[Calcium-binding Iba-1/AIF-1 protein in rat brain cells]

At present, calcium-binding Iba-1 protein is considered to be identical to AIF-1 protein and it is used as one of the selective microglia markers. However, the data on the cell populations capable of expressing Iba-1/AIF-1, are inconsistent. The aims of the present study were to identify rat brain cells expressing Iba-1 and to define their structural characteristics. The methods of immunocytochemistry and confocal laser microscopy were used. Iba-1 protein was detected only in microglial cells, macrophages of brain meninges, supraependymal macrophages, superficial and stromal cells of the choroid plexus--all the cells possessing phagocytotic function. Comparison of the data obtained with the results of other studies allows to suggest that not all of commonly used antibodies against Iba-1/AIF-1 demonstrate the same product. It can not be excluded, that it can be associated with the presence of alternative splicing of Iba-1 mRNA.