For instance, Gangadaran and colleagues functionalized the surface of MSC-EVs with a peptide that targets interleukin-4 receptor (IL-4R), which is upregulated in various types of tumours, using a membrane phospholipid-based linker composed of dioleylphosphatidylethanolamine (DOPE), methoxy PEG and succinyl-N-hydroxy-succinimidyl (NHS) ester. The gene discussed is IL4R; the disease is neoplasm.