Abstract: Influenza virus affects the respiratory tract in humans causing a range of distinct manifestations including fever, nasal
secretions, cough, headaches, muscle pain and pneumonia, which could become violent and severe. It was found that influenza A
viruses remain resistant to amantadine and rimantadin with high level of oseltamvir resistance. Therefore, there is a need for constant
improvement of drugs active against resistant influenza viruses. Propolis has anti-influenza activity both in vitro and in vivo. Human
leukocyte interferon (HuIFN-αN3) is a multi-subtype protein that displays an antiviral activity against influenza virus. In this study
we elucidated the anti-influenza activity of the mixes of water-soluble propolis (WSP) (Greit 120) and HuIFN-αN3 at different ratios.
Greit 120 polyphenols, total phenol acids and bioflavonoid were characterized by HPLC-UV-ESI-MS504971 and HuIFN-αN3 by
reverse-phase high-performance liquid chromatography (RP-HPLC). Influenza A and B viruses were separately added to the
LLC-MK2 cells treated with WSP (Greit 120) and HuIFN-αN3 alone or in proportions 1:1, 1:2 and 2:1. Plates were incubated and
cytopathic effect was determined. The best results (ID50) were obtained with the mix of 10% WSP and HuIFN-αN3 in proportion 1:2,
showing ID50 at 12 ± 0.2 μg/mL and 19 ± 0.6 μg/mL for influenza A and B viruses, respectively. When comparing anti-influenza
activity of WSP (Greit 120)/HuIFN-αN3 with that of ribavirin, it was found that 1:2 was the optimal ratio for WSP (Greit
120)/HuIFN-αN3 (0.5 and 0.6 for influenza A and B, respectively). This new formulation of WSP (Greit 120) and HuIFN-αN3,
showing better anti-Influenza activity, will definitely improve its application in flu infections
