Alpha‐Klotho, a critical protein for lung health, is not expressed in normal lung

Alpha‐Klotho (αKlotho), produced by the kidney and selected organs, is essential for tissue maintenance and protection. Homozygous αKlotho‐deficiency leads to premature multi‐organ degeneration and death; heterozygous insufficiency leads to apoptosis, oxidative stress, and increased injury susceptib...

Full description

Saved in:
Bibliographic Details
Published in:FASEB bioAdvances 2019-11, Vol.1 (11), p.675-687
Main Authors: Zhang, Jianning, Cao, Khoa, Pastor, Johanne V., Li, Liping, Moe, Orson W., Hsia, Connie C. W.
Format: Article
Language:English
Subjects:
human
immunoblot
immunohistochemistry
inhalational cDNA delivery
mice
monoclonal antibodies
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Alpha‐Klotho (αKlotho), produced by the kidney and selected organs, is essential for tissue maintenance and protection. Homozygous αKlotho‐deficiency leads to premature multi‐organ degeneration and death; heterozygous insufficiency leads to apoptosis, oxidative stress, and increased injury susceptibility. There is inconsistent data in the literature regarding whether αKlotho is produced locally in the lung or derived from circulation. We probed murine and human lung by immunohistochemistry (IHC) and immunoblot (IB) using two monoclonal (anti‐αKlotho Kl1 and Kl2 domains) and three other common commercial antibodies. Monoclonal anti‐Kl1 and anti‐Kl2 yielded no labeling in lung on IHC or IB; specific labeling was observed in kidney (positive control) and also murine lungs following tracheal delivery of αKlotho cDNA, demonstrating specificity and ability to detect artificial pulmonary expression. Other commercial antibodies labeled numerous lung structures (IHC) and multiple bands (IB) incompatible with known αKlotho mobility; labeling was not abolished by blocking with purified αKlotho or using lungs from hypomorphic αKlotho‐deficient mice, indicating nonspecificity. Results highlight the need for rigorous validation of reagents. The lung lacks native αKlotho expression and derives full‐length αKlotho from circulation; findings could explain susceptibility to lung injury in extrapulmonary pathology associated with reduced circulating αKlotho levels, for example, renal failure. Conversely, αKlotho may be artificially expressed in the lung, suggesting therapeutic opportunities.
ISSN:2573-9832
2573-9832
DOI:10.1096/fba.2019-00016