Targeting dsRNA-specific single-chain Fv antibody fragments to different cellular locations in Nicotiana tabacum L.

Expression of antibodies or antibody fragments in plants is a useful tool for producing active antibody derivatives for diagnostic or pharmaceutical purposes as well as for immunomodulation. We investigated the effect of cellular expression site on the stability and yield of double-stranded RNA (dsRNA)-specific single-chain Fv-fragments (scFv) in transgenic tobacco. Two antibodies (J2 and P6) belonging to the V23(J558) heavy chain variable gene family but differing in the light chain variable domain were used. scFvs were targeted to the cytoplasm – with or without anchoring them in the plasma membrane –, into the endoplasmic reticulum (ER) and to the apoplast. Although high mRNA concentrations were detected in all cases, scFv proteins accumulated only when scFvs were made ER-resident by appropriate signal sequences. When the ER retention signal was removed to allow scFv-secretion to the apoplast, no scFv-proteins were detected. Despite the strong homology of the VH-sequences of J2 and P6 antibodies, only P6 provided a stable scFv scaffold for intracytoplasmic expression. J2-scFv could not be stabilised neither by adding a C-terminal stabilisation signal nor by anchoring the protein at the cytoplasmic side of the plasma membrane (PM). It was found that dsRNA-specific J2-scFvs are active in vivo and enhance Potato Virus Y induced symptoms in infected tobacco. This is the first report describing the expression and biological effect of RNA-specific antibodies in plants.

Value creation and appropriation through the Hungarian SME’s food chain

Value creation is the result of the continuous innovation activity of the entrepreneur, which is carried out mainly in form of open innovation among the agri-food SMEs. However value creation is not the ultimate goal of the enterprises. They are more interested in increased appropriation of the created value. Although the value creation (innovation) is very well explored and cultivated area of research, there are some voids in the field of agriculture and food industry: the behavioural aspect of open innovation is very rare. The value capturing is even much less studied, therefor our research approach is largely explorative one. Data are drawn from a survey carried out in Hungary among the agri-food SMEs in 2014. We use Structural Equation Modelling as well as ordered probit and semi-non parametric ordered probit models for analysing the data. Our results show that there is positive relationship between the knowledge sharing with chain partners and the innovativeness. We could explore that size of the firm, absorptive capacity and openness to foreign trade ambiguously affects value capturing. However trust in chain partners, reciprocity in knowledge sharing with chain partners and willingness to cooperate with buyers positively influence the appropriation of the created value.