Immunohistochemistry of omega class glutathione S-transferase in human tissues

Omega class glutathione transferase (GSTO) has been recently described in a number of mammalian species. We used immunohistochemistry to determine the cellular and tissue distribution of GSTO1-1 in humans. Expression of GSTO1 -1 was abundant in a wide range of normal tissues, particularly liver, macr ophages, glial cells, and endocrine cells. We also found nuclear staining i n several types of cells, including glial cells, myoepithelial cells of the breast, neuroendocrine cells of colon, fetal myocytes, hepatocytes, biliar y epithelium, ductal epithelium of the pancreas, Hoffbauer cells of the pla centa, and follicular and C-cells of the thyroid. These observations and th e known activity of GSTO1-1 suggest biological functions that are not share d with other GSTs.