Summary
Angiotensin I-converting enzyme is responsible for the activation of angiotensin I and the inactivation of bradykinin. It has been localized by immunofluorescence on the endothelium of a variety of tissues and has been considered to be a specific marker for endothelial cells in culture. The present paper demonstrates, by immunofluorescence, the presence of angiotensin I-converting enzyme in monolayer cultures of fibroblasts derived from adult rat lung, bovine calf pulmonary artery, and human foreskin (CF-3 cells). Fluorescent localization of angiotensin I-converting enzyme was observed over the cytoplasm of adult rat lung and bovine calf pulmonary artery fibroblasts and as distinct areas overlying the nuclei of human foreskin fibroblasts. Determination of angiotensin I-converting enzyme activity by fluorimetric assay in parallel studies confirmed the presence of angiotensin I-converting enzyme activity in cultured fibroblasts. Immunofluorescent studies with antibody to Factor VIII demonstrated the presence of Factor VIII on cultured endothelial cells but not on fibroblasts. These results indicate that angiotensin I-converting enzyme is not confined to endothelial cells, and thus may not serve as a specific marker for endothelial cells in culture. Factor VIII may be a more specific marker for these cells.
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Johnson, A. R.; Erdos, E. G. Metabolism of vasoactive peptides by human endothelial cells in culture: angiotensin-I-converting enzyme (kininase II) and angiotensinase. J. Clin. Invest. 59: 684–695; 1977.
Soffer, R. L. Angiotensin-converting enzyme and the regulation of vasoactive peptides. Ann. Rev. Biochem. 45: 73–94; 1976.
Ryan, U. S.; Ryan, J. W.; Whitaker, C.; Chiu, A. Localization of angiotensin converting enzyme (kininase II) II. Immunocytochemistry and immunofluorescence. Tissue Cell 8: 125–145; 1976.
Smith, U.; Ryan, J. W. Electron microscopy of endothelial and epithelial components of the lungs: correlations of structure and function. Fed. Proc. 32: 1957–1966; 1973.
Caldwell, P. R. B.; Seegal, B. C.; Hsu, K. C. Angiotensin converting enzyme: vascular endothelial localization. Science 191: 1050–1051; 1976.
Wigger, H. J.; Stalcup, S. A. Distribution and development of angiotensin converting enzyme in the fetal and newborn rabbit: an immunofluorescence study. Lab. Invest. 38: 581–585; 1978.
Dell’Orco, R. T.; Martin, T. J.; Douglas, W. H. J. Cyclic AMP and serum arrest of the mitotic activity of human diploid fibroblasts. In Vitro 13: 55–62; 1977.
Douglas, W. H. J.; Kaighn, M. E. Clonal isolation of differentiated rat lung cells. In Vitro 10: 230–235; 1974.
Kruse, P. E., Jr.; Patterson, M. K., Jr. eds. Tissue culture methods and applications. New York: Academic Press; 1973: 72–81.
Lanzillo, J. J.; Fanburg, B. L. Membrane-bound angiotensin-converting enzyme from rat lung. J. Biol. Chem. 249: 2312–2318; 1974.
Lanzillo, J. J.; Fanburg, B. L. Angiotensin I converting enzyme from human plasma. Biochemistry 16: 5491–5494; 1977.
Polsky-Cynkin, R.; Fanburg, B. L. Immunochemical comparison of angiotensin-I-converting enzymes from different rat organs. Int. J. Biochem. 10: 669–674; 1979.
Weir, D. M. ed. Handbook of experimental immunology, 2nd ed. Oxford: Blackwell; 1973: 7.1–7.11, 8.1–8.11.
Grabar, P.; Williams, C. A. Méthode permettant l’etude conjugée des proprietés électrophorétiques et immunochemiques d’un mélange de protéins. Application an serum sanguin. Biochim. Biophys. Acta 10: 193–194; 1953.
Friedland, J.; Silverstein, E. A sensitive fluorimetric assay for serum angiotensin converting enzyme. Am. J. Clin. Pathol. 66: 416–424; 1976.
Lowry, O. H.; Rosebrough, N. J.; Farr, L.; Randall, R. J. Protein measurement with the folin phenol reagent. J. Biol. Chem. 193: 265–275; 1951.
Hill, B. T.; Whatley, S. A simple, rapid microassay for DNA. FEBS Lett. 56: 20–23; 1975.
Hoyer, L. W.; DeLos Santos, R. P.; Hoyer, J. R. Antihemophilic factor antigen localization in endothelial cells by immunofluorescent microscopy. J. Clin. Invest. 52: 2737–2744; 1973.
Silverstein, S.; Friedland, J.; Setton, C. Angiotensin-converting enzyme in macrophages and Freund’s adjuvant granuloma. Isr. J. Med. Sci. 14: 314–318; 1978.
Rubin, D. B.; Dobbs, L. G. Angiotensin converting enzyme activity in fibroblasts and endothelial cells. J. Cell Biol. 83: 98a; 1979.
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Wendy Baur and Ms. Jane Aghajanian for expert assistance in the preparation of the cell cultures.
This work was supported by Research Grant HL 14456 and Training Grant HL 07053 from the National Institutes of Health, Bethesda, MD.
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Weinberg, K.S., Douglas, W.H.J., MacNamee, D.R. et al. Angiotensin I-converting enzyme localization on cultured fibroblasts by immunofluorescence. In Vitro 18, 400–406 (1982). https://doi.org/10.1007/BF02796341
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DOI: https://doi.org/10.1007/BF02796341