Feline infectious peritonitis (FIP) is a fatal disease in domestic and nondomestic felids caused by feline coronavirus (FCoV). Currently, no effective vaccine is available for the prevention of this disease. In searching for agents that may prove clinically effective against FCoV infection, 16 compounds were screened for their antiviral activity against a local FCoV strain in Felis catus whole fetus-4 cells. The results showed that Galanthus nivalis agglutinin (GNA) and nelfinavir effectively inhibited FCoV replication. When the amount of virus preinoculated into the test cells was increased to mimic the high viral load present in the target cells of FIP cats, GNA and nelfinavir by themselves lost their inhibitory effect. However, when the two agents were added together to FCoV-infected cells, a synergistic antiviral effect defined by complete blockage of viral replication was observed. These results suggest that the combined use of GNA and nelfinavir has therapeutic potential in the prophylaxis and treatment of cats with early-diagnosed FIP.

SARS-Coronavirus-2 (SARS-CoV-2) causes Coronavirus disease 2019 , an infectious respiratory disease causing thousands of deaths and overwhelming public health systems. The international spread of SARS-CoV-2 is associated with the ease of global travel, and societal dynamics, immunologic naiveté of the host population, and muted innate immune responses. Based on these factors and the expanding geographic scale of the disease, the World Health Organization (WHO) declared the COVID-19 outbreak a pandemicthe first caused by a coronavirus. In this review, we summarize the current epidemiological status of COVID-19 and consider the virological and immunological lessons, animal models, and tools developed in response to prior SARS-CoV and MERS-CoV outbreaks that can serve as resources for development of SARS-CoV-2 therapeutics and vaccines. In particular, we discuss structural insights into the SARS-CoV-2 spike protein, a major determinant of transmissibility, and discuss key molecular aspects that will aid in understanding and fighting this new global threat. The COVID-19 Pandemic to DateFrom Emergence in Wuhan to Global Pandemic In December 2019, a novel human coronavirus (HCoV) was identified as the causative agent of clusters of pneumonia in China. The virus was named as SARS-CoV-2, based on its phylogenetic and taxonomic similarity to SARS-CoV [1], which caused an outbreak of severe acute respiratory syndrome (SARS) in 2002. The WHO named the disease caused by SARS-CoV-2 as coronavirus disease 2019 . The first confirmed SARS-CoV-2 case was found in Wuhan, China (Figure 1A). Subsequently, medical workers and family clusters who had not visited Wuhan tested positive for SARS-CoV-2, thus confirming human-to-human transmission [2]. SARS-CoV-2 rapidly spread to most countries and has resulted in thousands of fatalities (Figure 1B-D). WHO declared a pandemic on 11 March 2020. As of 5 May 2020, over 3 500 000 cases have been confirmed in over 185 countries, with over 243 000 deaths, suggesting a case fatality rate (CFR) of 6.9% (WHO report 106) (Figure 1B-D). However, nominal CFR are strongly influenced by the extent of testing of suspected cases and under-testing can result in higher apparent CFR. In this review, we summarize current progress in epidemiology and detection methods for SARS-CoV-2 and discuss findings concerning general characteristics of pathogenic coronaviruses. These studies form the foundation for future efforts to develop vaccines and preand postexposure therapeutics.

Feline infectious peritonitis (FIP) is an immune-mediated, highly lethal disease caused by feline coronavirus (FCoV) infection. Currently, no protective vaccine or effective treatment for the disease is available. Studies have found that some cats survive the challenge of virulent FCoV isolates. Since cellular immunity is thought to be critical in preventing FIP and because diseased cats often show a significant decrease in interferon-γ (IFN-γ) production, we investigated whether single nucleotide polymorphisms (SNP) in the feline IFN-γ gene (fIFNG) are associated with the outcome of infection. A total of 82 asymptomatic and 63 FIP cats were analyzed, and 16 SNP were identified in intron 1 of fIFNG. Among these SNP, the fFING + 428 T allele was shown to be a FIP-resistant allele (p = 0.03), and the heterozygous genotypes 01C/T and +408C/T were found to be FIP-susceptible factors (p = 0.004). Furthermore, an fIFNG + 428 resistant allele also showed a clear correlation with the plasma level of IFN-γ in FIP cats. For the identification of these three FIP-related SNP, genotyping methods were established using amplification refractory mutation system PCR (ARMS-PCR) and restriction fragment length polymorphisms (RFLP), and the different genotypes could easily be identified without sequencing. The identification of additional FIP-related SNP will allow the selection of resistant cats and decrease the morbidity of the cat population to FIP.

Recurrent respiratory papillomatosis (RRP) is mainly caused by human papillomavirus (HPV) 6 and 11. While various adjuvant therapies have been reported, no effective therapy has been documented to universally "cure" this disease. In the era of precision medicine, it would be valuable to identify effective intervention based on drug sensitivity testing and/or molecular analysis. It is essential to be able to successfully carry out in vitro culture and expand tumor cells directly from patients to accomplish this goal. Here we report the result of successful culture of HPV-infected cell lines (success rate 70%, 9/13) that express the E6/E7 RNA transcript, using pathologic tissue biopsies from patients treated at our institution. The availability of such a system would enable ex vivo therapeutic testing and disease modeling.