The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein mediates virus entry by binding to the host cell receptor, human angiotensin converting enzyme 2 (hACE2), and catalyzing virus–host membrane fusion. The S protein also mediates cell–cell fusion, potentially allowing the virus to spread virion-independently. Here, we compared the fusogenicity of SARS-CoV-2 variant S proteins using a cell–cell fusion assay. In cells overexpressing hACE2, cell–cell fusion ability of all tested SARS-CoV-2 variants was similar to that of the Wuhan-Hu-1 strain. However, in cells with endogenous hACE2, SARS-CoV-2 variants, especially the Delta variant, stimulated significantly greater cell–cell fusion than the original strain. Our results showed that the Delta variant S protein is highly fusogenic and can spread rapidly by utilizing small amounts of hACE2.
Since the outbreak of coronavirus disease 2019 (COVID-2019), the infection has spread worldwide due to the highly contagious nature of severe acute syndrome coronavirus (SARS-CoV-2). To manage SARS-CoV-2, the development of diagnostic assays that can quickly and accurately identify the disease in patients is necessary. Currently, nucleic acid-based testing and serology-based testing are two widely used approaches. Of these, nucleic acid-based testing with quantitative reverse transcription-PCR (RT-qPCR) using nasopharyngeal (NP) and/or oropharyngeal (OP) swabs is considered to be the gold standard. Recently, the use of saliva samples has been considered as an alternative method of sample collection. Compared to the NP and OP swab methods, saliva specimens have several advantages. Saliva specimens are easier to collect. Self-collection of saliva specimens can reduce the risk of infection to healthcare providers and reduce sample collection time and cost. Until recently, the sensitivity and accuracy of the data obtained using saliva specimens for SARS-CoV-2 detection was controversial. However, recent clinical research has found that sensitive and reliable data can be obtained from saliva specimens using RT-qPCR, with approximately 81% to 95% correspondence with the data obtained from NP and OP swabs. These data suggest that self-collected saliva is an alternative option for the diagnosis of COVID-19.
식중독 원인균 S. aureus, E. coli O157:H7, S. typhimurium, S. enteritidis, L. monocytogenes, 장티프스 원인균 S. typhi, 패혈증 원인균 V. parahaemolyticus, 세균성 이질 원인균 S. sonnei를 20℃에서 30분간 그린존^TM과 접촉시킨 결과 최소 3배 희석액부터 최대 24배 희석액에서 균에 대한 살멸 효과를 나타내었다. 그린존^TM 3배 희석액을 이용하여 30초, 1부, 5분간 균과 접촉시킨 결과 S. aureus만 제외하고 모두 30초에 100% 살멸하는 효과를 나타내었다. 그린존^TM을 이용하여 사스의 원인체와 동일한 바이러스인 코로나 바이러스에 대한 살바이러스 효과를 본 결과 제품의 5배 희석액까지 유효한 살바이러스 효과를 보였다. 사람과 접촉이 많은 애완견 바이러스인 파보바이러스(CPV), 디스템퍼바이러스(CDV)에 대하여 시험한 결과 유기물과 경수 등의 악조건에서도 바이러스를 살멸하는 효과를 나타내었다. 그린존^TM을 이용한 회와 냉장육 등에서의 적용 시험결과 미생물 생육이 현저히 저해됨을 알 수 있었다. 체소내의 미생물에 대한 살멸효과 시험에서도 미생물의 수가 현저하게 감소하였고, 특히 대장균의 수가 현저하게 감소하였다. 그린존^TM은 세균, 바이러스의 살멸에 탁월한 효과를 보이며, 음식물에 직접 처리할 시에도 그 안전성과 효능이 입증되었다.