Fig. 1

Anti-Panton-Valentine-leukocidin (PVL)-antibodies in Africans compared to Germans. Serum levels of anti-PVL-antibodies (a) and anti-Hla-antibodies (b) of participants from Germany and Africa were quantified by ELISA and expressed in arbitrary units (AU). Median values for levels of antibodies to PVL in Caucasians and Africans were 0.7 AU (interquartile range (IQR), 0.5–1.1 AU) and 1.9 AU (IQR, 1.4–2 AU), respectively. Median values for levels of antibodies to Hla in Caucasians and Africans were 29.1 AU (IQR, 20.1–40.2 AU) and 42.4 AU (IQR, 30.8–50 AU), respectively. c The titers of antibodies against PVL were corrected for their respective anti-Hla titers and displayed as fold-change to median serum level of Caucasians (IQR, 0.7–1.4). Median value for relative anti-PVL titers in Africans was 1.6 (IQR, 1.2–2). Statistical significance was analyzed by Mann-Whitney test or unpaired t test (** p < 0.01, *** p < 0.001, **** p < 0.0001)