Host response to Staphylococcus aureus cytotoxins in children with cystic fibrosis  Ashley D. Chadha, Isaac P. Thomsen, Natalia Jimenez-Truque, Nicole R. Soper, Lauren S. Jones, Andrew G. Sokolow, Victor J. Torres, C. Buddy Creech  Journal of Cystic Fibrosis  Volume 15, Issue 5, Pages 597-604 (September 2016) DOI: 10.1016/j.jcf.2015.12.023 Copyright © 2016 European Cystic Fibrosis Society. Terms and Conditions

Fig. 1 Study overview. Children within the target age range with approached in the Vanderbilt Cystic Fibrosis Clinic and invited to participate in the study. Subjects were recruited until 50 subjects were enrolled, a sample size calculated based on our previous studies of serologic responses to target antigens. Journal of Cystic Fibrosis 2016 15, 597-604DOI: (10.1016/j.jcf.2015.12.023) Copyright © 2016 European Cystic Fibrosis Society. Terms and Conditions

Fig. 2 Geometric mean IgG titers in serum from children with cystic fibrosis. For those subjects that experienced pulmonary exacerbation during the study period, titers are measured during exacerbation and at follow-up (1–3months). For LukA, alpha toxin and LukS-PV, geometric mean titers (GMT) were significantly higher if S. aureus was detected at the time of exacerbation (p<0.01 for each comparison; Mann–Whitney U test). For LukA only, GMTs were significantly higher at exacerbation follow-up compared to titers during the exacerbation (p<0.05, Wilcoxon signed-rank test). Journal of Cystic Fibrosis 2016 15, 597-604DOI: (10.1016/j.jcf.2015.12.023) Copyright © 2016 European Cystic Fibrosis Society. Terms and Conditions

Fig. 3 Predictive capacity of LukAB serology in relation to detection of S. aureus during pulmonary exacerbation. Number of samples for each given titer range are displayed. A line is arbitrarily drawn at a titer of 1:160 to demonstrate a potential cut-off value for possible predictive capacity of a positive titer. In this dataset, the presence of a positive S. aureus culture during a pulmonary exacerbation resulted in a 34-fold increase in odds of having a LukA titer ≥1:160. Journal of Cystic Fibrosis 2016 15, 597-604DOI: (10.1016/j.jcf.2015.12.023) Copyright © 2016 European Cystic Fibrosis Society. Terms and Conditions

Fig. 4 Neutralization of LukAB-mediated PMN-HL60 cytotoxicity in the presence of children with cystic fibrosis or healthy controls. Sera obtained during exacerbations when S. aureus was isolated were significantly more potent than those in which S. aureus was not isolated (P<0.01, independent t-test) or healthy control sera (P<0.001, independent t-test) as measured by geometric mean neutralization titer. Neutralizing capacity did not significantly differ during and post-exacerbation. Journal of Cystic Fibrosis 2016 15, 597-604DOI: (10.1016/j.jcf.2015.12.023) Copyright © 2016 European Cystic Fibrosis Society. Terms and Conditions