Fig. 6. Selective neutralization of HylA improves acne lesions and mitigates inflammation.

a, b CD1 mice (n = 10) immunized with either Alum (Mock) or Alum-rHylA (HylA) were challenged i.d. with HL043PA1. Disease score (a) and IL-1b in skin homogenate at d2 post-challenge. c–e mice (n = 15) were immunized intraperitoneally (i.p.) with alum plus C-terminus of tetanus protein (TT) or multiple HylA epitopes linked to TT (mEHylA), then challenged i.d. with HL043PA1 C. acnes strain. Disease score (c) bacterial burden (d), and IL-1b (e) at d2 post-challenge. f serum (1:100,000 diluted) anti-HylA or anti-HylB IgG antibody titers after the third immunization with mEHylA vaccine. g, modeling of the HylA-i932 peptide complex. The i932 peptide docked in the HylA (PDB: 8FYG) active site cleft. The peptide is represented as yellow cartoon with the side chains shown by sticks. h, microscale thermophoresis (MST) analysis of HylA binding to peptide i932. MST dose response curve obtained by titrating the i932 peptide (50 μM to 1.5 nM) against 30 nM fluorescent labeled HylA. i–k, inhibitors (i932, i933, or i93) at 10 µg and HL043PA1 strain (2 × 10⁷CFU/mouse) were co-injected i.d. into CD1 mice (n = 19 for vehicle and i932, n = 9 for i933 and n = 10 for i93). Disease score (i), CFU (j), and skin IL-1b (k) d1 (24 hr) post-infection. Bars denote median. Data are from two (a, b, f, i–k) or three (c–e) independent experiments with each data point representing one mouse. Data in h is represented as mean $\pm$SD of triplicates of one independent experiment and the experiment was repeated three times. The data in a–e were analyzed by non-parametric two-tailed Mann-Whitney U test, and in f, i–k by non-parametric Kruskal-Wallis one-way ANOVA test. Source data are provided as a Source Data file.