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K Gatter

Publications and source records attributed to K Gatter.

60 records · Page 4Linked to original sources
PubMed1987

Distribution and epitope analysis of the cell membrane glycoprotein (HPCA-1) associated with human hemopoietic progenitor cells.

Monoclonal antibodies My10, BI.3C5, 12.8, and ICH3 identify a monomeric cell surface glycoprotein (HPCA-1) of 100-120 kD, which is selectively expressed on human hemopoietic progenitor cells. Other tissues are nonreactive with the exception of capillary endothelia and basement membrane in some sites. In addition, the antigen can be detected on cell lines that exhibit characteristics associated with early T cell precursors. HPCA-1 is therefore associated with myeloid, B, and T lineage precursors. Sequential immunoprecipitation and Western blotting studies demonstrate that BI.3C5, ICH3, My10, and an antibody directed against endothelial cells, 188.27, all react with the same glycoprotein species, although the epitopes involved may be distinct. The epitope recognized by BI.3C5 is sialic acid dependent, whereas that recognized by ICH3 is not. The My10 epitope has partial sensitivity to neuraminidase. Competitive/additive binding experiments suggest that these epitopes, although probably distinct, may be closely associated.

Antibodies, Monoclonal↗
PubMed1985

Use of freeze-dried paraffin-embedded sections for immunohistologic staining with monoclonal antibodies.

Most diagnostically valuable monoclonal antibodies recognize antigens that do not survive conventional tissue processing. The use of frozen tissue sections for immunohistologic studies overcomes this obstacle but introduces a number of practical problems, e.g., the necessity to store material in the frozen state, poor morphologic preservation, etc. In the present paper we report that antigenic denaturation during conventional tissue processing appears to occur during exposure to aldehyde-containing fixatives and to alcohol but not as a result of heating or exposure to melted paraffin wax. In consequence, we have developed a technique by which tissue is freeze-dried and then embedded directly in paraffin wax. All but one of the 40 monoclonal antibodies investigated stained the freeze-dried paraffin sections with an intensity equal to or greater than that observed on frozen sections. There was less diffusion artifact and less background staining than in cryostat sections, and cellular morphology was better preserved. One of the most important advantages of this new method is that antigens in freeze-dried paraffin-embedded tissue are stable, and tissue blocks may be handled in the same manner as conventional paraffin blocks. An additional finding was that, once the tissue has been freeze-dried, paraffin embedded, and sectioned, the antigens it contains are resistant to fixatives (e.g., formol, formol sublimate, alcohols) which would very rapidly cause their destruction in frozen sections.

Antibodies, Monoclonal↗
PubMed1985

The expression of the Hodgkin's disease associated antigen Ki-1 in reactive and neoplastic lymphoid tissue: evidence that Reed-Sternberg cells and histiocytic malignancies are derived from activated lymphoid cells.

Ki-1 is a monoclonal antibody (raised against a Hodgkin's disease-derived cell line) that, in biopsy tissue affected by Hodgkin's disease, reacts selectively with Reed-Sternberg cells. The expression of Ki-1 antigen has been analyzed by immunocytochemical techniques in a wide range of human tissue and cell samples, including fetal tissue, malignant lymphomas (290 cases), and mitogen- and virus-transformed peripheral blood lymphocytes. The antigen was detectable on a variable proportion of cells in all cases of lymphomatoid papulosis and angio-immunoblastic lymphadenopathy and in 28% of the cases of peripheral T cell lymphomas (including lympho-epithelioid lymphomas). It was also expressed (more strongly) on tumor cells in 45 cases of diffuse large-cell lymphoma, most of which had originally been diagnosed as malignant histiocytosis or anaplastic carcinoma, because of their bizarre morphology. However, all of these cases lacked macrophage and epithelial antigens. Thirty-five cases expressed T cell-related antigens (associated in nine cases with the coexpression of B cell-related antigens), seven bore B cell-related antigens alone, and three were devoid of T and B cell markers. DNA hybridization with a JH specific probe showed a germline configuration in 11 cases of T cell phenotype, in two cases lacking T and B cell antigens, and in one case of mixed T/B phenotype, while rearrangement was found in two cases of clear B cell type and in one mixed T/B case. Expression of the Ki-1 antigen could be induced, together with interleukin 2 (IL 2) receptor, on normal lymphoid cells of both T and B cell type by exposure to phytohemagglutinin, human T leukemia viruses, Epstein-Barr virus, or Staphylococcus aureus. The results obtained indicate that Ki-1 antigen is an inducible lymphoid-associated molecule that identifies a group of hitherto poorly characterized normal and neoplastic large lymphoid cells. Tumors comprised solely of these cells show both morphological and immunological similarities to the neoplastic cells in Hodgkin's disease. This suggests that both disorders represent the neoplastic proliferation of activated lymphoid cells of either T cell or, less commonly, B cell origin. Disorders in which only a minority of cells express Ki-1 antigen (lymphomatoid papulosis, angio-immunoblastic lymphadenopathy, and certain T cell lymphomas) probably represent lesions in which only some of the abnormal cells have transformed into an "activation state." In direct support of this view is the finding that the Ki-1 expression in these lesions is accompanied by the expression of HLA-DR and IL 2 receptors.

Adolescent↗