How antibodies target coronavirus
December 3, 2021 - People who have recovered from mild coronavirus infections produce antibodies that target three different parts of the virus’s spike protein that it uses to latch on to human cells.
A National Institutes of Health-funded study, published recently in the journal Science, offers the most detailed picture yet of the array of antibodies against SARS-CoV-2 found in people who’ve fully recovered from mild cases of coronavirus.
Most studies of natural antibodies that block coronavirus have focussed on those that target a specific portion of the spike protein known as the receptor-binding domain (RBD). The RBD is the portion of the spike that attaches directly to human cells. As a result, antibodies explicitly targeting the RBD are an excellent place to begin searching for antibodies capable of fighting the virus.
However, researchers at The University of Texas at Austin found that most antibodies target other portions of the spike protein than the RBD.
The study, led by Gregory Ippolito and Jason Lavinder, likens the spike protein to an umbrella, with the RBD at the tip of the “canopy.” While some antibodies bind to the RBD, many others target the protein’s canopy, known as the N-terminal domain (NTD).
The team also found that about 40 per cent of antibodies target yet another portion of the spike called the S2 subunit. Additionally, the S2 subunit could make an ideal target for a possible pan-coronavirus vaccine since fewer mutations exist at this portion of the spike.
The study will prove helpful in designing vaccine booster shots or future vaccines tailored to fight coronavirus variants of concern.