Circulating intercellular adhesion molecule-1 in melanoma patients: induction by interleukin-2 therapy.

Intercellular adhesion molecule-1 (ICAM-1, CD54), a molecule bound to the cell surface membrane, mediates various cell-cell interactions in inflammation and immunosurveillance. By means of a new specific enzyme-linked immunosorbent assay (ELISA) for soluble ICAM-1, free circulating ICAM-1 was measured in serum from five healthy volunteers, 10 melanoma patients at different stages of their disease, and eight patients receiving high-dose interleukin-2 (IL-2) for metastatic melanoma. No correlation between the concentration of circulating ICAM-1 and the tumor burden could be detected. In melanoma patients receiving high-dose IL-2, we observed an increase of circulating ICAM-1 of up to 200%, compared to the concentration prior to therapy, ranging between 4 and 13 ng/ml. The increase in circulating ICAM-1 was associated with the induction of tumor necrosis factor-alpha and interferon-gamma.