Since somatostatin lacks a tyrosine residue that can be readily iodinated, three different radiolabeling procedures for synthetic cyclic Tyr^som'atostatin were compared with each other. In addition, cyclic somatostatin was radiolabeled with the Bolton-Hunter reagent. The radiolabeled antigens were purified by G-25 Sephadex adsorption chromatography and thus separated from unreacted components. ...

A double antibody radioimmunoassay (RIA) for rat apolipoprotein A-I is reported. The ApoA-I isolated from delipidated HDL by gel filtration yielded a single band on polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS), and its amino acid composition resembled that reported by others. ApoA-I was iodinated by lactoperoxidase and the resulting 125I-apoA-I was purified by gel filtrati...

Antigenic compounds from the surface of leukemic myeloblasts are shed in vitro on short-term culture. Blast cells radiolabeled by lactoperoxidase iodination release soluble compounds that react immunologically with alloantisera to leukemia-associated antigens. Partially characterized soluble antigens were used to raise heteroantisera in monkeys that are selectively reactive with leukemic myelob...

Aromatic amines are mammary carcinogens in rodents and exposure to aromatic amines may be associated with increased risk of breast cancer in women. Peroxidases present in milk can oxidize aromatic amines to reactive electrophiles which bind to DNA and induce mutations. Hydrogen peroxide, required for peroxidase-dependent oxidations, is supplied by milk xanthine oxidase and by the respiratory bu...