures. Adapt as necessary for static culture in Tflasks or culture plates/dishes. A variety of media (defined, animalfree, and serumfree) can be used with RSDoma™. Use your preferred commercial or inhouse hybridoma medium. Hybridoma cells to be seeded should be healthy and in log phase growth. Hybridoma cells express and secrete immunoglobulin (Ig) into the medium. Methods to quantify Ig such as ELISA should be established inhouse. In many cases, commercial ELISA kits are available to measure protein.