A study by researchers in Texas describes a mouse model in which a subunit vaccine with alum-CpG adjuvant was tested for its ability to induce a broadly neutralizing antibody response against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
A new study published in the journal mBio investigates different antibodies from convalescent donors that bind three separate domains of the SARS-CoV-2 spike. The results of this study suggest that the individuals exposed to the SARS-CoV-2 from the first wave have neutralizing antibodies against current variants.
n = 80) from the Amsterdam Cohort Studies on HIV infection and AIDS (ACS) were used to analyze HIV-specific antibody glycosylation. Peripheral blood samples used to purify CMV-specific antibodies (
n = 102) were from same cohort as used for HPA-1a collected by the Finnish Red Cross Blood service, Platelet Immunology Laboratory, Helsinki, Finland and the HIV cohort described above. SARS-CoV-2 patient samples from ICU patients from the Amsterdam UMC COVID study group were included, as well as Sanquin blood donors found seropositive for SARS-CoV-2, and mild longitudinal samples from hospital workers monitored after potential exposure (
26). A summary of the patients demographics is found in table S1, and detailed patient treatments of the ARDS COVID-19 patients in table S2 (all requiring ventilation). The ACS have been conducted in accordance with the ethical principles set out in the declaration of Helsinki and all participants provided written informed consent. The study was approve
IgG antibodies are crucial for protection against invading pathogens. A highly conserved N-linked glycan within the IgG-Fc tail, essential for IgG function, shows variable composition in humans. Afucosylated IgG variants are already used in anti-cancer therapeutic antibodies for their elevated activity through Fc receptors (FcγRIIIa). Here, we report that afucosylated IgG (~6% of total IgG in humans) are specifically formed against enveloped viruses but generally not against other antigens. This mediates stronger FcγRIIIa responses, but also amplifies brewing cytokine storms and immune-mediated pathologies. Critically ill COVID-19 patients, but not those with mild symptoms, had high levels of afucosylated IgG antibodies against SARS-CoV-2, amplifying pro-inflammatory cytokine release and acute phase responses. Thus, antibody glycosylation plays a critical role in immune responses to enveloped viruses, including COVID-19.
Afucosylated IgG characterizes enveloped viral responses and correlates with COVID-19 severity sciencemag.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from sciencemag.org Daily Mail and Mail on Sunday newspapers.