Dataset Information

Hemoglobin ? and ? are ubiquitous in the human lung, decline in idiopathic pulmonary fibrosis but not in COPD.

ABSTRACT:

Background

Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) are disorders of the lung parenchyma. They share the common denominators of a progressive nature and poor prognosis. The goal was to use non-biased proteomics to discover new markers for these diseases.

Methods

Proteomics of fibrotic vs. control lung tissue suggested decreased levels of several spots in the lung specimens of IPF patients, which were identified as Hemoglobin (Hb) ? and ? monomers and Hb? complexes. The Hb? and ? monomers and complexes were investigated in more detail in normal lung and lung specimens of patients with IPF and COPD by immunohistochemistry, morphometry and mass spectrometry (MS).

Results

Both Hb monomers, in normal lung, were expressed especially in the alveolar epithelium. Levels of Hb? and ? monomers and complexes were reduced/lost in IPF but not in the COPD lungs when compared to control lung. MS-analyses revealed Hb? modification at cysteine105 (Cys?105), preventing formation of the Hb? complexes in the IPF lungs. Hb? and Hb? were expressed as complexes and monomers in the lung tissues, but were secreted into the bronchoalveolar lavage fluid and/or induced sputum supernatants as complexes corresponding to the molecular weight of the Hb tetramer.

Conclusions

The abundant expression of the oxygen carrier molecule Hb in the normal lung epithelium and its decline in IPF lung are new findings. The loss of Hb complex formation in IPF warrants further studies and may be considered as a disease-specific modification.

SUBMITTER: Ishikawa N

PROVIDER: S-EPMC2949726 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Publications

Hemoglobin α and β are ubiquitous in the human lung, decline in idiopathic pulmonary fibrosis but not in COPD.

Ishikawa Nobuhisa N Ohlmeier Steffen S Salmenkivi Kaisa K Myllärniemi Marjukka M Rahman Irfan I Mazur Witold W Kinnula Vuokko L VL

Respiratory research 20100913

<h4>Background</h4>Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) are disorders of the lung parenchyma. They share the common denominators of a progressive nature and poor prognosis. The goal was to use non-biased proteomics to discover new markers for these diseases.<h4>Methods</h4>Proteomics of fibrotic vs. control lung tissue suggested decreased levels of several spots in the lung specimens of IPF patients, which were identified as Hemoglobin (Hb) α and β ...[more]

PMID: 20836851

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