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Biomedical subjects

G Klein

Publications and source records attributed to G Klein.

At least 955 records · Page 53Linked to original sources
PubMed1979

Herpesvirus papio: state and properties of intracellular viral DNA in baboon lymphoblastoid cell lines.

Herpesvirus papio (HVP) is an indigenous B-lymphotropic virus of baboons (Papio sp.) present in latent form in baboon lymphoblastoid cell lines. It shares cross-reacting viral capsid and early antigens with the Epstein-Barr virus (EBV), and HVP DNA and EBV DNA show partial sequence homology. EBV-specific complementary RNA was employed here as a probe to investigate the physical state of the HVP DNA component in baboon lymphoblastoid cells after fractionation of cellular DNA by density gradient centrifugation. Five virus-producing cultures contained both free and integrated HVP DNA sequences while one non-producing cell line had two or three viral genome equivalents per cell in an apparently integrated form. Further analysis of one virus-producing line showed that the free HVP DNA fraction was composed of both linear and circular viral DNA. Contour length measurements of HVP circular DNA molecules by electron microscopy revealed that they were similar in length to the EBV circular DNA present in human lymphoblastoid cells.

Animals↗
PubMed1979

Growth of diploid, Epstein-Barr virus-carrying human lymphoblastoid cell lines heterotransplanted into nude mice under immunologically privileged conditions.

Human Epstein-Barr virus-carrying lymphoid cell lines which have been classified on the basis of studies on clonality and morphological, chromosomal and functional parameters as lymphoblastoid cell lines (LCL) of presumed non-neoplastic origin were inoculated intracerebrally into nude mice. All eighteen of them grew, killing the host mice within 7 to 25 days, except for 2 which grew more slowly. At autopsy, the brain of the nudes was found to be invaded by infiltrating lymphomas. Sixteen of these lymphomas, when recultured in vitro, gave rise to cell lines with growth properties and morphology indistinguishable from those of the inoculated LCL. Chromosomal examinations showed that 3/7 cell lines injected, which grew as lymphomas in the brain, were still normal diploid on reexplantation whereas the remaining four had become aneuploid. Four lines derived from intracerebral lymphomas (2 diploid, 1 aneuploid and 1 untested) were inoculated subcutaneously into adult nude mice. None of them grew. When the corresponding four original LCL lines were inoculated subcutaneously into newborn nude mice, they grew rapidly, but failed to do so in newborn normal mice or intracerebrally in adult normal mice. One such line, U-1450, was treated with anti-lymphocyte serum (ALS). Small nodules developed at the site of inoculation. From one nodule a cell line was cultured, 1450 ALSAD. It was morphologically indistinguishable from the line of origin. The lines obtained from nude mice inoculated with polyclonal LCL seem to have a restricted clonal representation, but were not monoclonal, as evidenced by analyses of their pattern of immunoglobulin synthesis.

Aneuploidy↗
PubMed1979

Relationship between the Epstein-Barr virus genome and nasopharyngeal carcinoma in Caucasian patients.

In order to explore whether undifferentiated nasopharyngeal carcinoma (NPC) shows a regular association with Epstein-Barr virus (EBV), regardless of the geographical and ethnic origin of the patient, a correlated histopathological and nucleic acid hybridization study was performed on biopsies from Caucasian patients with nasopharyngeal carcinomas and from various controls. Among 12 undifferentiated NPCs, 11 were positive for EBV-DNA, with multiple copies of the viral genome per cell. Serological tests showed elevated anti-VCA and anti-EA(DA) titers. Six NPCs with various degrees of squamous differentiation, four malignant lymphomas of the nasopharynx and seven carcinomas located outside the nasopharynx were EBV-DNA negative. These findings further stress the uniqueness and regularity of the association between EBV-DNA and undifferentiated NPC. Clearly, the association extends over geographical barriers and holds true not only in the previously studied, moderate-incidence African ethnic group, but also in the low-incidence Western patients.

Antibodies, Viral↗
PubMed1979

Serological detection of a polyoma-tumor-associated membrane antigen.

Syngeneic antisera raised against three polyoma tumors, SEYF-a SESO and SEWE, of strain ABY, A and ASW origin, respectively, contain antibodies directed against multiple specificities. One specificity is cross-reactive for the three polyoma tumors, but appears to be absent from a large variety of other tumors tested. Other, more "public" antigens are shared with a variety of other tumors of viral or non-viral origin. Five different public specificities of this type have been demonstrated and to some extent defined. Since the SEWE ascites tumor, with the shortest passage history, is much less liable to induce antibodies against the public specificities than the long-passaged SEYF-a and SESO, it is likely that the corresponding antigenic determinants arise as a result of passenger virus pick-up during continued passage, or are due to secondary cytogenetic changes.

