Cytokines and growth factors are made in biological systems and can be susceptible to variability. They should only be released to market after successful manufacturing of many consecutive batches that have passed stringent specifications. This builds a solid foundation for future manufacturing consistency and reliability.
Manufacturing processes must be controlled with rigorously documented SOPs and highly trained staff. This information should be made available during audit. It is fair to request data from several lots in order to assess a vendorís ability to make proteins reproducibly. Ideally, materials from multiple lots should be obtained so they can be tested for consistency in your system. At Bio-Techne, we maintain master control lots. Each new bulk lot is compared against the master lot prior to release to market. This reduces variability and ensures consistent product performance.