Folliculostellate cells of pituitary gland, light micrograph. In addition to hormone-secreting cells, the anterior lobe of the pituitary contains a cell type, folliculo-stellate cells, of unclear function, but probably supportive. These cells appear in all species and are characterized by vimentin-rich filaments. This image shows folliculo-stellate cells in a rabbit pituitary stained with an immunohistochemistry (IHC) technique to detect vimentin.