EVALUATION OF THE HUMORAL RESPONSE TO THE THIRD DOSE OF SARS-COV-2 VACCINES IN LIVER TRANSPLANT PATIENTS

DUCASA, NICOLÁS; BENENCIO, PAULA; ANDERS, MARGARITA; BARBERO, MANUEL; MARIA FLORENCIA QUIROGA; BERINI, CAROLINA; ETCHEVES, PATRICIA; SCARTON, GIAMPAOLO; MAURO, EZEQUIEL; MENDIZABAL, MANUEL; BIGLIONE, MIRNA

Buenos Aires

Congreso; REUNIÓN CONJUNTA SAIC SAI&FAIC SAFIS 2022; 2022

SAIC SAI&FAIC SAFIS

Liver transplant recipients (LTR) mount lower humoral responsesto two doses of SARS-CoV-2 vaccines when compared to immunocompetent individuals (IC). We have previously evaluated thehumoral response in LTR who received two doses of vaccinesagainst SARS-CoV-2, and reported that 38% (46/120) of LTR donot produce anti-Spike antibodies, and that the heterologous regime rAd26/mRNA-1273 elicited a higher humoral response in LTRthan ChAdOx-1, rAd26/rAd5 and BBIBP-CorV homologous regimes(Mendizabal M, et al, 2022, Hepat. Commun.). Thus, we set out toevaluate the humoral response after three doses of SARS-CoV-2vaccines. Blood samples were extracted between 21 and 90 daysafter the third dose, from 81 RTH and 28 IC. Positive serology for anti-Spike (S1&S2) IgG antibodies and neutralizing antibody efficiencyagainst ACE2/RBD binding were evaluated by ELISA. In addition,we evaluated the humoral response of LTR and IC that had acquiredSARS-COV-2 infection after receiving the third dose. SARS-CoV-2infection was confirmed by anti-N IgG ELISA. We found that 18%(12/68) of LTR were negative for anti-Spike IgG, while all of the ICmounted a measurable response. LTR who responded to the thirddose showed significantly lower anti-Spike IgG levels compared toIC (p