Relationship between cytokine production and mRNA expression.

2.5 × 10⁶ cells were isolated and cultured in the absence or presence of 0.4 μg/mL concanavalin A (ConA). Cytokine concentrations (mean ± SE of triplicate cultures) in the culture supernatant and mRNA expression in the culture cells were measured using ELISA or real-time PCR assays, respectively. IL-10 mRNA expression after 3 or 12 hours of cultures in the absence of stimulus was assessed in PBMCs isolated from a patient with autologous GVHD and from 3 control individuals (A). Although IL-10 mRNA expression by PBMCs from the patient with autologous GVHD increased and correlated with IL-10 production (●–●), significant IL-10 production was not detected in 3 control individuals. IFN-γ concentrations and mRNA expression after 3, 12, or 24 hours of cultures in the presence of ConA were measured in CD4⁺ and CD8⁺ cells from a control individual (B). IL-10 protein production and mRNA expression levels were assessed in PBMCs from control individuals and from patients with autologous GVHD in the presence of ConA (C, n = 19). IFN-γ protein production and mRNA expression levels were assessed in PBMCs from control individuals or from patients with autologous GVHD in the presence of ConA (D, n = 20).