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Top-down analysis of low mass proteins in exosomes shed by murine myeloid-derived suppressor cells.

ABSTRACT: Top-down analysis is reported for a portion of the protein cargo of exosomes shed by myeloid-derived suppressor cells that participate in intracellular signaling in the tumor microenvironment. Instrument mass resolution limited the study to proteins of molecular masses below 30 kDa. A two-step fractionation strategy was used, including open tubular gel electrophoresis and C3 reverse phase high performance liquid chromatography. Twenty-one unique proteins were identified among more than 200 proteoforms, and comprising primarily two functionally important protein families: the S100 proinflammatory mediators and an abundance of histones. Fifty-six percent of the total protein in these exosomes was determined to comprise histones, of which H2B variants contribute 42 %.

SUBMITTER: Geis-Asteggiante L

PROVIDER: S-EPMC4413943 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Top-down analysis of low mass proteins in exosomes shed by murine myeloid-derived suppressor cells.

Geis-Asteggiante Lucía L Dhabaria Avantika A Edwards Nathan N Ostrand-Rosenberg Suzanne S Fenselau Catherine C

International journal of mass spectrometry 20150201

Top-down analysis is reported for a portion of the protein cargo of exosomes shed by myeloid-derived suppressor cells that participate in intracellular signaling in the tumor microenvironment. Instrument mass resolution limited the study to proteins of molecular masses below 30 kDa. A two-step fractionation strategy was used, including open tubular gel electrophoresis and C3 reverse phase high performance liquid chromatography. Twenty-one unique proteins were identified among more than 200 prote ...[more]

PMID: 25937807

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