Chromogranin A Peptide-Specific Antisera and High-Performance Size Exclusion Chromatography Demonstrate Amino-Terminal and Carboxy-Terminal Fragments of the Native Molecule in Human Cell Lines

D. W. Brandt, D. W. Burton, R. Hogue-Angeletti, L. J. Deftos

Research output: Contribution to journalArticle

15 Scopus citations


We have studied the pattern of amino-terminal and carboxy-terminal protein processing of chromogranin A (CgA) in five human cell lines, four derived from lung cancers: NCI-H478, NCI-H1011, NCI-H727, and BEN; and one derived from human medullary thyroid carcinoma: TT. This was accomplished by fractionation of cell extracts by high-performance size exclusion chromatography (HPSEC) and measurement of CgA in the fractions by radioimmunoassay (RIA). Three RIA's were used, one specific for the amino-terminus of CgA, one specific for the carboxy-terminal region, and a monoclonal antibody-based assay that recognizes only the native CgA molecule. We demonstrated the presence of different amino- and carboxy-terminal immunoreactive species of CgA in the different cell lines. The amino-terminal assay demonstrated distinct low-molecular-size species in the NCI-H478 and NCI-H1011 cell lines, and a similar peak in the TT cells. The amino-terminal assay did not recognize any distinct species in BEN and NCI-H727 cell lines. The carboxy-regional assay demonstrated distinct low-molecular-size species in the NCI-H478 and NCI-H101 cell lines and high-molecular-size species in the NCI-H727 and BEN cells. Our studies demonstrate with region-specific RIA's the presence of both amino- and carboxy- forms of CgA in human cells that secrete this protein. These results provide direct evidence that CgA-producing cells produce, probably through endoproteolytic processing of the native molecule, amino- and carboxy-terminal forms of the protein.

Original languageEnglish (US)
Pages (from-to)316-320
Number of pages5
JournalProceedings of the Society for Experimental Biology and Medicine
Issue number4
StatePublished - Apr 1994


ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

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