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Najrana T, Ahsan N, Abu-Eid R, Uzun A, Noble L, Tollefson G, Sanchez-Esteban J. Proteomic analysis of a murine model of lung hypoplasia induced by oligohydramnios. Pediatr Pulmonol 2021; 56:2740-2750. [PMID: 34102042 PMCID: PMC8631439 DOI: 10.1002/ppul.25525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 05/09/2021] [Accepted: 05/23/2021] [Indexed: 02/02/2023]
Abstract
Severe oligohydramnios (OH) due to prolonged loss of amniotic fluid can cause pulmonary hypoplasia. Animal model of pulmonary hypoplasia induced by amniotic fluid drainage is partly attributed to changes in mechanical compression of the lung. Although numerous studies on OH-model have demonstrated changes in several individual proteins, however, the underlying mechanisms for interrupting normal lung development in response to a decrease of amniotic fluid volume are not fully understood. In this study, we used a proteomic approach to explore differences in the expression of a wide range of proteins after induction of OH in a mouse model of pulmonary hypoplasia to find out the signaling/molecular pathways involved in fetal lung development. Liquid chromatography-massspectromery/mass spectrometry analysis found 474 proteins that were differentially expressed in OH-induced hypoplastic lungs in comparison to untouched (UnT) control. Among these proteins, we confirmed the downregulation of AKT1, SP-D, and CD200, and provided proof-of-concept for the first time about the potential role that these proteins could play in fetal lung development.
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Affiliation(s)
- Tanbir Najrana
- Department of Pediatrics, Women and Infants Hospital/Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA.,Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island, USA
| | - Nagib Ahsan
- COBRE Center for Cancer Research Development at Rhode Island Hospital, Proteomics Core Facility, Division of Surgical Research, Brown University, Providence, Rhode Island, USA.,Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA.,Mass Spectrometry, Proteomics and Metabolomic Core Facility, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA
| | - Rasha Abu-Eid
- Institute of Dentistry, School of Medicine, Medical Sciences & Nutrition, University of Aberdeen, Foresterhill, UK
| | - Alper Uzun
- Department of Pediatrics, Women and Infants Hospital/Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA.,Center of Computational Molecular Biology, Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island, USA
| | - Lelia Noble
- COBRE Center for Cancer Research Development at Rhode Island Hospital, Proteomics Core Facility, Division of Surgical Research, Brown University, Providence, Rhode Island, USA
| | - George Tollefson
- Department of Pediatrics, Women and Infants Hospital/Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Juan Sanchez-Esteban
- Department of Pediatrics, Women and Infants Hospital/Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
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Pulmonary Hypoplasia Induced by Oligohydramnios: Findings from Animal Models and a Population-Based Study. Pediatr Neonatol 2017; 58:3-7. [PMID: 27324123 DOI: 10.1016/j.pedneo.2016.04.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 11/26/2015] [Accepted: 04/21/2016] [Indexed: 10/21/2022] Open
Abstract
Pulmonary hypoplasia is a substantial cause of death in newborn infants, and oligohydramnios is one of the most commonly associated abnormalities. Lung growth is influenced by physical factors such as the intrauterine space, lung liquid volume and pressure, and fetal breathing movements. During lung development, the main physical force experienced by the lungs is stretching induced by breathing movements and the lung fluid in the airspaces. Oligohydramnios reduces the intrathoracic cavity size, thus disrupting fetal lung growth and leading to pulmonary hypoplasia. The exact mechanism by which oligohydramnios alters the respiratory system structure and the effect of oligohydramnios on long-term respiratory outcomes remain unknown. In this review, we summarize the effects of oligohydramnios on lung development, discuss the mechanisms of oligohydramnios-induced pulmonary hypoplasia identified in various animal studies, and describe the long-term respiratory outcomes in childhood of oligohydramnios-exposed fetuses reported by a population-based study.
