Murine cellular model of mucopolysaccharidosis, type IIIB (MPS IIIB) - A preliminary study with particular emphasis on the non-oxidative l-cysteine metabolism.

The lack of the N-alpha-glucosaminidase (Naglu) is responsible for the incidence of a rare disease - mucopolysaccharidosis, type IIIB (MPS IIIB). To date, studies have been conducted based on cells derived from patients suffering from MPS or using in vivo MPS mouse models. These limitations have allowed for defining our research goal - to create and characterize the first in vitro murine cellular MPS IIIB model. In the current work we present a new, stable cell line with confirmed accumulation of glycosaminoglycans. The line stability was achieved by immortalization using a lentivirus carrying the T-antigens of SV40. The Naglu^-/- cells were confirmed to produce no Naglu enzyme. To confirm the proper functioning of the in vitro MPS IIIB model, we determined the activity and expression of cystathionine γ-lyase, rhodanese and 3-mercaptopyruvate sulfurtransferase, as well as the level of low molecular-weight thiols (reduced and oxidized glutathione, cysteine and cystine). The results were referred to our earlier findings originating from the studies on the tissues of the Naglu^-/- mice that were used to create the lines. The results obtained in the Naglu^-/- cells were in accordance with the results found in the mouse model of MPS IIIB. It suggests that the presented murine Naglu^-/- cell lines might be a convenient in vitro model of MPS IIIB.