Effect of endotoxin on cells and on their response to infection by polioviruses

Optimizing interleukin-6 and 8 expression, clarification and purification in plant cell packs and plants for application in advanced therapy medicinal products and cellular agriculture

Healthcare and nutrition are facing a paradigm shift in light of advanced therapy medicinal products (ATMPs) and cellular agriculture options respectively. Both options heavily rely on some sort of animal cell culture, e.g. autologous stem cells. These cultures require various growth factors, such as interleukin-6 and 8 (IL-6/8), in a pure, safe and sustainable form that can be provided in a scalable manner. Plants seem well suited for this task because purification of small proteins can be readily achieved by membrane separation, human/animal pathogens do not replicate in plants and production can be scaled up using in-door farming or agricultural practices. Here, we illustrate this capacity by first optimizing the codon usage of IL-6/8 for translation in Nicotiana spp., as well as testing the effect of untranslated regions and product targeting to different sub-cellular compartments on expression in a high-throughput plant cell pack (PCP) assay. In the chloroplast, IL-6 accumulated up to 6.9±3.8 (SD, n=2) and 14.4±7.4 mg kg-1 (SD, n=5) were observed in case of IL-8. When transferring IL-8 expression into whole plants, accumulation was 12.3±1.5 mg kg-1 (SD, n=3). After extraction and clarification, IL-8 was purified using a two-stage process consisting of an ultrafiltration/diafiltration step with 100 kDa and 10 kDa cut off membranes followed by an IMAC polishing step. The purity, yield and recovery were 97.8%, 6.6 mg kg-1 and 38%, respectively. We evaluated the ability of the proposed purification process to remove endotoxins to ensure the compatibility of plant-made growth factors with cell culture.

THE EFFECT OF ENDOTOXIN ON THE THYMUS OF YOUNG MICE

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Effect of triiodothyronine on cells and on their response to infection by polioviruses

Murphy, W. H. (The University of Michigan, Ann Arbor) and Cora Bullis. Effect of triiodothyronine on cells and on their response to infection by polioviruses. J. Bacteriol. 83:641-648. 1962.-An analysis was made of the effect of triiodothyronine (T3) at physiological (1 mug/ml) and maximal subliminal toxic levels (35 mug/ml) on HeLa-S3, HeLa-Gey, Chang-liver, and Maben cells, and on their response to infection by cytopathic and submoderate (noncytopathic) mutants of type 2 poliovirus. Assays of cell response to T3 alone, or in combination with the mutants of poliovirus, were made by conventional monolayer cell culture techniques, by study of the effect of T3 on plating efficiency of cells, and by study of its influence on colonies of cell variants. Cellular response to liminal doses of T3 was characterized by agglutination of cells and thickening of the cell membrane. Compact colonies of Chang-liver and Maben cells were the most sensitive to maximal subliminal amounts of T3. T3 in combination with cytopathic or submoderate (noncytopathic) mutants of poliovirus slightly increased the rate of destruction of cells susceptible to virus, but did not influence yield of virus from cell cultures. T3 at physiological or subliminal concentrations did not induce cytopathic response of cell cultures latently infected by submoderate poliovirus.