Allograft inflammatory factor-1 defines a distinct subset of infiltrating macrophages/microglial cells in rat and human gliomas

Acta Neuropathol. 2000 Dec;100(6):673-80. doi: 10.1007/s004010000233.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Astrocytoma / metabolism
  • Astrocytoma / pathology
  • Astrocytoma / physiopathology
  • Biomarkers, Tumor / metabolism*
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism*
  • DNA-Binding Proteins
  • Disease Models, Animal
  • Female
  • Glial Fibrillary Acidic Protein / metabolism
  • Glioblastoma / metabolism
  • Glioblastoma / pathology
  • Glioblastoma / physiopathology
  • Glioma / metabolism*
  • Glioma / pathology*
  • Glioma / physiopathology
  • Humans
  • Macrophages / metabolism*
  • Macrophages / pathology*
  • Male
  • Microfilament Proteins
  • Microglia / metabolism*
  • Microglia / pathology*
  • Middle Aged
  • Molecular Sequence Data
  • Rats
  • Sequence Homology, Nucleic Acid
  • Tumor Cells, Cultured / metabolism
  • Tumor Cells, Cultured / pathology


  • AIF1 protein, human
  • Aif1 protein, rat
  • Biomarkers, Tumor
  • Calcium-Binding Proteins
  • DNA-Binding Proteins
  • Glial Fibrillary Acidic Protein
  • Microfilament Proteins