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Gene regulation in macrophages from irradiated tumors

ABSTRACT: Tumors engender an environment dominated by M2 differentiated tumor macrophages that support tumor invasion, metastases and escape from immune control. In this study, we demonstrate that following radiation therapy of tumors in mice there is an influx of tumor macrophages that polarize towards wound repair and immune suppression. To investigate changes in the phenotype of tumor macrophages following radiation therapy, we FACS sorted tumor macrophages from Panc02 tumors. We have previously shown that we can distinguish mature tumor macrophages from immature myeloid and MDSC populations by expression of Gr1 and IA (MHC class II). To isolate these sub-populations, we first gated CD11b+ cells in the untreated or irradiated tumors, then sorted the CD11b+IA+ macrophage population and the CD11b+Gr1hi MDSC population. Cytospins of the sorted populations demonstrates that the CD11b+Gr1hi MDSC predominantly have a granulocyte morphology and the CD11b+IA+ cells have a macrophage morphology in both the untreated and irradiated tumors. RNA was purified from CD11b+IA+ macrophages from untreated or irradiated tumors 1 day or 7 days following radiation therapy and Gene Expression Microarray analysis was performed.

ORGANISM(S): Mus musculus

PROVIDER: GSE34206 | GEO | 2011/12/07

SECONDARY ACCESSION(S): PRJNA149669

REPOSITORIES: GEO

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Gene regulation in macrophages from irradiated tumors

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