Histochemical observations onActinomyces bovisgranules

Abstract

The "clubs," found at the perifery of the "sulfur granules" in Actinomyces infection, are composed chiefly of a highly polymerlzed basic protein rich in guanidyl, indole, and phenolic groups; sulfhydryl groups are absent. The clubs appear to be made of a material actively secreted by the filaments. It is hypothesized that some product or products of animal protein decomposition which are metabolized by the actinomycete trigger and maintain club formation in vlvo, and that the club prevents phagocytosis or enzymatic digestion of the filaments on the one hand but proscribes further growth of the filaments on the other. New growth of the parasite takes place by extension of non-clubbed filaments at the perifery of the granule or by deposition of coccoid elements phagocytized by leucocytes.The literature is lacking in information on the nature of the hyaline "clubs" often found at the perifery of the "sulfur granule," and on the mode of club formation in Actinomyces infection. In these experiments the nature of the clubs is examined and the results compared with (I) the observations of others on stained material, and (2) past experimental observations and opinion on club formation. MATERIALS AND METHODSFormalin fixed pieces of human lung from a patient whose lungs had previously yielded cultures of A. boris were washed overnight in running tap water then embedded either in paraffin or carbowax. With the exception of the test for arginine, the stain methods used are described by Pearse (1961). These included tests for carbohydrates (periodic acid-Schiff, Alcian blue)

Dimorphism in Candida Albicans. I. Morphology- Dependent Changes in Cellular Content of Macromolecules and Respiratory Activity

“…The finding of NICKERSON and VAN Ru (5) that addition of a small amount of cysteine to the growth of a divisionless strain of C. albicans on solid medium promotes cellular division in this strain and the subsequent work of NICKERSON and his collaborators (6)(7)(8) led them to the postulation that the extension of cell wall or the development of the filamentous form ensues as a consequence of the inhibiition of normal cell division, unless a specific disulfide-reducing process can be maintained in order. Similar results were also reported by others (9,10). Carbon dioxide is known to have a morphogenetic influence in Sporotrichum schenckii (11), Trichophyton mentagrophytes (12), and Mucor rouxii (13).…”

Interaction of Actinomyces Organisms with Cationic Polypeptides I. Histochemical Studies of Infected Human and Animal Tissues

“…The mildly periodic acid-Schiff-reactive carbohydrate material of the hyaline clubs described here was also seen by Widra (40) in human tissue lesions. Electron micrographic studies of A. bovis colonies from bovine lesions have demonstrated an extracellular polysaccharide-protein complex covering the filaments and holding them together (29).…”

“…Results of these 76:191, 1960;Bacteriol. Proc., p. 126, 1961), coincide with findings of Widra (40). Development of acidophilic staining by viable and heatkilled Actinomyces organisms in vitro indicates that the cationic component of tissue colonies is of host rather than microbial origin.…”

“…In human tissues, cationic polypeptides appeared more resistant to proteolytic degradation. This was also noted by Widra (40). Arginine-rich protamines applied to bacteria in vitro are more resistant to hydrolytic removal by trypsin than are histones (34).…”

“…At this time, no single theory has been generally accepted. Some investigators (3,6,29,39,40) favor a theory that the marginal club forms common to Actinomyces colonies in infected tissues are produced by the microorganism. Others (11,20,25) contend that the clubs are products of the host.…”