Journal: The Journal of Biological Chemistry
Article Title: Molecular mechanisms of heparin-induced modulation of human interleukin 12 bioactivity
doi: 10.1074/jbc.RA118.006193
Figure Lengend Snippet: Modulatory activity depends on heparin chain length. Isothermograms describe binding interactions between heparin and hIL-12 (A) or mIL-12 (B). The upper panel of each isothermogram shows the raw data obtained for each of the 30 injections. The lower panels display the best fit data to one-set of sites binding model using OriginTM version 7.0 software. hIL-12 activity as measured by IFN-γ production by NK-92MI cells (C) or secreted alkaline phosphatase by HEK-BlueTM IL-12 cells (D) was measured after co-culture with heparin oligosaccharides or LMWH (10 μg/ml). Heparin octasaccharide, decasaccharide, dodecasaccharide, and LMWH significantly increased the bioactivity of IL-12 in NK-92MI cells and HEK-BlueTM IL-12 cells (***, p < 0.0001 versus hIL-12 alone via two-way ANOVA). Heparin tetrasaccharide did not increase the bioactivity of hIL-12 in NK-92MI cells (p > 0.05 versus hIL-12 alone via Tukey's post-test) and HEK-BlueTM IL-12 cells (p < 0.0001 versus hIL-12 alone via Tukey's post-test). Heparin hexasaccharide increased the bioactivity of hIL-12 in NK-92MI cells (p < 0.0001 versus hIL-12 alone, p < 0.01 versus hIL-12 plus LMWH via Tukey's post-test) and showed no effect on hIL-12 bioactivity in HEK-BlueTM IL-12 cells (p > 0.05 versus hIL-12 alone via Tukey's post-test). Columns represent mean ± S.D. of triplicate measurements. Experiments were performed in triplicate and repeated three times with similar results.
Article Snippet: Isothermograms were obtained using 30 injections and were best-fit to a one-site/multiple-site binding model using the Origin TM version 7.0 software supplied by Microcal.
Techniques: Activity Assay, Binding Assay, Software, Co-Culture Assay
