Effect of postgrafting administration of G-CSF on production of IL-12 by DCs in HLA-mismatched recipients of hematopoietic transplants.

Expression of the gene for the inducible IL-12p40 subunit and production of the bioactive IL-12p70 protein were determined in DCs from G-CSF–treated patients (G-CSF+, panel A) and patients not given G-CSF (G-CSF−, panel B). In patients who received G-CSF postgrafting, DCs expressing the IL-12p40 gene were first detected 14 to 22 months after transplantation, whereas they were first detected 1 to 3 months in patients not given G-CSF (RT-PCR results, left side of each panel). Patients were chosen randomly for this analysis at the time of transplantation, and data are representative of more extensive analyses in patients in both series. ELISA analyses (right side of each panel) confirmed that IL-12p40 gene expression (mRNA+) correlated with actual production of bioactive IL-12 in each treatment protocol, ie, in G-CSF–treated patients (G-CSF+, panel A) and patients not given G-CSF (G-CSF−, panel B). The ELISA results are mean ± SE values for IL-12 production by IL-12p40 mRNA+ samples in the 2 series.