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Donahoe PK, Longoni M, High FA. Polygenic Causes of Congenital Diaphragmatic Hernia Produce Common Lung Pathologies. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2532-43. [PMID: 27565037 DOI: 10.1016/j.ajpath.2016.07.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/20/2016] [Accepted: 07/13/2016] [Indexed: 12/12/2022]
Abstract
Congenital diaphragmatic hernia (CDH) is one of the most common and lethal congenital anomalies, and significant evidence is available in support of a genetic contribution to its etiology, including single-gene knockout mice associated with diaphragmatic defects, rare monogenetic disorders in humans, familial aggregation, and association of CDH with chromosomal abnormalities. Structural lung defects in the form of lung hypoplasia are almost invariably seen in patients with CDH and frequently in animal models of this condition. Better understanding of the mechanisms of pulmonary defects in CDH has the potential for creating targeted therapies, particularly in postnatal stages, when therapeutics can have maximum clinical impact on the surviving cohorts. Successful treatment of CDH is dependent on the integration of human genomic and genetic data with developmental expression profiling, mouse knockouts, and gene network and pathway modeling, which have generated a large number of candidate genes and pathways for follow-up studies. In particular, defective alveolarization appears to be a common and potentially actionable phenotype in both patients and animal models.
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Affiliation(s)
- Patricia K Donahoe
- Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, Massachusetts; Department of Surgery, Harvard Medical School, Boston, Massachusetts; Broad Institute of the Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts.
| | - Mauro Longoni
- Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, Massachusetts; Department of Surgery, Harvard Medical School, Boston, Massachusetts
| | - Frances A High
- Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, Massachusetts; Department of Surgery, Harvard Medical School, Boston, Massachusetts; Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts; Department of Surgery, Boston Children's Hospital, Boston, Massachusetts
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Loscertales M, Nicolaou F, Jeanne M, Longoni M, Gould DB, Sun Y, Maalouf FI, Nagy N, Donahoe PK. Type IV collagen drives alveolar epithelial-endothelial association and the morphogenetic movements of septation. BMC Biol 2016; 14:59. [PMID: 27412481 PMCID: PMC4942891 DOI: 10.1186/s12915-016-0281-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/01/2016] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Type IV collagen is the main component of the basement membrane that gives strength to the blood-gas barrier (BGB). In mammals, the formation of a mature BGB occurs primarily after birth during alveologenesis and requires the formation of septa from the walls of the saccule. In contrast, in avians, the formation of the BGB occurs rapidly and prior to hatching. Mutation in basement membrane components results in an abnormal alveolar phenotype; however, the specific role of type IV collagen in regulating alveologenesis remains unknown. RESULTS We have performed a microarray expression analysis in late chick lung development and found that COL4A1 and COL4A2 were among the most significantly upregulated genes during the formation of the avian BGB. Using mouse models, we discovered that mutations in murine Col4a1 and Col4a2 genes affected the balance between lung epithelial progenitors and differentiated cells. Mutations in Col4a1 derived from the vascular component were sufficient to cause defects in vascular development and the BGB. We also show that Col4a1 and Col4a2 mutants displayed disrupted myofibroblast proliferation, differentiation and migration. Lastly, we revealed that addition of type IV collagen protein induced myofibroblast proliferation and migration in monolayer culture and increased the formation of mesenchymal-epithelial septal-like structures in co-culture. CONCLUSIONS Our study showed that type IV collagen and, therefore the basement membrane, play fundamental roles in coordinating alveolar morphogenesis. In addition to its role in the formation of epithelium and vasculature, type IV collagen appears to be key for alveolar myofibroblast development by inducing their proliferation, differentiation and migration throughout the developing septum.
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Affiliation(s)
- Maria Loscertales
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA.
- Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA.
| | - Fotini Nicolaou
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Marion Jeanne
- Departments of Ophthalmology and Anatomy, Institute for Human Genetics, University of California, San Francisco, School of Medicine, San Francisco, CA, 94143, USA
| | - Mauro Longoni
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Douglas B Gould
- Departments of Ophthalmology and Anatomy, Institute for Human Genetics, University of California, San Francisco, School of Medicine, San Francisco, CA, 94143, USA
| | - Yunwei Sun
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Faouzi I Maalouf
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Nandor Nagy
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
- Department of Human Anatomy, Histology and Embryology, Faculty of Medicine, Semmelweis University, Budapest, 1094, Hungary
| | - Patricia K Donahoe
- The Pediatric Surgical Research Laboratories, Massachusetts General Hospital, Boston, MA, 02114, USA
- Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
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Mižíková I, Morty RE. The Extracellular Matrix in Bronchopulmonary Dysplasia: Target and Source. Front Med (Lausanne) 2015; 2:91. [PMID: 26779482 PMCID: PMC4688343 DOI: 10.3389/fmed.2015.00091] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/08/2015] [Indexed: 12/22/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD) is a common complication of preterm birth that contributes significantly to morbidity and mortality in neonatal intensive care units. BPD results from life-saving interventions, such as mechanical ventilation and oxygen supplementation used to manage preterm infants with acute respiratory failure, which may be complicated by pulmonary infection. The pathogenic pathways driving BPD are not well-delineated but include disturbances to the coordinated action of gene expression, cell-cell communication, physical forces, and cell interactions with the extracellular matrix (ECM), which together guide normal lung development. Efforts to further delineate these pathways have been assisted by the use of animal models of BPD, which rely on infection, injurious mechanical ventilation, or oxygen supplementation, where histopathological features of BPD can be mimicked. Notable among these are perturbations to ECM structures, namely, the organization of the elastin and collagen networks in the developing lung. Dysregulated collagen deposition and disturbed elastin fiber organization are pathological hallmarks of clinical and experimental BPD. Strides have been made in understanding the disturbances to ECM production in the developing lung, but much still remains to be discovered about how ECM maturation and turnover are dysregulated in aberrantly developing lungs. This review aims to inform the reader about the state-of-the-art concerning the ECM in BPD, to highlight the gaps in our knowledge and current controversies, and to suggest directions for future work in this exciting and complex area of lung development (patho)biology.
