Binding motifs of CBP2 a potential cell surface target for carcinoma cells.
Previously we have shown (Hebert et al. [1999] J. Cell Biochem. 73:248-258) that among many cell lines the CBP2 gene product, Hsp47, eludes its retention receptor, erd2P, resulting in the appearance of Hsp47 on the cell surface associated with the tetraspanin protein CD9. Since Hsp47 possesses a highly restricted binding cleft, random peptide display libraries were used to characterize peptides binding to Hsp47 and then to target this protein on carcinoma cell lines in vitro. Comparison of the clones obtained from panning revealed little specific homology based on sequence alone. To determine whether carcinoma cells expressing Hsp47 could selectively take up the selected bacteriophages, traditional immunofluorescence and confocal microscopy were employed. These studies revealed that phage-displaying Hsp47 binding peptides bound to cell lines expressing Hsp47 and that the peptides were rapidly taken up to a location coincident with Hsp47 staining. These observations were confirmed by cytometric analyses. These data indicate that CBP2 product may provide a molecular target for chemotherapy and/or imaging of malignancies.
Sauk
J J
JJ
Department of Pathology, University of Maryland, Baltimore, Maryland 21201, USA. jjd001@dental.umaryland.edu
Coletta
R D
RD
Norris
K
K
Hebert
C
C
D020816:Amino Acid Motifs / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D006023:Glycoproteins; D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000628:therapy; D019151:Peptide Library; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D017931:DNA Primers; D006023:Glycoproteins; D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D019151:Peptide Library; C494660:SERPINH1 protein, human; C046289:colligin; D003094:Collagen