Animals↗
PubMed1979

[Application of vasopressin in diagnostic radiology (author's transl)].

Vasopressin is demonstrated in 100 selected patients as a suitable drug to remove intestinal gas in diagnostic radiology. After subcutaneous injection of 10 IU Vasopressin only slight side-effects occurred in 35% of the patients. Under strict attention of the contraindications the use of Vasopressin is nearly without risk and leads to partially excellent results.

Digestive System↗
PubMed1979

[Treatment of decompensated valvular disease with nitroglycerin (author's transl)].

The effects of parenteral nitroglycerin after acute and continuous infusion were investigated in 12 patients with mitral and (or) aortic valvular disease (stage IV of the New York Heart Association) and severe therapy-resistant pulmonary congestion. Intravenous injection of 1 mg led to immediate and marked decrease of right atrial mean pressure, and pulmonary artery and pulmonary capillary mean pressures, whereas mean arterial blood pressure, stroke volume index, cardiac frequency, and cardiac index remained unchanged. With a dosage of 3-10 mg/h the pressure lowering of the right circulation could be sustained. Pressure lowering of the right circulation abolished pulmonary congestion and led to marked reduction of shortness of breath. The principle of venous pooling can thus not only be used successfully in cases of increased pulmonary capillary pressure due to primary myocardial insufficiency, but also in cases with pulmonary congestion due to decompensated valvular disease.

Adult↗
PubMed1979

Cell surface glycoprotein changes in Epstein-Barr virus-positive and -negative human hematopoietic cell lines.

It has previously been shown that differential fucose labelling of many normal and homologous tumor cells, followed by proteolytic release and degradation, yields glycopeptides which upon gel filtration shown an increase in fast-eluting glycopeptides for the tumor cells. This technique has now been applied to cell-surface glycoproteins of different human hematopoietic cell lines. These lines included Epstein-Barr virus (EBV)-carrying lymphoblastoid cell lines of presumed non-neoplastic origin, and malignant EBV-genome-positive Burkitt lymphoma and EBV-negative non-Burkitt lymphoma, leukemia and myeloma lines. As compared with normal peripheral lymphocytes, both the lymphoblastoid type of cell lines and the different types of lines of proven malignant ancestry contained the fast-eluting glycopeptides on their cell surface with very few exceptions. It is therefore concluded that (I) malignant conversion of human lymphoid cell in vivo is commonly, but not obligatorily, associated with a specific change in the composition of the fucosyl glycopeptides, and (2) EBV infection of B lymphocytes does not lead only to the well-documented immortalization in vitro but also, as a rule, to the same type of alteration in fucosyl glycopeptides as was demonstrated for the neoplastic cell lines. It proved possible to distinguish several categories of hematopoietic cell lines due to the effect that pretreatment of the glycopeptides with neuraminidase or mild acid exerted on their subsequent chromatographic behavior.

Burkitt Lymphoma↗
PubMed1979

Non-random duplication of chromosome 15 in murine T-cell leukemias induced in mice heterozygous for translocation T(14:15)6.

Trisomy of chromosome 15 is a highly regular feature of murine T-cell leukemogenesis. We have studied the chromosomal constitution of 7,12-dimethylbenza(a)anthracene (DMBA)-induced T-cell leukemias in C57BL X CBAT6T6 F1 mice. The CBAT6T6-derived chromosome T(14:15)6 was regularly duplicated whereas the C57BL-derived normal chromosome 15 was only present in one copy. It was concluded that the gene(s) that tend to duplicate in parallel with the neoplastic transformation of the prothymocyte to an overt leukemic cell have a greater chance of duplicating and/or may have a stronger promoting effect on leukemogenesis if stronger promoting effect on leukemogenesis if located on the CBA-derived, structurally rearranged T(14:15)6 than the corresponding genes located on the C57BL-derived normal chromosome 15.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1979

Moloney lymphoma cells express a polyprotein containing the GAG gene-coded p15 and the Moloney leukemia virus-induced cell surface antigen (MCSA).

