Antiviral activity of the human endogenous retrovirus-R envelope protein against SARS-CoV-2

Coronavirus-induced disease-19 (COVID-19), caused by SARS-CoV-2, is still a major global health challenge. Human endogenous retroviruses (HERVs) represent retroviral elements that were integrated into the ancestral human genome. HERVs are important in embryonic development as well as in the manifestation of diseases, including cancer, inflammation, and viral infections. Here, we analyze the expression of several HERVs in SARS-CoV-2-infected cells and observe increased activity of HERV-E, HERV-V, HERV-FRD, HERV-MER34, HERV-W, and HERV-K-HML2. In contrast, the HERV-R envelope is downregulated in cell-based models and PBMCs of COVID-19 patients. Overexpression of HERV-R inhibits SARS-CoV-2 replication, suggesting its antiviral activity. Further analyses demonstrate the role of the extracellular signal-regulated kinase (ERK) in regulating HERV-R antiviral activity. Lastly, our data indicate that the crosstalk between ERK and p38 MAPK controls the synthesis of the HERV-R envelope protein, which in turn modulates SARS-CoV-2 replication. These findings suggest the role of the HERV-R envelope as a prosurvival host factor against SARS-CoV-2 and illustrate a possible advantage of integration and evolutionary maintenance of retroviral elements in the human genome.Copyright © 2023 The Authors.

Red Blood Cell-Derived Nanoerythrosomes Mediated Efficient Delivery Of Mrna Vaccine Candidate Against COVID-19

Introduction: The COVID-19 pandemic has been a major public health concern throughout the world. Various ventures of vaccine candidates are being studied rigorously in this regard and one such candidate is the receptor binding domain (RBD) of spike protein which interacts with angiotensin converting enzyme 2 (ACE2) on the host cell's membrane. Exploiting this interaction, many scientists across the world attempted to develop mRNA vaccine against SARSCoV- 2. A major lacuna associated with mRNA vaccines is their delivery through a suitable carrier, especially given the stability issues associated with mRNA vaccines. Aims & Objectives: The aim of our research is to develop an efficient mode of delivery of the self-amplifying mRNA (saRNA) against COVID 19. We have developed small vesicles from erythrocyte ghosts, known as nanoerythrosomes, which are in the nanometre range and focussed on development of nanoerythrosomes for delivery of mRNA-based vaccines. Material(s) and Method(s): Nanoerythrosomes were prepared from erythrocytes using osmotic and ultrasonic frequency stress and loaded with saRNA vaccine candidate. Thereafter, the nanoerythrosomes were characterized using Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) to confirm their homogeneity, integrity and size. The mRNA loaded nanoerythrosomes were used to deliver the mRNA in Vero E6 cells to evaluate its uptake. Result(s): The characterization of nanoerythrosomes using DLS and TEM revealed their size in the range of 100-200 nm. The delivery mediated by nanoerythrosomes was comparable to the Lipofectamine mediated uptake of saRNA indicating the excellent delivery efficacy of nanoerythrosomes. The added advantage of nanoerythrosomes mediated delivery is that they are rapidly taken up from blood by macrophages of the reticuloendothelial system (RES) that is present in liver, lung, and spleen. Thus the combination of saRNA and nanoerythrosomes can accelerate the uptake and antigen presentation in reticuloendothelial system and will provide an outstanding platform for the development of SARS-CoV2 vaccine. Conclusion(s): We developed a new approach to deliver mRNA vaccine candidates using nanoerythrosomes and successfully demonstrate its efficacy in vitro. This strategy can be further extended for the delivery of other vaccine candidates. (Figure Presented).

The South African Public School System, Education In Crisis: A Review of Our COVID19 Response

COVID-19 has disproportionately impacted the world's poorest communities and highlighted several systemic imbalances, leaving nations vulnerable and destitute. Taking a worldwide perspective on the influence on the right to education, this article analyzes how the South African education systems responded to the COVID-19 pandemic. As we swiftly transition to distance education, we must also ensure that we are not caught off guard again. Education systems worldwide must begin long-term planning and construction of distance education systems in order to be prepared for the inevitable next emergency. If COVID-19 teaches us anything, it is that distance education cannot be a 'nice to have' supplement to the existing educational system;it must be a 'must have,' integrated, and indispensable component of the total educational system. The findings indicated that governments have an uneven capacity for responding to and preparing for the learning losses associated with school closures. We concluded that it is critical to articulate inclusive educational policies that support strengthening the government's response capacity, particularly in terms of access to technology, electricity, connectivity, ICT devices, learning materials and technology adapted curriculum and educator training all in addressing the countries response to educational crisis and eventually embracing the opportunity of stirring the education sector into the fourth industrial revolution. © 2021 IEEE.