Detection of bomapin antigen in control and PMA- or TNF-α–treated THP-1 cells. THP-1 cells (10⁶ cells/mL, 25 mL/flask, 162 cm²/flask) were incubated in serum-containing media in the absence (lanes 1 and 2) or presence of either PMA (10⁻⁸ mol/L; lanes 3 and 4) or TNF-α (30 U/mL; lanes 5 and 6) as described above. After 72 hours, the cells were washed twice, homogenized, and centrifuged, and the cytosol preparations (1 mg) were incubated with either Sepharose-antibomapin (lanes 1, 3, and 5) or Sepharose-normal rabbit IgG (lanes 2, 4, and 6). The beads were washed and the material eluting with SDS-sample buffer was analyzed by immunoblotting using biotin-labeled affinity purified antibomapin, streptavidin-peroxidase, and the enhanced chemiluminescence detection system. Lane 7 contained 300 ng of GST-bomapin.