학술논문

Activation of the pentose phosphate pathway in macrophages is crucial for granuloma formation in sarcoidosis
Document Type
Report
Source
Journal of Clinical Investigation. December 2023, Vol. 133 Issue 23
Subject
Japan
Language
English
ISSN
0021-9738
Abstract
Sarcoidosis is a disease of unknown etiology in which granulomas form throughout the body and is typically treated with glucocorticoids, but there are no approved steroid-sparing alternatives. Here, we investigated the mechanism of granuloma formation using single-cell RNA-Seq in sarcoidosis patients. We observed that the percentages of triggering receptor expressed on myeloid cells 2-positive (TREM2- positive) macrophages expressing angiotensin- converting enzyme (ACE) and lysozyme, diagnostic makers of sarcoidosis, were increased in cutaneous sarcoidosis granulomas. Macrophages in the sarcoidosis lesion were hypermetabolic, especially in the pentose phosphate pathway (PPP). Expression of the PPP enzymes, such as fructose-1,6-bisphosphatase 1 (FBP1), was elevated in both systemic granuloma lesions and serum of sarcoidosis patients. Granuloma formation was attenuated by the PPP inhibitors in in vitro giant cell and in vivo murine granuloma models. These results suggest that the PPP may be a promising target for developing therapeutics for sarcoidosis.
Introduction Granulomas are chronic inflammatory lesions having well-defined borders and comprising mainly macrophages and other inflammatory cells (1). Differentiation of macrophages into epithelioid cells and multinucleated giant cells is often [...]