The cytokines and chemokines that are induced in normal MNCs with exogenous PlGF are also elevated in SCD MNCs at baseline. (A) RNase protection assay was performed using RNA from normal peripheral blood MNCs (A1-A4, lanes 2-5) and those derived from subjects with SCD at steady state (S1-S8, lanes 6-13). HeLa cell RNA was used as a control RNA. (B) Mean densitometry of MCP-1, VEGF, IL1-β, and IL-8 shown in panel A in normal controls (□) and in SCD patients (▪). Error bars represent SEM.