Immune maturation of anti-SARS-CoV-2 equine hyperimmune sera with application to biotherapeutics production

GONZÁLEZ VIACAVA, BELÉN; VARESE, AUGUSTO; MAZZITELLI, IGNACIO; LANARI, LAURA; AVILA, LUCÍA; GARCIA VAMPA, MARÍA J.; GEFFNER, JORGE; CASCONE, OSVALDO; DOKMETJIAN, JOSÉ C.; DE ROODT, ADOLFO; FINGERMANN, MATÍAS

IMMUNOLOGICAL INVESTIGATIONS

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 2021

0882-0139

Mass-vaccination against COVID-19 is still a distant goal for most low-to-middle income countries. The experience gained through decades producing polyclonal immunotherapeutics (such as an-tivenoms) in many of those countries is being redirected to develop similar products able to neutralize SARS-CoV-2 infection. In this study we analyzed the biological activity (viral neu-tralization or NtAb) and immunochemical properties of hyperimmune horses? sera (HHS) ob-tained during initial immunization (I) and posterior re-immunization (R) cycles using the RBD domain of the SARS-CoV-2 spike protein as antigen. HHS at the end of the R cycle showed higher NtAb titers when compared to those after the I cycle (35,585 vs. 7000 mean NtAb, respectively). Moreover, this increase paralleled an increase in avidity (95.2% to 65.2% mean avidity units, re-spectively). The results presented herein are relevant for manufacturers of these therapeutic tools against COVID-19.