In humans, the immunoglobulin super family containing leucine-rich repeat (ISLR) protein is encoded by the ISLR gene. Current RNA-seq studies show that the protein is highly expressed in the endometrium and ovary and shows expression among 25 other tissues. The protein is seen localized in the cytoplasm, plasma membrane, extracellular exosome, and platelet alpha granule lumen. Furthermore, the protein is known to play a role in platelet degranulation, cell adhesion, and response to elevated platelet cytosolic Ca2+.