Fig. 1

Cytochemical staining for GGT enzyme activity expressed in activated monocytes. Monocytes from the blood of healthy donors expressing different levels of GGT activity. The azo-dye reaction product (reddish-brown) varies in intensity from slight to very strong, resulting in diffuse staining or granular positivity. Nuclei were counterstained with methyl green. Original magnification: ×100 (a). Monocytes isolated from fresh buffy coats were incubated in the presence of TNFα/IL-1β (both 10 ng/ml; 24 h) or LPS (5 μg/ml; 24 h). GGT activity was measured in the 10,000×g centrifuged supernatants (b, c) and in cellular homogenates (d, e). Results—expressed as mU/mg of cellular proteins—are mean ± SD of five to nine separate determinations. Data were analyzed by Student’s t test for paired data; *p < 0.05 as compared with the corresponding control