Inage H

Studies on platelet function in patients with prostatic cancer: Preliminary report

Platelet function was evaluated as an index of the thromboembolic tendency in patients with untreated, advanced prostatic cancer. Patients with benign prostatic hypertrophy (BPH) and similar age distribution served as a comparison group. Platelet aggregations were elevated in both groups, but not significantly different from each other. Platelet serotonin level in patients with prostatic cancer was lower than in patients with BPH (p less than 0.01), whereas plasma serotonin level in patients with prostatic cancer (within normal ranges in our series) was lower than in patients with BPH (p less than 0.001). Levels of 2 intraplatelet proteins, beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) in the two groups of patients were similar. However, levels of beta-TG were elevated significantly in both groups of patients compared with those of healthy individuals. These studies revealed that the platelet serotonin levels in advanced prostatic cancer patients differed significantly from those in patients with BPH. The platelet serotonin level thus may provide an index of platelet activation in patients with prostatic cancer.

Circulating Immune Complexes and Immunosuppressive Acidic Protein in Patients with Renal Cell Carcinoma

Sera from 23 patients with renal cell carcinoma were tested for circulating immune complexes by Clq binding assay and immunosuppressive acidic protein by single radial immunodiffusion. The mean values of circulating immune complexes and immunosuppressive acidic protein in the patients were significantly higher than those of normal controls, and over-all positive rates were 52 and 35 per cent, respectively. There was a significant correlation between immunosuppressive acidic protein levels and the extent of tumor invasion. Immunosuppressive acidic protein may be a more useful marker than circulating immune complexes. However, presently synthetic evaluations of patients with various nonspecific markers, including these 2 factors, will be necessary.

Abnormal expression of complement receptor (CR1) in IgA nephritis: increase in erythrocytes and loss on glomeruli in patients with impaired renal function.

The number of complement receptor for C3b (CR1) molecules in erythrocytes from patients with renal diseases was measured by an immunoradiometric assay using monoclonal antibodies against CR1. IgA nephritis patients with high serum creatinine value (Scr) showed markedly elevated levels of CR1, whereas patients with normal Scr had normal CR1 levels. A similar increase in CR1 number was observed in membranoproliferative glomerular nephritis with high Scr. CR1 of these patients functioned normally as a cofactor of C3b inactivator in cleaving immune complex-bound C3b. In contrast, a high frequency (5/6) of negative staining of glomerular CR1 was observed in IgA nephritis patients with high Scr by immunofluorescence study. We postulate that the disease-associated, acquired factors at least in part contribute to the abnormal expression of CR1: elevated levels in erythrocytes and defective expression on glomeruli.