Three children with Wilms' tumors have been shown to contain an abnormal mucin, or protein‐polysaccharide complex, in their serum, urine, and in cell‐free tumor extracts. This material appears to be a complex polymer of hexosamine and uronic acid with protein, and has an unusually low isoelectric point. Detection of the protein‐polysaccharide complex in the blood is correlated with the clinical stage of growth of the Wilms' tumor and the appearance of recurrent metastases. During those periods of time when the children were clinically free of disease, no abnormal protein‐polysaccharide complex could be identified in serum or urine samples. However, when the tumor recurred, this material increased in concentration and became maximal during terminal stages of the disease. Detecting the presence of this material has been shown to be particularly useful in improving diagnosis and long‐term care of these children with Wilms' tumor. Studies in our own laboratories and elsewhere suggest strongly that this material is a secretion product of the tumor itself. The finding of a tumor‐derived protein‐polysaccharide complex in patients with Wilms' tumor adds this disorder to the growing list of functioning secretory malignant tumors.
Dispersion of confluent monolayers of BHK21 cells with ethylenediaminetetraacetate yields a material that inhibits cell proliferation, whereas identical extraction of polyoma-virus-transformed cells provides material which enhances cellular proliferation. The material was partially characterized.
Various sources and components of mammalian sera were evaluated for their ability to maintain or inhibit sperm motility. Human, rabbit, hamster, and porcine sera were equal in ability to maintain motility of human sperm. Four sources of fetal calf serum and one source of neonatal calf serum were unable to maintain motility of human sperm or sperm-fertilizing potential. In the presence of human serum, fetal calf serum actually inhibited human sperm motility. Fetuin, a component of fetal calf serum, contained the inhibitory activity. An inhibitory effect of fetuin on porcine and caprine sperm motility was also observed. The inhibitory activity resided in the second peak when fetuin was separated by isoelectric focusing. The sperm head membranes remained impermeable to dye, and mitochondrial membrane potential was maintained after motility had been reduced to almost zero by incubation with fetuin and fetuin fractions. Fetuin or the active portion of the molecule may be a useful component of a vaginal contraceptive and in research where inhibition of motility is desirable.
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