Immunoinformatic analysis of the SARS-CoV-2 envelope protein as a strategy to assess cross-protection against COVID-19

Envelope protein of coronaviruses is a structural protein existing in both monomeric and homo-pentameric form. It has been related to a multitude of roles including virus infection, replication, dissemination and immune response stimulation. In the present study, we employed an immunoinformatic approach to investigate the major immunogenic domains of the SARS-CoV-2 envelope protein and map them among the homologue proteins of coronaviruses with tropism for animal species that are closely inter-related with the human beings population all over the world. Also, when not available, we predicted the envelope protein structural folding and mapped SARS-CoV-2 epitopes. Envelope sequences alignment provides evidence of high sequence homology for some of the investigated virus specimens; while the structural mapping of epitopes resulted in the interesting maintenance of the structural folding and epitope sequence localization also in the envelope proteins scoring a lower alignment score. In line with the One-Health approach, our evidences provide a molecular structural rationale for a potential role of taxonomically related coronaviruses in conferring protection from SARS-CoV-2 infection and identifying potential candidates for the development of diagnostic tools and prophylactic-oriented strategies.     

Sustainability of SARS-CoV-2 Induced Humoral Immune Responses in COVID-19 Patients from Hospitalization to Convalescence Over Six Months

Virologica Sinica - Understanding the persistence of antibody in convalescent COVID-19 patients may help to answer the current major concerns such as the risk of reinfection, the protection period...     

COVID-19确诊病例居住环境病毒检测结果分析及防控探讨

新型冠状病毒肺炎(COVID-19)传播速度快、感染范围广,其感染方式主要是聚集性感染,感染途径主要是呼吸道飞沫和接触传播。了解环境中,特别是COVID-19确诊病人生活环境中的病毒存在情况,是做好环境消毒,阻断新型冠状病毒(SARS-CoV-2)传播的重要步骤,对COVID-19防控具有重要意义。本研究旨在探讨COVID-19患者生活环境中SARS-CoV-2的存在情况,从SARS-CoV-2存在的空间部位、病毒核酸含量、消毒效果等方面对SARS-CoV-2的相关特点做出初步研究,为制定有效的SARS-CoV-2防控措施提供科学依据。本研究以COVID-19病例治疗前的3个家庭居住环境和治疗出院后隔离期间的2个宾馆居住环境中采集的样本为研究材料,采用RT-PCR方法检测样本中的SARS-CoV-2核酸并进行比较分析。结果显示,首次从3个家庭环境中采样48份,RTPCR检测SARS-CoV-2核酸阳性5份(10.42%),3个家庭的环境样本中均有阳性样本检出。首次采样48h后在家庭3进行第二次采样16份,SARS-CoV-2核酸检测阳性2份(12.5%),检测Ct值比首次升高。家庭3消毒后24h采集的16份样本SARS-CoV-2核酸检测均为阴性,并且两处宾馆环境采集的24份样本SARS-CoV-2核酸检测也均为阴性。本研究提示,COVID-19病例的生活环境中可以检出SARS-CoV-2,病毒存在区域、存在物品、病毒核酸含量均有差异;对外环境进行消毒可以达到消毒目的,能够起到阻断SARS-CoV-2传播的防控效果。     

Digging the rabbit hole,COVID-19 edition: anti-vaccine themes and the discourse around COVID-19

This article draws on a broadcast popular among the anti-vaccine community to map out six themes used by the broadcast to mislead viewers about COVID-19. The themes are the claim that “they” – government and pharma – are lying to you, claims that COVID-19 is an excuse to remove civil liberties, viewing everyone as an expert, claiming that science cannot save us, skewing the science, and a claim that “they” are out to harm the viewers. The article points out that similar themes are used to mislead followers with anti-vaccine information. It highlights the concern that these themes will not only mislead people who are already anti-vaccine about the pandemic, but may draw in people who are not anti-vaccine but are seeking information about COVID-19, and suggests some options for dealing with the misinformation. Scientists benefit from understanding these claims, as we are often tasked with providing rebuttals to this misinformation.     

Dynamic Changes of Antibodies to SARS-CoV-2 in COVID-19 Patients at Early Stage of Outbreak

Virologica Sinica - The coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has spread around the world with high mortality. To diagnose promptly and accurately is the vital step to...     

