Attempts to isolate virus from human brain tumors

In order to study the viral etiology of human brain tumors, attempts were made to isolate cytopathogenic agents from human brain tumors by the tissue culture of tumor tissues and by the mixed culture of tumor tissues with HeLa cells. Five glioblastomas, a mixed form of glioblastoma and fibrosarcoma, two astrocytomas, two ependymomas, two meningiomas, an oligodendroglioma, a spongioblastoma polare and a choroid plexus papilloma were studied. In the tissue culture, besides the cells which appeared to be the tumor parenchymal cells, varying amounts of fibroblastic cells appeared in all the tumors tested and they increased with the prolongation of the culture period. In any of the tumors tested, no cytopathogenic agents were detected by either the culture of tumor tissues or the mixed culture of tumor tissues with HeLa cells. From the virological point of view, the significance of these negative results was discussed.</p

Infection of human embryonic skin-muscle tissue culture cells with adenovirus type 12

,The effect of infection of human embryonic skin-muscle cell cultures with adenovirus type 12 has been studied. When maintained in YLE containing 20 per cent bovine serum, human embryonic skin-muscle tissue culture cells developed little or no cytopathogenic effect for about 50 days after inoculation of adenovirus type 12, though a small amount of virus was always detected in the overlying medium. From day 50&#8764;60, CPE started appearing and spread over 90 per cent of cells accompanied with the increase of virus in the overlying medium. The addition of human serum to the maintenance medium inhibited the virus release. After removal of human serum about 16&#8764;37 days after its addition, virus-and, later, CPE also-again started appearing. The second virus release-and CPE also-was inhibited by addition of human serum to the medium. When maintained in the medium with human serum for about 200 days, the removal of human serum did not result in the appearance of virus or CPE. The virus isolated from the overlying medium of these cells during the whole process of the experiment was always highly oncogenic to newborn hamsters. Diluted adenovirus-12-immune rabbit serum also showed the effect similar to that of human serum. But, regardless of its much higher antibody titer, the effect of this diluted adenovirus-12-immune rabbit serum was weaker than that of human serum. In one of cell cultures, rapidly growing cells appeared 212 days after virus inoculation. But the available data suggest that these are the cells transformed rather spontaneously in tissue culture than by adenovirus type 12.</p

Electron microscopic, immunofluorescent and virological studies on a rhabdomyosarcoma in epidermodysplasia verruciformis

A subcutaneous tumor of a patient with epidermodysplasia verruciformis was studied by the light microscopy, the electronmicroscopy and the immunofluorescent test. The tumor cells were histologically pleomorphic and electronmicroscopically contained varying amounts of cytoplasmic filaments without Z-band formation. The antimyosin serum stained the tumor cells, showing their myogenic origin. No virus or virus-like particles were observed in the tumor. Tumor antigens stainable by the patient's serum were not detected. Hamsters inoculated with the tumor extract at birth developed no noticeable diseases.</p

A Rapid Method for the Detection of Papillomavirus in Warts : The Fre­quency of Virus Detection in Various Types of Warts

A rapid method was devised for the detection of virus particles in wart specimens. The upper layer of warts was cut perpendicularly to the surface, and the freshly cut surface was lightly touched to an electron microscope grid. The grid was then stained with a small drop of phosphotungstate and observed electron microscopically. On the specimen grid thus prepared, papillomavirus particles were easily discriminated from tissue debris. Papillomavirus particles were detected in 71% of verrucae plantares, 78% of verrucae palmares, 50% of verrucae vulgares and 75% of condylomata acuminata by the present method.</p

Effect of injection of adenovirus type 12 in adult hamsters

Large doses of adenovirus type 12 were injected intraperitoneally into adult hamsters, and development of tumors and other pathological findings were studied in comparison with those in hamsters injected when newborn. Doses of 38~47 TCID60 per gram body weight produced tumors in 3 of 12 hamsters injected at 37~57 days of age. A dose of 170 TCID60 per gram body weight produced tumors in one of 18 hamsters injected at 61~71 days of age, but in none of 18 hamsters injected at 147~174 days of age, while the same dose per gram body weight produced tumors in 24 of 26 hamsters injected when newborn. In hamsters injected at adult ages, the number of tumors per animal decreased and the latent period for tumor development became very long as compared with those in hamsters injected when newborn. Regardless of the age at the time of injection, acute inflammatory change was observed in the peritoneum which later developed into various degrees of peritoneal adhesion. Adenovirus type 3 also induced the peritoneal adhesion. Histology of tumors was studied and discussed.</p

Lifelong persistent infection of hamster brain by human adenovirus type 6.

To establish an experimental persistent infection of the brain with human adenoviruses, adenovirus type 6 (ad 6) was inoculated intracerebrally into young adult hamsters. Hamsters appeared languid for a few days after inoculation, but recovered rapidly. By cocultivation of tissue fragments with HeLa cells, ad 6 was always recovered from the brains of hamsters throughout their lives, as long as 29 months, indicating the establishment of a lifelong persistent infection. Except for the first few days after inoculation, however, attempts to recover virus by inoculation of tissue extracts onto HeLa cells or by cultivation of tissue fragments alone were unsuccessful.</p

Two human papillomavirus DNAs molecularly cloned from a patient with epidermodysplasia verruciformis: restriction maps.

Two distinct human papillomavirus (HPV) DNAs (MY-1 and MY-2) were molecularly cloned from the benign skin lesions of a patient with epidermodysplasia verruciformis. The restriction map of MY-1 was the same as that of HPV 3a. The map of MY-2 appeared to be different from those of any HPVs reported in the literature. MY-2 did not cross-hybridize with MY-1 or the DNAs of HPV types 1, 2 and 4 under stringent conditions.</p

Human AK2 links intracellular bioenergetic redistribution to the fate of hematopoietic progenitors

AK2 is an adenylate phosphotransferase that localizes at the intermembrane spaces of the mitochondria, and its mutations cause a severe combined immunodeficiency with neutrophil maturation arrest named reticular dysgenesis (RD). Although the dysfunction of hematopoietic stem cells (HSCs) has been implicated, earlier developmental events that affect the fate of HSCs and/or hematopoietic progenitors have not been reported. Here, we used RD-patient-derived induced pluripotent stem cells (iPSCs) as a model of AK2-deficient human cells. Hematopoietic differentiation from RD-iPSCs was profoundly impaired. RD-iPSC-derived hemoangiogenic progenitor cells (HAPCs) showed decreased ATP distribution in the nucleus and altered global transcriptional profiles. Thus, AK2 has a stage-specific role in maintaining the ATP supply to the nucleus during hematopoietic differentiation, which affects the transcriptional profiles necessary for controlling the fate of multipotential HAPCs. Our data suggest that maintaining the appropriate energy level of each organelle by the intracellular redistribution of ATP is important for controlling the fate of progenitor cells