Four isozymes of nicotinamide-adenine dinucleotide phosphate (NADP) linked isocitric dehydrogenase can be demonstrated by starch gel electrophoresis in normal human epidermis. In the lesions of psoriasis and in basal cell carcinoma only two of these isozymes can be demonstrated. With healing of the psoriatic lesion the two missing isozymes return.
Fukui K, Halprin KM, Ohkawara A, Taylor JR. Isozymes of NADP-linked Isocitric Dehydrogenase in Psoriasis and Human Basal Cell Carcinoma. Arch Dermatol. 1971;103(2):185-190. doi:10.1001/archderm.1971.04000140071012