biostudies-literatureVangeti SDOD | Defense Health AgencySwedish Research CouncilDOD | Defense Advanced Research Projects Agencye0183722https://www.ebi.ac.uk/biostudies/studies/S-EPMC9769986biostudies-literatureUnknown10(6)We investigated the temporal profile of multiple components of the serological response after asymptomatic or mildly symptomatic SARS-CoV-2 infection, in a cohort of 67 previously SARS-CoV-2 naive young adults, up to 8.5 months after infection. We found a significant decrease of spike IgG and neutralization antibody titers from early (11 to 56 days) to late (4 to 8.5 months) time points postinfection. Over the study period, S1-specific IgG levels declined significantly faster than that of the S2-specific IgG. Further, serum antibodies from PCR-confirmed participants cross-recognized S2, but not S1, of the betacoronaviruses HKU1 and OC43, suggesting a greater degree of cross-reactivity of S2 among betacoronaviruses. Antibody-Dependent Natural Killer cell Activation (ADNKA) was detected at tMicrobiology spectrumSerum Fc-Mediated Monocyte Phagocytosis Activity Is Stable for Several Months after SARS-CoV-2 Asymptomatic and Mildly Symptomatic Infection.PMC9769986N6600119C40222021-067139700130Balinsky CAPeriasamy SSugiharto VANunez EVangeti SMarayag JGoforth CWGeorge MCSun PYu XBMarrone AGe YSoares-Schanoski AJani VSchilling MLetizia AGBukreyev AMahajan ASLizewski RMarjanovic NRamos ISealfon SCCooper EPorter CKKuzmina NABeckett CLizewski SEfalseSerum Fc-Mediated Monocyte Phagocytosis Activity Is Stable for Several Months after SARS-CoV-2 Asymptomatic and Mildly Symptomatic Infection.We investigated the temporal profile of multiple components of the serological response after asymptomatic or mildly symptomatic SARS-CoV-2 infection, in a cohort of 67 previously SARS-CoV-2 naive young adults, up to 8.5 months after infection. We found a significant decrease of spike IgG and neutralization antibody titers from early (11 to 56 days) to late (4 to 8.5 months) time points postinfection. Over the study period, S1-specific IgG levels declined significantly faster than that of the S2-specific IgG. Further, serum antibodies from PCR-confirmed participants cross-recognized S2, but not S1, of the betacoronaviruses HKU1 and OC43, suggesting a greater degree of cross-reactivity of S2 among betacoronaviruses. Antibody-Dependent Natural Killer cell Activation (ADNKA) was detected at t2022-01-01T00:00:00Z2022 Dec2026-06-12T09:51:53.933Z2025-04-05T14:54:51.62ZS-EPMC97699863637404010.1128/spectrum.01837-22