Production of Human Monoclonal Antibodies to Hepatitis C Virus and Their Characterization

Human monoclonal antibodies (hMAb) provide novel ways to probe the B-cell repertoire in health and disease. However, the development of hMAb technology has met with several difficulties owing to the instability of the cell lines, the low level of specific antibody secretion, and the poor cloning efficiency, particularly when using lymphoblastoid cells (1 ,2 ). In order to overcome these problems, some investigators have fused human B lymphocytes with human/mouse myeloma heterohybrids. However, in such systems, human chromosomes are unstable and may occasionally be deleted. Despite the potential emergence of technical pitfalls, B-cell immortalization with EBV has been extensively used for hMAb production, because of its simplicity and because EBV can bind to and penetrate in virtually all B lymphocytes, theoretically allowing the exploration of the whole B-cell repertoire. The most recent protocols have made use of techniques aimed at expanding the population of antigen-specific B-cell precursors and improving the capacity of B-cells to grow at low density. These methods will be discussed below.