Development, characterisation and epitope mapping of novel monoclonal antibodies for DJ-1 (PARK7) protein

Mutations in DJ-1 (PARK7) were recently identified as the cause for an autosomal recessive early onset form of familial Parkinson's disease, however, the function of the protein in the brain is yet to be elucidated. Here we report on the development, characterisation and epitope mapping, of two novel monoclonal antibodies to DJ-1. One of them (DJ-1 "clone16") has its epitope between amino acids 56-78 of the human DJ-1 protein and has very similar properties to a commercially available DJ-1 antibody clone 3E8. The second antibody recognised both the rat and human DJ-1 (DJ-1 "clone 48") and its epitope is between amino acids 26-56. We have used immunohistochemistry with these two antibodies to compare the distribution of DJ-1 in human and rat brain tissue. Both antibodies gave similar patterns of labelling in human brain with marked astrocytic expression. Neuronal labelling was weak or absent and the antibodies did not label Lewy bodies or Lewy neurites. In the rat brain, DJ-1 was ubiquitously expressed in neurones but exhibited low expression in astrocytes. These antibodies could be exploited as important tools in dissecting out DJ-1 expression in different species and examination of the role of DJ-1 in Parkinson's disease.