title: Multiplexed mass spectrometry monitoring of biomarker candidates for osteoarthritis.
abstract: The methods currently available for the diagnosis and monitoring of osteoarthritis (OA) are very limited and lack sensitivity. Being the most prevalent rheumatic disease, one of the most disabling pathologies worldwide and currently untreatable, there is a considerable interest pointed in the verification of specific biological markers for improving its diagnosis and disease progression studies. Considering the remarkable development of targeted proteomics methodologies in the frame of the Human Proteome Project, the aim of this work was to develop and apply a MRM-based method for the multiplexed analysis of a panel of 6 biomarker candidates for OA encoded by the Chromosome 16, and another 8 proteins identified in previous shotgun studies as related with this pathology, in specimens derived from the human joint and serum. The method, targeting 35 different peptides, was applied to samples from human articular chondrocytes, healthy and osteoarthritic cartilage, synovial fluid and serum. Subsequently, a verification analysis of the biomarker value of these proteins was performed by single point measurements on a set of 116 serum samples, leading to the identification of increased amounts of Haptoglobin and von Willebrand Factor in OA patients. Altogether, the present work provides a tool for the multiplexed monitoring of 14 biomarker candidates for OA, and verifies for the first time the increased amount of two of these circulating markers in patients diagnosed with this disease.
  
  
  
  We have developed an MRM method for the identification and relative quantification of a panel of 14 protein biomarker candidates for osteoarthritis. This method has been applied to analyze human articular chondrocytes, articular cartilage, synovial fluid, and finally a collection of 116 serum samples from healthy controls and patients suffering different degrees of osteoarthritis, in order to verify the biomarker usefulness of the candidates. HPT and VWF were validated as increased in OA patients.
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Patricia
authors.initials: P
authors.lastname: Fernández-Puente
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Valentina
authors.initials: V
authors.lastname: Calamia
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: González-Rodríguez
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Lourido
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Camacho-Encina
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Natividad
authors.initials: N
authors.lastname: Oreiro
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain; CIBER-BBN Instituto de Salud Carlos III, INIBIC-CHUAC, As Xubias 84, 15006 A Coruña, Spain. Electronic address: cristina.ruiz.romero@sergas.es.
authors.forename: Cristina
authors.initials: C
authors.lastname: Ruiz-Romero
authors.affiliation: Proteomics Group-PBR2-ProteoRed/ISCIII, Rheumatology Division, Instituto de Investigación Biomédica de A Coruña (INIBIC), Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas, Universidade da Coruña (UDC), As Xubias, 84, 15006 A Coruña, Spain; RIER-RED de Inflamación y Enfermedades Reumáticas, INIBIC-CHUAC, As Xubias 84, 15006 A Coruña, Spain. Electronic address: francisco.blanco.garcia@sergas.es.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Blanco
mesh_terms: D015415:Biomarkers / Q000032:analysis / Q000097:blood; D002358:Cartilage, Articular / Q000737:chemistry / Q000473:pathology; D016022:Case-Control Studies; D002460:Cell Line; D019902:Chondrocytes / Q000737:chemistry; D002885:Chromosomes, Human, Pair 16; D018450:Disease Progression; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D010003:Osteoarthritis / Q000175:diagnosis*; D010455:Peptides / Q000032:analysis; D013048:Specimen Handling; D013582:Synovial Fluid / Q000737:chemistry
chemical_list: D015415:Biomarkers; D010455:Peptides
keywords: Biomarkers; Cartilage; Chondrocytes; Osteoarthritis; SRM/MRM; Serum; Synovial fluid