Detection of neuron-specific protein gene product (PGP) 9.5 in the rat and zebrafish using anti-human PGP9.5 antibodies.

Protein gene product (PGP) 9.5 is a developmentally regulated neuron- and neuroendocrine cell-specific ubiquitin carboxy-terminal hydrolase (UCHL1) expressed throughout the mammalian central and peripheral nervous systems. We have compared the use of monoclonal and polyclonal antibodies raised against human PGP9.5 for immunodetection of the protein in tissues of the zebrafish and rat. We show that a monoclonal antibody 13C4, which recognises an N-terminal epitope, detects PGP9.5 on Western blots as a single 27 kDa band present at high levels in zebrafish and rat brain. By contrast, the polyclonal antisera recognises multiple tissue-specific proteins in the rat and fails to detect PGP9.5 in the zebrafish. Finally, we have developed a specific ELISA assay for detection of cellular PGP9.5 using MAb13C4 and have employed the assay to show that PGP9.5 is not upregulated during nerve growth factor (NGF)-induced differentiation of rat PC12 cells.