Rapid quantitative electrochemical detection of SARS-CoV-2 antibodies in plasma and dried blood spot samples (preprint)

Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is a highly contagious disease with several variants, continues to spread as part of the global pandemic. With the roll-out of vaccines and development of new therapeutics that may be targeted to distinct viral molecules, there is a need to screen populations for viral antigen-specific SARS-CoV-2 antibodies. Here, we describe a rapid, multiplexed, electrochemical (EC) platform with on-chip control that enables detection of SARS-CoV-2 antibodies in less than 10 min using 1.5 microliter of a patient sample. The EC biosensor demonstrated 100% sensitivity and specificity, and an area under the receiver operating characteristic curve of 1, when evaluated using 93 clinical samples, including plasma and dried blood spot samples from 54 SARS-CoV-2 positive and 39 negative patients. This EC biosensor platform enables simple, cost-effective, sensitive, and rapid detection of anti-SARS-CoV-2 antibodies in complex clinical samples, which is convenient for monitoring host humoral responses to vaccination or viral infection in broad population testing, including applications in low-resource settings. We also demonstrate the feasibility of using dried blood spot samples that can be collected locally and transported to distant clinical laboratories at ambient temperature for detection of anti-SARS-CoV-2 antibodies which can be used for serological surveillance and demonstrate the utility of remote sampling.

Evaluating the utility of interleukin-6, c -reactive protein (CRP) and procalcitonin in predicting disease severity and prognosis in hospitalized SARS-CoV-2 patients: a north Indian retrospective study. (Special issue.)

Background: Coronavirus disease 2019 (COVID-19) associated inflammatory cytokine storm that worsens COVID-19, relies heavily on the inflammatory response. IL-6, a TH1 cytokine, PCT and CRP have been linked to serious illness and a higher mortality rate. We further tried to evaluate the role of these indicators and their association with clinical severity in COVID-19 patients. Material and Methods: Eighty-three consecutive patients with age 18 years with RT-PCR test positive for SARS-CoV-2 were included in the study. Demographic characteristics (age and sex), underlying co-morbidities, symptoms, physical findings, and laboratory tests of the patients were recorded. All patients were categorized as having mild, moderate, and severe COVID-19 disease, according to the Indian Council of Medical Research (ICMR). The levels of IL-6 and PCT were estimated by electrochemiluminescence immunoassay (ECLIA) using Cobas-e411 Immunoassay System, and Quantitative CRP was done by Unicorn-230 automated biochemistry analyzer to find out their correlation with disease severity and outcome. Multiple Regression was performed to find out factors associated with the adverse outcome of the disease. Result: Mean age of patients was 51 years. IL-6, CRP, and PCT levels increased in 73%, 68.0%, and 8.2% patients on admission, respectively. The most common co-morbidity associated with the disease was hypertension (25%), followed by diabetes (24%) and respiratory disease (15%). Increased IL-6, CRP, and PCT levels were found in 77 percent, 79 percent, and 20 percent of patients, respectively. We found that IL-6 (P0.05), CRP (P0.05), and PCT (P0.05) were significantly raised in COVID-19 patients with increasing severity of the disease. The Area under the receiver operating characteristic (AUROC) of these parameters ranged between 0.65 and 0.8 (IL-6, 0.828;CRP, 0.809;and PCT, 0.658), indicating a reliable biomarker to assess clinical severity.

Guillain-Barré syndrome following COVID-19 infection in an elderly patient: a case report

Background: Coronaviruses can affect multiple body systems and respiratory failure is the most common complication. Since the outbreak of coronavirus disease-2019 (COVID-19) in January 2020, the association between COVID-19 and Guillain-Barre syndrome (GBS) has been growing. GBS is known to be triggered by an antecedent infection, mostly viruses. Case Presentation: We present a case of GBS in an 83-year-old female patient with a confirmed COVID-19 infection. The patient initially presented with fever, cough, and fatigue. She was treated with intravenous fluid and symptomatic treatment and discharged home after stabilization. Several weeks after her initial encounter, she experienced bilateral paresthesias as well as numbness and tingling in her lower extremities. The patient's neurological symptoms were not alleviated with standard intravenous immune globulin (IVIG) therapy;however, her symptoms significantly improved with subsequent plasmapheresis therapy. Conclusion: Based on the emerging evidence of recent studies, there is a possible connection between COVID-19 and GBS. Clinicians should be aware of the neurological manifestations of COVID-19 infection. Early diagnosis and proper treatment of COVID-19 and its neurological symptoms are crucial to increase the chance of a successful recovery.

Enteric coronavirus infection and treatment modeled with an immunocompetent human intestine-on-a-chip (preprint)

Many patients infected with coronaviruses, such as SARS-CoV-2 and NL63 that use ACE2 receptors to infect cells, exhibit gastrointestinal symptoms and viral proteins are found in the human gastrointestinal tract, yet little is known about the inflammatory and pathological effects of coronavirus infection on the human intestine. Here, we used a human intestine-on-a-chip (Intestine Chip) microfluidic culture device lined by patient organoid-derived intestinal epithelium interfaced with human vascular endothelium to study host cellular and inflammatory responses to infection with NL63 coronavirus. These organoid-derived intestinal epithelial cells dramatically increased their ACE2 protein levels when cultured under flow in the presence of peristalsis-like mechanical deformations in the Intestine Chips compared to when cultured statically as organoids or in Transwell inserts. Infection of the intestinal epithelium with NL63 on-chip led to inflammation of the endothelium as demonstrated by loss of barrier function, increased cytokine production, and recruitment of circulating peripheral blood mononuclear cells (PMBCs). Treatment of NL63 infected chips with the approved protease inhibitor drug, nafamostat, inhibited viral entry and resulted in a reduction in both viral load and cytokine secretion, whereas remdesivir, one of the few drugs approved for COVID19 patients, was not found to be effective and it also was toxic to the endothelium. This model of intestinal infection was also used to test the effects of other drugs that have been proposed for potential repurposing against SARS-CoV-2. Taken together, these data suggest that the human Intestine Chip might be useful as a human preclinical model for studying coronavirus related pathology as well as for testing of potential anti-viral or anti-inflammatory therapeutics.

Virtual Screening of Naturally Occurring Antiviral Molecules for SARS-CoV-2 Mitigation Using Docking Tool on Multiple Molecular Targets (preprint)

The coronavirus catastrophe (COVID-19) caused by a novel strain of coronavirus (SARS-CoV-2) has turned the world upside down at an unprecedented level and has been declared as a pandemic by World Health Organization (WHO). It has resulted huge number of fatalities and infections due to the severe lower respiratory tract sickness in the infected people. Research across the world is in progress to identify inhibitors against various molecular targets associated with this viral infection. Among these targets, a very important one is a cysteine like protease or 3CL protease (3CLpro) and that is required for the replication of the virus. In the present study, initially we have investigated the potential of twenty naturally occurring antiviral molecules to function as inhibitors against the activity of main viral protease (3CLpro) so as to put a halt on viral replication. The investigation has been carried out through docking of the molecules with 3CLpro. Based on the results, three most potential molecules (bilobetin, ginkgetin and sciadopitysin) have been screened. Further these molecules were subjected for checking their activity on other molecular targets like a papain like protease (PLpro), spike protein S1, RNA dependent RNA polymerase (RdRp), angiotensin converting enzyme 2 (ACE2) receptor. In addition to 3CLpro inhibition, ginkgetin was predicted as an inhibitor of PLpro also. But none of these three compounds was found effective on rest other molecular targets.