Immunization with inactivated Middle East Respiratory Syndrome coronavirus vaccine leads to lung immunopathology on...

Area of Science:

• Immunology
• Virology
• Pathology

Background:

• Previous studies indicated that inactivated SARS-CoV vaccines induced hypersensitive lung pathology in mice.
• Middle East Respiratory Syndrome Coronavirus (MERS-CoV) poses a significant public health threat.

Purpose of the Study:

• To investigate if inactivated MERS-CoV vaccines induce similar hypersensitive lung pathology as observed with SARS-CoV vaccines.
• To assess the immune response and lung pathology following MERS-CoV challenge in vaccinated mice.

Main Methods:

• Mice were vaccinated with an inactivated MERS-CoV vaccine, with and without adjuvant.
• Vaccinated and control mice were challenged with infectious MERS-CoV.
• Lung pathology, including cellular infiltrates and cytokine levels (IL-5, IL-13), was analyzed.

Main Results:

• The inactivated MERS-CoV vaccine induced neutralizing antibodies and reduced lung viral load post-challenge.
• All challenged groups exhibited lung mononuclear infiltrates.
• Vaccine groups showed increased eosinophilic infiltrates and elevated levels of IL-5 and IL-13.

Conclusions:

• Inactivated MERS-CoV vaccines may carry a risk of hypersensitive-type lung pathology upon MERS-CoV infection.
• This risk appears similar to that observed with inactivated SARS-CoV vaccines.
• Further research is warranted to understand and mitigate this potential adverse effect.