title: Allograft inflammatory factor-1 defines a distinct subset of infiltrating macrophages/microglial cells in rat and human gliomas.
abstract: Allograft inflammatory factor-1 (AIF-1) is a Ca2+-binding peptide that constitutes a potential modulator of macrophage activation and function during the immune response of the brain. Peptides termed microglia response factor-1 or ionized calcium-binding adaptor molecule- have been reported to be identical with AIF-1. We have investigated the expression of AIF-1 in the rat C6 glioblastoma and 9L gliosarcoma tumor models and additionally assessed AIF- expression in a diverse range of human astrocytomas by immunohistochemistry. AIF-1 was expressed by activated microglial cells and a subset of infiltrating macrophages in areas of infiltrative tumor growth and in compact tumor areas in both rat and human gliomas. Double-labeling experiments in rats and humans characterized the nature and the functional status of AIF-1+ cells. AIF-1 expression was detected in cells expressing major histocompatibility complex class II molecules and in a subset of activated macrophages/microglial cells. All MRP-8+ cells coexpressed AIF-1. In humans, there was a strong correlation of AIF-1-expressing activated macrophages/microglial cells with tumor malignancy (P < 0.0001). These results suggest that AIF-1 defines a distinct subset of tumor-associated activated macrophages/ microglial cells.
authors.affiliation: Institute of Brain Research, University of Tuebingen, Germany. hirnforschung@uni-tuebingen.de
authors.forename: M H
authors.initials: MH
authors.lastname: Deininger
authors.forename: K
authors.initials: K
authors.lastname: Seid
authors.forename: S
authors.initials: S
authors.lastname: Engel
authors.forename: R
authors.initials: R
authors.lastname: Meyermann
authors.forename: H J
authors.initials: HJ
authors.lastname: Schluesener
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D001254:Astrocytoma / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins; D004195:Disease Models, Animal; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005909:Glioblastoma / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D005910:Glioma / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008840:Microfilament Proteins; D017628:Microglia / Q000378:metabolism* / Q000473:pathology*; D008875:Middle Aged; D008969:Molecular Sequence Data; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000473:pathology
chemical_list: C112986:AIF1 protein, human; C100745:Aif1 protein, rat; D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D005904:Glial Fibrillary Acidic Protein; D008840:Microfilament Proteins