Intranasal booster using an Omicron vaccine confers broad mucosal and systemic immunity against SARS-CoV-2 variants.

The highly contagious SARS-CoV-2 Omicron subvariants severely attenuated the effectiveness of currently licensed SARS-CoV-2 vaccines based on ancestral strains administered via intramuscular injection. In this study, we generated a recombinant, replication-incompetent human adenovirus type 5, Ad5-S-Omicron, that expresses Omicron BA.1 spike. Intranasal, but not intramuscular vaccination, elicited spike-specific respiratory mucosal IgA and residential T cell immune responses, in addition to systemic neutralizing antibodies and T cell immune responses against most Omicron subvariants. We tested intranasal Ad5-S-Omicron as a heterologous booster in mice that previously received intramuscular injection of inactivated ancestral vaccine. In addition to inducing serum broadly neutralizing antibodies, there was a significant induction of respiratory mucosal IgA and neutralizing activities against Omicron subvariants BA.1, BA.2, BA.5, BA.2.75, BF.7 as well as pre-Omicron strains Wildtype, Beta, and Delta. Serum and mucosal neutralizing activities against recently emerged XBB, BQ.1, and BQ.1.1 could also be detected but were much lower. Nasal lavage fluids from intranasal vaccination contained multimeric IgA that can bind to at least 10 spike proteins, including Omicron subvariants and pre-Omicron strains, and possessed broadly neutralizing activities. Intranasal vaccination using Ad5-S-Omicron or instillation of intranasal vaccinee's nasal lavage fluids in mouse nostrils protected mice against Omicron challenge. Taken together, intranasal Ad5-S-Omicron booster on the basis of ancestral vaccines can establish effective mucosal and systemic immunity against Omicron subvariants and multiple SARS-CoV-2 variants. This candidate vaccine warrants further development as a safe, effective, and user-friendly infection and transmission-blocking vaccine.

Real-world effectiveness of Yindan Jiedu granules-based treatment on patients infected with the SARS-CoV-2 Omicron variants BA.2 combined with high-risk factors: A cohort study.

Background: Our previous studies have shown that Yindan Jiedu granules (YDJDG) can effectively treat coronavirus disease 2019 (COVID-19); however, the high infectivity and the immune escape potential of the Omicron variant BA.2 make it more difficult to control, and patients with high-risk factors prone to progress rapidly. Purpose: To evaluate YDJDG's efficacy in treating patients with the Omicron variant BA.2 with high-risk factors and compared it with that of Paxlovid. Methods: A total of 257 patients who fulfilled the inclusion criteria were allocated to the YDJDG (115 cases), Paxlovid (115 cases), and control (27 cases) groups. A Cox regression model was used to analyze the independent factors affecting the shedding time of nucleic acid in 14 days. Propensity score matching (PSM) was used to match the characteristics of individuals in the three groups, while the Kaplan-Meier method was used to compare the shedding proportion of nucleic acids. Results: Cox analysis showed that the vaccine booster (p = 0.006), YDJDG treatment (p = 0.020), and Paxlovid treatment (p < 0.0001) were independent predictors of nucleic acid shedding at 14 days. The median recovery time was 11.49 days in the YDJDG group, 10.21 days in the Paxlovid group, and 13.93 days in the control group. After PSM (3:1), the results showed that the nucleic acid shedding time of the YDJDG group (n = 53) was 2.47 days shorter than that of the control group (n = 21) (p = 0.0076), while the Paxlovid group (n = 44) had a 4.34 days shorter than that of the control group (n = 17) (p < 0.0001). After PSM (1:1), YDJDG and Paxlovid (76 pairs) were also analyzed. In the YDJDG group, nucleic acid shedding time was 1.43 days longer than that observed in the Paxlovid group (p = 0.020). At 10 and 14 days, the Paxlovid group showed a significant difference in the nucleic acid shedding proportion compared with the control group (p = 0.036, p = 0.0015). A significant difference was also observed between the YDJDG and control groups (p = 0.040) at 14 days. Conclusion: As a safe and convenient oral drug, YDJDG can be used as an alternative to antiviral therapy for such patients.

