Search

Although ACE2 is the primary receptor for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, a systematic assessment of host factors that regulate binding to SARS-CoV-2 spike protein has not been described. Here, we use whole-genome CRISPR activation to identify host factors controlling cellular interactions with SARS-CoV-2. Our top hit was a TLR-related cell surface receptor called leucine-rich repeat-containing protein 15 (LRRC15). LRRC15 expression was sufficient to promote SARS-CoV-2 spike binding where they form a cell surface complex. LRRC15 mRNA is expressed in human collagen-producing lung myofibroblasts and LRRC15 protein is induced in severe Coronavirus Disease 2019 (COVID-19) infection where it can be found lining the airways. Mechanistically, LRRC15 does not itself support SARS-CoV-2 infection, but fibroblasts expressing LRRC15 can suppress both pseudotyped and authentic SARS-CoV-2 infection in trans. Moreover, LRRC15 expression in fibroblasts suppresses collagen production and promotes expression of IFIT, OAS, and MX-family antiviral factors. Overall, LRRC15 is a novel SARS-CoV-2 spike-binding receptor that can help control viral load and regulate antiviral and antifibrotic transcriptional programs in the context of COVID-19 infection.

CRM adoption can provide innumerable benefits to the SMEs performance, including solving customer problems in a timely manner, enhancing customer satisfaction by appointing an expert to solve issues and queries, and the like. This study aims to examine the moderating effects of the firm size in the adoption of CRM in the Palestinian SMEs. A quantitative approach was used to investigate the relationships between the variables, which are compatibility, IT infrastructure, complexity, relative advantage, security, top management support, customer pressure, and competitive pressure. A questionnaire was designed to collect data from 420 SMEs in Palestine. A total of 331 respondents completed and returned the survey. The Partial Least Square-Structural Equation Model (PLS-SEM) approach was used to assess both the measurement and structural models. The Diffusion of Innovation Theory (DOI) and Technology, Organization, and Environment Framework (TOE) framework were employed to identify the determinant factors from the technological, organizational, and environmental perspectives. The findings and conclusions of this study provide show that the moderating effect of firm size has significant effect compatibility, top management support, customer pressure, and IT infrastructure factors.