Abstract
Cystic fibrosis (CF) is characterized by an abnormality in cAMP-regulated chloride transport that results from a primary defect in the protein product of the CF gene, the CF transmembrane conductance regulator (CFTR). In this report, antibodies against CFTR peptides were used to localize the CFTR protein in human pancreas. An affinity purified antibody (alpha-1468) raised against a synthetic CFTR peptide identified a 155-170-kD protein on immunoblot. Cytochemical studies with alpha-1468 localized CFTR to small branching, tubular structures. The same structures were recognized by two other antibodies raised against different regions of the CFTR molecule. To identify the cells being stained, double-label immunofluorescence studies were performed using alpha-1468 and a monoclonal antibody which stains pancreatic centroacinar and intralobular duct cells. Both antibodies localized to the same population of cells, with alpha-1468 being confined to the apical domain of these cells. No conclusive staining of acinar cells was evident. These findings suggest that proximal duct epithelial cells play a key role in the early events leading to pancreatic insufficiency in CF, and imply that apical chloride transport by these cells is essential for normal pancreatic secretory function.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Cheng S. H., Gregory R. J., Marshall J., Paul S., Souza D. W., White G. A., O'Riordan C. R., Smith A. E. Defective intracellular transport and processing of CFTR is the molecular basis of most cystic fibrosis. Cell. 1990 Nov 16;63(4):827–834. doi: 10.1016/0092-8674(90)90148-8. [DOI] [PubMed] [Google Scholar]
- Drumm M. L., Pope H. A., Cliff W. H., Rommens J. M., Marvin S. A., Tsui L. C., Collins F. S., Frizzell R. A., Wilson J. M. Correction of the cystic fibrosis defect in vitro by retrovirus-mediated gene transfer. Cell. 1990 Sep 21;62(6):1227–1233. doi: 10.1016/0092-8674(90)90398-x. [DOI] [PubMed] [Google Scholar]
- Gaskin K. J., Durie P. R., Corey M., Wei P., Forstner G. G. Evidence for a primary defect of pancreatic HCO3-secretion in cystic fibrosis. Pediatr Res. 1982 Jul;16(7):554–557. doi: 10.1203/00006450-198207000-00012. [DOI] [PubMed] [Google Scholar]
- Gasser K. W., DiDomenico J., Hopfer U. Secretagogues activate chloride transport pathways in pancreatic zymogen granules. Am J Physiol. 1988 Jan;254(1 Pt 1):G93–G99. doi: 10.1152/ajpgi.1988.254.1.G93. [DOI] [PubMed] [Google Scholar]
- Gershoni J. M., Palade G. E. Protein blotting: principles and applications. Anal Biochem. 1983 May;131(1):1–15. doi: 10.1016/0003-2697(83)90128-8. [DOI] [PubMed] [Google Scholar]
- Gray M. A., Greenwell J. R., Argent B. E. Secretin-regulated chloride channel on the apical plasma membrane of pancreatic duct cells. J Membr Biol. 1988 Oct;105(2):131–142. doi: 10.1007/BF02009166. [DOI] [PubMed] [Google Scholar]
- Gray M. A., Harris A., Coleman L., Greenwell J. R., Argent B. E. Two types of chloride channel on duct cells cultured from human fetal pancreas. Am J Physiol. 1989 Aug;257(2 Pt 1):C240–C251. doi: 10.1152/ajpcell.1989.257.2.C240. [DOI] [PubMed] [Google Scholar]
- Gregory R. J., Cheng S. H., Rich D. P., Marshall J., Paul S., Hehir K., Ostedgaard L., Klinger K. W., Welsh M. J., Smith A. E. Expression and characterization of the cystic fibrosis transmembrane conductance regulator. Nature. 1990 Sep 27;347(6291):382–386. doi: 10.1038/347382a0. [DOI] [PubMed] [Google Scholar]
- Kasai H., Augustine G. J. Cytosolic Ca2+ gradients triggering unidirectional fluid secretion from exocrine pancreas. Nature. 1990 Dec 20;348(6303):735–738. doi: 10.1038/348735a0. [DOI] [PubMed] [Google Scholar]
- Kerem B., Rommens J. M., Buchanan J. A., Markiewicz D., Cox T. K., Chakravarti A., Buchwald M., Tsui L. C. Identification of the cystic fibrosis gene: genetic analysis. Science. 1989 Sep 8;245(4922):1073–1080. doi: 10.1126/science.2570460. [DOI] [PubMed] [Google Scholar]
- Kopelman H., Durie P., Gaskin K., Weizman Z., Forstner G. Pancreatic fluid secretion and protein hyperconcentration in cystic fibrosis. N Engl J Med. 1985 Feb 7;312(6):329–334. doi: 10.1056/NEJM198502073120601. [DOI] [PubMed] [Google Scholar]
- Kopelman H., Forstner G., Durie P., Corey M. Origins of chloride and bicarbonate secretory defects in the cystic fibrosis pancreas, as suggested by pancreatic function studies on control and CF subjects with preserved pancreatic function. Clin Invest Med. 1989 Jun;12(3):207–211. [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Oppenheimer E. H., Esterly J. R. Pathology of cystic fibrosis review of the literature and comparison with 146 autopsied cases. Perspect Pediatr Pathol. 1975;2:241–278. [PubMed] [Google Scholar]
- Quinton P. M. Cystic fibrosis: a disease in electrolyte transport. FASEB J. 1990 Jul;4(10):2709–2717. doi: 10.1096/fasebj.4.10.2197151. [DOI] [PubMed] [Google Scholar]
- Rich D. P., Anderson M. P., Gregory R. J., Cheng S. H., Paul S., Jefferson D. M., McCann J. D., Klinger K. W., Smith A. E., Welsh M. J. Expression of cystic fibrosis transmembrane conductance regulator corrects defective chloride channel regulation in cystic fibrosis airway epithelial cells. Nature. 1990 Sep 27;347(6291):358–363. doi: 10.1038/347358a0. [DOI] [PubMed] [Google Scholar]
- Riordan J. R., Rommens J. M., Kerem B., Alon N., Rozmahel R., Grzelczak Z., Zielenski J., Lok S., Plavsic N., Chou J. L. Identification of the cystic fibrosis gene: cloning and characterization of complementary DNA. Science. 1989 Sep 8;245(4922):1066–1073. doi: 10.1126/science.2475911. [DOI] [PubMed] [Google Scholar]
- Rommens J. M., Iannuzzi M. C., Kerem B., Drumm M. L., Melmer G., Dean M., Rozmahel R., Cole J. L., Kennedy D., Hidaka N. Identification of the cystic fibrosis gene: chromosome walking and jumping. Science. 1989 Sep 8;245(4922):1059–1065. doi: 10.1126/science.2772657. [DOI] [PubMed] [Google Scholar]
- Welsh M. J. Abnormal regulation of ion channels in cystic fibrosis epithelia. FASEB J. 1990 Jul;4(10):2718–2725. doi: 10.1096/fasebj.4.10.1695593. [DOI] [PubMed] [Google Scholar]