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Review
. 2021 Nov 25;33(12):665-671.
doi: 10.1093/intimm/dxab040.

Macrophages in lung fibrosis

Tatsuro Ogawa  1 , Shigeyuki Shichino  1 , Satoshi Ueha  1 , Kouji Matsushima  1
Affiliations
Review

Macrophages in lung fibrosis

Tatsuro Ogawa et al. Int Immunol. .

Abstract

Pulmonary fibrosis (PF) is a disease in which excessive extracellular matrix (ECM) accumulation occurs in the lungs, which induces thickening of the alveolar walls, ultimately leading to the destruction of alveolar structures and respiratory failure. Idiopathic PF, the cause of which is unknown, has a poor prognosis with a median survival of 2-4 years after diagnosis. There is currently no known curative treatment. The mechanism underlying PF is thought to be initiated by the dysfunction of type II alveolar epithelial cells, which leads to ECM overproduction through the activation of fibroblasts. In addition, it has been suggested that a variety of cells contribute to fibrotic processes. In particular, clinical and basic research findings examining the roles of macrophages suggest that they may be pivotal regulators of PF. In this review, we discuss the characteristics, functions and origins of subsets of macrophages involved in PF, including resident alveolar, interstitial and monocyte-derived macrophages.

Keywords: chemokine; fibroblasts; growth factor; interstitial lung disease; single-cell transcriptome.

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Figures

Fig. 1.
Fig. 1.
Composition and localization of macrophages in normal and fibrotic lungs in mice. There are two distinct groups of tissue macrophages in the normal lung: alveolar and interstitial. Both are capable of self-renewal but are slowly replaced by monocyte-derived macrophages. Furthermore, it has been reported that there are two subsets of interstitial macrophages: Lyve1hi MHCIIlo interstitial macrophages are localized in the perivascular area, whereas Lyve1lo MHC IIhi interstitial macrophages are found in the alveolar interstitium. In the fibrotic lungs, classical monocytes infiltrate in a CCR2-dependent manner and differentiate based on the specific tissue environment. However, it is worth noting that there are conflicting reports on the roles of these cells in fibrosis. Lyve1lo MHC IIhi interstitial macrophages have also been shown to increase during fibrosis.
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References

    1. Olson, A., Hartmann, N., Patnaik, P.et al. . 2021. Estimation of the prevalence of progressive fibrosing interstitial lung diseases: systematic literature review and data from a physician survey. Adv. Ther. 38:854. - PMC - PubMed
    1. Lederer, D. J. and Martinez, F. J. 2018. Idiopathic pulmonary fibrosis. N. Engl. J. Med. 378:1811. - PubMed
    1. Richeldi, L., Collard, H. R. and Jones, M. G. 2017. Idiopathic pulmonary fibrosis. Lancet 389:1941. - PubMed
    1. The Idiopathic Pulmonary Fibrosis Clinical Research Network. 2012. Prednisone, azathioprine, and N-acetylcysteine for pulmonary fibrosis. N. Engl. J. Med. 366:1968. - PMC - PubMed
    1. Parimon, T., Yao, C., Stripp, B. R.et al. . 2020. Alveolar epithelial type II cells as drivers of lung fibrosis in idiopathic pulmonary fibrosis. Int. J. Mol. Sci. 21:2269. - PMC - PubMed

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