PNP (Purine Nucleoside Phosphorylase)

Abstract

The purine nucleoside phosphorylase gene (PNP) encodes an enzyme which reversibly catalyzes the phosphorolysis of purine nucleosides. PNP is ubiquitously expressed in mammalian cells and tissues. PNP mutations cause nucleoside phosphorylase deficiency which result in defective T cell mediated immunity but can also affect B cell immunity and antibody responses.