Histamine release and MCP mRNA expression profiles. (A) Cells harvested from 5-week-old HF cultures were examined for histamine release (means ± SDs from triplicate samples) after stimulation with the indicated agents. Some samples were pulsed with DNP-specific IgE and then stimulated with DNP-conjugated HSA or HSA alone. (B) Cells harvested from different HF cultures (5-week-old) were fractionated into CD45⁺ and CD45^– populations by FACS and then examined for histamine release. Statistically significant differences are indicated with asterisks (**P < .01). (B) Cells harvested from 5-week-old HF cultures were purified for CD45⁺ populations by magnetic beads and examined for mRNA expression profiles for the indicated MCP. Pam 212 keratinocytes were analyzed in parallel to serve as a negative control. Data shown are PCR products after 30 cycles of amplification visualized by ethidium bromide staining. Results shown in this figure are representative of 2 independent experiments.