Proteomic identification of an MHC-binding peptidome from pancreas and breast cancer cell lines
| Autor: | Kwasi Antwi, Paul D. Hanavan, Cheryl E. Myers, Eric J. Thompson, Yvette W. Ruiz, Douglas F. Lake |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Proteomics
Proteome Cell Survival Immunology Cell Peptide Breast Neoplasms Human leukocyte antigen Biology Major histocompatibility complex Citric Acid Immune system Tandem Mass Spectrometry Cell Line Tumor MHC class I Papain medicine Humans Molecular Biology Chromatography High Pressure Liquid chemistry.chemical_classification Histocompatibility Antigens Class I Anticoagulants Hydrogen-Ion Concentration Molecular biology Peptide Fragments Amino acid Pancreatic Neoplasms medicine.anatomical_structure chemistry Cell culture biology.protein Female |
| Zdroj: | Molecular immunology. 46(15) |
| ISSN: | 1872-9142 |
| Popis: | Peptides bound to cell surface MHC class I molecules allow the immune system to recognize intracellular pathogens and tumor-derived peptides. Our goal was to learn what the immune system "sees" on the surfaces of tumor cells by acid-eluting peptides from HLA molecules for extended time periods. We determined how long peptides would continue to elute over time from a pancreatic tumor cell line, Panc-1, and a breast cancer cell line, MCF-7, at pH 3.0 in citrate buffer while monitoring viability. Both cell lines demonstrated greater than 90% viability after 25min at pH 3.0. Panc-1 remained >90% intact after 45min at pH 3.0. Acid eluted peptide sequences were identified using LC-MS/MS and searching the NCBI refseq database. The total number of peptides eluted peaked between 40 and 45min for Panc-1, but continued to increase over time from MCF-7. A total of 131 peptides were identified from Panc-1 while 101 peptides were identified from MCF-7 elutions. Two classes of peptides were eluted: (1) 8-10 amino acid peptides fitting the HLA-binding motifs of each cell line, and (2) peptides longer than 10 amino acids containing HLA-binding motifs of each cell line. W6/32 antibody affinity purification of intact MHC molecules after papain cleavage of MHC class I from tumor cell surfaces also indicated that peptides longer than 10 amino acids bind to class I proteins. A peptide-MHC-refolding assay further substantiated the binding of longer peptides to HLA-A*0201. Our findings provide sequences and gene names of peptides presented by MHC class I molecules from common pancreas and breast cancer cell lines. We utilized a novel refolding assay to demonstrate that peptides longer than the canonical 8-10 amino acids commonly bind in MHC class I cell surface molecules. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect