Search PubMed⌕ Search

Biomedical subjects

T Greenland

Publications and source records attributed to T Greenland.

67 records · Page 4Linked to original sources
PubMed1980

Retroviral antigens on gs- chf- leukocytes.

It has recently been suggested that the endogenous retroviruses present in many different species might be involved during stimulation of the immune system of their hosts. We have now studied the expression of two avian retroviral antigens p27 and gp85 in chicken lymphoid cells by indirect immunofluorescence (IIF) and by complement-dependent microcytotoxicity (CDM). We have now found that these viral antigens are expressed in peripheral blood leukocytes of adults and embryos and in splenic and bursal lymphocytes of Spafas gs- chf- chickens but they are not expressed in fibroblasts cultured from the feather follicles of the same individual adult birds nor in fibroblasts cultured from embryos of the same flock. The differential expression of viral antigens in leukocytes may be related to a specific property or function of these cells.

Animals↗
PubMed1980

Studies on platelet glycoproteins in Glanzmann's thrombasthenia using 125I-labelled lectins.

Glycoproteins (GP) of Glanzmann's thrombasthenia (GT) and normal platelets were separated on sodium dodecyl sulphate (SDS) polyacrylamide slab gels and identified by their binding of 125I-labelled lectins having different sugar specificities. This highly sensitive technique showed that in thrombasthenic platelets, glycoproteins in the positions of IIb and III (IIIa) were greatly reduced when compared to normal platelets. After incubation with neuraminidase, IIb became undectable. GT platelet glycoproteins I, IV (IIIb), and high molecular weight GPs bound 125I-lectins more strongly than those in normal platelets, showing that there are drastic changes in the carbohydrate moieties of these major GPs.

Blood Platelets↗
PubMed1980

Morphometric studies of cell nuclei by means of image analysis and computer data processing.

A review of the recent results of the authors in the field of morphometric studies of Feulgen-stained cell nuclei is given. The data acquisition with Quantimet 720 and data processing with computer were used in the study. The discrimination between male and female cell nuclei from buccal smears on the basis of morphometric data is described. The morphometry-based classification of cells from vaginal smears according to the computer procedure is presented. The results are discussed in the context of the general strategy of morphometric work.

Animals↗
PubMed1979

A study of the measles virus-induced proteins incorporated into the cell membrane.

The polypeptide composition of a measles virus isolate from a case of subacute sclerosing panencephalitis, the Halle strain, and the distribution of these polypeptides in the cell membrane have been investigated. In purified virus preparations, four major polypeptides were identified with molecular weights corresponding to 80K, 62K, 42K and 37K daltons. A minor band was found at 69K and several others with molecular weights +/- 100K. By specifically labeling the proteins exposed at the surface of BGM cells either persistently or lytically infected with the Halle virus, it was shown that only the 80K and 42K viral polypeptides were present in the cell membrane. Furthermore, it was observed that PAGE profiles of cellular polypeptides differed between infected and noninfected cells.

Antigens, Viral↗
PubMed1978

Interactions of Shope papilloma virus with some other DNA viruses.

The interactions of Shope papilloma virus (SPV) with primate and rabbit cells in tissue culture have been investigated. The rabbit cell cultures were derived from normal epidermis, from SPV-infected epidermis, from SPV-induced papillomas, and from an SPV-associated carcinoma. None of these cell cultures, whether infected in vitro with SPV or derived from tissues infected in vivo, ever produced infectious SPV or even detectable viral antigens. Some other DNA viruses behaved differently in cells which had been in previous contact with SPV either in vitro or in vivo. Adenovirus type 5 multiplies better in human cells infected 24 h previously with SPV than in the untreated controls. The production of infectious virions of either herpes simplex virus or Shope fibroma virus is reduced in cells derived from SPV-induced papillomas or carcinoma, due, apparently, to a defect in viral maturation. Of the rabbit cells, only those derived from in vivo infected tissue, or those previously infected in vitro with SPV, could be transformed by SV40. The rabbit cell lines derived from papillomas or carcinoma differed from their counterparts derived either from normal epidermis or from tissue infected 24 hrs before biopsy, in their karyotype, and in their ability to grow in soft agar. Similar karyotypic alterations were induced in cells derived from healthy epidermis by infection in vitro with SPV.

Adenoviruses, Human↗
PubMed1977

[Tumor specific surface antigen in the culture medium of a rat cell line transformed by Rous sarcoma virus].

TSSA is detected on transformed cells by a mixed hemadsorption reaction. The medium of cultures of Rat cells transformed by Rous sarcoma virus (Prague strain, sub-group C) contains a soluble factor which specifically inhibits this reaction. This factor thus possesses the antigenic activity of TSSA which is associated with the presence of a component of molecular weight 42,000 by polyacrylamide gel electrophoresis.

Antigens, Neoplasm↗
PubMedDate not supplied

Visna-maedi virus-induced expression of interleukin-8 gene in sheep alveolar cells following experimental in vitro and in vivo infection.

Visna-maedi virus is a lentivirus which causes inflammatory disorders in sheep, including a chronic interstitial lung disease resembling that observed in human immunodeficiency virus type 1 (HIV 1) infection. In view of our previous demonstration of the production of neutrophil chemotactic activity by alveolar macrophages, and given the lymphocytic and neutrophilic nature of the alveolar cell infiltrate in both naturally and experimentally infected animals, we hypothesized that interleukin-8 (IL8) could be a candidate for at least part of the chemotactic activity we described. In this study, we investigated IL8 mRNA expression following visna-maedi virus infection. Northern analysis of total RNA using an ovine IL8-specific probe demonstrated that the IL8 gene is upregulated in alveolar macrophages as a consequence of in vitro infection and in alveolar cells from experimentally infected animals. Using a semi-quantitative RT-PCR method, we showed that various levels of IL8 mRNA are expressed by alveolar cells from infected animals and that they correlate with the intensity of the lesions. In conclusion, visna-maedi virus is able to induce IL8 mRNA expression in sheep alveolar cells. Results from in vivo infected animals suggest that IL8 could play a role in the early build-up of visna-maedi virus-induced lesions.

Animals↗
PubMedDate not supplied

Interstitial lung disease in feline immunodeficiency virus (FIV) infected cats.

Postmortem bronchoalveolar lavage of feline immunodeficiency virus-infected cats indicated an alveolitis process, and histological examination of their lungs confirmed the occurrence of alveolitis, parenchymatous lymphoplasmocytic infiltration and myomatosis. Similar lymphoid interstitial pneumonitis has been described in human and animal lentiviral diseases: lymphocytic interstitial pneumonitis in HIV-1-infected human beings, and maedi in sheep infected by the maedi-visna virus. Such lymphoid interstitial pneumonitis may thus be a common feature of lentiviral infections.

Animals↗
PubMedDate not supplied

Increased expression of tissue factor mRNA and procoagulant activity in ovine lentivirus-infected alveolar macrophages.

To link ovine lentivirus infection to lung tissue damage, we studied the procoagulant response in alveolar macrophages from experimentally infected lambs and in in vitro infected alveolar macrophages. We cloned ovine tissue factor cDNA and analysed its in vitro expression by Northern blotting. Visna-maedi virus induced tissue factor mRNA. In order to correlate this mRNA induction with its cellular function, we analysed macrophage procoagulant activity after in vitro and in vivo infection. The procoagulant activity was increased by interaction with the virus in both cases. Thus, visna-maedi virus-induced expression of tissue factor mRNA was associated with enhanced macrophage procoagulant activity. These findings indicate an active role of alveolar macrophages in the pathogenesis of these inflammatory lung lesions.

Animals↗