Abstract:
:It is not rare that controversial indications about the presence or the expression level of multidrug-resistant (MDR) proteins come out from different laboratories upon examination of identical tumor specimens. Distinct aspects, including the use of weakly discriminating monoclonal antibodies (MAbs) and/or unsuitable techniques and procedures, contribute in generating differences in the MDR phenotype evaluation of cancer cells. In this regard we describe here an innovative immunohistochemical approach for the determination of P-glycoprotein expression in cells and tissues. The method is based on the ability of phage-displayed peptides to mimic antibody epitopes. For this purpose we utilized the phage clone #55, which was affinity-purified from a phage-displayed random-peptide library using the MAb MM4.17 (specific for MDR1-P-glycoprotein) as previously described. This clone has been chosen since it clearly and undoubtedly reacts with its cognate MAb, as was determined by ELISA and dot blot tests. Inhibition of the MAb MM4.17 binding to MDR1-P-glycoprotein-expressing cells could be performed by adding a calibrated concentration of phage clone #55 particles, which mimic MDR1-P-glycoprotein antigen. This methodology can eliminate misleading interpretations concerning the presence and expression level of MDR1-P-glycoprotein and might well contribute in routine clinical determinations of MDR in tumor specimens, thus contributing to our understanding of the basis of the mechanisms of tumor cell resistance to drugs.
journal_name
Biol Chemjournal_title
Biological chemistryauthors
Poloni F,Castagna M,Felici F,Cianfriglia Mdoi
10.1515/bchm.1997.378.6.503subject
Has Abstractpub_date
1997-06-01 00:00:00pages
503-7issue
6eissn
1431-6730issn
1437-4315journal_volume
378pub_type
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journal_title:Biological chemistry
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journal_title:Biological chemistry
pub_type: 杂志文章,评审
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更新日期:1996-07-01 00:00:00
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pub_type: 杂志文章
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