Secreted antigens of Mycoplasma hominis. M. hominis cells from a mid-logarithmic phase culture were incubated for 1 h at 37°C in PBS containing 0 to 5 mM CaCl2 as indicated. Proteins in 0.4 ml of culture supernatants and cell pellets from 0.02 ml of cultures were separated in 9.5 % polyacylamide gels and silver stained (A.) or Western blotted (B.) using the monoclonal antibodies BG11 (OppA), LF8 (P80) and CG4 (P60), AH10 (P55), BG2 (P50) or KD2 (EF-Tu). The predominant band in the supernatant without calcium ions is recognized by the anti-P80 antibody LF8. Molecular Weight Marker: See Blue Plus 2 (Invitrogen, Karlsruhe, Germany).