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In the pharmaceutical industry, the need for high levels of protein expression in mammalian cells has prompted the search for new strategies, including technologies to obtain cells with improved mechanisms that enhance its transcriptional activity, folding, or protein secretion. Chinese Hamster Ovary (CHO) cells are by far the most used host cell for therapeutic protein expression. However, these cells produce specific glycans that are not present in human cells and therefore potentially immunogenic. As a result, there is an increased interest in the use of human-derived cells for therapeutic protein production. For many decades, human embryonic kidney (HEK) cells were exclusively used for research. However, two products for therapeutic indication were recently approved in the United States. It was previously shown that tethered Magoh, an Exon-junction complex core component, to specific mRNA sequences, have had significant positive effects on mRNA translational efficiency. In this study, a HEK Magoh-overexpressing cell line and clones, designated here as HEK-MAGO, were developed for the first time. These cells exhibited improved characteristics in protein expression, reaching --two- to threefold increases in rhEPO protein production in comparison with the wild-type cells. Moreover, this effect was promoter independent highlighting the versatility of this expression platform. [ABSTRACT FROM AUTHOR]

Current Food and Drug Administration (FDA)-approved CD19-specific chimeric antigen receptor (CAR) T-cell therapies for B-cell malignancies are constitutively active and while efficacious, can cause morbidity and mortality. Their toxicities might be reduced if CAR T-cell activity was regulatable rather than constitutive. To test this, we compared the efficacies and morbidities of constitutively active (conventional) and regulatable (switchable) CAR (sCAR) T-cells specific for human CD19 (huCD19) in an immune-competent huCD19 + transgenic mouse model.Conventional CAR (CAR19) and sCAR T-cells were generated by retrovirally transducing C57BL/6 (B6) congenic T-cells with constructs encoding antibody-derived single chain Fv (sFv) fragments specific for huCD19 or a peptide neoepitope (PNE), respectively. Transduced T-cells were adoptively transferred into huCD19 transgenic hemizygous ( huCD19 Tg/0 ) B6 mice; healthy B-cells in these mice expressed huCD19 Tg Prior to transfer, recipients were treated with a lymphodepleting dose of cyclophosphamide to enhance T-cell engraftment. In tumor therapy experiments, CAR19 or sCAR T-cells were adoptively transferred into huCD19 Tg/0 mice bearing a syngeneic B-cell lymphoma engineered to express huCD19. To regulate sCAR T cell function, a switch protein was generated that contained the sCAR-specific PNE genetically fused to an anti-huCD19 Fab fragment. Recipients of sCAR T-cells were injected with the switch to link sCAR effector with huCD19 + target cells. Mice were monitored for survival, tumor burden (where appropriate), morbidity (as measured by weight loss and clinical scores), and peripheral blood lymphocyte frequency.CAR19 and sCAR T-cells functioned comparably regarding in vivo expansion and B-cell depletion. However, sCAR T-cells were better tolerated as evidenced by the recipients' enhanced survival, reduced weight loss, and improved clinical scores. Discontinuing switch administration allowed healthy B-cell frequencies to return to pretreatment levels.In our mouse model, sCAR T-cells killed huCD19 + healthy and malignant B-cells and were better tolerated than CAR19 cells. Our data suggest sCAR might be clinically superior to the current FDA-approved therapies for B-cell lymphomas due to the reduced acute and chronic morbidities and mortality, lower incidence and severity of side effects, and B-cell reconstitution on cessation of switch administration., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Compliance with Food and Drug Administration regulations relating to initiating early phase clinical trials of new cellular therapy products often presents a hurdle to new investigators. One of the biggest obstacles is the requirement to manufacture the therapeutic products under current Good Manufacturing Practices-a system that is usually poorly understood by both basic researchers and clinicians. This article reviews the major points that must be addressed when manufacturing genetically modified T cells for therapeutic use.

Biomedical advances in vision research have been greatly facilitated by the clinical accessibility of the visual system, its ease of experimental manipulation, and its ability to be functionally monitored in real time with noninvasive imaging techniques at the level of single cells and with quantitative end-point measures. A recent example is the development of stem cell-based therapies for degenerative eye diseases including AMD. Two phase I clinical trials using embryonic stem cell-derived RPE are already underway and several others using both pluripotent and multipotent adult stem cells are in earlier stages of development. These clinical trials will use a variety of cell types, including embryonic or induced pluripotent stem cell-derived RPE, bone marrow- or umbilical cord-derived mesenchymal stem cells, fetal neural or retinal progenitor cells, and adult RPE stem cells-derived RPE. Although quite distinct, these approaches, share common principles, concerns and issues across the clinical development pipeline. These considerations were a central part of the discussions at a recent National Eye Institute meeting on the development of cellular therapies for retinal degenerative disease. At this meeting, emphasis was placed on the general value of identifying and sharing information in the so-called "precompetitive space." The utility of this behavior was described in terms of how it could allow us to remove road blocks in the clinical development pipeline, and more efficiently and economically move stem cell-based therapies for retinal degenerative diseases toward the clinic. Many of the ocular stem cell approaches we discuss are also being used more broadly, for nonocular conditions and therefore the model we develop here, using the precompetitive space, should benefit the entire scientific community.