Characterization of amino acid substitutions in feline coronavirus 3C-like protease from a cat with feline infectious peritonitis treated with a protease inhibitor

Abstract

Feline infectious peritonitis (FIP) is a highly fatal disease caused by a virulent feline coronavirus in domestic and wild cats. We have previously reported the synthesis of potent coronavirus 3C-like protease (3CLpro) inhibitors and the efficacy of a protease inhibitor, GC376, in client-owned cats with FIP. In this study, we studied the effect of the amino acid changes in 3CLpro of feline coronavirus from a feline patient who received antiviral treatment for prolonged duration. We generated recombinant 3CLpro containing the identified amino acid changes (N25S, A252S or K260 N) and determined their susceptibility to protease inhibitors in the fluorescence resonance energy transfer assay. The assay showed that N25S in 3CLpro confers a small change (up to 1.68-fold increase in the 50% inhibitory concentration) in susceptibility to GC376, but other amino acid changes do not affect susceptibility. Modelling of 3CLpro carrying the amino acid changes was conducted to probe the structural basis for these findings. The results of this study may explain the observed absence of clinical resistance to the long-term antiviral treatment in the patients.

A Tale of Two Viruses: The Distinct Spike Glycoproteins of Feline Coronaviruses

“…[13]. While remaining a devastating disease in cat populations, recent reports describing the role of nucleoside analogs and protease inhibitors, and their potential as a treatment for FCoV infection have raised the possibility of preventing lethal FIP [15][16][17][18].…”

Development of Feline Ileum- and Colon-Derived Organoids and Their Potential Use to Support Feline Coronavirus Infection

“…FIPV emerges through mutations from the harmless FECV and can lead to a fatal clinical condition known as feline infectious peritonitis (FIP) [ 5 , 6 , 7 , 8 , 9 ]. Although the molecular pathogenesis of FIP is poorly understood [ 10 , 11 , 12 ], promising therapeutical approaches have recently been described [ 13 , 14 , 15 , 16 , 17 , 18 ]. It is important to note that both biotypes exist in two serotypes [ 19 , 20 , 21 ].…”

Current status of antivirals and druggable targets of SARS CoV-2 and other human pathogenic coronaviruses

“… Favipiravir K159R CVB3 K545 n.a. 3CL-PR GRL-001 T26I MHV T26 3.06 c Deng et al (2014) D65G MHV N65 2.56 c T26I MHV + D65G MHV T26+N65 >6 c T26I MHV + A298D MHV T26+S301 >6 c GC376 N25S Fel-Cov T25 1.38 Perera et al (2019) A252S Fel-Cov A255 1.15 K260N Fel-Cov D263 1.05 N25S Fel-Cov + K260N Fel-Cov T25+D263 1.53 N25S FelCov + A252S FelCov + K260N Fel-Cov T25+A255+D263 1.68 Abbreviations: RdRp, RNA-dependent RNA polymerase; 5-FU, 5-fluorouracil; 5-AZC, 5-azacytidine; 3CL-PR, 3CL protease; MHV, murine hepatitis virus; SARS-CoV-1, severe acute respiratory syndrome coronavirus; PV, poliovirus; CVB3, Coxsackievirus B3; FelCov, feline coronavirus. a The column reports the drug-resistance mutations identified for each antiviral drug.…”

“…Recent reports described the effects of specific 3CL-PR mutations (N25S, A252S and K260 N) emerging in a patient with acquired feline infectious peritonitis receiving prolonged treatment with the 3CL-PR inhibitor GC376 ( Pedersen et al, 2018 ; Perera et al, 2019 ). Considering single (N25S, A252S or K260 N), double (N25S + K260 N) or triple (N25S + A252S + K260 N) amino acid changes, only those containing N25S where associated with a marginal reduction in susceptibility to GC376 ( Perera et al, 2019 ). Conversely, drug resistance profiles to lopinavir, used in clinical practice for the treatment of SARS-CoV-2 infected patients have not yet been defined.…”