The ethical issues surrounding human immunization hamper the production of human monoclonal antibody through scarcity of immunized B cells in peripheral blood. This defect can be compensated in part by improvement of hybridoma production techniques. We have developed a new strategy to bypass the toxic effects of polyethylene glycol (PEG) as fusogenic reagent and hypoxanthine aminoptrin thymidine (HAT) as selective medium on newly fused cells. The Epstein-Barr virus (EBV) transformed peripheral blood mononuclear cells (PBMC) of accidentally Rh antigen sensitized persons were fused using cephalin as fugenic reagent, with emetine and actinomycin D pretreated heteromyeloma cells. Our results showed that 19–34% of EBV-transformed B cells were grown as hybridoma clones following selection. This extreme improvement in hybridoma production rate may end the fusion efficiency problem and make hybridoma production a plug-and-play technology.