Extract
Pulmonary interstitial glycogenosis (PIG) was first defined as a distinct neonatal interstitial lung disease of unknown aetiology that presents in neonates and young infants with mild to severe hypoxic lung disease [1]. Characterised clinically by unexplained respiratory distress and cyanosis with an onset during early infancy, PIG was primarily defined by the presence of distinct and unusual-appearing cells contained within the interstitium that were characterised by a widened interstitium containing variable numbers of immature-appearing, polygonal-to-spindle shaped cells, which may contribute to impaired gas exchange. The most unique feature of PIG cells is the widespread presence of non-membrane bound, periodic acid-Schiff stain-positive, mono-particulate glycogen in the cytoplasm, for which the disease was named (“glycogenosis”) [1]. By ultrastructure, PIG cells are considered primitive due to the presence of only sparse organelles and a lack of specific features that indicate differentiation towards any well-characterised pulmonary cell line, including lymphocytes or macrophages [1].
Abstract
Pulmonary interstitial glycogenesis (PIG) is characterised by a unique but poorly characterised cell population in developmental lung disease. This study reports that PIG cells express cellular markers, suggesting a mesenchymal stem cell lineage. https://bit.ly/2YNdDIY
Footnotes
Author contributions: C. Galambos developed the project, collected cases, interpreted histologic data and wrote the manuscript; E. Wartchow collected and interpreted ultrastructural data, and reviewed and edited the manuscript; J.P. Weinman collected and interpreted imaging data, and reviewed the manuscript; S.H. Abman interpreted clinical data, and reviewed and edited the manuscript.
Conflict of interest: C. Galambos has nothing to disclose.
Conflict of interest: E. Wartchow has nothing to disclose.
Conflict of interest: J.P. Weinman has nothing to disclose.
Conflict of interest: S.H. Abman has nothing to disclose.
Support statement: The authors are grateful for grant support provided by the National Organization for Rare Disorders, The Linda Crnic Institute Grant (C. Galambos), and Jayden DeLuca Foundation (C. Galambos), and the NIH HL68702 (S.H. Abman) and HL145679 (S.H. Abman). Funding information for this article has been deposited with the Crossref Funder Registry.
- Received March 27, 2020.
- Accepted May 4, 2020.
- Copyright ©ERS 2020