Increase Expression of HBsAg in Transgenic Potato Plants and Challenges of Vaccine Production in Transgenic Plants

The hepatitis B virus is a dangerous infectious agent, with an estimated 300 million carriers worldwide. Therefore, developing effective vaccine production methods is essential. One such method involves the use of transgenic plants. Several factors influence foreign gene expression in transgenic plants, including the type of genes, their chromosomal location, and the promoter used. Based on these factors, various expression cassettes can be designed for transgenic plants.In this study, we designed an expression cassette for transgenic potato plants. Promoters play a crucial role, as some are tissue-specific while others are inducible. Additionally, certain elements can enhance or silence gene expression in transgenic plants. Enhancer sequences derived from plant viruses are also utilized. To increase the expression level of HBsAg in transgenic potato plants, the tobacco etch virus (TEV) 5 untranslated region and the Patatin promoter were employed. The results demonstrated that in the highest-producing transgenic plant, the expression level of HBsAg increased threefold when both patatin and TEV were used together, compared to plants containing only the patatin promoter without TEV. Furthermore, a comparison with pCaMV combined with TEV revealed that the use of patatin and TEV resulted in a 4-5 times higher expression level.