HAPLN2 and hydrops fetalis: The gene expression of the following ECM component proteins was up-regulated between HF bulge stem cells and the differentiated epidermal cells: metallopeptidase, cingulin, type IV collagen α3 and α4 chains, fibulin-1, hyaluronan and proteoglycan link protein 2 (HAPLN2), integrin β8 [96], tenascin-C, α chains of type VI and type XVIII collagens, biglycan, syndecan 1, and others [94,95].