Abstract:
Among the unknowns in decoding the pathogenesis of SARS-CoV-2 persistent symptoms in Long Covid is whether there is a contributory role of abnormal immunity during acute infection. It has been proposed that Long Covid is a consequence of either an excessive or inadequate initial immune response.
Here, we analyze SARS-CoV-2 humoral and cellular immunity in 86 healthcare workers with laboratory confirmed mild or asymptomatic SARS-CoV-2 infection during the first wave. Symptom questionnaires allow stratification into those with persistent symptoms and those without for comparison.
During the period up to 18-weeks post-infection, we observe no difference in antibody responses to spike RBD or nucleoprotein, virus neutralization, or T cell responses. Also, there is no difference in the profile of antibody waning. Analysis at 1-year, after two vaccine doses, comparing those with persistent symptoms to those without, again shows similar SARS-CoV-2 immunity. Thus, quantitative differences in these measured parameters of SARS-CoV-2 adaptive immunity following mild or asymptomatic acute infection are unlikely to have contributed to Long Covid causality. ClinicalTrials.gov (NCT04318314).
Source: Altmann DM, Reynolds CJ, Joy G, Otter AD, Gibbons JM, Pade C, Swadling L, Maini MK, Brooks T, Semper A, McKnight Á, Noursadeghi M, Manisty C, Treibel TA, Moon JC; COVIDsortium investigators; Boyton RJ. Persistent symptoms after COVID-19 are not associated with differential SARS-CoV-2 antibody or T cell immunity. Nat Commun. 2023 Aug 23;14(1):5139. doi: 10.1038/s41467-023-40460-1. PMID: 37612310; PMCID: PMC10447583. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10447583/ (Full text)