Immune Responses after a Third Dose of mRNA Vaccine Differ in Virus-Naive versus SARS-CoV-2– Recovered Dialysis Patients
Philippe Attias, Imane Azzaoui, Khalil El Karoui, A. SELLE, Aurélien Sokal, Pascal Chappert, Philippe Grimbert, I. Fernández, Magali Bouvier‐Alias, Chloé Samson, Djamal Dahmane, Philippe Rieu, Patrice Nizard, Slim Fourati, Hamza Sakhi, Matthieu Mahévas
Abstract
Background and objectives After two doses of mRNA vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), patients on dialysis show a defective humoral response, but a third dose could increase anti–SARS-CoV-2 spike IgG titers. Responses could be different in virus-naive and SARS-CoV-2–recovered patients on dialysis. However, characterization of memory B cell response after three doses is lacking. Design, setting, participants, & measurements We evaluated the dynamics of antireceptor binding domain IgG titers and antireceptor binding domain memory B cells until 6 months after two and three doses (administered within 6 months after the second dose) of mRNA vaccine in SARS-CoV-2–recovered and virus-naive dialysis populations. Results were analyzed by ordinary one-way ANOVA, the Kruskal–Wallis test, or the Wilcoxon matched-pairs test as appropriate. Results In total, 108 individuals (59 patients on dialysis and 49 controls) were included. In virus-naive patients on dialysis, antireceptor binding domain IgG response was quantitatively lower after two doses compared with healthy controls, but IgG titers increased by three-fold after three doses ( P =0.008). In SARS-CoV-2–recovered patients on dialysis, antireceptor binding domain IgG titers after two doses were significantly higher compared with virus-naive patients on dialysis but did not significantly increase after a third dose. Regarding memory B cell response, we detected receptor binding domain–specific memory B cells at similar proportions in virus-naive patients on dialysis and vaccinated controls after two doses. Moreover, a strong receptor binding domain–specific memory B cell expansion was observed after the third dose in virus-naive patients on dialysis (5.5-fold; P <0.001). However, in SARS-CoV-2–recovered patients on dialysis, antireceptor binding domain memory B cells remained unchanged after the third dose. Conclusions The third dose of mRNA vaccine given within 6 months after the second dose boosts serologic and memory response in virus-naive patients but not in SARS-CoV-2–recovered patients on dialysis. Clinical Trial registry name and registration number: COVID-19: SARS-CoV-2 Specific Memory B and T-CD4+ Cells (MEMO-COV2), NCT04402892