fibronectin (fN) is a glycoprotein with 5-9% carbohydrates present as N- and O-linked oligosaccharides. It belongs to the ligand glycoprotein family. The fN gene is localized to human chromosome 2q35. fN exists as two major isoforms plasma-based soluble and extracellular matrix (ECM)-based insoluble form. fN is a multidomain protein and comprises repeats of fNI fNII and fNIII repeats. It also has fibrin-binding sites and exists as a dimer. Alternative splicing of the fN1 gene leads to the generation of many isoforms. Recombinant human fibronectin is expressed in human 293 cells as a glycoprotein with a calculated molecular mass of 259.5 kDa. This protein is manufactured in human cells using an all-human production system with no serum. The human cells expression system allows human-like glycosylation and folding and often supports better stability of the protein in culture.