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Minicircle DNA vectors are superior to plasmids for long-term transgene expression but are not in widespread use because of a laborious production process. Kay et al. present an improved protocol for generating minicircles that makes them a viable alternative to plasmids for gene transfer studies.
The development of fully defined culture conditions for human embryonic stem cells (hESCs) should enhance experimental reproducibility, reduce unwanted contaminants and facilitate scale-up production. Villa-Diaz et al. show that a substrate made of the synthetic polymer PMEDSAH supports long-term culture of hESCs.
A correlation between drug exposure and efficacy has never been demonstrated for therapeutic antibodies. Zalevsky et al. use a humanized mouse model to show that a reduction in antibody clearance engineered through increased antibody affinity for the neonatal Fc receptor enhances antitumor activity.