Yunwen Hu

Bio: Yunwen Hu is an academic researcher from Fudan University. The author has contributed to research in topics: Virus & Influenza A virus. The author has an hindex of 29, co-authored 85 publications receiving 4575 citations. Previous affiliations of Yunwen Hu include Fudan University Shanghai Medical College.

Human Infection with a Novel Avian-Origin Influenza A (H7N9) Virus

Abstract: Background Infection of poultry with influenza A subtype H7 viruses occurs worldwide, but the introduction of this subtype to humans in Asia has not been observed previously. In March 2013, three urban residents of Shanghai or Anhui, China, presented with rapidly progressing lower respiratory tract infections and were found to be infected with a novel reassortant avian-origin influenza A (H7N9) virus. Methods We obtained and analyzed clinical, epidemiologic, and virologic data from these patients. Respiratory specimens were tested for influenza and other respiratory viruses by means of real-time reverse-transcriptase–polymerase-chain-reaction assays, viral culturing, and sequence analyses. Results A novel reassortant avian-origin influenza A (H7N9) virus was isolated from respiratory specimens obtained from all three patients and was identified as H7N9. Sequencing analyses revealed that all the genes from these three viruses were of avian origin, with six internal genes from avian influenza A (H9N2) virus...

Recovery from severe H7N9 disease is associated with diverse response mechanisms dominated by CD8⁺ T cells.

Abstract: The avian origin A/H7N9 influenza virus causes high admission rates (>99%) and mortality (>30%), with ultimately favourable outcomes ranging from rapid recovery to prolonged hospitalization. Using a multicolour assay for monitoring adaptive and innate immunity, here we dissect the kinetic emergence of different effector mechanisms across the spectrum of H7N9 disease and recovery. We find that a diversity of response mechanisms contribute to resolution and survival. Patients discharged within 2-3 weeks have early prominent H7N9-specific CD8(+) T-cell responses, while individuals with prolonged hospital stays have late recruitment of CD8(+)/CD4(+) T cells and antibodies simultaneously (recovery by week 4), augmented even later by prominent NK cell responses (recovery >30 days). In contrast, those who succumbed have minimal influenza-specific immunity and little evidence of T-cell activation. Our study illustrates the importance of robust CD8(+) T-cell memory for protection against severe influenza disease caused by newly emerging influenza A viruses.

Correction: Corrigendum: The Serum Profile of Hypercytokinemia Factors Identified in H7N9-Infected Patients can Predict Fatal Outcomes

Abstract: Scientific Reports 5: Article number: 10942; published online: 01 June 2015; updated: 23 February 2016 This Article contains typographical errors in Table 2 where ‘Week 2 (N = 32)’ was incorrectly given as ‘Week (N = 2)’.

GISAID: Global initiative on sharing all influenza data - from vision to reality.

Abstract: Yuelong Shu1, John McCauley2 1. WHO Collaborating Center for Reference and Research on Influenza, Chinese National Influenza Center, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China 2. WHO Collaborating Centre for Reference and Research on Influenza, Crick Worldwide Influenza Centre, the Francis Crick Institute, London, United Kingdom

Characteristics of pediatric SARS-CoV-2 infection and potential evidence for persistent fecal viral shedding.

Abstract: We report epidemiological and clinical investigations on ten pediatric SARS-CoV-2 infection cases confirmed by real-time reverse transcription PCR assay of SARS-CoV-2 RNA. Symptoms in these cases were nonspecific and no children required respiratory support or intensive care. Chest X-rays lacked definite signs of pneumonia, a defining feature of the infection in adult cases. Notably, eight children persistently tested positive on rectal swabs even after nasopharyngeal testing was negative, raising the possibility of fecal-oral transmission.

Association of the adam33 gene with asthma and bronchial hyperresponsiveness

Abstract: Van Eerdewegh P, Little RD, Dupuis J, et al Nature 2002;418:426–430 To identify novel genetic polymorphisms associated with bronchial hyperresponsiveness (BHR) in asthma Four hundred sixty white affected sib-pair families from the United States and the United Kingdom with current asthma A genetic linkage analysis was performed for current asthma and BHR Case-control, transmission disequilibrium, and haplotype analyses were conducted to identify the gene(s) most commonly associated with asthma Novel genes of interest were …

Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19.

