Methods of CD34+ cell separation: comparative analysis.

During the last decade, several technologies based on the recognition of CD34 antigen have been proposed to purify hematopoietic cells for clinical use. The following review describes the different approaches, including panning, high-speed activated cell sorting, immunomagnetic selection and immunoadsorption column separation. Positive selection of hematopoietic stem cells is now an essential step in cellular therapy. Quantitative and qualitative aspects of each system will be discussed as well as technical progress in the clinical setting.