Measuring Pollution Control and Environmental Sustainable Development in China Based on Parallel DEA Method

The purpose of this study is to explore the impact of pollution control on industrial production efficiency in 31 provinces and cities in the Yellow River and Non-Yellow River basins in China from 2013 to 2017, using the methods of the directional distance function (hereinafter referred to as DDF) and the technology gap ratio (hereinafter referred to as TGR) in parallel, while taking the industrial production sector (labor force, total capital formation, energy consumption and industrial water consumption) and the pollution control sector (wastewater treatment funds and waste gas treatment funds) as input variables. Undesirable outputs (total wastewater discharge, lead, SO2 and smoke and dust in wastewater) and an ideal output variable (industrial output value) are taken as output variables. It is found that the total efficiency of DDF in the Non-Yellow River Basin is 0.9793, which is slightly better than 0.9688 in the Yellow River Basin. Among the 17 provinces and cities with a total efficiency of 1, only Shandong and Sichuan are located in the Yellow River Basin. The TGR values of 31 provinces, cities and administrative regions are less than 1, and the average TGR value of the Yellow River Basin is 0.3825, which is lower than the average TGR value of the Non-Yellow River Basin of 0.5234. We can start by improving the allocation of manpower and capital, implementing the use of pollution prevention and control funds, improving the technical level of industrial production, improving pollutant emission, and increasing output value to improve overall efficiency performance. This study uses the parallel method, taking the industrial production department and the pollution control department as inputs, to objectively evaluate the changes in industrial production efficiency and technology gap in the Yellow River and Non-Yellow River basins, which is conducive to mastering the situation of pollution control and industrial production efficiency, and provides the reference for SDG-6- and SDG-9-related policy making.

Blood purification in sepsis and systemic inflammation.

PURPOSE OF REVIEW: Sepsis and septic shock are life-threatening diseases with high mortality. Although efforts have made to improve the survivals, the outcomes are still frustrating. Blood purification was thought to be a promising adjunctive therapy to regulate the excessive cytokine storm or to reduce the endotoxin activity caused by sepsis. Critically ill COVID-19 characterized with the similar disease to sepsis may also benefit from blood purification. RECENT FINDINGS: The recent studies mainly focused on hemadsorption materials. The results of the clinical trials showed a tendency in decrease of cytokine levels and endotoxin activity and improvement in haemodynamics. However, the results were controversial. More evidence about blood purification in sepsis and COVID-19 are needed from currently ongoing trials and future well designed trials. SUMMARY: The blood purification therapy demonstrated the tendency in decrease of cytokines and endotoxin activity in different degree according to the current studies. However, the effect on mortality and haemodynamics is still in controversy. Further well designed, large sample sized studies should focus on the timing of initiating blood purification, the appropriate indications and the optimal type of blood purification membrane or cartridge to provide more evidence for clinical practice.

Conversational Task Increases Heart Rate Variability of Individuals Susceptible to Perceived Social Isolation.

Studies showed that introversion is the strongest personality trait related to perceived social isolation (loneliness), which can predict various complications beyond objective isolation such as living alone. Lonely individuals are more likely to resort to social media for instantaneous comfort, but it is not a perpetual solution. Largely negative implications including poorer interpersonal relationship and depression were reported due to excessive social media usage. Conversational task is an established intervention to improve verbal communication, cognitive and behavioral adaptation among lonely individuals. Despite that behavioral benefits have been reported, it is unclear if they are accompanied by objective benefits underlying physiological changes. Here, we investigate the physiological signals from 28 healthy individuals during a conversational task. Participants were ranked by trait extraversion, where greater introversion is associated with increased susceptibility to perceived social isolation as compared to participants with greater extraversion as controls. We found that introverts had a greater tendency to be neurotic, and these participants also exhibited significant differences in task-related electrodermal activity (EDA), heart rate (HR) and HR variability (HRV) as compared to controls. Notably, resting state HRV among individuals susceptible to perceived loneliness was below the healthy thresholds established in literature. Conversational task with a stranger significantly increased HRV among individuals susceptible to isolation up to levels as seen in controls. Since HRV is also elevated by physical exercise and administration of oxytocin hormone (one form of therapy for behavioral isolation), conversational therapy among introverts could potentially confer physiological benefits to ameliorate social isolation and loneliness. Our findings also suggest that although the recent pandemic has changed how people are interacting typically, we should maintain a healthy dose of social interaction innovatively.

