Stability of Biologically Active Human Interferon α-2b in Transgenic "Long-Shelf Life" Tomatoes and Their Progeny

Human interferon α-2b (HuIFNα-2b) is a cytokine with antiviral and antiproliferative activities and is widely used as a therapeutic protein. Here, we investigated the production of biologically active HuIFNα-2b in transgenic tomato plants. Long-shelf-life Solanum lycopersicum L. cv. 'Shedevr 1' plants were transformed via an Agrobacterium-mediated protocol using the binary vector pCB124 carrying nptII and HuIFNα-2b genes. PCR and RT-PCR analyses confirmed transgenes presence and expression in regenerated kanamycin-resistant plants. Antiviral activity was evaluated in vitro by the inhibition of vesicular stomatitis virus replication in MA-104 epithelial cells. Interferon activity reached 14.90 × 10³ IU g^-1 FW in fresh fruit pulp and 854.00 × 10³ IU g^-1 FW in leaves. Importantly, transgenic fruits retained substantial activity (2.42 × 10³-6.72 × 10³ IU g^-1 FW) after three months of storage, with detectable activity (0.36 × 10³ IU g^-1 FW) remaining after five months. Transgene inheritance and interferon activity were confirmed in the T₁ and T₂ generations. These results demonstrate the potential of long-shelf-life transgenic tomatoes as a platform for the production and extended storage of biologically active recombinant proteins, potentially reducing dependence on costly purification and cold storage procedures.