Linear epitope landscape of the SARS-CoV-2 Spike protein constructed from 1,051 COVID-19 patients

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Sex differences in immune responses to SARS-CoV-2 in patients with COVID-19

Millions of people infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been diagnosed with coronavirus infectious disease 2019 (COVID-19). The prevalence and severity of COVID-19 differ between sexes. To explain these differences, we analyzed clinical features and laboratory values in male and female COVID-19 patients. The present study included a cohort of 111 people, i.e. 36 COVID-19 patients, 54 sex- and age-matched common viral community-acquired pneumonia (CAP) patients, and 21 healthy controls. Monocyte counts, lymphocyte subset counts, and alanine aminotransferase (ALT), aspartate aminotransferase (AST), and C-reactive protein (CRP) levels in the peripheral blood were analyzed. Higher Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, monocyte counts, and CRP and ALT levels were found in male COVID-19 patients. Decreased lymphocyte subset counts and proportions were observed in COVID-19 patients, except for the CD3⁺ and CD8⁺ T cell proportions. The lower CD4⁺ T cell proportions and higher CD8⁺ T cell proportions were observed in male and severe COVID-19 patients and the differences were independent of estrogen level. The CD4⁺ T cell proportion was negatively associated with the CD8⁺ T cell proportion in male COVID-19 patients; this correlation was non-significant in females. Our work demonstrates differences between sexes in circulating monocyte counts and CD4⁺ T cell and CD8⁺ T cell proportions in COVID-19 patients, independent of estrogen levels, are associated with the clinical manifestations in COVID-19 patients with high specificity.     

Probable Pangolin Origin of SARS-CoV-2 Associated with the COVID-19 Outbreak

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COVID-19 and Fungal infections: a double debacle

Fungal infections remain hardly treatable because of unstandardized diagnostic tests, limited antifungal armamentarium, and more specifically, potential toxic interactions between antifungals and immunosuppressants used during anti-inflammatory therapies, such as those set up in critically ill COVID-19 patients. Taking into account pre-existing difficulties in treating vulnerable COVID-19 patients, any co-occurrence of infectious diseases like fungal infections constitutes a double debacle for patients, healthcare experts, and the public economy. Since the first appearance of SARS-CoV-2, a significant rise in threatening fungal co-infections in COVID-19 patients has been testified in the scientific literature. Better management of fungal infections in COVID-19 patients is, therefore, a priority and requires highlighting common risk factors, relationships with immunosuppression, as well as challenges in fungal diagnosis and treatment. The present review attempts to highlight these aspects in the three most identified causative agents of fungal co-infections in COVID-19 patients: Aspergillus, Candida, and Mucorales species.     

Manipulation of genes could inhibit SARS-CoV-2 infection that causes COVID-19 pandemics

The year 2020 witnessed an unpredictable pandemic situation due to novel coronavirus (COVID-19) outbreaks. This condition can be more severe if the patient has comorbidities. Failure of viable treatment for such viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is due to lack of identification. Thus, modern and productive biotechnology-based tools are being used to manipulate target genes by introducing the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas (CRISPR-associated) system. Moreover, it has now been used as a tool to inhibit viral replication. Hence, it can be hypothesized that the CRISPR/Cas system can be a viable tool to target both the SARS-CoV-2 genome with specific target RNA sequence and host factors to destroy the SARS-CoV-2 community via inhibition of viral replication and infection. Moreover, comorbidities and COVID-19 escalate the rate of mortality globally, and as a result, we have faced this pandemic. CRISPR/Cas-mediated genetic manipulation to knockdown viral sequences may be a preventive strategy against such pandemic caused by SARS-CoV-2. Furthermore, prophylactic antiviral CRISPR in human cells (PAC-MAN) along with CRISPR/Cas13d efficiently degrades the specific RNA sequence to inhibit viral replication. Therefore, we suggest that CRISPR/Cas system with PAC-MAN could be a useful tool to fight against such a global pandemic caused by SARS-CoV-2. This is an alternative preventive approach of management against the pandemic to destroy the target sequence of RNA in SARS-CoV-2 by viral inhibition.     

Humoral Immunity against SARS-CoV-2 and the Impact on COVID-19 Pathogenesis

It has been more than a year since severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first emerged. Many studies have provided insights into the various aspects of the immune response in coronavirus disease 2019 (COVID-19). Especially for antibody treatment and vaccine development, humoral immunity to SARS-CoV-2 has been studied extensively, though there is still much that is unknown and controversial. Here, we introduce key discoveries on the humoral immune responses in COVID-19, including the immune dynamics of antibody responses and correlations with disease severity, neutralizing antibodies and their cross-reactivity, how long the antibody and memory B-cell responses last, aberrant autoreactive antibodies generated in COVID-19 patients, and the efficacy of currently available therapeutic antibodies and vaccines against circulating SARS-CoV-2 variants, and highlight gaps in the current knowledge.     