Analysis of B Cell Receptor Repertoires Reveals Key Signatures of the Systemic B Cell Response after SARS-CoV-2 Infection.

A comprehensive study of the B cell response against SARS-CoV-2 could be significant for understanding the immune response and developing therapeutical antibodies and vaccines. To define the dynamics and characteristics of the antibody repertoire following SARS-CoV-2 infection, we analyzed the mRNA transcripts of immunoglobulin heavy chain (IgH) repertoires of 24 peripheral blood samples collected between 3 and 111 days after symptom onset from 10 COVID-19 patients. Massive clonal expansion of naive B cells with limited somatic hypermutation (SHM) was observed in the second week after symptom onset. The proportion of low-SHM IgG clones strongly correlated with spike-specific IgG antibody titers, highlighting the significant activation of naive B cells in response to a novel virus infection. The antibody isotype switching landscape showed a transient IgA surge in the first week after symptom onset, followed by a sustained IgG elevation that lasted for at least 3 months. SARS-CoV-2 infection elicited poly-germ line reactive antibody responses. Interestingly, 17 different IGHV germ line genes recombined with IGHJ6 showed significant clonal expansion. By comparing the IgH repertoires that we sequenced with the 774 reported SARS-CoV-2-reactive monoclonal antibodies (MAbs), 13 shared spike-specific IgH clusters were found. These shared spike-specific IgH clusters are derived from the same lineage of several recently published neutralizing MAbs, including CC12.1, CC12.3, C102, REGN10977, and 4A8. Furthermore, identical spike-specific IgH sequences were found in different COVID-19 patients, suggesting a highly convergent antibody response to SARS-CoV-2. Our analysis based on sequencing antibody repertoires from different individuals revealed key signatures of the systemic B cell response induced by SARS-CoV-2 infection. IMPORTANCE Although the canonical delineation of serum antibody responses following SARS-CoV-2 infection has been well established, the dynamics of antibody repertoire at the mRNA transcriptional level has not been well understood, especially the correlation between serum antibody titers and the antibody mRNA transcripts. In this study, we analyzed the IgH transcripts and characterized the B cell clonal expansion and differentiation, isotype switching, and somatic hypermutation in COVID-19 patients. This study provided insights at the repertoire level for the B cell response after SARS-CoV-2 infection.

