Characterization of the antibody response to SARS‐CoV‐2 in a mildly affected pediatric population

Abstract

Background While children usually experience a mild course of COVID‐19, and a severe disease is more common in adults, the features, specificities, and functionality of the SARS‐CoV‐2‐specific antibody response in the pediatric population are of interest. Methods We performed a detailed analysis of IgG antibodies specific for SARS‐CoV‐2‐derived antigens S and RBD by ELISA in 26 SARS‐CoV‐2 seropositive schoolchildren with mild or asymptomatic disease course, and in an equally sized, age‐ and gender‐matched control group. Furthermore, a detailed mapping of IgG reactivity to a panel of microarrayed SARS‐CoV‐2 proteins and S‐derived peptides was performed by microarray technology. The capacity of the antibody response to block RBD‐ACE2 binding and virus neutralization were assessed. Results were compared with those obtained in an adult COVID‐19 convalescent population. Results After mild COVID‐19, anti‐S and RBD‐specific IgG antibodies were developed by 100% and 84.6% of pediatric subjects, respectively. No difference was observed in regards to symptoms and gender. Mounted antibodies recognized conformational epitopes of the spike protein and were capable to neutralize the virus up to a titer of ≥80 and to inhibit the ACE2‐RBD interaction by up to 65%. SARS‐CoV‐2‐specific IgG responses in children were comparable to mildly affected adult patients. Conclusion SARS‐CoV‐2 asymptomatic and mildly affected pediatric patients develop a SARS‐CoV‐2‐specific antibody response, which is comparable regarding antigen, epitope recognition, and the ability to inhibit the RBD‐ACE2 interaction to that observed in adult patients after mild COVID‐19.

SARS-CoV-2 seroprevalence and determinants for salivary seropositivity among pupils and school staff: a prospective cohort study

“…5 Excluding six (1%) samples with insufficient volume. 6 Excluding two (0.5%) samples with insufficient volume. LTFU, lost to follow-up; no data available after this period.…”

“…Vaccination became available in August 2021 for the population between ages 12 and 17, and was recommended for all children below 18 by the end of December 2021. [4][5] Representative national studies investigating the seroprevalence in pupils and school staff, assessing past-infection rates, [6] are scarce. [7] Estimates from left-over laboratory samples [8] in the paediatric population lack generalizability and do not provide the necessary context to assess determinants of infection.…”

“…Representative national studies investigating seroprevalence in pupils and school staff and assessing past infection rates [ 6 ] are scarce [ 7 ]. Estimates from leftover laboratory samples [ 8 ] in the paediatric population lack generalizability and do not provide the necessary context to assess determinants of infection.…”

Mast cells—fetal mast cells crosstalk with maternal interfaces during pregnancy: Friend or foe?

“…MC contribute to orchestrating an immune response against external insults such as parasites and viral infections 71 . Since fMC exhibit a similar phenotype of expressed receptors during pregnancy compared with adult MC (Table 1), then it is important to include fMC subsets in the research investigating the impact of the exposure of pregnant mothers to infections on the immunity of the offspring, and its involvement in acquiring specific antibodies against these pathogens in the fetal environment hence reshaping the neonatal immunity after birth 43,46,72‐76 …”

“…and its involvement in acquiring specific antibodies against these pathogens in the fetal environment hence reshaping the neonatal immunity after birth. 43,46,[72][73][74][75][76] Vertical transfer of immunoglobulins and allergens from mother…”