Stopping the COVID-19 pandemic in dental offices: A review of SARS-CoV-2 transmission and cross-infection prevention

Due to the essential role of dentists in stopping the COVID-19 pandemic, the purpose of this review is to help dentists to detect any weaknesses in their disinfection and cross-contamination prevention protocols, and to triage dental treatments to meet the needs of patients during the pandemic. We used PRISMA to identify peer-reviewed publications which supplemented guidance from the center for disease control about infection control and guidelines for dentists. Dentists must triage dental treatments to meet the needs of patients during the pandemic. The ongoing pandemic has changed the practice of dentistry forever, the changes make it more cumbersome, time-consuming, and costly due to the possible pathways of transmission and mitigation steps needed to prevent the spread of COVID-19. Dental chairside rapid tests for SARS-CoV-2 are urgently needed. Until then, dentists need to screen patients for COVID-19 even though 75% of people with COVID-19 have no symptoms. Despite the widespread anxiety and fear of the devastating health effects of COVID-19, only 61% of dentists have implemented a change to their treatment protocols. As an urgent matter of public health, all dentists must identify the additional steps they can take to prevent the spread of COVID-19. The most effective steps to stop the pandemic in dental offices are to; vaccinate all dentists, staff, and patients; triage dental treatments for patients, separate vulnerable patients, separate COVID-19 patients, prevent cross-contamination, disinfect areas touched by patients, maintain social distancing, and change personal protective equipment between patients.     

Fungal Infections in COVID-19 Intensive Care Patients

Opportunistic fungal infections increase morbidity and mortality in COVID-19 patients monitored in intensive care units (ICU). As patients’ hospitalization days in the ICU and intubation period increase, opportunistic infections also increase, which prolongs hospital stay days and elevates costs. The study aimed to describe the profile of fungal infections and identify the risk factors associated with mortality in COVID-19 intensive care patients. The records of 627 patients hospitalized in ICU with the diagnosis of COVID-19 were investigated from electronic health records and hospitalization files. The demographic characteristics (age, gender), the number of ICU hospitalization days and mortality rates, APACHE II scores, accompanying diseases, antibiotic-steroid treatments taken during hospitalization, and microbiological results (blood, urine, tracheal aspirate samples) of the patients were recorded. Opportunistic fungal infection was detected in 32 patients (5.10%) of 627 patients monitored in ICU with a COVID-19 diagnosis. The average APACHE II score of the patients was 28 ± 6. While 25 of the patients (78.12%) died, seven (21.87%) were discharged from the ICU. Candida parapsilosis (43.7%) was the opportunistic fungal agent isolated from most blood samples taken from COVID-19 positive patients. The mortality rate of COVID-19 positive patients with candidemia was 80%. While two out of the three patients (66.6%) for whom fungi were grown from their tracheal aspirate died, one patient (33.3%) was transferred to the ward. Opportunistic fungal infections increase the mortality rate of COVID-19-positive patients. In addition to the risk factors that we cannot change, invasive procedures should be avoided, constant blood sugar regulation should be applied, and unnecessary antibiotics use should be avoided.     

SARS-CoV-2 infection: The role of cytokines in COVID-19 disease

COVID-19 disease, caused by infection with SARS-CoV-2, is related to a series of physiopathological mechanisms that mobilize a wide variety of biomolecules, mainly immunological in nature. In the most severe cases, the prognosis can be markedly worsened by the hyperproduction of mainly proinflammatory cytokines, such as IL-1, IL-6, IL-12, IFN-γ, and TNF-α, preferentially targeting lung tissue. This study reviews published data on alterations in the expression of different cytokines in patients with COVID-19 who require admission to an intensive care unit. Data on the implication of cytokines in this disease and their effect on outcomes will support the design of more effective approaches to the management of COVID-19.     

