Nanotech vaccine sheds light in fight against lethal virus

Taipei, May 14 (CNA) A research team comprising scientists from Taiwan and the United States may have found an effective vaccine for the Middle East respiratory syndrome coronavirus (MERS-CoV), a highly lethal emerging disease with a mortality rate of over 34 percent.

Scientists at the University of Texas Medical Branch (UTMB), National Taiwan University (NTU) and Academia Sinica have developed a novel nanoparticle vaccine that mimics the morphology of MERS-CoV and has been found to protect against the infectious pathogen, Academia Sinica told the press in Taipei Tuesday.

Using nanotechnology, the team created capsid-like polymeric nanoshells before coating them with a protein corona to mimic coronavirus. It then loaded these nanoparticles with a potent immunologic stimulant to make the vaccine, according to the top academic research institution in Taiwan.

"In a mouse model, the vaccine stimulated a high and durable level of anti-MERS-CoV antibodies that can neutralize MERS-CoV antigens," Academia Sinica said in a statement.

"In addition, the vaccine also triggered an elevated level of antigen-specific T cells, which is critical for MERS-CoV protection," the statement said.

The inventor of the capsid-like polymeric nanoshell, Academia Sinica assistant research fellow Hu Che-ming (胡哲銘) explained that the vaccine functions to trick the body into believing it is being attacked, thus simulating the body's immune reactions in advance so that it can defend itself when the real virus attacks.

In short, "the vaccine mimics the characteristics of the virus," Hu said.

Unlike live attenuated virus vaccines, the nanoparticle vaccine has greater safety and is comprised entirely of biocompatible materials, Academia Sinica said.

In a study with live MERS-CoV challenge, mice vaccinated with the nanoparticle vaccine showed 100 percent survival, whereas all the non-vaccinated mice succumbed to the lethal challenge, the institution said.

"The nanoparticle vaccine has proven to be safe and effective against a lethal challenge of MERS-CoV in a transgenic mouse model," it said in the statement.

The international team aims to assess the nanoparticle vaccine in non-human primates before moving to clinical testing, it added.

Since the first identified case of MERS in 2012 in Saudi Arabia, there have been over 2,000 confirmed cases across 27 countries. There is currently no available vaccine.

As MERS-CoV, which is transmitted from camels to humans, is identified as a priority disease by the World Health Organization, there is an urgent need for new vaccine technology against the pathogen, Academia Sinica said.

The international research team is led by the UTMB's Kent Tseng, NTU's Chen Hui-wen (陳慧文) and Hu.

The paper presenting the results, titled "Viromimetic STING agonist-loaded hollow polymeric nanoparticles for safe and effective vaccination against Middle East respiratory syndrome coronavirus," was published online April 11 in the journal Advanced Functional Materials.