An immortalized mouse MD cell line named MDgeo was generated for in vitro cell biology studies by following a commonly used workflow, as illustrated in Figure 4A. Primary cultures of freshly isolated and sorted MD cells from MD-GFP kidneys were transfected with LentiSV40 tsA58 virus for temperature-sensitive proliferation (at 33°C) or differentiation (at 37°C) in the presence of NGF. This evidence concerns the gene NGF and Menkes disease.