title: Establishment of a highly sensitive sandwich ELISA for the N-terminal fragment of titin in urine.
abstract: Muscle damage and loss of muscle mass are triggered by immobilization, loss of appetite, dystrophies and chronic wasting diseases. In addition, physical exercise causes muscle damage. In damaged muscle, the N-terminal and C-terminal regions of titin, a giant sarcomere protein, are cleaved by calpain-3, and the resulting fragments are excreted into the urine via glomerular filtration. Therefore, we considered titin fragments as promising candidates for reliable and non-invasive biomarkers of muscle injury. Here, we established a sandwich ELISA that can measure the titin N-terminal fragment over a biologically relevant range of concentrations, including those in urine samples from older, non-ambulatory Duchenne muscular dystrophy patients and from healthy donors under everyday life conditions and after exercise. Our results indicate that the established ELISA could be a useful tool for the screening of muscular dystrophies and also for monitoring the progression of muscle disease, evaluating the efficacy of therapeutic approaches, and investigating exercise-related sarcomeric disruption and repair processes.
authors.affiliation: Diagnostic &Research Reagents Division, Immuno-biological Laboratories Co., Ltd. 1091-1 Naka, Fujioka-shi, Gunma 375-0005, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Maruyama
authors.affiliation: Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 1-1-3 Minatojima-Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Asai
authors.affiliation: Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation Foundation for Biomedical Research and Innovation, 2-2 Minatojima- Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Abe
authors.affiliation: Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation Foundation for Biomedical Research and Innovation, 2-2 Minatojima- Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Akari
authors.initials: A
authors.lastname: Inada
authors.affiliation: Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation Foundation for Biomedical Research and Innovation, 2-2 Minatojima- Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawauchi
authors.affiliation: Diagnostic &Research Reagents Division, Immuno-biological Laboratories Co., Ltd. 1091-1 Naka, Fujioka-shi, Gunma 375-0005, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Miyashita
authors.affiliation: Diagnostic &Research Reagents Division, Immuno-biological Laboratories Co., Ltd. 1091-1 Naka, Fujioka-shi, Gunma 375-0005, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Maeda
authors.affiliation: Department of Physical Therapy, Faculty of Rehabilitation, Kobe Gakuin University, 1-1-3 Minatojima-Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Matsuo
authors.affiliation: Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation Foundation for Biomedical Research and Innovation, 2-2 Minatojima- Minamimachi Chuo-ku, Kobe 650-0047, Japan.
authors.forename: Yo-Ichi
authors.initials: YI
authors.lastname: Nabeshima
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D002675:Child, Preschool; D064211:Connectin / Q000652:urine*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008875:Middle Aged; D009124:Muscle Proteins / Q000652:urine*; D018482:Muscle, Skeletal / Q000378:metabolism; D020388:Muscular Dystrophy, Duchenne / Q000378:metabolism / Q000652:urine; D010805:Physical Conditioning, Animal / Q000502:physiology; D012518:Sarcomeres / Q000378:metabolism; D055815:Young Adult
chemical_list: D064211:Connectin; D009124:Muscle Proteins; C577285:TTN protein, human