Abstract
The recently reported 85,000 MW membrane activation antigen, provisionally termed 7F7 antigen, is involved in the initiation of T-cell responses, in the binding of C3b-coated sheep erythrocytes to B cells and in the phorbol ester-induced aggregation of U937, suggesting that it represents a membrane molecule important for cell-cell adherence. Three new monoclonal antibodies were raised against the purified antigen and used to examine the expression of individual epitopes on cells of different lineage. All antibodies reacted with the purified membrane antigen on Western blots. Antibodies 7G2 and 7C6 reacted only weakly with activated T cells, although the 85,000 MW 7F7 antigen is recognized on T cells by antibodies 7F7 and 8B9. Whereas 7F7 and 8B9 inhibit the phorbol ester-induced aggregation of U937 and the attachment of phytohaemagglutinin (PHA)-activated T cells to fibroblasts, antibody 7G2 was without inhibitory effect. Four antibodies raised against the P3.58 glycoprotein, a melanoma-associated antigen with biochemical features similar to the 7F7 antigen were shown to react with the purified 7F7 antigen on Western blots. These four antibodies also failed to react with activated T cells. In addition, 7F7 bound to a L cell transfectant prepared with human chromosomal DNA which expressed the P3.58 antigen. The results indicate that the 7F7 antigen and the P3.58 melanoma antigen are identical, that some epitopes of this adherence molecule are differentially expressed on individual cell types and that one epitope, which is only weakly expressed on activated T cells, does not contribute to the role of the 7F7 antigen in some examples of cell-cell adherence.
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- Dustin M. L., Rothlein R., Bhan A. K., Dinarello C. A., Springer T. A. Induction by IL 1 and interferon-gamma: tissue distribution, biochemistry, and function of a natural adherence molecule (ICAM-1). J Immunol. 1986 Jul 1;137(1):245–254. [PubMed] [Google Scholar]
- Fraker P. J., Speck J. C., Jr Protein and cell membrane iodinations with a sparingly soluble chloroamide, 1,3,4,6-tetrachloro-3a,6a-diphrenylglycoluril. Biochem Biophys Res Commun. 1978 Feb 28;80(4):849–857. doi: 10.1016/0006-291x(78)91322-0. [DOI] [PubMed] [Google Scholar]
- Holzmann B., Bröcker E. B., Lehmann J. M., Ruiter D. J., Sorg C., Riethmüller G., Johnson J. P. Tumor progression in human malignant melanoma: five stages defined by their antigenic phenotypes. Int J Cancer. 1987 Apr 15;39(4):466–471. doi: 10.1002/ijc.2910390410. [DOI] [PubMed] [Google Scholar]
- Holzmann B., Johnson J. P., Kaudewitz P., Riethmüller G. In situ analysis of antigens on malignant and benign cells of the melanocyte lineage. Differential expression of two surface molecules, gp75 and p89. J Exp Med. 1985 Feb 1;161(2):366–377. doi: 10.1084/jem.161.2.366. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Holzmann B., Lehmann J. M., Ziegler-Heitbrock H. W., Funke I., Riethmüller G., Johnson J. P. Glycoprotein P3.58, associated with tumor progression in malignant melanoma, is a novel leukocyte activation antigen. Int J Cancer. 1988 Apr 15;41(4):542–547. doi: 10.1002/ijc.2910410412. [DOI] [PubMed] [Google Scholar]
- Schulz T. F., Mitterer M., Vogetseder W., Böck G., Myones B. L., Dierich M. P. Identification and characterization of a novel membrane activation antigen with wide cellular distribution. Eur J Immunol. 1988 Jan;18(1):7–11. doi: 10.1002/eji.1830180103. [DOI] [PubMed] [Google Scholar]
- Schulz T. F., Scheiner O., Alsenz J., Lambris J. D., Dierich M. P. Use of monoclonal antibodies against factor H to investigate the role of a membrane-associated protein antigenically related to H in C3b-receptor function. J Immunol. 1984 Jan;132(1):392–398. [PubMed] [Google Scholar]
- Stein H., Gerdes J., Schwab U., Lemke H., Mason D. Y., Ziegler A., Schienle W., Diehl V. Identification of Hodgkin and Sternberg-reed cells as a unique cell type derived from a newly-detected small-cell population. Int J Cancer. 1982 Oct 15;30(4):445–459. doi: 10.1002/ijc.2910300411. [DOI] [PubMed] [Google Scholar]
- Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]



