Giacomo Rößler, Jonas Labode, Julia Schipke, Stefan A Tschanz, Christian Mühlfeld
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引用次数: 0
Abstract
Background: A comprehensive understanding of vascular development in the human lung is still missing.
Methods: Therefore, samples of infant (n = 5, 26 days to 18 months postnatally) and adult (n = 5, 20 to 40 years) human lungs were subjected to unbiased stereological estimation of the total number of capillary loops. Serial sections were segmented to visualize the alveolar capillary network (ACN) in 3D.
Results: The number of capillary loops increased in parallel to lung volume from 26 days to 18 months, while in adults, it was not correlated to lung volume. In infant lungs, two capillary layers were separated by a connective tissue sheet with a growing number of interconnections. In adults, the mature ACN was almost, but not completely, single-layered. Here, the connective tissue was thinner but still centrally positioned, suggesting the persistence of interconnected parts of both layers of the previously double-layered ACN.
Conclusions: Small parts of the capillaries remain double-layered and seem to be grouped around the thin connective tissue sheet, suggesting a different mechanism of microvascular maturation than simple fusion of the two layers. These spots are a potential basis for further alveolarization after completion of bulk formation.
Impact: The 3D data offer a new conceptual approach to microvascular maturation of the lung. Microvascular maturation rather results from reduction than simple fusion of capillary fragments. Adult lungs maintain small double-layered capillary spots. These could offer a potential source of regeneration. The data are important to better understand normal and pathological lung development.
期刊介绍:
Pediatric Research publishes original papers, invited reviews, and commentaries on the etiologies of children''s diseases and
disorders of development, extending from molecular biology to epidemiology. Use of model organisms and in vitro techniques
relevant to developmental biology and medicine are acceptable, as are translational human studies