Fig. 1.

Pneumococcal colonization in mice reduces subsequent S. aureus carriage in an antibody-dependent manner. Colonization density of S. aureus 502A in C57BL/6 wild-type (closed circles) or antibody-deficient μMT mice (open circles) 5 wk after prior colonization with S. pneumoniae TIGR4, S. pneumoniae P1121, or sham (PBS) colonization. 502A carriage levels were assessed in lavages of the upper respiratory tract at day 1 postchallenge. Horizontal solid lines indicate median values; dotted line indicates limit of detection, N.S., not significant.