Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Induction of HLA expression in Daudi cells after cell fusion (1977)
    Springer
    Immunogenetics 5 (1977), S. 423-436 
    Details
    ISSN: 1432-1211
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The Daudi cell line, established from a Burkitt lymphoma, has recently been found to be HLA- andΒ 2-microglobulin-negative, although it expresses B lymphocyte alloantigens. This report is concerned with the reexpression of HLA-A10, B38, and B17 on the Daudi cell, after cell fusion with another human cell line (Raji) or with mouse fibroblasts. In the latter fusion, the same HLA specificities are re-expressed, but not humanΒ 2-microglobulin while mouseΒ 2-microglobulin andH-2 could be detected. No such reexpression was observed when Daudi was fused with the F9 mouse teratocarcinoma, which lacks mouseΒ 2-m andH-2. No HLA activity (alloantigenic and xenogenic activity) was detected in the membrane or cytoplasm of Daudi, using salt extraction and sonication. Therefore we postulate thatΒ 2-microglobulin could be necessary for the expression and possible synthesis of the HLA antigen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01570501
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Histo-blood group p: biosynthesis of globoseries glycolipids in EBV-transformed B cell lines (1996)
    Springer
    Glycoconjugate journal 13 (1996), S. 529-535 
    Details
    ISSN: 1573-4986
    Keywords: P blood group ; glycolipids ; glycosyltransferases ; B cell lines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The genetic and biosynthetic basis of the histo-blood group P-system is not fully understood. Individuals with the rare p phenotype do not express the three glycolipid antigens (Pk, P and P1) of this system, probably because of deficiencies in glycosyltransferases involved in their biosynthesis. Iiukaet al. [Iiuka S, Chen SH, Yoshida A (1986)Biochem Biophys Res Commun 137: 1187–95], however, previously reported that detergent extracts from an EBV-transformed B cell line derived from a p individual did express the glycosyltransferase activity (Pk transferase) assumed to be missing in this blood group status. Here, we have reinvestigated the antigen expression and glycosyltransferase activities in two p individuals by analysing EBV-transformed cell lines as well as erythrocytes to confirm the blood group P status. The thin layer chromatography glycolipid profile of extracts from erythrocytes and EBV-transformed B cell lines showed characteristic accumulation of lactosylceramide and absence of Pk and P antigens. Glycosyltransferase activities of the B cell lines were analysed using glycolipid substrates and both extracts were found to contain lactosylceramide synthetase and P transferase activities but to be completely devoid of Pk transferase activity. The presented data indicate that p individuals, in contrast to previous reports, do not express a functional Pk glycosyltransferase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00731440
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Possible role of nonprotein components of the plasma membrane in CD4-dependent membrane fusion and HIV entry (1996)
    Springer
    Perspectives in drug discovery and design 5 (1996), S. 143-153 
    Details
    ISSN: 1573-9023
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary In most situations, HIV enters a cell by a membrane fusion process mediated by its envelope proteins (Env, gp120/gp41), which is triggered by the interaction of gp120 with CD4. Membrane fusion and virus entry probably require other human-specific molecule(s) (often designated as ‘fusion cofactors’), since: (i) CD4+ cells of nonhuman origin are resistant to HIV entry and Env-mediated fusion; and (ii) heterokaryons formed between nonhuman CD4+ cells and human CD4− cells are permissive to these processes. Most types of human cells, including red blood cells (RBC), were found to complement murine cells and must therefore express the fusion cofactors. The complementation efficiency was not reduced if RBC membranes (ghosts) were used instead of intact RBC, or if RBC were extensively digested with proteinase K or pronase. These experiments confirm that the fusion cofactors are associated to the plasma membrane, and raise the possibility they could be nonprotein components, in particular complex lipids. Among these, glycosphingolipids (GSL) seem to have a diversity consistent with the existence of human-specific types. This hypothesis could explain why CD4+ cells could not be rendered permissive to HIV entry by transfection of human DNA, or by forming stable hybrid cell lines bearing human chromosomes. Until now, attempts to complement CD4+ murine cells by transferring GSL-enriched lipidic fractions prepared from human cells have not been successful. Also, treatments with enzymes or metabolic inhibitors aimed at reducing GSL expression did not seem to alter the permissivity of CD4+ human cells. However, these experiments have a number of technical limitations, and in spite of these negative results, the role of complex lipids in HIV entry deserves further investigation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02174009
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Phenotypic characterization of Ewing sarcoma cell lines with monoclonal antibodies (1986)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 31 (1986), S. 289-296 
    Details
    ISSN: 0730-2312
    Keywords: histogenesis ; antigenic phenotype ; flow cytometry ; N-CAM ; HNK-1 monoclonal antibody ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The histogenesis of Ewing sarcoma, the second most frequent bone tumor in humans, remains controversial. Four Ewing cell lines were analyzed by immunological methods. A panel of antibodies directed to T, B, and myelomonocytic markers gave negative results. Surface antigens recognized on Ewing cells were found to be related to the neuroectoderm lineage. Ganglioside GD2, a marker of neuroectodermal tissues and tumors, was present on all lines. These were also stained by the mouse monoclonal antibody HNK-1, which detects a carbohydrate epitope present on several glycoconjugates of the nervous system, including two glycoproteins, the myelin-associated glycoprotein and the neural cell-adhesion molecule (N-CAM), and an acidic glycolipid of the peripheral nervous system. The P61 monoclonal antibody, which reacts with a peptide moiety of N-CAM, and a rabbit antiserum, raised to purified mouse N-CAM and not recognizing the HNK-1-defined epitope, were also reactive. By contrast, all antibodies specific for hematopoietic cell surface antigens were totally negative. Besides these antigenic features, Ewing sarcoma cells are characterized by a specific t(11:22)(q24;q12) translocation also observed in neuroepithelioma, a neuroectodermal tumor, suggesting a possible evolutionary related origin. The recent finding that the human N-CAM gene is located at the vicinity of the breakpoint on chromosome 11 indicates that it might be involved in genetic rearrangements occurring in this region.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240310406
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...