J. Donald Hare

Listeriosis complicating lymphoma: Report of four cases and interpretive review of pathogenetic factors

Abstract Described herein are three adult patients with Hodgkins disease and one with lymphosarcoma in whom a serious intercurrent infection with Listeria monocytogenes developed. An analysis of predisposing factors points out the behavior of Listeria as a facultative intracellular parasite, a category of pathogens including the tubercle bacillus. The critical role of host macrophages in defense against this group of pathogens is emphasized and discussed in relation to the underlying disease, corticosteroid therapy and cytotoxic drugs. Finally, hypothetical comments are offered concerning host resistance in Hodgkins disease or lymphosarcoma, and its possible relationship to the expression of delayed hypersensitivity.

The role of phosphorylation in the uptake of thymidine in mammalian cells.

SummaryThymidine uptake into the acid-soluble fraction of several hamster cell lines differing in levels of thymidine kinase was examined. Uptake is correlated directly with the level of this enzyme, a kinase-deficient line showing the lowest uptake rate. At low extracellular concentrations the major portion of the uptake that occurs is related to phosphorylation, while at higher levels passive diffusion plays a proportionally greater role. This pattern holds for all cells tested except the kinase-deficient line, which shows no evidence of a phosphorylation-related process. By contrast, urindine uptake shows both a regulated and a passive process in all lines tested. The controlled uptake of these two compounds correlates with the ability of the cell to phosphorylate each nucleoside. The results suggest that phosphorylation may act as a regulating factor for pyrimidine nucleoside uptake across the cell membrane.

Transplant immunity to polyoma virus-induced tumor cells IV. A polyoma strain defective in transplant antigen induction☆

Abstract Differences in the capacity of polyoma virus strains to stimulate transplant resistance in hamsters as well as induce measurable quantities of the polyoma-specific transplant antigen in tumor cells were demonstrated. The large (Ip-D) and small plaque (sp-D) virus strains isolated by Dulbecco from the LID-1 polyoma virus isolated at the National Institute of Allergy and Infectious Diseases, were found to be defective in their capacity to stimulate transplant immunity against tumor cell lines known to contain the polyoma transplant antigen which had been induced by several other strains. Furthermore, both strains were defective in the quantity of transplant antigen induced in tumor cells. There was no correlation between the lack of transplant antigen activity and the neoplastic characteristics of the tumor cells induced by these virus strains; this finding suggests that the cell membrane alteration responsible for the transplant antigen function does not play a direct, mediating role in the neonlastic event.

Ultrasonic treatment of tumors: I. Absence of metastases following treatment of a hamster fibrosarcoma

Abstract The rate of metastasis has been compared for a hamster fibrosarcoma line treated either with ultrasound or by surgical excision. Continuous wave, 5 MHz ultrasound at 3 W/cm 2 for 6–8 min brought tumor temperatures to 60–70°C. The animals were observed over a period of 12 weeks. The ultrasound treatment effectively eradicated the local tumor. There was no indication of induction of metastasis by the treatment.

Role of hydrogen and disulfide bonds in polyoma capsid structure

Abstract The relationship between polyoma virus (Py) structure and function was studied. It was found that the virus was relatively stable under conditions which disrupt hydrogen and/or hydrophobic bonds, i.e., intermediate levels of concentrated urea, high pH, and heat. However, addition of the disulfide bond breaking reagents 2-mercaptoethanol or dithiothreitol (DTT), significantly potentiated the destructive effect of hydrogen bond disruption. Furthermore, it was found that the reaction with DTT was rate-limiting in the presence of urea but not at a pH of 10.5. This finding suggested that a barrier to the diffusion of DTT existed which was altered by alkaline treatment. Organic and inorganic mercurials were found not to influence viral function suggesting that free SH bonds were not structurally significant. Electron microscopy demonstrated that treatment at pH 10.5 followed by heating at 37° for 60 minutes, 56° for 30 minutes or with DTT caused the dissociation of virus particles into poorly resolved subunit material without recognizable capsomer structure. Following such extensive disaggregation, viral proteins no longer formed precipitin bands with anti-whole virus antiserum. A small plaque strain of Py was more susceptible than a large plaque strain to inactivation at pH 10.5 in the presence of DTT. These findings suggest that relatively inaccessible disulfide bridges contribute to the structural integrity of the virus particle and its immunochemically reactive antigenic determinants. Furthermore, differences between plaque size variants may be related in part to disulfide bond position or number.

