Serum from the blood of people vaccinated with Sputnik V, like that of those who had coronavirus in 2020, contains neutralizing antibodies against the variants Gamma that originated in Manaos, Alpha first detected in UK Y Lambda (Andina), which have community circulation in the Argentinaaccording to a recent study by local scientists.

The work was carried out by researchers from the PAIS project (Argentine Interinstitutional Project of Genomics of SARS-CoV-2), the Biobank of Infectious Diseases BBEI, the Inbris Institute and the Hospital de Clínicas José de San Martín.

The objective was to evaluate “the neutralizing capacity of sera obtained from individuals infected by SARS-CoV-2 during the year 2020 and of individuals vaccinated with Sputnik V, compared to the variants of SARS-CoV-2 currently circulating in Argentina: lineages P.1 (Gamma, Manaos), B.1.1.7 (Alpha, UK) y C.37 (Lambda, Andina)”.

To make the comparison, the researchers took as a reference “the neutralizing activity exerted by the sera against the B.1 lineage (reference strain of the year 2020)”.

“What was observed is that both with one dose and with two the sera of people immunized with Sputnik V maintained the level of neutralizing antibodies against Alpha Y Lambda same as against the 2020 reference strain; the same thing happened with convalescent sera “, explained the virologist and member of the Country Project Humberto Debat.

The Sputnik V vaccine was the first to be applied in the country.

In the case of Gamma variant, the researcher detailed that “neutralizing antibodies decrease three times in relation to the response against the reference strain that was used in 2020, which, although significant, is not dramatic.”

The specialist recalled that “these in vitro tests only reflect the humoral response (antibodies) but not the cellular one (mediated by the lymphocytes that provide memory), so they do not express the total response of the immune system and a decrease in antibodies do not necessarily imply a decrease in protection. “

The data obtained by this work in relation to the decrease in the neutralization capacity of the sera of convalescent and vaccinated with Sputnik V versus variant Gamma are consistent with other studies conducted abroad with Pfizer vaccines and Oxford/Aztrazeneca.

One of the most important contributions of this study is that it reports for the first time that the variant Lambda (incorporated by the WHO as a variant of interest) is “efficiently neutralized by the antibodies generated in response both to infection by circulating variants in our country in 2020, as well as by those generated in response to vaccination with Sputnik V.”

The report recalled that since March of this year “a change in the circulation dynamics of viral variants of SARS-CoV-2 in Argentina it has raised a new alarm in the field of public health. “