First-of-Its-Kind Antibody Test Measures Degree of Immunity from COVID-19

By LabMedica International staff writers
Posted on 06 Apr 2022

Image: COVID-19 Immune Index monitors effectiveness of COVID-19 virus protection through a simple blood test (Photo courtesy of KSL Diagnostics)

People have a need to clearly understand their level of risk for COVID-19 infection and potential complications. Now, a first-of-its-kind antibody test detects an individual’s immune response to COVID-19 and assesses the risk of infection if subsequently exposed.

KSL Diagnostics, Inc. (Buffalo, NY, USA) has launched the COVID-19 Immune Index which can help monitor the effectiveness of COVID-19 virus protection through a simple blood test. The new assay correlates COVID-19 virus neutralization against a person’s antibody levels. The highly accurate test measures antibodies specific to COVID-19 which develop in response to vaccination or infection and correlates these results with virus neutralization studies incorporating the significant COVID-19 virus strains to date. The new test provides physicians and their patients an objective datapoint to help determine appropriate timing for booster vaccine doses and making informed decisions related to potential COVID-19 exposure. The test will be valuable for monitoring the immunity levels of nursing home and long-term care residents, veterans living in group housing, and patients undergoing treatment for cancer, organ transplants, or serious chronic illnesses, among others.

KSL has completed studies on the relevance of circulating antibodies in vaccinated individuals in order to determine the optimal neutralizing antibody titers required to block virus entry into host cells by utilizing a plaque reduction neutralization test (PRNT), the “gold-standard” for assessing virus deactivation and correlating these results with the company’s antibody assays. The results demonstrated stratification of immunity. For example, 100% neutralization of the virus was seen at IgG levels of 20 and above, suggesting adequate immunity. IgG levels from 10-20 reduced effective virus neutralization by 25%, while IgG levels below 10 indicated considerably decreased neutralization, suggesting ineffective immunity.

“There is a lot of variability in antibody levels over time after infection, vaccination and boosters. Guidance is constantly changing, but good tools to help people better understand their immune status have not been available,” says Kevin Lawson, President and CEO of KSL. “The COVID-19 Immune Index provides an accurate report for those who are immunocompromised, at risk with co-morbidities, re-entering the workplace or traveling. Understanding your level of immunity can provide peace of mind as we move past the pandemic.”

“The ability to correlate COVID-19 neutralizing antibody titers, especially IgG titers, with antibody assays to accurately assess an individual’s level of protection from COVID over time is a breakthrough development that will help us better navigate the pandemic as it transitions to endemic,” said Dr. Amy Jacobs of the University at Buffalo which collaborated with KSL for the study. “Because KSL’s COVID-19 Immune Index™ test compares well with the industry-standard PRNT assay but is better suited to high throughput testing, physicians will be able to conduct large scale community testing to monitor declining immunity in specific populations and actively promote boosters to curb new surges of the disease.”

Related Links:
KSL Diagnostics, Inc.