Inhibition of endocytic pathways impacts cytomegalovirus maturation

Endocytic processes are critical for cellular entry of several viruses; however, the role of endocytosis in cellular trafficking of viruses beyond virus entry is only partially understood. Here, we utilized two laboratory strains (AD169 and Towne) of human cytomegalovirus (HCMV), which are known to use cell membrane fusion rather than endocytosis to enter fibroblasts, in order to study a post-entry role of endocytosis in HCMV life cycle. Upon pharmacological inhibition of dynamin-2 or clathrin terminal domain (TD) ligand association, these strains entered the cells successfully based on the expression of immediate early viral protein. However, both the inhibitors significantly reduced the growth rates and final virus yields of viruses without inhibiting the expression of early to late viral proteins. Clathrin accumulated in the cytoplasmic virus assembly compartment (vAC) of infected cells co-localizing with virus tegument protein pp150 and the formation of vAC was compromised upon endocytic inhibition. Transmission electron micrographs (TEM) of infected cells treated with endocytosis inhibitors showed intact nuclear stages of nucleocapsid assembly but the cytoplasmic virus maturation was greatly compromised. Thus, the data presented here implicate endocytic pathways in HCMV maturation and egress.American Heart Association Scientist Development Grant [14SDG20390009]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

COVID-19 related Awareness among Healthcare Professionals and Students at the Medical Center in the Southern United States

Background: In late 2019, the novel COVID-19 was reported to cause severe viral pneumonia in Wuhan, China. It has spread worldwide, resulting in a pandemic that has now infected more than 123 million people, causing more than 2.7 million deaths globally. Mississippi has become one of the hotspots for spreading the virus with a very high positivity rate. As of 6/09/2021, there were a total of 318,685 cases, and 7,347 deaths have been reported in Mississippi.Purpose: This study aimed to assess the COVID-19 related knowledge among faculty and staff working in our healthcare system. We also assessed if there are any gender differences in COVID-19 related knowledge.Methods: Approval for this cross-sectional study was obtained from our institutional review board at the University of Mississippi Medical Center (UMMC). A convenience sample of staff members, students, and residents at the medical center in the southern United States was invited to complete an online survey. The data were collected from September 29 to October 16, 2020. We asked participants to report demographics (age, gender, and profession), COVID-19 related knowledge (15 questions), received hand hygiene training (one question), and whether they would choose to receive COVID 19 vaccine if made available in the future (one question). SPSS 26 was used to conduct statistical analysis. Descriptive statistics were calculated for all the variables. Chi-Square, one-way analysis of variance, independent samples t-test were conducted, as appropriate. A p-value of \u3c 0.05 was considered statistically significant for all the analyses. Results: A total of 750 individuals completed the study questionnaire. Overall, respondents reported a mean score of 10.03 (standard deviation = 1.06, range 5-13) on the knowledge questions. About one-fourth (26.8%) reported that they had not received any formal training in hand hygiene in the last three years. In addition, almost as many participants (24.3%) indicated that they would not choose to receive the COVID vaccine in the future. Upon analysis, the question, “Use of a face mask is essential in which of the following groups?” was answered incorrectly by more males (7.4%) than females (2.2%; p=0.001). The question, “Is COVID a hoax ?” was also answered incorrectly by more male (3.0%) compared to female participants (0.7%; p=0.018). It was also found that when participants were asked, “If a proven safe and effective COVID vaccine were made available to you in the future, would you choose to receive the vaccine?” there was a statistical greater difference of “No” responses in females (28.1%) compared to the male counterparts (13.4%; p \u3c 0.001). Conclusion: There is a noticeable gap in knowledge among different age groups. Our institution and others alike around the United States should provide mandatory education sessions regarding the novel COVID virus. The gender differences in COVID awareness responses show that educational awareness should be tailored towards different genders

The degree of polymerization and sulfation patterns in heparan sulfate are critical determinants of cytomegalovirus entry into host cells.

Several enveloped viruses, including herpesviruses attach to host cells by initially interacting with cell surface heparan sulfate (HS) proteoglycans followed by specific coreceptor engagement which culminates in virus-host membrane fusion and virus entry. Interfering with HS-herpesvirus interactions has long been known to result in significant reduction in virus infectivity indicating that HS play important roles in initiating virus entry. In this study, we provide a series of evidence to prove that specific sulfations as well as the degree of polymerization (dp) of HS govern human cytomegalovirus (CMV) binding and infection. First, purified CMV extracellular virions preferentially bind to sulfated longer chain HS on a glycoarray compared to a variety of unsulfated glycosaminoglycans including unsulfated shorter chain HS. Second, the fraction of glycosaminoglycans (GAG) displaying higher dp and sulfation has a larger impact on CMV titers compared to other fractions. Third, cell lines deficient in specific glucosaminyl sulfotransferases produce significantly reduced CMV titers compared to wild-type cells and virus entry is compromised in these mutant cells. Finally, purified glycoprotein B shows strong binding to heparin, and desulfated heparin analogs compete poorly with heparin for gB binding. Taken together, these results highlight the significance of HS chain length and sulfation patterns in CMV attachment and infectivity