A new type of variation among the polyoma viruses characterized by cytoplasmic accumulation of capsid antigen

Abstract By immunofluorescent techniques, capsid antigen of the 3049 strain of polyoma virus was found in the cytoplasm early in the infectious cycle followed by its gradual appearance in the nucleus. This is distinct from the capsid antigen of other polyoma strains, which reaches concentrations sufficient to be visualized only in the nucleus. This characteristic, termed CyC+, is stable and is unrelated to antigenic type or plaque size as well as multiplicity of infection. The synthesis of “T” antigen and infectious virions is normal. Capsid antigen formation is inhibited by DNA synthesis inhibition as in other polyoma strains. Of interest is the finding that capsid antigen appeared only in the nucleus of hamster embryo cells, perhaps providing a unique example of host control over a viral function.

Transplant Immunity to Polyoma Virus Induced Tumors. I. Correlations with Biological Properties of Virus Strains.

SummaryEvidence is presented to show that 2 polyoma strains, 3049-H+ and 210-H-, which differ in a number of biological characteristics, induce similar degrees of transplant immunity in adult hamsters, and induce similar “antigens” in tumors produced in neonatal animals. A third strain, Dulbec-cos “large plaque” virus, is nearly identical with the 3049-H+ strain, but fails to stimulate transplant immunity against tumor cells induced by the 3049-H+ virus; instead, it appears to enhance tumor growth. Evidence is also presented to show that polyoma virus replicates poorly in the hamster (as measured by virus content of liver, spleen, and kidney) and may localize more specifically in an immunologically active organ, the spleen.Summary Evidence is presented to show that 2 polyoma strains, 3049-H+ and 210-H-, which differ in a number of biological characteristics, induce similar degrees of transplant immunity in adult hamsters, and induce similar “antigens” in tumors produced in neonatal animals. A third strain, Dulbec-cos “large plaque” virus, is nearly identical with the 3049-H+ strain, but fails to stimulate transplant immunity against tumor cells induced by the 3049-H+ virus; instead, it appears to enhance tumor growth. Evidence is also presented to show that polyoma virus replicates poorly in the hamster (as measured by virus content of liver, spleen, and kidney) and may localize more specifically in an immunologically active organ, the spleen.

Antigenic variation among polyoma viruses from different sources demonstrated by plaque neutralization

The antigenic relationship between strains of polyoma virus isolated in three independent laboratories was studied by a plaque neutralization technique. The large-plaque strains showed the greatest cross-reactivity. In contrast, small-plaque strains differed significantly from the large-plaque strains derived from the same virus isolates. In addition, each small-plaque strain differed significantly from each other. The antigenic characteristic was stable on plaque purification, terminal dilution selection, or passage in hamster embryo cell cultures.

Transplant Immunity to Polyoma Virus Induced Tumors. III. Evidence for Heterogeneity Among Transplant Antigens in vivo.

Summary The ability of 2 polyoma virus strains, 3049 and lp-D, to produce transplant immunity in adult hamsters against tumor cells induced by both strains was studied. The 3049 virus immunized hamsters against tumor cells produced by itself, but tended to enhance the growth of lp-D virus-induced tumor cells. On the other hand, the lp-D virus produced little or no immunity against its own tumor cell, but enhanced the growth of 3049 virus-induced cells. X-irradiated tumor cells induced by the 3049 virus, when given to adult hamsters, enhanced the growth of both 3049 and lp-D tumors. Possible explanations for these paradoxical results, based on the presence of at least 2 transplant antigens, were discussed.

A simplified sampling technique for studying radio-isotope labelling of cells in culture.

Summary A simplified technique for studying the uptake of radio-isotope labelled precursors in normal and neoplastic cells in tissue culture is described. It makes use of the fact that uniform discs can be cut from the cell-covered bottom of plastic tissue culture dishes with a modified cutting tool. The discs may then be counted directly in an automatic gas flow isotope counter or mounted on glass slides and coated with photographic emulsion for high resolution autoradiography or stained by a variety of cytological procedures. Rapidity and simplicity of handling as well as reproducibility of samples are distinct advantages.SummaryA simplified technique for studying the uptake of radio-isotope labelled precursors in normal and neoplastic cells in tissue culture is described. It makes use of the fact that uniform discs can be cut from the cell-covered bottom of plastic tissue culture dishes with a modified cutting tool. The discs may then be counted directly in an automatic gas flow isotope counter or mounted on glass slides and coated with photographic emulsion for high resolution autoradiography or stained by a variety of cytological procedures. Rapidity and simplicity of handling as well as reproducibility of samples are distinct advantages.