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SpotLight Proteomics-A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications.

ABSTRACT: Sarcoidosis is a systemic interstitial lung disease of unknown aetiology. Less invasive diagnostics are needed to decipher disease pathology and to distinguish sub-phenotypes. Here we test if SpotLight proteomics, which combines de novo MS/MS sequencing of enriched IgG and co-extracted proteins with subsequent label-free quantification of new and known peptides, can differentiate controls and sarcoidosis phenotypes (Löfgrens and non-Löfgrens syndrome, LS and nonLS). Intra-individually matched IgG enriched from serum and bronchial lavage fluid (BALF) from controls (n = 12), LS (n = 11) and nonLS (n = 12) were investigated. High-resolution mass-spectrometry SpotLight proteomics and uni- and multivariate-statistical analyses were used for data processing. Major differences were particularly observed in control-BALF versus sarcoidosis-BALF. However, interestingly, information obtained from BALF profiles was still present (but less prominent) in matched serum profiles. By using information from orthogonal partial least squares discriminant analysis (OPLS-DA) differentiating 1) sarcoidosis-BALF and control-BALF and 2) LS-BALF vs. nonLS-BALF, control-serum and sarcoidosis-serum (p = 0.0007) as well as LS-serum and nonLS-serum (p = 0.006) could be distinguished. Noteworthy, many factors prominent in identifying controls and patients were those associated with Fc-regulation, but also features from the IgG-Fab region and novel peptide variants. Differences between phenotypes were mostly IgG-specificity related. The results support the analytical utility of SpotLight proteomics which prospectively have potential to differentiate closely related phenotypes from a simple blood test.

SUBMITTER: Lundstrom SL

PROVIDER: S-EPMC6540603 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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SpotLight Proteomics-A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications.

Lundström Susanna L SL Heyder Tina T Wiklundh Emil E Zhang Bo B Eklund Anders A Grunewald Johan J Zubarev Roman A RA

International journal of molecular sciences 20190501 9

Sarcoidosis is a systemic interstitial lung disease of unknown aetiology. Less invasive diagnostics are needed to decipher disease pathology and to distinguish sub-phenotypes. Here we test if SpotLight proteomics, which combines de novo MS/MS sequencing of enriched IgG and co-extracted proteins with subsequent label-free quantification of new and known peptides, can differentiate controls and sarcoidosis phenotypes (Löfgrens and non-Löfgrens syndrome, LS and nonLS). Intra-individually matched Ig ...[more]

PMID: 31052352

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Dataset Information

SpotLight Proteomics-A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications.

Publications

SpotLight Proteomics-A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications.

Similar Datasets

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