Monoclonal antibodies for use in research are commonly developed in media supplemented with foetal bovine serum. Drug Discovery and Clinical Diagnostic arenas have differing requirements and techniques have been developed to enable cells to be adapted to protein-free environments. This has often resulted in the requirement for the development of new monoclonal antibodies suitable for serum-free conditions or the adaptation of existing hybridomas to serum-free environments. APS has developed a custom service providing cell line adaptation and, if required, scale up using protein free media ensuring product purity and consistency. Our cell culture team has considerable experience working with an extensive cross section of hybridomas and other mammalian lines, ranging from poorly secreting recalcitrant lines produced in academic labs through to high performance lines producing antibodies for pre-clinical studies.