Inhibition of T-cell signaling of monocytes and THP-1 cells by HS.

(A) THP-1 cells were activated for 48 hours by fixed, stimulated T lymphocytes at a cellular ratio of 8 T lymphocytes/THP-1 cell in the presence of increasing doses of HS (closed circles), FCS (open circles), or cord blood serum (closed trianlges). (B) THP-1 cells were activated for 48 hours by either fixed, stimulated HUT-78 cells (fsHUT-78) at a cellular ratio of 8 HUT-78 cells/THP-1 cell (closed symbols) or 10 μg/mL LPS and 5 ng/mL PMA (open symbols) in the presence of increasing doses of HS. THP-1 cells (C,D) and monocytes (E,F) were activated for 48 hours by increasing doses of membranes isolated from stimulated HUT-78 cells in the presence (closed squares) or absence of 10% HS (closed circles). TNF-α (C,E) and IL-1β (D,F) were measured in culture supernatants. Results represent mean ± SD, n = 3 except in panel B where n = 7. In panels A and B, 100% represents the production of IL-1β after 48 hours of culture in the absence of inhibitor.