A Novel Conserved Linear Neutralizing Epitope on the Receptor-Binding Domain of the SARS-CoV-2 Spike Protein.

The continuous emergence of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made it challenging to develop broad-spectrum prophylactic vaccines and therapeutic antibodies. Here, we have identified a broad-spectrum neutralizing antibody and its highly conserved epitope in the receptor-binding domain (RBD) of the spike protein (S) S1 subunit of SARS-CoV-2. First, nine monoclonal antibodies (MAbs) against the RBD or S1 were generated; of these, one RBD-specific MAb, 22.9-1, was selected for its broad RBD-binding abilities and neutralizing activities against SARS-CoV-2 variants. An epitope of 22.9-1 was fine-mapped with overlapping and truncated peptide fusion proteins. The core sequence of the epitope, 405D(N)EVR(S)QIAPGQ414, was identified on the internal surface of the up-state RBD. The epitope was conserved in nearly all variants of concern of SARS-CoV-2. MAb 22.9-1 and its novel epitope could be beneficial for research on broad-spectrum prophylactic vaccines and therapeutic antibody drugs. IMPORTANCE The continuous emergence of new variants of SARS-CoV-2 has caused great challenge in vaccine design and therapeutic antibody development. In this study, we selected a broad-spectrum neutralizing mouse monoclonal antibody which recognized a conserved linear B-cell epitope located on the internal surface of RBD. This MAb could neutralize all variants until now. The epitope was conserved in all variants. This work provides new insights in developing broad-spectrum prophylactic vaccines and therapeutic antibodies.

Recovery of a patient with severe COVID-19 by acupuncture and Chinese herbal medicine adjuvant to standard care.

There is currently no drug or therapy that can cure the coronavirus disease 2019 (COVID-19), which is highly contagious and can be life-threatening in severe cases. Therefore, seeking potential effective therapies is an urgent task. An older female at the Leishenshan Hospital in Wuhan, China, with a severe case of COVID-19 with significant shortness of breath and decrease in peripheral oxygen saturation (SpO2), was treated using manual acupuncture and Chinese herbal medicine granule formula Fuzheng Rescue Lung with Xuebijing Injection in addition to standard care. The patient's breath rate, SpO2, heart rate, ratio of neutrophil/lymphocyte (NLR), ratio of monocyte/lymphocyte (MLR), C-reactive protein (CRP), and chest computed tomography were monitored. Acupuncture significantly improved the patient's breathing function, increased SpO2, and decreased her heart rate. Chinese herbal medicine might make the effect of acupuncture more stable; the use of herbal medicine also seemed to accelerate the absorption of lung infection lesions when its dosage was increased. The combination of acupuncture and herbs decreased NLR from 14.14 to 5.83, MLR from 1.15 to 0.33 and CRP from 15.25 to 6.01 mg/L. These results indicate that acupuncture and Chinese herbal medicine, as adjuvants to standard care, might achieve better results in treating severe cases of COVID-19.

Quantifying Spatiotemporal Changes in Human Activities Induced by COVID-19 Pandemic Using Daily Nighttime Light Data.

The COVID-19 pandemic caused drastic changes in human activities and nighttime light (NTL) at various scales, providing a unique opportunity for exploring the pattern of the extreme responses of human community. This study used daily NTL data to examine the spatial variations and temporal dynamics of human activities under the influence of COVID-19, taking Chinese mainland as the study area. The results suggest that the change in the intensity of NTL is not correlated to the number of confirmed cases, but reflects the changes in human activities and the intensity of epidemic prevention and control measures within a region. During the outbreak period, the major provincial capitals and urban agglomerations were affected by COVID-19 more than smaller cities. During the recovery, different regions showed different recovery processes. The cities in West and Northeast China recovered steadily while the recovery in coastal cities showed relatively greater fluctuations due to an increase in imported cases. Wuhan, the most seriously affected city in China, did not recover until the end of March. Nevertheless, as of 31 March, the overall NTL across China had recovered to an 89.5% level of the same period in the previous year. The high consistency between the big data of travel intensity and NTL further proved the validity of the results of this study. These findings imply that daily NTL data are effective for rapidly monitoring the dynamic changes in human activities, and can help evaluate the effects of control measures on human activities during major public health events.

Experience of the use of hydroxychloroquine on patients with COVID-19: A perspective on viral load and cytokine kinetics.

Until now, there are no approved treatment against COVID-19. Hydroxychloroquine (HCQ) was hypothesized to be active against SARS-CoV2 via antiviral and anti-inflammatory effect; however, HCQ for COVID-19 in clinical use remained debating. In this preliminary report, we presented six patients with mild to moderate COVID-19. They were treated with HCQ for 14 days from the day of COVID-19 diagnosis. Serial viral load from respiratory specimens were performed every other day. Cytokine profile was checked before HCQ initiation and on the 14th day of HCQ treatment. All patients receiving HCQ completed 14-day course without complication. Among the six patients, the mean duration from symptom onset to last detectable viral load was 34 ± 12 days, which was similar to those without specific treatment in previous reports. Low level of interferon-gamma was noted in all patients of different stage of infection and three patients had elevation of IL-17 level. Prolonged virus shedding is still observed regardless HCQ. The impact of HCQ on cytokine kinetics remained unclear; however, IL-17 could be an inflammatory marker for disease status monitor and a potential therapeutic target.

Case of professor Xu ZOU's acupuncture technique for "benefiting kidney and strengthening anti-pathogenic qi" in promoting the absorption of COVID-19.

A case of the absorption of corona virus disease 2019 (COVID-19) promoted by professor Xu ZOU's acupuncture technique for "benefiting kidney and strengthening anti-pathogenic qi" is introduced. A female patient suffered from COVID-19, 64 years old, had been treated with acupuncture and Chinese herb granules for 10 days on the base of the oral administration of moxifloxacin. In the re-examination, the chest CT image indicated that the absorption of COVID-19 was obvious as compared with before, the nucleic acid test of novel corona virus was negative and the patient narrated no obvious discomfort. Acupuncture therapy plays its active adjuvant effect in the whole process of the treatment of COVID-19.