Yindan Jiedu granules exhibit anti-inflammatory effect in patients with novel Coronavirus disease (COVID-19) by suppressing the NF-κB signaling pathway.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a pandemic that has caused a high number of deaths worldwide. Inflammatory factors may play important roles in COVID-19 progression. Yindan Jiedu granules (YDJDG) can inhibit the progression of COVID-19, but the associated mechanism is unclear. PURPOSE: To evaluate the therapeutic effects of YDJDG on COVID-19 and explore its underlying mechanism. METHODS: We recruited 262 participants and randomly assigned 97 patients each to the YDJDG and control groups using one-to-one propensity score matching (PSM). Clinical effects were observed and serum inflammatory and immune indicators were measured. The target network model of YDJDG was established by predicting and determining the targets of identified compounds. The main constituents of the YDJDG extracts were identified and evaluated using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and molecular docking. Besides, the anti-inflammatory effects of YDJDG and its specific biological mechanism of action were studied. RESULTS: After PSM, the results showed that compared with the control group, the YDJDG group had a shorter time of dissipation of acute pulmonary exudative lesions (p < 0.0001), shorter time to negative conversion of viral nucleic acid (p < 0.01), more rapid decrease in serum amyloid A level and erythrocyte sedimentation rate (p < 0.0001), and a higher rate of increase in CD4+T cell count (p = 0.0155). By overlapping the genes of YDJDG and COVID-19, 213 co-targeted genes were identified. Metascape enrichment analysis showed that 25 genes were significantly enriched in the NF-κB pathway, which were mainly targets of luteolin, quercetin, and kaempferol as confirmed by MS analysis. Molecular docking revealed that the ligands of three compounds had strong interaction with NF-κB p65 and IκBα. In vivo, YDJDG significantly protected animals from lipopolysaccharide (LPS)-induced acute lung injury (ALI), decreasing the lung wet/dry weight ratio, ALI score, and lung histological damage. In LPS-treated RAW264.7 cells, YDJDG suppressed nuclear translocation of NF-κB p65. In vivo and in vitro, YDJDG exerted anti-inflammatory effects by inhibiting the production of inflammatory cytokines (IL-6, IL-1ß, and TNF-α). These effects were accompanied by the inhibition of NF-ĸB activation and IκBα phosphorylation. CONCLUSION: YDJDG may shorten the COVID-19 course and delay its progression by suppressing inflammation via targeting the NF-κB pathway.

Application of QR code in three-level pre-viewing triage system in a hospital's responding Beijing Xinfadi wholesale market COVID-19 epidemic

OBJECTIVE: To explore the scientific value of the three-level pre-viewing triage management practice by using "Alipay" health code and self-developed electronic version of screening table QR code to assist COVID-19 screening in a general hospital. METHODS: During Beijing Xinfadi wholesale market COVID-19 epidemic, the definition of epidemiological history and clinical symptom case of pre-viewing and triage were determined by referring to the COVID-19 Diagnosis and Treatment Protocol(Trial Seventh Edition). Through strengthening hospital import and export management, setting up the pre-viewing triage points scientifically, improving the three-level pre-viewing triage process by using information technology to improve efficiency, the three-level pre-viewing triage system was strictly implement. Data included information released by the country and the region, daily reports on the workload of the hospital. RESULTS: During the epidemic period in Beijing(June 11-July 5), the number of online appointments and the number of general outpatient clinics showed a downward trend compared with before and after period, and the difference was significant(P<0.05). The number of fever outpatient during the epidemic period in Xinfadi wholesale market accounted for 2.1%(6 647/322 041) of the total number of visits during the epidemic period, which was positively correlated with the number of confirmed cases in Xinfadi wholesale market(r_s=0.755). During the same period, the hospital confirmed 2 cases of coronal virus disease and 3 cases of asymptomatic infection;25 cases with positive epidemiological history and 920 cases with fever were detected, and all of them were guided to the fever clinic in an orderly manner. All medical staff and patients had zero infection. CONCLUSION: The three-level pre-viewing triage system is conductive to reduce the risk of nosocomial infection. The application of "QR code" is of great significance to improve the efficiency of pre-viewing triage and to achieve precise prevention and control of epidemics.

Cathepsin L plays a key role in SARS-CoV-2 infection in humans and humanized mice and is a promising target for new drug development.

To discover new drugs to combat COVID-19, an understanding of the molecular basis of SARS-CoV-2 infection is urgently needed. Here, for the first time, we report the crucial role of cathepsin L (CTSL) in patients with COVID-19. The circulating level of CTSL was elevated after SARS-CoV-2 infection and was positively correlated with disease course and severity. Correspondingly, SARS-CoV-2 pseudovirus infection increased CTSL expression in human cells in vitro and human ACE2 transgenic mice in vivo, while CTSL overexpression, in turn, enhanced pseudovirus infection in human cells. CTSL functionally cleaved the SARS-CoV-2 spike protein and enhanced virus entry, as evidenced by CTSL overexpression and knockdown in vitro and application of CTSL inhibitor drugs in vivo. Furthermore, amantadine, a licensed anti-influenza drug, significantly inhibited CTSL activity after SARS-CoV-2 pseudovirus infection and prevented infection both in vitro and in vivo. Therefore, CTSL is a promising target for new anti-COVID-19 drug development.