The relationship between MCSA and the viral structural proteins in YAC Moloney lymphoma cells was further investigated by using membrane immunofluorescence and immunoadsorbent columns. As previously observed, MCSA showed only minimal capping and thereby differed in behaviour from gp70, p30 and p12 virion antigens. Whereas antibody-induced capping of gp70 did not change the membrane distribution of MCSA, co-capping was observed between MCSA and p30 and p12 gag protein antigens. This indicated that, whereas MCSA is distinct from gp70, it is linked to p30 and p12 on the membrane of living cells. It was then attempted to isolate MCSA on anti-p30 and anti-p15 immunoadsorbent columns from solubilized YAC cells. Contrary to what was expected, no MCSA was found to the anti-p30 column. On the other hand, a part (10-15%) of the MCSA was bound to the anti-p15 column, indicating that MCSA is linked to the gag p15.

Animals↗
PubMed1979

14q+ marker chromosome in an EBV-genome-negative lymph node without signs of malignancy in a patient with EBV-genome-positive nasopharyngeal carcinoma.

In a patient with an EBV-genome-positive nasopharyngeal carcinoma, an EBV-genome-negative inguinal lymph node without histological evidence of malignant lymphoma or metastatic carcinoma growth was found to contain a 14q+ marker chromosome, identified as an 8;14 translocation, in all cells analyzed. This observation indicates that chromosome aberrations may precede histological signs of malignancy. The possible implication of this finding in relation to the postulated role of the 14q+ marker and lymphoma development is discussed.

Adult↗
PubMed1979

Correlated expression of a B-lymphocyte-specific glycoprotein (gp27/35) and the EBV receptor/C3 receptor complex in sublines from the same Burkitt lymphoma.

A series of virus-producer and non-producer sublines, derived from the Burkitt lymphoma line Jijoye and its P3HR-1 clone, were previously found to differ in the expression of EBV receptors and, in parallel, C3 receptors. The differences could be related to an "internal selection" caused by the cytopathic P3HR-1 virus variant, favouring the growth of receptor-negative cells. We have now analyzed the same lines for the expression of a B-lymphocyte-specific glycoprotein (gp27/35). A close parallellism was found between the expression of the EBV receptor-complement receptor complex and the glycoprotein, measured by quantitative absorption. The results favour a relationship between gp27/35 and EBV/C3 receptor expression.

Antigen-Antibody Complex↗
PubMed1979

Detection of proteolytic (C 3-cleaving) activity on mouse mastocytoma (P 815) cells and other mouse cell lines by formation of cell contact with C 3-carrying mouse lymphocytes.

Mouse mastocytoma cells (P 815) formed rosettes with normal mouse spleen lymphocytes which had been coated with uncleaved human C 3; this interaction was clearly dependent on the amount of C 3. Lymphocytes treated with C 3 b or buffer alone were ineffective. Formation of cell contact could be inhibited by the presence of protease inhibitors such as diisopropyl fluorophosphate, phenyl methyl sulfonyl fluoride and tosyllysyl chloromethyl ketone. Seve n out of 13 different cell lines behaved like P 815 cells. The results strongly suggested that a proteolytic activity on mouse tumor cells led to a cooperation with uncleaved C 3 on a carrier cell to connect these two cells. We interpreted these data in analogy to the complement-dependent bridge formation mechanism (M. P. Dierich and B. Landen, J. Exp. Med. 1977. 146: 1484): uncleaved C 3, attached to mouse spleen lymphocytes as carriers, becomes cleaved by enzymes associated with the tumor cells tested; by this cleavage, the labile binding site is released on C 3 (nascent C 3 b) and anchors the C 3-carrying cell to the protease-carrying cell; since this labile binding site is short-lived, this process can be induced by membrane-associated proteases only. The nature of the proteases and the biological implications of this process are as yet uncertain.

Animals↗
PubMed1979

Differences in EBV receptor concentration between in vitro EBV-converted lymphoma sublines reflect biological differences between the converting viral substrains.

We have compared the EBV-receptor concentration of two originally EBV-negative human B-cell lymphoma lines, after in vitro conversion with the transforming B95-8 or the cytopathic P3HR-1 EB-viral substrain, respectively, into permanent EBV-carrying sublines. Receptors were measured by the quantitative EBV-absorption bioassay of Sairenji and Hinuma (1973). EBV receptor concentration of all P3HR-1 virus-converted sublines was significantly reduced, in comparison with the B95-8 virus-converted sublines. This suggests that cells with a low receptor concentration are more likely to survive the initial infection with the P3HR-1 viral harvest. The results further confirm the biological differences between the two EBV substrains.

Absorption↗