Abstract: To the Editor — We report the kinetics of immune responses in relation to clinical and virological features of a patient with mild-to-moderate coronavirus disease 2019 (COVID-19) that required hospitalization. Increased antibody-secreting cells (ASCs), follicular helper T cells (TFH cells), activated CD4+ T cells and CD8+ T cells and immunoglobulin M (IgM) and IgG antibodies that bound the COVID-19causing coronavirus SARS-CoV-2 were detected in blood before symptomatic recovery. These immunological changes persisted for at least 7 d following full resolution of symptoms. A 47-year-old woman from Wuhan, Hubei province, China, presented to an emergency department in Melbourne, Australia. Her symptoms commenced 4 d earlier with lethargy, sore throat, dry cough, pleuritic chest pain, mild dyspnea and subjective fevers (Fig. 1a). She traveled from Wuhan to Australia 11 d before presentation. She had no contact with the Huanan seafood market or with known COVID-19 cases. She was otherwise healthy and was a non-smoker taking no medications. Clinical examination revealed a temperature of 38.5 °C, a pulse rate of 120 beats per minute, a blood pressure of 140/80 mm Hg, a respiratory rate of 22 breaths per minute, and oxygen saturation 98% while breathing ambient air. Lung auscultation revealed bi-basal rhonchi. At presentation on day 4, SARS-CoV-2 was detected in a nasopharyngeal swab specimen by real-time reverse-transcriptase PCR. SARS-CoV-2 was again detected at days 5–6 in nasopharyngeal, sputum and fecal samples, but was undetectable from day 7 (Fig. 1a). Blood C-reactive protein was elevated at 83.2, with normal counts of lymphocytes (4.3 × 109 cells per liter (range, 4.0 × 109 to 12.0 × 109 cells per liter)) and neutrophils (6.3 × 109 cells per liter (range, 2.0 × 109 to 8.0 × 109 × 109 cells per liter)). No other respiratory pathogens were detected. Her management was intravenous fluid rehydration without supplemental oxygenation. No antibiotics, steroids or antiviral agents were administered. Chest radiography demonstrated bi-basal infiltrates at day 5 that cleared on day 10 (Fig. 1b). She was discharged to home isolation on day 11. Her symptoms resolved completely by day 13, and she remained well at day 20, with progressive increases in plasma SARS-CoV-2-binding IgM and IgG antibodies from day 7 until day 20 (Fig. 1c and Extended Data Fig. 1). The patient was enrolled through the Sentinel Travelers Research Preparedness Platform for Emerging Infectious Diseases novel coronavirus substudy (SETREP-ID-coV) and provided written informed consent before the study. Patient care and research were conducted in compliance with the Case Report guidelines and the Declaration of Helsinki. Experiments were performed with ethics approvals HREC/17/MH/53, HREC/15/MonH/64/2016.196 and UoM#1442952.1/#1443389.4. We analyzed the kinetics and breadth of immune responses associated with clinical resolution of COVID-19. As ASCs are key for the rapid production of antibodies following infection with Ebola virus1,2 and infection with and vaccination against influenza virus2,3, and activated circulating TFH cells (cTFH cells) are concomitantly induced following vaccination against influenza virus3, we defined the frequency of CD3–CD19+CD27hiCD38hi ASC and CD4+CXCR5+ICOS+PD-1+ cTFH cell responses before symptomatic recovery. ASCs appeared in the blood at the time of viral clearance (day 7; 1.48%) and peaked on day 8 (6.91%). The emergence of cTFH cells occurred concurrently in blood at day 7 (1.98%), increasing on day 8 (3.25%) and day 9 (4.46%) (Fig. 1d). The peak of both ASCs and cTFH cells was markedly higher in the patient with COVID-19 than in healthy control participants (0.61% ± 0.40% and 1.83% ± 0.77%, respectively (average ± s.d.); n = 5). Both ASCs and cTFH cells were prominently present during convalescence (day 20) (4.54% and 7.14%, respectively; Fig. 1d). Thus, our study provides evidence on the recruitment of both ASCs and cTFH cells in this patient’s blood while she was still unwell and 3 d before the resolution of symptoms. Since co-expression of CD38 and HLA-DR is the key phenotype of the activation of CD8+ T cells in response to viral infections, we analyzed co-expression of CD38 and HLA-DR. As per reports for Ebola and influenza1,4, co-expression of CD38 and HLA-DR on CD8+ T cells (assessed as the frequency of CD38+HLA-DR+ CD8+ T cells) rapidly increased in this patient from day 7 (3.57%) to day 8 (5.32%) and day 9 (11.8%), then decreased at day 20 (7.05%) (Fig. 1e). Furthermore, the frequency of CD38+HLA-DR+ CD8+ T cells was much higher in this patient than in healthy individuals (1.47% ± 0.50%; n = 5). CD38+HLA-DR+ T cells were also recently documented in a patient with COVID-19 at one time point5. Similarly, co-expression of CD38 and HLA-DR on CD4+ T cells (assessed as the frequency of CD38+HLA-DR+ CD4+ T cells) increased between day 7 (0.55%) and day 9 (3.33%) in this patient, relative to that of healthy donors (0.63% ± 0.28%; n = 5), although at lower levels than that of CD8+ T cells. CD38+HLA-DR+ T cells, especially CD8+ T cells, produced larger amounts of granzymes A and B and perforin (~34–54% higher) than did their parent cells (CD8+ or CD4+ populations; Fig. 1e). Thus, the emergence and rapid increase in activated CD38+HLA-DR+ T cells, especially CD8+ T cells, at days 7–9 preceded the resolution of symptoms. Details on data reproducibility are in the Life Sciences Reporting Summary. Analysis of CD16+CD14+ monocytes, which are related to immunopathology, showed lower frequencies of CD16+CD14+ monocytes in the blood of this patient at days 7, 8 and 9 (1.29%, 0.43% and 1.47%, respectively) than in that of healthy control donors (9.03% ± 4.39%; n = 5) (Fig. 1f), possibly indicative of the efflux of CD16+CD14+ monocytes from the blood to the site of infection. No differences in activated HLA-DR+CD3–CD56+ natural killer cells were found. As pro-inflammatory cytokines and chemokines are predictive of severe clinical outcomes for influenza6, we quantified 17 pro-inflammatory cytokines and chemokines in plasma. We found low levels of the chemokine MCP-1 (CCL2) in the patient’s plasma (Extended Data Fig. 2a), although this was comparable to results obtained for healthy donors (22.15 ± 13.81; n = 5), patients infected with influenza A virus or influenza B, assessed at days 7–9