Prepending expand/collapse icon to text on a Datagridview winforms cell

Question

I use a Winforms Datagridview to display hierarchical data, inserting indented rows of a deeper level when the user double-clicks a parent row. Subsequent levels are indented, so expand/collapse icons on a specific column is not an option. My current solution is to display a boring plus or minus character before the text. Is there a way to prepend a symbol font at the begining of the indented cell text?