Lipid nanoparticle-encapsulated mRNA antibody provides long-term protection against SARS-CoV-2 in mice and hamsters.

Monoclonal antibodies represent important weapons in our arsenal to against the COVID-19 pandemic. However, this potential is severely limited by the time-consuming process of developing effective antibodies and the relative high cost of manufacturing. Herein, we present a rapid and cost-effective lipid nanoparticle (LNP) encapsulated-mRNA platform for in vivo delivery of SARS-CoV-2 neutralization antibodies. Two mRNAs encoding the light and heavy chains of a potent SARS-CoV-2 neutralizing antibody HB27, which is currently being evaluated in clinical trials, were encapsulated into clinical grade LNP formulations (named as mRNA-HB27-LNP). In vivo characterization demonstrated that intravenous administration of mRNA-HB27-LNP in mice resulted in a longer circulating half-life compared with the original HB27 antibody in protein format. More importantly, a single prophylactic administration of mRNA-HB27-LNP provided protection against SARS-CoV-2 challenge in mice at 1, 7 and even 63 days post administration. In a close contact transmission model, prophylactic administration of mRNA-HB27-LNP prevented SARS-CoV-2 infection between hamsters in a dose-dependent manner. Overall, our results demonstrate a superior long-term protection against SARS-CoV-2 conferred by a single administration of this unique mRNA antibody, highlighting the potential of this universal platform for antibody-based disease prevention and therapy against COVID-19 as well as a variety of other infectious diseases.

Transcriptomic analysis reveals novel mechanisms of SARS-CoV-2 infection in human lung cells.

BACKGROUND: Severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2) is a single-stranded RNA virus responsible for the global pandemic of the coronavirus disease-2019 (COVID-19). To date, there are still no effective approaches for the prevention and treatment of COVID-19. OBJECTIVE: The present study aims to explore the possible mechanisms of SARS-CoV-2 infection in human lung cells. METHODS: Data interpretation was conducted by recruiting bioinformatics analysis, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways analysis using downloaded data from the NCBI Gene Expression Omnibus database. RESULTS: The present study demonstrated that SARS-CoV-2 infection induces the upregulation of 14 interferon-stimulated genes, indicative of immune, and interferon responses to the virus. Notably, genes for pyrimidine metabolism and steroid hormone biosynthesis are selectively enriched in human lung cells after SARS-CoV-2 infection, suggesting that altered pyrimidine metabolism and steroid biosynthesis are remarkable, and perhaps druggable features after SARS-CoV-2 infection. Besides, there is a strong positive correlation between viral ORF1ab, ORF6, and angiotensin-converting enzyme 2 (ACE2) expression in human lung cells, implying that ACE2 facilitates SARS-CoV-2 infection and replication in host cells probably through the induction of ORF1ab and ORF6.

A Thermostable mRNA Vaccine against COVID-19.

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.

Exploring an Integrative Therapy for Treating COVID-19: A Randomized Controlled Trial.

OBJECTIVES: To develop a new Chinese medicine (CM)-based drug and to evaluate its safety and effect for suppressing acute respiratory distress syndrome (ARDS) in COVID-19 patients. METHODS: A putative ARDS-suppressing drug Keguan-1 was first developed and then evaluated by a randomized, controlled two-arm trial. The two arms of the trial consist of a control therapy (alpha interferon inhalation, 50 µg twice daily; and lopinavir/ritonavir, 400 and 100 mg twice daily, respectively) and a testing therapy (control therapy plus Keguan-1 19.4 g twice daily) by random number table at 1:1 ratio with 24 cases each group. After 2-week treatment, adverse events, time to fever resolution, ARDS development, and lung injury on newly diagnosed COVID-19 patients were assessed. RESULTS: An analysis of the data from the first 30 participants showed that the control arm and the testing arm did not exhibit any significant differences in terms of adverse events. Based on this result, the study was expanded to include a total of 48 participants (24 cases each arm). The results show that compared with the control arm, the testing arm exhibited a significant improvement in time to fever resolution (P=0.035), and a significant reduction in the development of ARDS (P=0.048). CONCLUSIONS: Keguan-1-based integrative therapy was safe and superior to the standard therapy in suppressing the development of ARDS in COVID-19 patients. (Trial registration No. NCT04251871 at www.clinicaltrials.gov ).

[Rapid establishment of traditional Chinese medicine prevention and treatment of 2019-nCoV based on clinical experience and molecular docking].

The coronavirus disease 2019(COVID-19) is raging in China and more than 20 other countries and regions since the middle of December 2019. Currently, there is no specific drug or vaccine besides symptomatic supportive therapy. Taking full advantage of the clinical experience of traditional Chinese medicine(TCM) in preventing and controlling major epidemics such as SARS, it is an important mission for TCM to propose effective formula with immediate response and solid evidence by using modern biomedical knowledge and techniques(molecular docking assisted TCM formulation for short). In view of the high homology between the gene sequences of the novel coronavirus and SARS virus, and the similarities between the two in terms of pathogenic mechanism and clinical manifestations, our team established a rapid screening and optimization model for the prevention and treatment of the novel coronavirus based on clinical experience and molecular docking technology. Firstly, the clinical team and the research team pre-developed and screened TCM formula by using "back-to-back" manner. Then, the formula was optimized and determined by comparing and analyzing the results of the two groups. The results showed that the research team screened out 46 active ingredients from candidate TCMs that could act on the novel coronavirus S-protein-binding site of human ACE2 protein, which were mainly attributed to 7 herbs such as Lonicerae Japonicae Flos and Mori Folium. The result was largely consistent with the formula raised by the clinical group, verifying and supporting its rationality. This provides evidence for the scientific and potential efficacy of the TCM prescription from the perspective of treatment target analysis, and also suggests that the TCM prescription has the potential to directly inhibit viral infection in addition to improving clinical symptoms or syndromes. Based on this, our team optimized and formed a new anti-coronavirus TCM prescription "Keguan Yihao", immediately providing the TCM prescription with certain clinical experience and objective evidence support for the prevention and treatment of new emergent infectious diseases in our hospital. The TCM prescription was combined with modern medicine symptomatic supportive treatment for clinical treatment, preliminary results showed better effect than symptomatic supportive therapy alone. This research has innovated the method mode in clinical practice and basic research integration of traditional Chinese medicine for the prevention and control of new emerging infectious diseases. It is of great significance to further improve the rapid response mechanism of TCM in face of major epidemics, and further improve the capability level of TCM to prevent and treat new emerging infectious diseases.