[The ultrastructure of human pituitary adenomas (author's transl)]. / Zur Ultrastruktur menschlicher Hypophysenadenome

34 pituitary adenomas were examined by light and electron microscopical methods. Slices of tumor tissue fixed in formaldehyde or Bouin's solution, respectively, and embeded in paraffin were stained by hematoxylin-eosin, Goldner's method (including Orang G), periodic acid Schiff (PAS) reaction, and in some cases by Herlant's tetrachrom. The ultrastructure was studied using tumor tissue fixed in glutaraldehyde within 1 hour after removal. The adenomas were classified by their light microscopical characteristics as chromophilic or chromophobe tumors. Employing the PAS reaction and Goldner's staining method, 27 adenomas were found to give intense or weak staining reactions. By electron microscopical investigation , all the adenomas studied were seen to contain secretory granules more or less densely packed within the cytoplasm. The number of these granules was strongly correlated with the intensity of the tinctorial properties of the tumor tissue. Out of 11 acidophilic adenomas, 10 were observed consisting of typical STH cells. 4 acromegalic patients were found to possess heavily or poorly granulated STH cell adenomas (two patients in each of these groups). One patient with a clinical history of liver cirrhosis and gynecomastia was observed bearing an acidophilic (and erythrosinophilic) adenomatous hyperplasia of prolactin cells, 13 tumors consisted of cells exhibiting almost weak amphophilic staining properties and secretory granules of 100-250nm diameter, thus resembling cells which have been reported to produced ACTH. One of the patients suffering from these adenomas, showed the clinical signs of M. Cushing. By ultrastructural criterions, 3 adenomas with PAS-positive tumor cells were considered to be composed of gonadotropic cells. Only 7 adenomas were observed which did not give any chromophilic reaction. These tumors consisted of extreme poorly granulated cells which could not be significantly associated with one of the pituitary hormones by their morphological properties. In respect of the abundance of mitochondria, 4 out of the adenomas were designated as oncocytic tumors.

Further evidence for common antigens in intracytoplasmic A particles of mouse mammary tumors and B type virions of murine milk.

Using the indirect immunofluorescence technique and radioimmunoprecipitation test (RIP test) according to ABELEV and ELGORT (1970) immunological investigations intracytoplasmic A particles isolated from mouse mammary tumors were performed. In order to purify the virus particles sucrose gradients were employed according to TANAKA et al. (1972) and in some details according to SMITH and WIVEL (1973). In immunofluorescence studies on mammary tumor slices a complete cross-reaction between antisera against A particles from mammary tumors and MTV-B particles from mouse milk was observed. Both kinds of antisera reacted in identical fluorescence pattern types with intracytoplasmic A particle clusters and with extracellular accumulations of B type virions, respectively, in tumors of different histological structures. RIP test studies suggest that these cross-reactions are attributed to three common antigens in A and B type viruses. Thus, there does not remain any doubt that intracytoplasmic A particles in murine mammary tumors are MTV-related. All these A particles antigens were identically detected using an antiserum against A particles isolated from mouse leukemia cells (serum kindly provided by Dr. TANAKA). The biological role of intracytoplasmic A particles in mouse tissues is discussed. In contrast to the precursor theory, it is believed that they could represent something like a nonsense way of particle maturation in MTV-infected cells.

Mammary tumour virus (MTV)-specific immune complex deposites in renal glomeruli of MTV-infected tumour-free mice.

Using direct and indirect immunofluorescence tests MTV-specific immune complex deposits were found in tumour-free female mice of the strains C3H/Bln, CBA/Bln, XVII/BlnfCBA/Bln, and CBA/BlnfXVII/Bln. These deposits consist of immunoglobulin, complement, and MTV antigen(s). The immune complex deposition increases with age. Antibodies eluted from renal tissue homogenate react with both MTV-A and -B particles in immunofluorescence tests performed on mouse mammary tumour slices. By these results the earlier finding of age-dependent spontaneously occurring anti MTV antibodies in naturally MTV-infected mice is confirmed and completed.