Cytokine systems approach demonstrates differences in innate and pro-inflammatory host responses between genetically distinct MERS-CoV isolates

Selinger, Christian; Tisoncik-Go, Jennifer; Menachery, Vineet D; Agnihothram, Sudhakar; Law, G Lynn; Chang, Jean; Kelly, Sara M; Sova, Pavel; Baric, Ralph S; Katze, Michael G

Middle East respiratory syndrome coronavirus (MERS-CoV) is the etiologic agent of an ongoing respiratory disease outbreak that emerged in Saudi Arabia in 2012. MERS-CoV is most closely related to Tylonycteris bat coronavirus HKU4 and Pipistrellus bat coronavirus HKU5 [1] , highlighting the ever present threat of zoonotic transmission of novel pathogenic coronaviruses. Middle East respiratory syndrome (MERS) resembles acute respiratory disease syndrome (ARDS) caused by severe acute respiratory disease syndrome coronavirus (SARS-CoV) in 2002 and 2003, with some MERS patients exhibiting progressive respiratory distress and renal failure [1, 2] . Despite similarities in overt clinical disease, MERS-CoV is distinct from SARS-CoV in that the virus utilizes a different cellular receptor, dipeptidyl peptidase-4 (DPP4) [3] , and exhibits an expanded host cell tropism, readily replicating in a variety of human lung cell types including fibroblasts, microvascular endothelial cells, and type II pneumocytes [4] .