The COVID-19 modelna vaccine provokes an important antibody response among children

In a recent article published in Scientific translation medicine Journals and researchers have shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger ribonucleic acid (mRNA) vaccination causes a strong antibody response in children.

Background

They often bear a higher burden of respiratory infections because the infant’s immune system is not yet developed and trained. Outbreaks of coronavirus disease 2019 (COVID-19) were rare in children, but due to the emergence of highly infectious SARS-CoV-2 variants (VOCs) such as Omicron, reopening of schools, and changes in mask regulations, SARS Increased-CoV-2 infection in children. Therefore, it is important to vaccinate children of all ages with COVID-19.

Nevertheless, it is still unclear whether children respond to SARS-CoV-2 mRNA vaccination like adults, and whether the recommended dose produces optimal immunity.

About research

In this study, researchers attempted to characterize an adult (100 μg) or pediatric (50 μg) dose-induced humoral immune response of the COVID-19 modelna mRNA-1273 vaccine in children aged 6 to 11 years. I did. They compared these reactions. Children infected with SARS-CoV-2, vaccinated adults, and Pediatric multisystem inflammatory syndrome (MIS-C).

In addition, subjects received two doses of the Moderna vaccine at doses of 100 μg and 50 μg. Plasma samples were taken before vaccination (V0), approximately 4 weeks after the first vaccination (V1), and 4 weeks after the second vaccination (V2).

Scientists have examined SARS-CoV-2 peplomer (S) protein-specific antibody titers to assess the humoral response evoked by the vaccine. They characterized the relative possibility that a vaccine-induced immune response would attach to human fragment crystallizable (Fc) receptors (FcγR2b, FcγR2a, FcγR3a, FcαR, and FcγR3b). In addition, researchers have found that antibody-dependent neutrophil phagocytosis (ADNP), antibody-dependent complement deposition (ADCD), antibody-dependent natural killer cell activation (ADNKA), or antibody-dependent monocyte phagocytosis (ADNKA). We investigated how well ADCP) can be induced.

Next, the authors examined vaccine-induced Fc effector activity to see if these different pediatric Fcγ receptor attachment patterns were converted to a more functional humoral immune response selective for S proteins. I confirmed. In addition, machine learning strategies were used to investigate the most variable characteristics of humoral immunity between adults and children at the same dose, or children who received doses of 50 μg and 100 μg, and the immune response between these groups. I understood the difference more accurately. The team also analyzed whether mRNA vaccination of children evoked an immune response with a clear ability to recognize SARS-CoV-2VOC.

result

Studies show that 12 children were vaccinated with the Moderna vaccine at a dose of 100 μg, or adult, with a median of 9 years ranging from 7 to 11 years, and 42% of women were in line with the recommended adult dose. did. In addition, another 12 children received 50 μg, a pediatric dose of mRNA-1273, with a median age ranged between 6 and 11 years, with 50% being female. In addition, children in both cohorts were vaccinated on days 0 and 28, respectively.

The authors stated that doses of 50 μg and 100 μg of the Moderna vaccine are equally well tolerated. Fever, injection site pain, and malaise were typical mild vaccination-related side effects.

The Moderna mRNA vaccine was significantly immunogenic in children 6-11 years and elicited a better humoral response than was observed after viral exposure. Humoral features induced by the granular vaccine reveal differences in vaccine response between children and adults, with preferential induction of immunoglobulin G (IgG) response and IgM and IgM, which are significantly more functional in children compared to adults. It showed a decrease in IgA reaction. Children initiated a potent opsonic phagocytic activity and Fcγ receptor binding response at a dose of 100 μg comparable to that of adults. In addition, children responded more diversely, but comparablely, at 50% of adult doses compared to adults.

The team observed significant induction of immunity targeting most SARS-CoV-2 VOCs, with the exception of the Omicron mutant. Children vaccinated at a dose of 100 μg carried IgG with greater identification of the Omicron S protein compared to adults immunized at a dose of 100 μg and children vaccinated at a dose of 50 μg. However, the IgG and Fc receptor attachment profiles were very similar between children and adults. Children in the 50 μg dose group showed lower cross-VOC recognition, while children in the 100 μg dose group showed an immune response with enhanced cross-VOC width.

Conclusion

Overall, the findings show that children vaccinated with 100 μg of COVID-19 Moderna vaccine showed a 100% vaccine response rate prior to the second vaccination. On the other hand, the immune patterns of children vaccinated at low doses (50 μg) were similar to those of adults vaccinated with 100 μg (adult-recommended vaccine dose).

Moreover, children showed an IgG-dominant vaccine-induced immune response that was larger than adults at the equivalent 100 μg dose but less consistent at the 50 μg dose. Children have developed antibodies with improved Fc receptor attachment. titer..

In addition, children developed cross-VOC humoral immunity similar to adults, reducing attachment of the omicron-specific receptor-binding domain (RBD), but ensuring that attachment of the omicron S protein was maintained. In addition, the ability to bind to Fc receptors was maintained in a dose-dependent manner.

Overall, study data suggest that COVID-19 mRNA vaccination in children at doses of 50 and 100 μg results in a strong cross-VOC antibody response and highly retained omicron-specific functional humoral immunity. ing. Current findings indicate that the mRNA-1273 vaccine induces a robust but dose-dependent functional humoral pediatric immune response in children.