Figure 1.

NAb and T cell responses after a fourth vaccine dose and breakthrough infections

(A) NAbTs against Omicron BA.1, WT, and Delta were measured after the fourth vaccine dose. NAbT below (IC₅₀ titer <40) or above the quantitative range (IC₅₀ titer >2,560) are indicated by horizontal lines.

(B) NAbTs against Omicron BA.1, BA.2, WT, or Delta after four vaccine doses.

(C and D) Levels of (C) CD4⁺CD137⁺OX40⁺ or (D) CD8⁺CD137⁺CD69⁺ T cells in patients stimulated with WT or Omicron BA.1 full-length spike peptide pools after three or four vaccine doses.

(E) NAbTs against Omicron BA.1, BA.2, WT, and Delta before and after breakthrough infection. Infections after two or three vaccine doses are displayed separately. Timing of blood sampling in relation to vaccination and infection is color-coded. The regression line and 95% CI were fitted using LOESS regression.

(F and G) Comparison of NAbTs against Omicron BA.1, BA.2, WT, and Delta before infection (but after last vaccine dose) and after infection in patients with breakthrough infection after (F) two and (G) three vaccine doses. Violin plots denote the density of data, point-range denotes the median and the 25^th and 75^th percentiles. Patients are indicated as individual data points, and samples from individual patients are connected. The proportions of patients with detectable titers are visualized with pie charts (dark blue denotes patients with IC₅₀ titers >40). Biological replicates are patient subjects. There were no technical replicates.