Top-down analysis of low mass proteins in exosomes shed by murine myeloid-derived suppressor cells.
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 %.
University of Maryland, College Park, MD. 20742. United States.
Lucía
L
Geis-Asteggiante
University of Maryland, College Park, MD. 20742. United States.
Avantika
A
Dhabaria
Georgetown University Medical Center, Washington, D.C. 20057. United States.
Nathan
N
Edwards
University of Maryland Baltimore County, Baltimore, MD. 21250. United States.
Suzanne
S
Ostrand-Rosenberg
University of Maryland, College Park, MD. 20742. United States.
Catherine
C
Fenselau
cytokines; exosomes; histones; post-translational modifications; top-down proteomics