What Have We Learned About Middle East Respiratory Syndrome Coronavirus Emergence in Humans? A Systematic Literature Review

Dawson, Patrick; Malik, Mamunur Rahman; Parvez, Faruque; Morse, Stephen S.

One challenge to overcome is the effect of the virus on host defenses. A caveat is that much of this research (although not all) has been done in vitro and may not necessarily be comparable with the immunological results described above in patients. MERS-CoV has been reported to inhibit host innate immunity . Impaired IFN and cytokine responses may mediate some of these effects, based on assays on cells from MERS patients (Faure et al. 2014 , Scheuplein et al. 2015 , although the numbers of patients were small. In vitro studies have shown that MERS-CoV could downregulate expression of IFN-stimulated gene subsets , chemokines (Mielech et al. 2014) , and IFN-b. Another study found that MERS-CoV may cause delayed induction of proinflammatory cytokines together with suppression of the host's innate antiviral response .