I'm trying to distinguish exosomes collected from human plasma samples by the cell types (e.g. hepatocytes, monocytes, endothelial cells, etc.) that may have produced them. I've been trying to find some sort of cell-specific exosomal protein or RNA marker, but I haven't been able to find anything like that in the literature, only potential markers for various sorts of cancers.

Does anyone know of a specific exosomal marker that fits my needs? I'm especially interested in hepatocyte exosomes, and exosomes from astrocytes and microglia.