Purification and characterization of CD38/ADP-ribosyl cyclase from rat lung

Purification and characterization of CD38/ADP-ribosyl cyclase in the rat lung tissue was performed with microsomes solubilized in Triton X-100 and the ADP-ribosyl cyclase was then purified using sequential column chromatography. Partially purified rat lung ADP-ribosyl cyclase was analyzed by immunoblotting using an antibody raised against a recombinant rat CD38 and showed the presence of monomer (42 kDa) and dimer (85 kDa) under non-reducing conditions but under reducing conditions, only the monomer was detected. Both the monomer and dimer could be eluted out in a stable manner from SDS-PAGE and the enzymatic activity was retained by the two different forms of CD38/ADP-ribosyl cyclase. Immunohistochemical staining showed the presence of CD38 on the bronchial epithelium and the alveoli.