Does getting vaccinated, or having recovered from COVID, provide life-long protection against the coronavirus? Most likely, says research by immunologists at Washington University in St. Louis, who found antibody-producing cells against the virus residing in the bone marrow of individuals who had previously tested COVID-positive.
This discovery supports the theory that immune responses after exposure to SARS-CoV-2 are robust enough to confer sustained, potentially decades-long protection against the pathogen. In addition, this finding also indicates that vaccines may create a similarly durable shield against COVID in the long run.
Antibody-producing bone marrow plasma cells, or BMPCs, are among the body’s arsenal of immune weapons against invading pathogens, forming a part of what’s known as immunological memory. When the immune system comes across a microbiological threat that it has encountered previously, it launches a more rapid, aggressive, and targeted attack against the offending microbe the second time around.
Earlier studies had suggested that BMPC formation might not occur as effectively in COVID patients as it does in the case of other viral infections, meaning that those who have recovered from COVID may be at risk of reinfection.
However, a study led by BMPC expert Ali Ellebedy found the opposite to be true. The researchers’ analysis of samples obtained from 77 COVID-19 patients revealed that these individuals continued to produce antibodies specific to SARS-CoV-2 up to 11 months after infection. Additionally, 15 of the 18 bone marrow samples collected from these participants showed the presence of coronavirus-specific BMPCs at around a year after infection.
The scientists speculate that vaccines may elicit similar immunological responses, although the emergence of novel variants of SARS-CoV-2 may leave vaccinated individuals vulnerable and in need of “booster” shots for complete protection.