Opportunistic Candida Infections in Critical COVID-19 Patients

The frequency of opportunistic fungal infections in critically ill patients whose intensive care unit stays are prolonged due to coronavirus disease 2019 (COVID-19) is higher than in the period before COVID-19. We planned this study to improve the management of Candida infections by defining the Candida species, the etiology of infections caused by Candida species, and the antifungal susceptibility of the species. This retrospective study included patients older than 18 hospitalized in the intensive care unit (ICU) with a definitive diagnosis of COVID-19 for seven months (from March 2021 to September 2021). All study data that we recorded in a standard study form were analyzed with TURCOSA (Turcosa Analytics Ltd. Co., Turkey, www.turcosa.com.tr) statistical software. The patients were evaluated in four groups as group 1 (candidemia patients, n = 78), group 2 (candiduria patients, n = 189), group 3 (control patients, n = 57), and group 4 (patients with candidemia in urine cultures taken before Candida was detected in blood culture, n = 42). Candida species were identified using both conventional and VITEK® 2 (BioMérieux, France) methods. The antifungal susceptibility of fungi was determined using the E test method. Of the 5,583 COVID-19 patients followed during the study period, 78 developed candidemia, and 189 developed candiduria. The incidence of candidemia (per 1,000 admissions) was determined to be 1.6. As a result of statistical analysis, we found that Candida albicans was the dominant strain in candidemia and candiduria, and there was no antifungal resistance except for naturally resistant strains. Candida strains grown in blood and urine were the same in 40 of 42 patients. Mortality was 69.2% for group 1, 60.4% for group 2, and 57.8% for group 3. Antifungals were used in 34 (43.5%) patients from group 1, and 95 (50.2%) from group 2. In the candidemia group without antifungal use, mortality was quite high (77.2%). Antifungal use reduced mortality in the group 2 (p < 0.05). Length of ICU stays, comorbidity, broad-spectrum antibiotics, and corticosteroids are independent risk factors for candidemia in critically ill COVID-19 patients. Our study contributes to the knowledge of risk factors for developing COVID-19-related candida infections. The effect of candiduria on the development of candidemia in critically ill COVID-19 patients should be supported by new studies.     

Recipients of COVID-19 vaccines face challenges of SARS-CoV-2 variants

The coronavirus disease 19 (COVID-19) has been rampant since 2019, severely affecting global public health, and causing 5.75 million deaths worldwide. So far, many vaccines have been developed to prevent the infection of SARS-CoV-2 virus. However, the emergence of new variants may threat vaccine recipients as they might evade immunological surveillance that depends on the using of anti-SARS-CoV-2 antibody to neutralize the viral particles. Recent studies have found that recipients who received two doses of vaccination plus an additional booster shoot were able to quickly elevate neutralization response and immune response against wild-type SARS-CoV-2 virus and some initially appeared viral variants. In this review, we assessed the real-world effectiveness of different COVID-19 vaccines by population studies and neutralization assays and compared neutralization responses of booster vaccines in vitro. Finally, as the efficacy of COVID-19 vaccine is expected to decline over time, continued vaccination should be considered to achieve a long-term immune protection against coronavirus.     

Cystic fibrosis improves COVID-19 survival and provides clues for treatment of SARS-CoV-2

Systemic pools of ATP are elevated in individuals homozygous for cystic fibrosis (CF) as evidenced by elevated blood and plasma ATP levels. This elevated ATP level seems to provide benefit in the presence of advanced solid tumors (Abraham et al., Nature Medicine 2(5):593–596, 1996). We published in this journal a paper showing that IV ATP can elevate the depleted ATP pools of advanced cancer patients up to levels found in CF patients with subsequent clinical, biochemical, and quality of life (QOL) improvements (Rapaport et al., Purinergic Signalling 11(2): 251–262, 2015). We hypothesize that the elevated ATP levels seen in CF patients may be benefiting CF patients in another way: by improving their survival after contracting COVID-19. We discuss here the reasoning behind this hypothesis and suggest how these findings might be applied clinically in the general population.     

新型冠状病毒的相关研究进展

2019年12月出现于湖北武汉的一种新型冠状病毒(SARS-CoV-2)感染所致肺炎疫情,给人类生命安全造成威胁。迄今为止,对2019年出现的SARS-CoV-2的研究仍处于起步阶段,本文就其相关研究进展进行综述,重点阐述了目前关于SARS-CoV-2的病原学与致病机制方面的研究成果,同时对其流行病学以及该病毒引发的肺炎临床特点加以总结,有助于读者及时了解SARS-CoV-2最新的研究动态,并为今后开展治疗药物及疫苗研发提供方向。     

SARS-CoV-2 associated COVID-19 in geriatric population: A brief narrative review

Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), has emerged as a fatal pandemic and has crushed even the world’s best healthcare systems. Globally, it has affected 40,373,228 individuals and resulted in 1,119,568 deaths as of October 19, 2020. Research studies have demonstrated that geriatric population is vastly vulnerable to COVID-19 morbidity and mortality given their age and preexisting chronic comorbidities such as cardiovascular disease, hypertension, diabetes mellitus, chronic pulmonary and chronic kidney disease The data regarding susceptibility of elderly population to COVID-19 is accruing and suggests that factors like age, gender, chronic comorbidity, inflammaging, immunosenescence and renin angiotensin system may be the contributing risk factors towards COVID-19 and associated mortality in elderly population. Based on updated scientific literature, this narrative review précises the clinical presentations and underlying risk factors that might be associated with COVID-19 morbidity in geriatric population and provides informed insights, and discusses clinical presentation, psychosocial impact, mortality and potential corticosteroid treatment and prevention strategies of COVID-19 in older adults.