Stability liabilities of biotherapeutic proteins: Early assessment as mitigation strategy.

Identification of molecular liabilities and implementation of mitigation strategies are key aspects that need to be considered by pharmaceutical companies developing therapeutic proteins. In the field of monoclonal antibodies, an efficient and streamlined process known as developability assessment is used for the selection of the "fittest" candidate. Other protein modalities, have in most cases only a limited number of possible candidates, requiring a paradigm change to a concept of candidate enabling. The assessment of liabilities at early project phases with the possibility to re-engineer candidates becomes essential for the success of these projects. Each protein possesses a unique stability profile resulting from the interplay of conformational, colloidal, chemical and physical stability attributes. All of these attributes strongly depend on external factors. Conformational and colloidal stability profiles of three non-immunoglobulin domain based proteins, namely Carbonic anhydrase, Ovalbumin and Thyroglobulin, and of two monoclonal antibodies were assessed in dependence of solution pH, ionic strength and varying buffering agents. The impact of screened external factors on proteins' stability attributes varied significantly, indicating presence of molecule specific liabilities. Screening of such a broad space of conditions at early project phases is only feasible using low-material consuming, high-throughput analytical methods as exemplified in this study.

Rapid phenotyping of the tomato fruit model, Micro-Tom, with a portable VIS-NIR spectrometer.

Tomato (Solanum lycopersicum) quality traits such as juice soluble solid content (Brix), juice pH, color parameters (Hue and Chroma), firmness and water content, are critical factors for fruit quality assessment. The need for screening very large numbers of fruit has led to the development of a high-throughput method using visible-near infrared (VIS-NIR) spectrometry. We are reporting here a set of results obtained with a portable spectrometer using the 350-2500 nm range, showing good prediction of the quality traits cited above, over a wide range of developmental stages from immature green to ripe tomato fruit, cv. Micro-Tom. This is a rather good set of quality traits compared to previous publications predicting tomato quality with VIS-NIR spectrometry, and the prediction is robust, as it was obtained by grouping sets of different operators. This would be a useful tool to phenotype hundreds of Micro-Tom per day, making it possible to follow the dynamics of the described parameters on growing fruits. Thus the method can be used to study the biochemistry and physiology of fruit development in planta.