A recent study reveals some patients have antibodies that stop the virus from attaching to host cells, prevent the virus from replicating, and provide immunity.
In the study "Detection of SARS-CoV-2-specific humoral and cellular immunity in COVID-19 convalescent individual," the researchers discovered that antibodies stayed in their patients at least two weeks after they were discharged from the hospital.
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Unique cases
SARS-CoV-2 stands for Severe Acute Respiratory Syndrome Coronavirus 2, the virus that causes the Coronavirus Disease 2019 (COVID-19).
As of May 7, the COVID-19 pandemic has 3.77 million confirmed cases, 1.25 million recoveries, and 264,000 fatalities worldwide.
The newest epicenter of COVID-19 after China and Italy, the United States of America has nearly one-third of the total cases at 1.26 million, 171,000 recoveries, and over 75,000 deaths.
Published in the journal Immunity, the study's co-senior author Dr. Chen Song said, "These findings suggest both B and T cells participate in immune-mediated protection against the viral infection."
Dr. Song is the Dean of the School of Medicine of Tsinghua University in Beijing, China. Tsinghua University leads the team in studying more about antibodies.
The Daily Mail said the study suggests "that antibodies were maintained for at least that long - welcome news considering little is known about the new virus."
Knowing more about antibodies may speed up the development of a vaccine for COVID-19. Dr. Song said their study has implications to help other scientists in designing a vaccine.
"Our work has provided a basis for further analysis of protective immunity and for understanding the mechanism underlying the development of COVID-19, especially in severe cases," Dr. Song said.
Checking up on former COVID-19 patients
The researchers studied 14 patients who have recovered from COVID-19. They also included six control patients.
Eight patients were discharged recently, while six were discharged from the hospital two weeks before. Their blood samples were collected and checked for their level of immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies.
IgM were the first to appear, while IgG were the most common. According to the Daily Mail, "In comparison with the control group, all 14 patients had higher levels of both IgM and IgG antibodies."
The results also showed COVID-19 patients have an immune response to SARS CoV-2 for two weeks. Five from those newly discharged had higher levels of T cells.
T cells are "a signaling molecule that plays a role in immunity. Three of the patients had T-cells that secreted a molecule that protects the virus from replicating within the body," the Daily Mail said.
Meanwhile, seven out of the eight patients had antibodies that prevented SARS-CoV-2 from attaching to receptors on human cells and invading them.
Some patients possessed all three antibodies, while others only had one. The team will confirm these in a future study that will have more patients.
