PurposeRobust biomarkers that predict disease outcomes amongst COVID-19 patients are necessary for both patient triage and resource prioritisation. Numerous candidate biomarkers have been proposed for COVID-19. However, at present, there is no consensus on the best diagnostic approach to predict outcomes in infected patients. Moreover, it is not clear whether such tools would apply to other potentially pandemic pathogens and therefore of use as stockpile for future pandemic preparedness.MethodsWe conducted a multi-cohort observational study to investigate the biology and the prognostic role of interferon alpha-inducible protein 27 (IFI27) in COVID-19 patients.ResultsWe show that IFI27 is expressed in the respiratory tract of COVID-19 patients and elevated IFI27 expression in the lower respiratory tract is associated with the presence of a high viral load. We further demonstrate that the systemic host response, as measured by blood IFI27 expression, is associated with COVID-19 infection. For clinical outcome prediction (e.g., respiratory failure), IFI27 expression displays a high sensitivity (0.95) and specificity (0.83), outperforming other known predictors of COVID-19 outcomes. Furthermore, IFI27 is upregulated in the blood of infected patients in response to other respiratory viruses. For example, in the pandemic H1N1/09 influenza virus infection, IFI27-like genes were highly upregulated in the blood samples of severely infected patients.ConclusionThese data suggest that prognostic biomarkers targeting the family of IFI27 genes could potentially supplement conventional diagnostic tools in future virus pandemics, independent of whether such pandemics are caused by a coronavirus, an influenza virus or another as yet-to-be discovered respiratory virus.

ResumoObjetivo: As células progenitoras endoteliais (CPE), caracterizadas pelo marcador CD133+, contribuem para a neovascularização, e o aumento no número dessas células pode ser uma ferramenta terapêutica promissora. O sangue de cordão umbilical humano contém um número significante de CPE, sugerindo a possibilidade do uso destas células para a revascularização de tecidos isquêmicos. O objetivo desse trabalho foi analisar a funcionalidade das células CD133+ diferenciadas in vitro.Métodos: As células diferenciadas foram caracterizadas 468SENEGAGLIA, AC ET AL -In vitro formation of capillary tubules from human umbilical cord blood cells with perspectives for therapeutic application Bras Cir Cardiovasc 2008; 23(4): 467-473 Rev

Tissue-specific resident cells have been identified as a promising population of progenitor cells for cell-based therapies. We describe here the isolation from adult human hearts of tissue nonspecific alkaline phosphatase-positive cells (ALPL+ cells) with mesenchymal stem cell (MSC) characteristics. Samples from 24 adult cadaveric donors were obtained from a valve bank. Mean total ischemia time was 21.5 ± 9.1 hours. The success rate for the isolation of human heart-derived cells by the explant culture technique was 70% for the right auricle (14 of 20 trials) and 33% for the right ventricle (7 of 21 trials). The total auricle-derived cell population (TAD) was used for the purification of ALPL+ cells. TAD and ALPL+ cells expressed markers for MSC and pericytes. TAD cells and ALPL+ cells differentiated into adipocytes, osteoblasts and chondroblasts, and ALPL+ cells expressed markers of these three lineages more strongly than TAD cells, as shown by RT-PCR. This population therefore has a greater potential for differentiation into mesechymal lineages than TAD cells. Both cell populations express some markers of cardiac progenitors, such as GATA4, CD117 and VEGF. ALPL+ cells expressed troponin T and ABCG2, which are also markers of the cardiac lineage. Heart samples from tissue banks could be considered as sources of MSC with putative commitment towards cardiac lineages, even after prolonged ischemia times

BackgroundRobust biomarkers that predict disease outcomes amongst COVID-19 patients are necessary for both patient triage and resource prioritisation. Numerous candidate biomarkers have been proposed for COVID-19. However, at present, there is no consensus on the best diagnostic approach to predict outcomes in infected patients. Moreover, it is not clear whether such tools would apply to other potentially pandemic pathogens and therefore of use as stockpile for future pandemic preparedness.MethodsWe conducted a multi-cohort observational study to investigate the biology and the prognostic role of interferon alpha-inducible protein 27 (IFI27) in COVID-19 patients.FindingsWe show that IFI27 is expressed in the respiratory tract of COVID-19 patients and elevated IFI27 expression is associated with the presence of a high viral load. We further demonstrate that systemic host response, as measured by blood IFI27 expression, is associated with COVID-19 severity. For clinical outcome prediction (e.g. respiratory failure), IFI27 expression displays a high positive (0.83) and negative (0.95) predictive value, outperforming all other known predictors of COVID-19 severity. Furthermore, IFI27 is upregulated in the blood of infected patients in response to other respiratory viruses. For example, in the pandemic H1N1/09 swine influenza virus infection, IFI27-like genes were highly upregulated in the blood samples of severely infected patients.InterpretationThese data suggest that prognostic biomarkers targeting the family of IFI27 genes could potentially supplement conventional diagnostic tools in future virus pandemics, independent of whether such pandemics are caused by a coronavirus, an influenza virus or another as yet-to-be discovered respiratory virus.Research in contextEvidence before this studyWe searched the scientific literature using PubMed to identify studies that used the IFI27 biomarker to predict outcomes in COVID-19 patients. We used the search terms “IFI27”, “COVID-19, “gene expression” and “outcome prediction”. We did not identify any study that investigated the role of IFI27 biomarker in outcome prediction. Although ten studies were identified using the general terms of “gene expression” and “COVID-19”, IFI27 was only mentioned in passing as one of the identified genes. All these studies addressed the broader question of the host response to COVID-19; none focused solely on using IFI27 to improve the risk stratification of infected patients in a pandemic.Added value of this studyHere, we present the findings of a multi-cohort study of the IFI27 biomarker in COVID-19 patients. Our findings show that the host response, as reflected by blood IFI27 gene expression, accurately predicts COVID-19 disease progression (positive and negative predictive values; 0.83 and 0.95, respectively), outperforming age, comorbidity, C-reactive protein and all other known risk factors. The strong association of IFI27 with disease severity occurs not only in SARS-CoV-2 infection, but also in other respiratory viruses with pandemic potential, such as the influenza virus. These findings suggest that host response biomarkers, such as IFI27, could help identify high-risk COVID-19 patients - those who are more likely to develop infection complications - and therefore may help improve patient triage in a pandemic.Implications of all the available evidenceThis is the first systemic study of the clinical role of IFI27 in the current COVID-19 pandemic and its possible future application in other respiratory virus pandemics. The findings not only could help improve the current management of COVID-19 patients but may also improve future pandemic preparedness.