Christina A. Rostad and colleagues, from Emory University and the University of Texas Medical Branch, Galveston found that children with MIS-C has substantially higher levels of antibodies against the receptor binding domain (RBD) a specific part of the novel coronavirus' spike protein that allows the virus to invade cells.
The findings suggest that a stronger immune response against RBD could be associated with MIS-C, either as an indicator or possibly in a form of casual relationship.
In a commentary of Rostad's work, Steven Zeichner, MD, PhD, of University of Virginia Children's and Andrea Cruz, MD, of Baylor College of Medicine in Houston noted that the discovery concerning the higher levels of antibodies could help in diagnosing MIS-C.
If antibodies against RBD contribute to causing MIS-C, there may be a subtype or amount of antibodies against RBD that are unhelpful or even dangerous. Doctors may need to consider this when treating COVID-19 patients.
RBD is a component of many COVID-19 vaccines being developed, making the new findings potentially important there as well. If some antibodies against RBD are associated with MIS-C or increased inflammation, it would be essential to carefully evaluate subjects in vaccine trials for evidence of increased inflammatory responses, especially if and when these subjects are exposed to and infected with the coronavirus.
This consideration is an important reminder that the rush for a vaccine shouldn't preclude the need for thorough testing, wrote Zeichner and Cruz.
“There are 200+ vaccines at various stages of development out there, and I think that the deeper implication of the finding … is that we need to be careful about potential safety concerns, which will need to be considered during the development of the vaccines,” Zeichner said, according to a press release by the University of Virginia.
Zeichner warned that public trust and enthusiasm to get the vaccine depends on the public's faith in the safety of any vaccine.
“We do not want to have a situation where patients do not have confidence that a vaccine is safe, nor do we want a vaccine to be prematurely approved and prove later to have significant safety concerns,” he said. “Such problems could ultimately do a disservice to the cause of controlling the pandemic. Potentially, people would not trust any COVID-19 vaccine, or even perhaps other vaccines.”
US President Donald Trump said on Wednesday he may or may not approve potentially new, more stringent standards for an emergency authorization of a COVID-19 vaccine by the US Food and Drug Administration, saying such a move would appear political.
The Washington Post reported on Tuesday the FDA would issue the guidance to boost transparency and public trust as health experts have become increasingly concerned the Trump administration might be interfering in the approval process.
Reuters contributed to this report.