The Therapeutic Effect of Pamidronate on Lethal Avian Influenza A H7N9 Virus Infected Humanized Mice

PLoS One. 2015 Aug 18;10(8):e0135999. doi: 10.1371/journal.pone.0135999. eCollection 2015.

Abstract

A novel avian influenza virus H7N9 infection occurred among human populations since 2013. Although the lack of sustained human-to-human transmission limited the epidemics caused by H7N9, the late presentation of most patients and the emergence of neuraminidase-resistant strains made the development of novel antiviral strategy against H7N9 in urgent demands. In this study, we evaluated the potential of pamidronate, a pharmacological phosphoantigen that can specifically boost human Vδ2-T-cell, on treating H7N9 virus-infected humanized mice. Our results showed that intraperitoneal injection of pamidronate could potently decrease the morbidity and mortality of H7N9-infected mice through controlling both viral replication and inflammation in affected lungs. More importantly, pamidronate treatment starting from 3 days after infection could still significantly ameliorate the severity of diseases in infected mice and improve their survival chance, whereas orally oseltamivir treatment starting at the same time showed no therapeutic effects. As for the mechanisms underlying pamidronate-based therapy, our in vitro data demonstrated that its antiviral effects were partly mediated by IFN-γ secreted from human Vδ2-T cells. Meanwhile, human Vδ2-T cells could directly kill virus-infected host cells in a perforin-, granzyme B- and CD137-dependent manner. As pamidronate has been used for osteoporosis treatment for more than 20 years, pamidronate-based therapy represents for a safe and readily available option for clinical trials to treat H7N9 infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Blotting, Western
  • Bone Density Conservation Agents / pharmacology
  • Cells, Cultured
  • DNA-Binding Proteins / physiology
  • Diphosphonates / pharmacology*
  • Humans
  • Immunoenzyme Techniques
  • Influenza A Virus, H7N9 Subtype / pathogenicity*
  • Influenza, Human / drug therapy*
  • Influenza, Human / immunology
  • Influenza, Human / virology
  • Lung / drug effects*
  • Lung / virology
  • Mice
  • Mice, Knockout
  • Orthomyxoviridae Infections / drug therapy*
  • Orthomyxoviridae Infections / immunology
  • Orthomyxoviridae Infections / virology
  • Pamidronate
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • T-Lymphocyte Subsets
  • Virus Replication / drug effects*

Substances

  • Bone Density Conservation Agents
  • DNA-Binding Proteins
  • Diphosphonates
  • RNA, Messenger
  • Rag2 protein, mouse
  • Pamidronate

Grants and funding

This work was supported in part by General Research Fund, Research Grants Council of Hong Kong (HKU 780113M), Area of Excellence program on Influenza (AoE/M-12/06) of Hong Kong SAR, China, and Dr. Richard YH Yu. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.