FIG. 4.

Secretory levels of TIMP-1 produced by MDMs. Freshly elutriated monocytes were cultured as adherent monolayers. At days 1, 3, and 7, cells were stimulated with 2 μg of CD40L per ml for 72 h, and TIMP-1 levels in the culture supernatant were analyzed by ELISA. Each sample was analyzed in triplicate. Levels of TIMP-1 were upregulated 3.4-fold from day 1 to day 7 (∗, P < 0.001). In addition, CD40L stimulation led to a statistically significant increase in TIMP-1 levels in cells stimulated on day 7 of culture (∗∗, P < 0.001). Representative data obtained from a total of three donors are shown. Values represent the mean of triplicate determinations ± standard error. Statistical analysis was performed with GraphPad Prism 2.0, using one-way ANOVA with Newman-Keuls posttest.