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Affiliation(s)
- Ivana Mižíková
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; Pulmonology, Department of Internal Medicine, University of Giessen and Marburg Lung Center, Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; Pulmonology, Department of Internal Medicine, University of Giessen and Marburg Lung Center, Giessen, Germany
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Ahlfeld SK, Conway SJ. Aberrant signaling pathways of the lung mesenchyme and their contributions to the pathogenesis of bronchopulmonary dysplasia. ACTA ACUST UNITED AC 2011; 94:3-15. [PMID: 22125178 DOI: 10.1002/bdra.22869] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 09/09/2011] [Accepted: 09/12/2011] [Indexed: 01/12/2023]
Abstract
Bronchopulmonary dysplasia (BPD) is a chronic lung disease in infants born extremely preterm, typically before 28 weeks' gestation, characterized by a prolonged need for supplemental oxygen or positive pressure ventilation beyond 36 weeks postmenstrual age. The limited number of autopsy samples available from infants with BPD in the postsurfactant era has revealed a reduced capacity for gas exchange resulting from simplification of the distal lung structure with fewer, larger alveoli because of a failure of normal lung alveolar septation and pulmonary microvascular development. The mechanisms responsible for alveolar simplification in BPD have not been fully elucidated, but mounting evidence suggests that aberrations in the cross-talk between growth factors of the lung mesenchyme and distal airspace epithelium have a key role. Animal models that recapitulate the human condition have expanded our knowledge of the pathology of BPD and have identified candidate matrix components and growth factors in the developing lung that are disrupted by conditions that predispose infants to BPD and interfere with normal vascular and alveolar morphogenesis. This review focuses on the deviations from normal lung development that define the pathophysiology of BPD and summarizes the various candidate mesenchyme-associated proteins and growth factors that have been identified as being disrupted in animal models of BPD. Finally, future areas of research to identify novel targets affected in arrested lung development and recovery are discussed.
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Affiliation(s)
- Shawn K Ahlfeld
- Developmental Biology and Neonatal Medicine Program, H.B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana.
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Choi CW. Lung interstitial cells during alveolarization. KOREAN JOURNAL OF PEDIATRICS 2010; 53:979-84. [PMID: 21253310 PMCID: PMC3021730 DOI: 10.3345/kjp.2010.53.12.979] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Accepted: 11/30/2010] [Indexed: 02/01/2023]
Abstract
Recent progress in neonatal medicine has enabled survival of many extremely low-birth-weight infants. Prenatal steroids, surfactants, and non-invasive ventilation have helped reduce the incidence of the classical form of bronchopulmonary dysplasia characterized by marked fibrosis and emphysema. However, a new form of bronchopulmonary dysplasia marked by arrest of alveolarization remains a complication in the postnatal course of extremely low-birth-weight infants. To better understand this challenging complication, detailed alveolarization mechanisms should be delineated. Proper alveolarization involves the temporal and spatial coordination of a number of cells, mediators, and genes. Cross-talk between the mesenchyme and the epithelium through soluble and diffusible factors are key processes of alveolarization. Lung interstitial cells derived from the mesenchyme play a crucial role in alveolarization. Peak alveolar formation coincides with intense lung interstitial cell proliferation. Myofibroblasts are essential for secondary septation, a critical process of alveolarization, and localize to the front lines of alveologenesis. The differentiation and migration of myofibroblasts are strictly controlled by various mediators and genes. Disruption of this finely controlled mechanism leads to abnormal alveolarization. Since arrest in alveolarization is a hallmark of a new form of bronchopulmonary dysplasia, knowledge regarding the role of lung interstitial cells during alveolarization and their control mechanism will enable us to find more specific therapeutic strategies for bronchopulmonary dysplasia. In this review, the role of lung interstitial cells during alveolarization and control mechanisms of their differentiation and migration will be discussed.
