ESM1 is a secreted dermatan sulfate proteoglycan which is predominantly expressed in the endothelial cells in human lung and kidney tissues. Expression of ESM1 is regulated by cytokines. ESM1 may have a role in lung endothelial cell-leukocyte interactions. The transcript contains multiple polyadenylation and mRNA instability signals. Two transcript variants encoding different isoforms have been found for this gene.