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C Kinnon

Publications and source records attributed to C Kinnon.

97 records · Page 6Linked to original sources
PubMed1980

Effect of tunicamycin and cycloheximide on the secretion of acid hydrolases from I-cell cultured fibroblasts.

I-cell cultures fibroblasts secrete excessive amounts of N-acetyl-beta-D-hexosaminidase and alpha-L-fucosidase into the culture media as compared with normal fibroblasts. Addition of tunicamycin or cyd [14C]leucine (40--50%) into trichloroacetic acid-precipitable material decreased the secretion of these I-cell hydrolases to normal values within 24 h, but had no effect on the secretion of acid hydrolases from normal fibroblasts. These results indicate that I-cell cultured fibroblasts secrete at least two types of acid hydrolases: one is tunicamycin- and cycloheximide-sensitive and constitutes the greater proportion of the secreted hydrolases, and a smaller proportion is insensitive to tunicamycin and cycloheximide, similar t9 the acid hydrolases secreted by normal cultured fibroblasts.

Cells, Cultured↗
PubMedDate not supplied

Non-viral, integrin-mediated gene transfer into fibroblasts from patients with lysosomal storage diseases.

BACKGROUND: Non-viral vectors consisting of Lipofectin/integrin-targeting peptide/DNA (LID) complexes have great potential for gene therapy, as they are safe, simple, and able to package large DNA molecules. In this study, these vectors were evaluated in vitro for the therapy of lysosomal storage disorders. METHODS: Non-viral vectors were designed to deliver therapeutic genes by integrin-mediated uptake into fibroblasts from patients with the lysosomal storage disorders fucosidosis and Fabry disease, which result from deficiencies of alpha-L-fucosidase and alpha-galactosidase A, respectively. The vectors consisted of a complex (LID) of Lipofectin and a peptide containing an integrin-targeting domain and a poly-lysine domain to which was bound plasmid DNA, containing alpha-L-fucosidase (LID-alpha-Fuc) or alpha-galactosidase A (LID-alpha-Gal). RESULTS: Patients' fibroblasts transfected with LID-alpha-Fuc and LID-alpha-Gal produced the corresponding enzyme at levels which were 10-40% of the total activity in cultures of normal fibroblasts. However, 95-98% of this activity was secreted. Transfection of endothelial cells, the main target cells in Fabry disease, with an LID-alpha-Gal produced a total alpha-galactosidase activity 65% higher than that in untransfected cultures after 6 days, 67% of the activity being secreted. Although transfection of fibroblasts with LID complexes also caused small changes in the distribution of endogenous lysosomal enzymes, it did not appear to affect the viability of the cells. CONCLUSIONS: The integrin-mediated transfer of genes encoding lysosomal enzymes into cells results in the secretion of large amounts of normal enzyme that could be taken up by other cells. This could be a useful strategy for enzyme-replacement therapy.

Cell Line↗
PubMedDate not supplied

Wiskott-Aldrich syndrome protein, WASP.

Wiskott-Aldrich Syndrome protein (WASP) is the product of the gene mutated in children with Wiskott-Aldrich Syndrome (WAS). It is a predominantly cytoplasmic protein, expressed only in haematopoietic cells. It binds in vivo to the adaptor proteins Nck and Grb2, to the cytoplasmic protein-tyrosine kinase Fyn and to the small Rho-like GTPase Cdc42, which is required for formation of filopodia in fibroblasts and macrophages. WASP also interacts, directly or indirectly, with the actin cytoskeleton. Together with studies of a closely related, ubiquitously expressed protein named N-WASP, these findings suggest that WASP is a component of signalling pathways that control reorganisation of the actin cytoskeleton in haematopoietic cells in response to external stimuli. In support of this idea, haematopoietic cells from WAS patients show defects in cytoskeletal organisation that compromise their ability to polarise and to migrate in response to physiological stimuli. These defects could account for many of the clinical features of WAS. WAS is now a candidate for gene therapy based on the delivery of a wild-type WASP gene to autologous haematopoietic stem cells. In addition, recent studies of cell defects in WAS patients suggest that it may prove possible, in time, to rescue WAS cells using more conventional drug therapies.

Humans↗
PubMedDate not supplied

Genes in diagnosis and therapy.

With the recent exponential increase in our knowledge of human genes it is opportune to assess the impact this information will make on current clinical practice. In this review particular attention is paid to the advances being made in diagnostic techniques and to the possibilities for improved forms of treatment, particularly the use of recombinant gene products and somatic gene therapy.

Genetic Diseases, Inborn↗