University of Iowa Research Foundation

Other

Washington University

Volker Straub

Kevin P Campbell

Franck Duclos

Daniel Yonil Jung

John McPherson

Beverly L Davidson

Roger Williamson

Yoshihide Sunada

Leland E Lim

Valerie Allamand

Mustafa Salih

Kathleen H Holt

Disclosed is a method for treating a patient suffering from the disease sarcoglycan-deficient limb-girdle muscular dystrophy by gene replacement therapy. Sarcoglycan gene replacement therapy produces extensive long-term expression of the sarcoglycan species which restores the entire sarcoglycan complex, results in the stable association of alph&agr;-dystroglycan with the sarcolemma, and eliminates the morphological markers of limb-girdle muscular dystrophy. In another aspect, the invention relates to a method for determining a specific defective sarcoglycan species in the tissue of a patient. The method involves culture of muscle cells obtained from the patient, and the independent introduction of expression vectors encoding each of the sarcoglycan species, &agr;, &bgr;, &ggr;, and &dgr;, into the cultured cells with subsequent assaying for restoration of the dystrophin-glycoprotein complex. In another aspect, the invention relates to a mouse, and cells derived therefrom, homozygous for a disrupted &agr;-sarcoglycan gene. The disruption prevents the synthesis of functional &agr;-sarcoglycan in cells of the mouse and results in the mutant mouse having no detectable sarcospan, &bgr;-, &ggr;-, &dgr;-sarcoglycan, and reduced &agr;-dystroglycan in the sarcolemma of skeletal and cardiac muscles, and a reduction of dystrophin in skeletal muscle, when compared to tissue of a mouse lacking a disrupted &agr;-sarcoglycan gene. In another aspect, the invention relates to methods for screening for therapeutic agents useful in the treatment of sarcoglycan-deficient limb-girdle muscular dystrophy. The methods involve administering a candidate therapeutic agent to a mouse, or cells derived therefrom, and assaying for therapeutic effects on the mouse or cells, with the determination of therapeutic effects being a reduction or reversal in disease progression, or a restoration of the dystroglycan complex.

Gene replacement therapy for muscular dystrophy

Disclosed herein is a substantially pure nucleic acid sequence encoding a mammalian 35 kDa non-dystrophin component (&dgr;-sarcoglycan) of the dystrophin-glycoprotein complex. Also disclosed are the amino acid sequence and an immunogenic peptide of &dgr;-sarcoglycan. The peptide when used to immunize a mammal, stimulates the production of antibodies which bind specifically to the &dgr;-sarcoglycan. Methods to identify mutations in the &dgr;-sarcoglycan gene associated with autosomal recessive limb-girdle muscular dystrophy are also disclosed. The identification of such mutations enables the design of nucleic acid probes which hybridize specifically to a mutant form of &dgr;-sarcoglycan, or the complement thereof, but not to the DNA of the wild-type form of the gene (or the complement thereof), under stringent hybridization conditions. Such probes are useful, for example, in connection with the diagnosis of autosomal recessive limb-girdle muscular dystrophy. In addition, the identification of such mutations enables the diagnosis of autosomal recessive limb-girdle muscular dystrophy through the use of direct DNA sequencing techniques.

&dgr;-sarcoglycan antibodies

Disclosed are compositions and methods for aiding in the diagnosis of congenital muscular dystrophy associated with in-frame deletion in the laminin-2 .alpha.2 polypeptide chain in an individual. In a preferred diagnostic method embodiment, an experimental muscle tissue sample is provided from the individual and treated if necessary to render components available for antibody binding. The components of the sample are then separated on the basis of molecular weight. The separated protein components are then transferred to a solid support while maintaining the relative positions established in separation step. The transferred components are then stained with an affinity reagent which is known to bind to a C-terminal domain of the laminin-2 .alpha.2 polypeptide chain. Individual afflicted with congenital muscular dystrophy associated with in-frame deletion in the laminin-2 .alpha.2 polypeptide chain on the basis of positive staining in combination with reduced molecular weight of the laminin-2 .alpha.2 polypeptide chain relative to the wild-type laminin-2 .alpha.2 polypeptide chain. A preferred composition is a nucleic acid probe for the detection of merosin deletion-type congenital muscular dystrophy. The preferred nucleic acid probe is characterized by the ability to bind specifically to a mutant merosin nucleic acid sequence, the mutant merosin nucleic acid sequence comprising a T to C substitution at position 3973 +2 of the consensus donor splice site of exon 25.

Method for aiding in the diagnosis of in-frame deletion type congenital

Disclosed herein is a substantially pure nucleic acid sequence encoding a mammalian 35 kDa non-dystrophin component (.delta.-sarcoglycan) of the dystrophin-glycoprotein complex. Also disclosed are the amino acid sequence and an immunogenic peptide of .delta.-sarcoglycan. The peptide when used to immunize a mammal, stimulates the production of antibodies which bind specifically to the .delta.-sarcoglycan. Methods to identify mutations in the .delta.-sarcoglycan gene associated with autosomal recessive limb-girdle muscular dystrophy are also disclosed. The identification of such mutations enables the design of nucleic acid probes which hybridize specifically to a mutant form of .delta.-sarcoglycan, or the complement thereof, but not to the DNA of the wild-type form of the gene (or the complement thereof), under stringent hybridization conditions. Such probes are useful, for example, in connection with the diagnosis of autosomal recessive limb-girdle muscular dystrophy. In addition, the identification of such mutations enables the diagnosis of autosomal recessive limb-girdle muscular dystrophy through the use of direct DNA sequencing techniques.

.delta.-sarcoglycan nucleic acid sequences

Growing community of inventors

Essen, IA, United States of America

Volker Straub