Time-dependent expression and release of MCP-1 in HMC-1 cells. HMC-1 cells (1 × 106 per mL) were cultured for various time periods in the presence of control medium (▴), rhSCF (100 ng/mL) (•), or a mixture of rhSCF (100 ng/mL) and PMA (50 ng/mL) (▪). After culture, cells were harvested, and MCP-1 peptide measured in supernatants (A) and cell lysates (B) by an ELISA. An accumulation of MCP-1 in the supernatants of either untreated or SCF-treated HMC-1 cells was seen. However, stimulation of cells with rhSCF or rhSCF + PMA significantly increased MCP-1 peptide release above control over time (A). The SCF-induced increase in MCP-1 expression in cell lysates (B) indicates induction of peptide synthesis. The results represent the mean ± standard deviation (SD) of triplicate cultures from one typical experiment. Similar data were obtained in two other experiments.
