Immunohistopathological studies of blastomycosis: the use of labeled specific antigens in a hamster model of disease.

We applied a modified immunofluorescence and immunoperoxidase method, utilizing labeled Blastomyces dermatitidis antigens, to look for specific antibody-bearing B/plasma cells in the tissue infiltrates of blastomycosis lesions induced in hamsters. No specific anti-blastomyces antibodies were detectable by this method, although such antibodies were present in blood samples as demonstrated by routine immunodiffusion techniques. These studies suggest that humoral immune reactions do not play a major role in the pathogenesis of lesions of blastomycosis in hamsters.

Wegener's granulomatosis in childhood: cutaneous manifestations as the presenting signs.

Wegener's granulomatosis (WG), characterized by a necrotizing granulomatous vasculitis, is a rare systemic disease particularly infrequent in children. We report an unusual case of WG in a 16-year-old male patient in whom the cutaneous manifestations were the presenting signs that preceded the upper respiratory symptoms by several months. In addition, the finding of a calcified pulmonary lesion has never been reported in association with WG. Accurate diagnosis of early skin lesions is important in view of the available effective therapy. Clinical and pathologic features of WG and treatment are reviewed.

Release of acetylcholinesterase by cultured spinal cord cells.

The release of acetylcholinesterase from neurons was studied using cultured chick-embryo spinal-cord cells. Cells dissociated from 12-day-old chick-embryo spinal cords were grown in culture for 10-12 days. Numerous well differentiated spinal neurons were found after 7-10 days in culture. Acetylcholinesterase activity per dish increased by 60-fold from days 2-12. Acetylcholinesterase was released into the surrounding media by the cells when they were incubated either in the standard culture medium or the serum-free medium. Acetylcholinesterase release was significantly reduced when protein synthesis and microtubules were disrupted by cycloheximide and colchicine, respectively. Histochemical localization of acetylcholinesterase indicated that the synthesis and relase of acetylcholinesterase are attributable to neurons. Cultured chick-embryo brain and neuroblastoma cells also released acetylcholinesterase into the media. These results are discussed with regard to possible physiological roles for acetylcholinesterase secretion from neurons.