Multifaceted Optimization of MSC-Based Formulation upon Sodium Iodoacetate-Induced Osteoarthritis Models by Combining Advantageous HA/PG Hydrogel and Fluorescent Tracer

Owing to the boundedness of conventional remedies upon articular cartilage for self-rehabilitation and the incrementally senior citizens, the incidence of osteoarthritis (OA) is increasing worldwide. Empirical studies have revealed the advantageous and promising potentials of mesenchymal stem/stromal cells (MSCs) on the refractory OA, whereas the deficiency of systematic and detailed exploration of MSC-based therapy largely hampers the large-scale applications in regenerative medicine. Herein, we initially utilized the monosodium iodoacetate- (MIA-) induced OA rabbit models and investigated the therapeutic effect of human umbilical cord-derived UC-MSCs at serial dose gradients with the splendid hyaluronic acid and/or propylene glycol hydrogels (HA, HA/PG), respectively. Afterwards, we turned to a dual-luciferase reporter tracing system and evaluated the spatiotemporal distribution and metabolokinetics of bifluorescence expressing UC-MSCs (BF-MSCs) in OA rats. Of the aforementioned trials, we verified that the combination of HA/PG and middle-dose MSCs (0.5×107 cells/ml) eventually manifested the optimal efficacy on OA rabbits. Furthermore, with the aid of the bioluminescence imaging (BLI) technology for dynamic in vitro and in vivo tracking, we intuitively delineated the spatiotemporal distribution and therapeutic process of BF-MSCs in OA rats, which substantially confirmed the reinforcement of HA/PG on BF-MSCs for OA treatment. Collectively, our data conformably demonstrated that the middle dose of UC-MSCs combined with HA/PG hydrogel was sufficient for optimal MSC-based formulation for blocking OA progression and promoting cartilage repair, which supplied overwhelming new references and enlightened MSC-based therapeutic strategies for cartilage defects.

Early Use of Corticosteroid May Prolong SARS-CoV-2 Shedding in Non-Intensive Care Unit Patients with COVID-19 Pneumonia: A Multicenter, Single-Blind, Randomized Control Trial.

BACKGROUND: There is still no clinical evidence available to support or to oppose corticosteroid treatment for coronavirus disease 2019 (COVID-19) pneumonia. OBJECTIVE: To investigate the efficacy and safety of corticosteroid given to the hospitalized patients with COVID-19 pneumonia. METHODS: This was a prospective, multicenter, single-blind, randomized control trial. Adult patients with COVID-19 pneumonia who were admitted to the general ward were randomly assigned to either receive methylprednisolone or not for 7 days. The primary end point was the incidence of clinical deterioration 14 days after randomization. RESULTS: We terminated this trial early because the number of patients with COVID-19 pneumonia in all the centers decreased in late March. Finally, a total of 86 COVID-19 patients underwent randomization. There was no difference of the incidence of clinical deterioration between the methylprednisolone group and control group (4.8 vs. 4.8%, p = 1.000). The duration of throat viral RNA detectability in the methylprednisolone group was 11 days (interquartile range, 6-16 days), which was significantly longer than that in the control group (8 days [2-12 days], p = 0.030). There were no significant differences between the 2 groups in other secondary outcomes. Mass cytometry discovered CD3+ T cells, CD8+ T cells, and NK cells in the methylprednisolone group which were significantly lower than those in the control group after randomization (p < 0.05). CONCLUSIONS: From this prematurely closed trial, we found that the short-term early use of corticosteroid could suppress the immune cells, which may prolong severe acute respiratory syndrome coronavirus 2 shedding in patients with COVID-19 pneumonia. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04273321.

