Study of humoral and cellular immunity in vaccinated with mRNA-1273 Gutiérrez Bautista, Juan Francisco López Nevot, Miguel Ángel Gómez Vicente, Esther Quesada, Trinidad Marín, Eva María Rodríguez, Ana Rodríguez, Ana Isabel Rodríguez Granger, Javier Cobo, Fernando Sampedro, Antonio Moderna vaccine Humoral response SARS-CoV-2 mRNA vaccines mRNA-1273 vaccine This work was supported by "Investigacion y Desarrollo (I + D) del Sistema Andaluz de Salud (SAS)" and Instituto de Salud Carlos III (Proyecto FIS PI21/01708). The new vaccines against SARS-CoV-2 have raised a lot of expectations about their ability to induce immunity and the duration of this. This is the case of mRNA vaccines such as Moderna’s mRNA-1273. Therefore, it is necessary to study the humoral and cellular immunity generated by these vaccines. Our objectives are determining what is the normal response of antibody production, and what is the level of protective antibodies and monitoring patients in case of subsequent infection with COVID-19. We present the first results of a longitudinal study of the humoral response in 601 health workers vaccinated with Moderna. The results show a humoral immunity at 90 days after the second dose of 100%, with a strong decrease between the levels of circulating anti-S IgG antibodies between days 30 and 90 postvaccination. Observing a steeper decline in those who had higher titles at the beginning. In addition, we present a cellular response of 86% at three months after the second dose, which is related to low humoral response. 2022-03-29T11:52:03Z 2022-03-29T11:52:03Z 2022-02-23 journal article Gutiérrez-Bautista, JF... [et al.]. Study of humoral and cellular immunity in vaccinated with mRNA-1273. APMIS. 2022; 00: 1– 9. DOI [10.1111/apm.13215] http://hdl.handle.net/10481/73916 10.1111/apm.13215 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ open access Atribución-NoComercial-SinDerivadas 3.0 España John Wiley & Sons