Expression of Biologically Active Human Tumor Necrosis Factor- α in Transgenic Potato Plant

Abstract

We report the successful insertion of the cDNA of human tumor necrosis factor-α (HuTNF-α) into the genome of potato plant species, Solanum tuberosum, using Agrobacterium tumefacience-mediated transformation. HuTNF-α is a known and essential cytokine mediating host defense against tumors and infectious diseases and an immunomodulating agent. To enhance the accumulation of foreign gene product expression in plant cells, the molecular design of the constructed HuTNF-α is presented. Transcription and translation of TNF-α in transformants were confirmed by Northern blot, RT-PCR, ELISA, and Western blot, respectively. Expression of the bioactive HuTNF-α in plant cells was confirmed by way of the cytotoxic effect of the extract obtained from the transformants against murine L929 cells. We think that the expression level of HuTNF-α (15 μg/g potato plant tissue) obtained in the present study may be sufficient to induce responses/effects similar to those generated by TNF-α in human milk administered orally. We believe that the TNF-α expressed in edible potato plants has tremendous potential for clinical use in the areas of medicine and veterinary science. Its usefulness and applicability, therefore, need to be fully explored.