Multus Proliferum® B

Proliferum B is a panel of animal component-free serum replacements developed to replace foetal bovine serum in bovine and murine cell culture systems. It provides a defined alternative that supports consistent, scalable media development for cultivated meat research. The product consists of four distinct formulations designed for comparative optimisation, enabling researchers to determine the most suitable variant for their specific cell types and process conditions.

Each formulation has been evaluated across several bovine and murine models, including primary fibroblasts, immortalised fibroblasts, and satellite cells. Growth studies demonstrated doubling times and morphology comparable to 10 per cent FBS, with formulation-specific preferences observed across cell types. PB01 supported strong proliferation in EBTr, BDF, and iBSC lines, PB02 performed best with primary bovine muscle fibroblasts, and PB03 showed optimal compatibility with murine 3T3-L1 cells. PB04 is included to broaden testing coverage across additional fibroblast-like lines. These results indicate that all four formulations provide viable alternatives to serum across early-stage and scale-up workflows.

The product is supplied as a sterile frozen liquid and should be stored at −20 °C until use. Thawing at room temperature in the dark is recommended. Once thawed, Proliferum B is diluted into basal media such as DMEM/F12 at 1–2× strength, with titration recommended to establish cell-specific requirements. Prepared medium should be used within one to two weeks and refreshed every forty-eight hours. The formulations support both direct transition from FBS and a staged adaptation process where needed.

Multus recommends evaluating all four variants during initial optimisation to identify the formulation that delivers the best growth characteristics for each cell model.