Most newly discharged patients who recently recovered from COVID-19 produce virus-specific antibodies and T cells, suggests a new study.
However, it goes on to state that the responses of different patients are not all the same.
The 14 patients examined in the study showed wide-ranging immune responses.
But results from the six who were assessed at two weeks after discharge suggest that antibodies were maintained for at least that long.
Additional results from the study indicate which parts of the virus are most effective at triggering these immune responses and should, therefore, be targeted by potential vaccines.
It is not clear why immune responses varied widely across the patients. The authors say this variability may be related to the initial quantities of virus that the patients encountered, their physical states, or their microbiota.
Other open questions include whether these immune responses protect against COVID-19 upon re-exposure to SARS-CoV-2, as well as which types of T cells are activated by infection with the virus.
It is also important to note that the laboratory tests that are used to detect antibodies to SARS-CoV-2 in humans still need further validation to determine their accuracy and reliability.
Chen Dong of Tsinghua University, one of the co-authors, said: “These findings suggest both B and T cells participate in immune-mediated protection against the viral infection.
“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. It also has implications for designing an effective vaccine.”