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Affiliation(s)
- Chang Won Choi
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
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8
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Boucherat O, Benachi A, Barlier-Mur AM, Franco-Montoya ML, Martinovic J, Thébaud B, Chailley-Heu B, Bourbon JR. Decreased lung fibroblast growth factor 18 and elastin in human congenital diaphragmatic hernia and animal models. Am J Respir Crit Care Med 2007; 175:1066-77. [PMID: 17303798 DOI: 10.1164/rccm.200601-050oc] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Lung hypoplasia in congenital diaphragmatic hernia (CDH) seems to involve impaired alveolar septation. We hypothesized that disturbed deposition of elastin and expression of fibroblast growth factor 18 (FGF18), an elastogenesis stimulus, occurs in CDH. OBJECTIVES To document FGF18 and elastin in human CDH and ovine surgical and rat nitrofen models and to use models to evaluate the benefit of treatments. METHODS Human CDH and control lungs were collected post mortem. Diaphragmatic hernia was created in sheep at 85 days; fetal lungs were collected at 139 days (term = 145 days). Pregnant rats received nitrofen at 12 days; fetal lungs were collected at 21 days (term = 22 days). Some of the sheep fetuses with hernia underwent tracheal occlusion (TO); some of the nitrofen-treated pregnant rats received vitamin A. Both treatments are known to promote lung growth. MEASUREMENTS AND MAIN RESULTS Coincidental with the onset of secondary septation, FGF18 protein increased threefold in control human lungs, which failed to occur in CDH. FGF18 labeling was found in interstitial cells of septa. Elastin staining demonstrated poor septation and markedly decreased elastin density in CDH lungs. Consistently, lung FGF18 transcripts were diminished 60 and 83% by CDH in sheep and rats, respectively, and elastin density and expression were diminished. TO and vitamin A restored FGF18 and elastin expression in sheep and rats, respectively. TO restored elastin density. CONCLUSIONS Impaired septation in CDH is associated with decreased FGF18 expression and elastic fiber deposition. Simultaneous correction of FGF18 and elastin defects by TO and vitamin A suggests that defective elastogenesis may result, at least partly, from FGF18 deficiency.
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9
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Kilbride HW, Thibeault DW. Neonatal complications of preterm premature rupture of membranes. Pathophysiology and management. Clin Perinatol 2001; 28:761-85. [PMID: 11817188 DOI: 10.1016/s0095-5108(03)00076-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Midtrimester PROM is an infrequent, yet potentially disastrous complication of pregnancy. The most likely neonatal complication is preterm delivery with associated morbidity and mortality risks. Unique neonatal complications following PPROM include skeletal deformations and pulmonary hypoplasia related to prolonged oligohydramnios exposure. A systematic approach to an infant with respiratory insufficiency following PPROM delivery is possible with an understanding of the pathophysiology of pulmonary hypoplasia. Neonatal management should include immediate resuscitation including surfactant replacement, with careful attention to techniques of mechanical ventilation to avoid early volutrauma. Adjunctive therapies directed at pulmonary hypertension may now permit survival of some infants with less severe forms of pulmonary hypoplasia.
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MESH Headings
- Female
- Fetal Membranes, Premature Rupture/complications
- Fetal Membranes, Premature Rupture/physiopathology
- Humans
- Infant Care
- Infant, Newborn
- Infant, Newborn, Diseases/diagnosis
- Infant, Newborn, Diseases/etiology
- Infant, Newborn, Diseases/physiopathology
- Infant, Newborn, Diseases/therapy
- Infant, Premature
- Pregnancy
- Risk Factors
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Affiliation(s)
- H W Kilbride
- Department of Pediatrics, Section of Neonatal Medicine, Children's Mercy Hospitals and Clinics, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri, USA.
