Figure 1.

Humoral immune responses and specific B cell immunity after third vaccination in KTR. Humoral vaccine-specific immune responses were assessed by ELISA for anti–spike protein S1 IgG (A), spike protein S1 IgA (B), and virus neutralization by a blocking ELISA (C) at the indicated timepoints in KTR after administration of a third dose of either ChAdOx1 (n=11, black filled dots) or BNT162b2 (n=14, back empty dots). Thresholds defining a positive response are indicated by dotted lines. Relative frequencies (left) and absolute counts (right) of RBD-specific CD19⁺ B cells in all patients (D) and in responders IgG⁺ and nonresponders IgG- 7±2 days after second or third vaccination with ChAdOx1 or BNT162b2. (A–C) Kruskal–Wallis with Dunn’s post-test. The infected individual is depicted in red. (D, E) Mann–Whitney test.