FIG 6.

Clearance of experimentally inoculated nasal S. aureus associates with augmented innate nasal mucosal defense. Six macaques participated in four S. aureus decolonization/experimental S. aureus recolonization protocols and had their noses sampled as described in Materials and Methods. Based on nasal swab testing results that indicated each nostril's S. aureus carriage pattern, either left or right nostril secretions (the same for all macaques in each experiment) were assessed for cytokines using a Luminex assay. The levels of IL-1β (A) and IL-1RA (B), the IL-1RA/Il-1β ratio (C), and the levels of IL-8 (D) and MCP-1 (E) in nasal secretions are shown for each nostril that transitioned from S. aureus negativity (SA-neg) to S. aureus positivity (SA-pos) either upon experimental inoculation or after testing negative for S. aureus and then positive again during the follow-up period. Cytokine data were further stratified according to whether the nostrils eventually cleared inoculated S. aureus (Clearance) or stayed colonized with inoculated S. aureus (Carriage). Error bars represent the mean and SEM. Dotted horizontal lines indicate the limit of detection.