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Abstract
Pulmonary disorders in infants are intimately related to the pulmonary development during the antenatal, neonatal and infantile period. In this review, normal pulmonary development is considered and several pulmonary disorders such as pulmonary hypoplasia, pulmonary sequestration, congenital cystic adenomatoid malformation, hyaline membrane disease, bronchopulmonary dysplasia, Wilson-Mikity syndrome and perinatal pneumonia are presented in light of the current literature.
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Affiliation(s)
- Y Nakamura
- Department of Pathology, St Mary's Hospital, Kurume, Japan
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Haidar A, Ryder TA, Mobberley MA, Wigglesworth JS. Two techniques for electron opaque staining of elastic fibres using tannic acid in fresh and formalin fixed tissue. J Clin Pathol 1992; 45:633-5. [PMID: 1381384 PMCID: PMC495198 DOI: 10.1136/jcp.45.7.633] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Two electron microscopic staining techniques, one using tannic acid-glutaraldehyde as a fixative, and the other using tannic acid-uranyl acetate solution as a stain on ultra-thin sections of glutaraldehyde fixed material, were directly compared for elastic fibre staining on several human and animal tissues. Various concentrations of tannic acid were compared using both techniques. The two techniques were also compared on formalin fixed tissues. The use of tannic acid-uranyl acetate solution as a stain on processed tissue is by far the more consistent technique and achieves equally good results on glutaraldehyde or formalin fixed tissue. It is suggested that the use of the term tannic acid technique/method should be reserved for this particular method to achieve a meaningful interpretation of results in scientific papers.
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Affiliation(s)
- A Haidar
- Department of Histopathology, Royal Postgraduate Medical School, Hammersmith Hospital, London
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Haidar A, Ryder TA, Wigglesworth JS. Epithelial cell morphology and airspace size in hypoplastic human fetal lungs associated with oligohydramnios. PEDIATRIC PATHOLOGY 1991; 11:839-50. [PMID: 1775400 DOI: 10.3109/15513819109065481] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The relative frequency of different types of respiratory epithelial cells in normal fetal lungs (control, CON) and hypoplastic lungs associated with oligohydramnios (OH) was determined at the electron microscopic level and airspace size was measured. At 24+ weeks CON lungs had 82.4 +/- 1.2% undifferentiated cells, 15.9 +/- 1.2% type II cells, and 1.7 +/- 0.4% type I cells (n = 3), whereas OH lungs had 94.6 +/- 2.1% undifferentiated cells, 5.4 +/- 2.1% type II cells, and no type I cells (n = 3). At 36+ weeks CON lungs had 7.8 +/- 3.4% undifferentiated cells, 46.1 +/- 3.1% type II cells, and 46.1 +/- 1.4% type I cells (n = 3), whereas OH lungs had 37.7 +/- 1.2% undifferentiated cells, 42.5 +/- 1.7% type II cells, and 19.8 +/- 0.8% type I cells (n = 3). Differences between CON and OH lungs in the proportions of undifferentiated and type I cells at 36+ weeks were highly significant (p less than .001), whereas type II cell proportions did not differ significantly in either age group. The proportion of lung occupied by airspaces increased from 38.3% at 24+ weeks to 68.7% at 36+ weeks in CON lungs but only from 26.7% to 35.7% in OH lungs. The differences between the groups were significant at both 24+ weeks (p less than .01) and 36+ weeks (p less than .001). Mean airspace size in CON lungs varied from 2.8 x 10(-6) mm2 at 24+ weeks to 4.4 x 10(-6) mm2 at 36+ weeks and in OH lungs from 1.7 x 10(-6) mm2 at 24+ weeks to 2.7 x 10(-6) mm2 at 36+ weeks. These results give quantitative expression to the severity of impaired morphologic maturation in OH lungs.
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Affiliation(s)
- A Haidar
- Department of Histopathology, Royal Postgraduate Medical School, Hammersmith Hospital, London, England
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Haidar A, Ryder TA, Wigglesworth JS. Failure of elastin development in hypoplastic lungs associated with oligohydramnios: an electronmicroscopic study. Histopathology 1991; 18:471-3. [PMID: 1885168 DOI: 10.1111/j.1365-2559.1991.tb00881.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pulmonary hypoplasia associated with oligohydramnios results in delayed maturation of fetal lung as assessed at light microscope level. Using an elastin-specific electron-microscopic staining technique, we report absent elastic tissue development in the septal crests of these lungs even at term.
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Affiliation(s)
- A Haidar
- Department of Histopathology, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK
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