Corrigendum: Longitudinal Analysis of T and B Cell Receptor Repertoire Transcripts Reveal Dynamic Immune Response in COVID-19 Patients.

[This corrects the article .].

Safety and feasibility of umbilical cord mesenchymal stem cells in patients with COVID-19 pneumonia: A pilot study.

OBJECTIVES: We aim to explore the safety and feasibility of umbilical cord mesenchymal stem cells (UC-MSCs) transplantation in patients with severe and critically severe coronavirus disease-2019 (COVID-19). METHODS: We conducted a small sample, single arm, pilot trial. In addition to standard therapy, we performed four rounds of transplantation of UC-MSCs in sixteen patients with severe and critically severe COVID-19. We recorded adverse events from enrolment to Day 28. We evaluated the oxygenation index, inflammatory biomarkers, radiological presentations of the disease and lymphocyte subsets count on the 7th day (D7 ± 1 day), the 14th day (D14 ± 1 day) and the 28th day (D28 ± 3 days). RESULTS: There were no infusion-related or allergic reactions. The oxygenation index was improved after transplantation. The mortality of enrolled patients was 6.25%, whereas the historical mortality rate was 45.4%. The level of cytokines estimated varied in the normal range, the radiological presentations (ground glass opacity) were improved and the lymphocyte count and lymphocyte subsets (CD4+ T cells, CD8+ T cells and NK cells) count showed recovery after transplantation. CONCLUSIONS: Intravenous transplantation of UC-MSCs was safe and feasible for treatment of patients with severe and critically severe COVID-19 pneumonia.

Clinical characteristics and outcomes of discharged COVID-19 patients with reoccurrence of SARS-CoV-2 RNA.

AIM: Data are limited on clinical characteristics and outcomes of recovered the 2019 coronavirus disease (COVID-19) patients with the reoccurrence of SARS-CoV-2 RNA. PATIENTS & METHODS: Discharged patients in our hospital were included, who had recovered from COVID-19 with the reoccurrence of SARS-CoV-2 RNA. RESULTS: Six patients were redetectable and positive for SARS-CoV-2 RNA after discharge from 3 to 15 days. The main symptoms, although no fever, included fatigue, dry cough and pharyngeal or chest discomfort, which were generally milder in the repositive period compared with the period of initial infection. Their laboratory indexes were significantly improved compared with the initial infection, and the pulmonary lesions were continuously improving. All close contacts were SARS-CoV-2 RNA-negative. CONCLUSION: No worsening outcomes or active transmission to close contacts were found for the repositive COVID-19 patients.

Longitudinal Analysis of T and B Cell Receptor Repertoire Transcripts Reveal Dynamic Immune Response in COVID-19 Patients.

Severe COVID-19 is associated with profound lymphopenia and an elevated neutrophil to lymphocyte ratio. We applied a novel dimer avoidance multiplexed polymerase chain reaction next-generation sequencing assay to analyze T (TCR) and B cell receptor (BCR) repertoires. Surprisingly, TCR repertoires were markedly diminished during the early onset of severe disease but recovered during the convalescent stage. Monitoring TCR repertoires could serve as an indicative biomarker to predict disease progression and recovery. Panoramic concurrent assessment of BCR repertoires demonstrated isotype switching and a transient but dramatic early IgA expansion. Dominant B cell clonal expansion with decreased diversity occurred following recovery from infection. Profound changes in T cell homeostasis raise critical questions about the early events in COVID-19 infection and demonstrate that immune repertoire analysis is a promising method for evaluating emergent host immunity to SARS-CoV-2 viral infection, with great implications for assessing vaccination and other immunological therapies.

Lower Circulating Interferon-Gamma Is a Risk Factor for Lung Fibrosis in COVID-19 Patients.

