Plasma proteome confirmed the link between cellular and humoral immunity SARS-CoV-2.
The immune system, or acquired immune system, is a strategic immune response supplemented by specific antibodies. This response utilizes immunological memory to strengthen an immune response and is activated by exposure to pathogens. Although it tends to be slower than the native response, it is an important step in the process of eliminating pathogens.
With the ongoing COVID-19 epidemic, increased knowledge of variable immunity in children against the SARS-CoV-2 virus is of paramount importance in defining strategies possible vaccination and in reconsideration of control measures during the pandemic.
A recent study by researchers in Italy analyzed anti-SARS-CoV-2 antibodies as well as their neutral activity, along with a specific cell antigen response, to viral loads in nasopharyngeal swabs. The data were presented at the Conference on Retroviruses and Fair Diseases (CROI) 2021 meaningful sessions.
The study included 42 participants whose viral loads were measured by RT-PCR and digital droplet PCR tests on long-term samples of nasopharyngeal swabs at 7 days after symptom onset. A focus-shaped assay was used to test for virus infection and virus antibodies were examined with Diasorin and neutralization assays.
In addition, SARS-CoV-2 specific CD4, CD40L + T and Spike-specific B cells were analyzed by flow cytometry. 2 Olink panels were used to measure plasma proteomic profile. The Mann-Whitney, an experiment used to compare differences between two independent groups, was used to compare methods in individuals with or without neutral activity.
Results from the study showed that higher levels of viral loading were detected in seronegative patients expressed for both SARS-CoV-2 antibodies and neutral activity. Lower virus infection was also associated with higher SARS-CoV-2 antibodies and neutral activity.
Improvement of humoral response was associated with the presence of SARS-CoV-2-specific IgD-CD27 + B cells, with a higher frequency of seropositive-detected SARS-CoV-2 specific B cells compared with seronegative.
“This work assumes the virological and immunological characterization of SARS-CoV-2 infected children exhibiting Ab-mediated neutral mediated activity,” the authors wrote. “It shows that children with neutral antibodies show viral reduction, faster virus clearance and lower in vitro infection. These data provide information that can guide vaccine endpoints and quarantine measures policies. ”