Abstract: The present invention relates to a glucose-rich, mannose-containing oligosaccharide described herein has a molecular weight of approximately 1,000-5,000 daltons and is separated from interfering aloe components. The oligosaccharide inhibits loss of skin immunocompetency which is induced by ultraviolet irradiation. The oligosaccharide is obtained by cellulase cleavage of a precursor block polysaccharide of Aloe (FIG. 1) and has about 75% glucose, about 25% mannose and trace galactose. The precursor polysaccharide has a molecular weight of >2,000,000 daltons, is about 73% hexose with a total hexose to reducing sugar ratio of about 23:1. This polysaccharide is about 7% glucose, about 85% mannose and about 4% galactose. Also described is a method for obtaining an immunoprotective oligosaccharide by treating an Aloe extract with cellulase at a concentration of less than about 2 grams per 215 liters.

Abstract: Schistosoma mansoni eggs are ground to liberate soluble egg antigens which are fractionated and purified by absorption, gel filtration and/or ion exchange chromatography, and then radioactively labelled with .sup.125 I. A fraction, identified as MSA.sub.1, is specific to the mature egg stage of Schistosoma mansoni and thus can be used to detect the presence of antibody to mature Schistosoma mansoni eggs in a patient's serum even as compared with mature eggs of different Schistosoma (species specific) or of Schistosoma mansoni worms but not mature eggs (stage specific).