A New Double Labelling Immunofluorescence Technique for the Determination of Proliferation of Human Astrocytes in Culture

We describe a method that can positively identify proliferating human astrocytes in culture. The procedure is an indirect double immunofluorescence staining technique that uses bromodeoxyuridine together with specific antibodies directed against it and glial fibrillary acidic protein. The method is simple, rapid, reproducible, and promises to decrease many of the limitations inherent in other previously used methods. Using this technique, we observed that mitosis occurred in 57 and 11% of human astrocytes that have been in culture for 11 days and 16 weeks, respectively.