Cytokine storm resulting from SARS-CoV-2 infection is one of the leading causes of acute respiratory distress syndrome (ARDS) and lung fibrosis. We investigated the effect of inflammatory molecules to identify any marker that is related to lung fibrosis in coronavirus disease 2019 (COVID-19). Seventy-six COVID-19 patients who were admitted to Youan Hospital between January 21 and March 20, 2020 and recovered were recruited for this study. Pulmonary fibrosis, represented as fibrotic volume on chest CT images, was computed by an artificial intelligence (AI)-assisted program. Plasma samples were collected from the participants shortly after admission, to measure the basal inflammatory molecules levels. At discharge, fibrosis was present in 46 (60.5%) patients whose plasma interferon-γ (IFN-γ) levels were twofold lower than those without fibrosis (p > 0.05). The multivariate-adjusted logistic regression analysis demonstrated the inverse association risk of having lung fibrosis and basal circulating IFN-γ levels with an estimate of 0.43 (p = 0.02). Per the 1-SD increase of basal IFN-γ level in circulation, the fibrosis volume decreased by 0.070% (p = 0.04) at the discharge of participants. The basal circulating IFN-γ levels were comparable with c-reactive protein in the discrimination of the occurrence of lung fibrosis among COVID-19 patients at discharge, unlike circulating IL-6 levels. In conclusion, these data indicate that decreased circulating IFN-γ is a risk factor of lung fibrosis in COVID-19.

An adenovirus-vectored COVID-19 vaccine confers protection from SARS-COV-2 challenge in rhesus macaques.

The rapid spread of coronavirus SARS-CoV-2 greatly threatens global public health but no prophylactic vaccine is available. Here, we report the generation of a replication-incompetent recombinant serotype 5 adenovirus, Ad5-S-nb2, carrying a codon-optimized gene encoding Spike protein (S). In mice and rhesus macaques, intramuscular injection with Ad5-S-nb2 elicits systemic S-specific antibody and cell-mediated immune (CMI) responses. Intranasal inoculation elicits both systemic and pulmonary antibody responses but weaker CMI response. At 30 days after a single vaccination with Ad5-S-nb2 either intramuscularly or intranasally, macaques are protected against SARS-CoV-2 challenge. A subsequent challenge reveals that macaques vaccinated with a 10-fold lower vaccine dosage (1 × 1010 viral particles) are also protected, demonstrating the effectiveness of Ad5-S-nb2 and the possibility of offering more vaccine dosages within a shorter timeframe. Thus, Ad5-S-nb2 is a promising candidate vaccine and warrants further clinical evaluation.

Kinetics of SARS-CoV-2 specific IgM and IgG responses in COVID-19 patients.

The emerging COVID-19 caused by SARS-CoV-2 infection poses severe challenges to global public health. Serum antibody testing is becoming one of the critical methods for the diagnosis of COVID-19 patients. We investigated IgM and IgG responses against SARS-CoV-2 nucleocapsid (N) and spike (S) protein after symptom onset in the intensive care unit (ICU) and non-ICU patients. 130 blood samples from 38 COVID-19 patients were collected. The levels of IgM and IgG specific to N and S protein were detected by ELISA. A series of blood samples were collected along the disease course from the same patient, including 11 ICU patients and 27 non-ICU patients for longitudinal analysis. N and S specific IgM and IgG (N-IgM, N-IgG, S-IgM, S-IgG) in non-ICU patients increased after symptom onset. N-IgM and S-IgM in some non-ICU patients reached a peak in the second week, while N-IgG and S-IgG continued to increase in the third week. The combined detection of N and S specific IgM and IgG could identify up to 75% of SARS-CoV-2 infected patients in the first week. S-IgG was significantly higher in non-ICU patients than in ICU patients in the third week. In contrast, N-IgG was significantly higher in ICU patients than in non-ICU patients. The increase of S-IgG positively correlated with the decrease of C-reactive protein (CRP) in non-ICU patients. N and S specific IgM and IgG increased gradually after symptom onset and can be used for detection of SARS-CoV-2 infection. Analysis of the dynamics of S-IgG may help to predict prognosis.