Developmental Biology - COVID-19 Virus Antibody Test|
Antibody Test For COVID-19 Virus Breakthrough
Several tests have been developed for detecting genes causing COVID-19, but only during acute infection...
Antibodies are specialized proteins that help clear the body of invading microbes. Made by immune cells known as B cells shortly after infection, antibodies specifically recognize pathogens, binding to the surfaces of viruses and stopping them from entering cells, for example, or marking them for destruction by other parts of the immune system.
The proteins don’t exist until at least a few days into an acute infection, and often aren’t detectable until a week or more after symptoms appear, Rangarajan Sampath, the chief scientific officer of the nonprofit Foundation for Innovative New Diagnostics.
Several tests have been developed for detecting the genetic material of the SARS-CoV-2 coronavirus that causes COVID-19. But, they generally only allow detection of the virus during acute infection. Antibody, or serological, tests are urgently needed to determine the real rate of infection.
Understanding each individuals' antibody
responses to the virus, identifies those
people potentially immune to re-infection.
Investigators have now developed such a test! It is described in their paper published in Current Protocols in Microbiology.
The article gives a step-by-step protocol with enough detail that other researchers can replicate the process in their own laboratories. The protocol involves expressing and purifying segments of a key SARS-CoV-2 protein, then used in blood tests to detect the presence of antiviral antibodies.
"Serological assays can be used to identify individuals who were infected (including severe, mild, and asymptomatic cases) and who are now potentially immune, which means that they are unlikely to transmit the virus to others.
As an example, healthcare workers who are immune could potentially care for COVID19 patients with minimal risk to themselves, their colleagues, and other patients."
In late 2019, cases of atypical pneumonia were detected in China. The etiological agent was quickly identified as a betacoronavirus (named SARS-CoV-2), which has since caused a pandemic. Several methods allowing for the specific detection of viral nucleic acids have been established, but these only allow detection of the virus during a short period of time, generally during acute infection. Serological assays are urgently needed to conduct serosurveys, to understand the antibody responses mounted in response to the virus, and to identify individuals who are potentially immune to re-infection. Here we describe a detailed protocol for expression of antigens derived from the spike protein of SARS-CoV-2 that can serve as a substrate for immunological assays, as well as a two-stage serological enzyme-linked immunosorbent assay (ELISA). These assays can be used for research studies and for testing in clinical laboratories. © 2020 The Authors. Current Protocols in Microbiology published by Wiley Periodicals LLC.
• Basic Protocol 1: Mammalian cell transfection and protein purification
• Basic Protocol 2: A two-stage ELISA for high-throughput screening of human serum samples for antibodies binding to the spike protein of SARS-CoV-2
Daniel Stadlbauer, Fatima Amanat, Veronika Chromikova, Kaijun Jiang, Shirin Strohmeier, Guha Asthagiri Arunkumar, Jessica Tan, Disha Bhavsar, Christina Capuano, Ericka Kirkpatrick, Philip Meade, Ruhi Nichalle Brito, Catherine Teo, Meagan McMahon, Viviana Simon, Florian Krammer.
The authors thank Dr. Raffael Nachbagauer (Icahn School for Medicine at Mount Sinai) and Dr. Aubree Gordon (University of Michigan) for critical reading and constructive comments. Development of this protocol was partially supported by the NIAID Centers of Excellence for Influenza Research and Surveillance (CEIRS) contract HHSN272201400008C.
Philanthropic donations in support of our work are much appreciated, since the reagents are shared free of charge with the scientific community. Please contact Vanesa Saric (firstname.lastname@example.org) for further information.
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Apr 27 2020 Fetal Timeline Maternal Timeline News
A new serological assay can identify individuals infected by covidvirus — including severe, mild, and asymptomatic cases. People who are potentially immune, are unlikely to transmit the virus to others.