Antibody response 6 months after the booster dose of Pfizer in previous recipients of CoronaVac

• Published in: Journal of medical virology Vol. 95; no. 1; pp. e28169 - n/a
• Main Authors: Silva, Maria Francilene Souza, Pinto, Ana Carolina Matias Dinelly, Oliveira, Fátima de Cássia Evangelista, Caetano, Ludmilla Freire, Araújo, Fernanda Montenegro de Carvalho, Fonseca, Marcela Helena Gambim
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.01.2023; John Wiley and Sons Inc
• Subjects: Antibodies; Antibodies, Viral; Antibody Formation; Antibody response; BNT162 Vaccine; BNT162B2 vaccine; booster dose; CoronaVac; Coronaviruses; COVID-19 - prevention & control; COVID-19 vaccines; COVID‐19 vaccine; Humans; Immune response (humoral); Immunoglobulin G; Immunoglobulin M; Infections; mRNA; Nucleocapsids; Polymerase chain reaction; Proteins; Respiratory diseases; SARS-CoV-2 - genetics; SARS‐CoV‐2; Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Short Communication; Short Communications; Spike protein; Vaccines; Viral diseases; Virology; Viruses; COVID-19 vaccine; SARS-CoV-2; antibodies; CoronaVac; booster dose; BNT162B2 vaccine
• ISSN: 0146-6615; 1096-9071
• DOI: 10.1002/jmv.28169

The most widely used vaccines were messenger RNA (mRNA), viral vector, and inactivated virus with two‐dose schedules. In Brazil, the CoronaVac (Sinovac) was the first vaccine approved for emergency use, and the third dose was administered, preferably, with the BNT162b2 vaccine. We evaluated antibody levels after 6 months of the booster dose with BNT162B2 in previous recipients of CoronaVac and whether a subsequent severe acute respiratory syndrome coronavirus 2 (SARS‐COV‐2) infection enhances the antibody response. We analyze the humoral response (spike [S] IgM for the SARS‐CoV‐2 and IgG for the S and nucleocapsid [N] proteins) in samples collected before the third dose and 6 months after the third dose. The presence of antibodies was measured by using Abbott Architect i2000SR. The IgM and IgG antispikes were stimulated mainly 30 days after the third dose (30d/3D), with a decline over time. The IgG anti‐N was stimulated predominantly in 90d/3D and 180d/3D. The N IgG levels were 50 and 35 times higher in the positive polymerase chain reaction (PCR) group in 90d/3D and 180d/3D, respectively. The S IgG titers were 1.5 times elevated in the positive PCR group, in 180d/3D. The BNT162b2 boosted the S IgG levels, decreasing after 60 days. The booster shot induced IgM and IgG antibodies against spike protein. Infection after vaccination increased antibodies against protein N.