In vitro differentiation and antigenic changes in human melanoma cell lines.

Malignant transformation of melanocytes may be associated with changes in the expression of HLA antigens and melanoma-associated antigens (MAA). To determine whether these changes reflect the differential expression of HLA antigens and MAA by melanocytes at different stages of differentiation, we have studied the effect of the reversible induction of differentiation by fibroblast interferon (interferon beta) and/or 12-O-tetradecanoyl-phorbol 13-acetate (TPA) on the expression of HLA antigens and MAA by the melanoma cell lines DU-2, FO-1 and HO-1. The three melanoma cell lines differed in their sensitivity to the differentiating and antiproliferative activity of these two compounds and displayed an increased growth suppression and induction of differentiation, when incubated with the combination of TPA and interferon beta.

Enhanced in vitro growth suppression of human glioblastoma cultures treated with the combination of recombinant fibroblast and immune interferons.

In the present study we have evaluated the effect of recombinant human fibroblast, IFN-beta ser, and immune, IFN-gamma, interferon, alone and in combination, on the proliferation of fifteen early passage human glioblastoma cell cultures. Explant cultures were established from glioblastoma tumor tissue obtained at the time of surgery. After sufficient outgrowth, cultures were dispersed with trypsin/versene and maintained as independent cell lines.

Immunohistochemical localization of procainamide in normal, ischemic, and necrotic canine myocardium during acute experimental myocardial infarction.

This report represents the first application of immunohistochemical methods for localizing an exogenously administered drug. Intravenously administered procainamide was localized in normal, ischemic, and necrotic myocardium in 23 dogs. Rabbit antiprocainamide antibodies were used in an avidin-biotin-peroxidase complex staining method.

Effect of recombinant human fibroblast interferon and mezerein on growth, differentiation, immune interferon binding and tumor associated antigen expression in human melanoma cells.

The combination of recombinant human fibroblast interferon (INF-delta) and the antileukemic compound mezerein (MEZ) results in a synergistic suppression in the growth of human melanoma cells and a concomitant increase in melanin synthesis. In the present study we have further analyzed this synergistic interaction and have also evaluated the effect of IFN-delta and MEZ, alone and in combination, on recombinant human gamma interferon (IFN-gamma) binding and Class I HLA and melanoma associated antigen (MAA) expression in the HO-1 human melanoma cell line. Single cell clones isolated from the HO-1 cell line varied in their sensitivity to the antiproliferative effects of IFN-delta and MEZ.

Distribution of fibrinogen and albumin in normal, ischaemic, and necrotic myocardium during the evolution of myocardial infarction: an immunohistochemical study.

The role of mediators of inflammation in the pathogenesis and evolution of myocardial infarction has attracted increased interest as interventions which inhibit the inflammatory response after coronary artery occlusion have been shown to decrease infarct size. The distribution of fibrinogen and albumin in ischaemia myocardium after closed chest balloon occlusion of the left anterior descending coronary artery was studied by immunohistochemical techniques in 34 dogs, and compared to morphological evaluation of cellular injury. In myocardium which was ischaemic but not necrotic (that is, glycogen loss and the absence of light and electron microscopic and tetrazolium staining evidence of necrosis, n = 8 dogs) no accumulation of these proteins was detected within the ischaemic zone.