Epithelial ciliated beating cells essential for ex vivo ALI culture growth

Abstract

BackgroundBronchial epithelium plays a key role in orchestrating innate and adaptive immunity. The fate of ex vivo airway epithelial cultures growing at the air liquid interface (ALI) derived from human endobronchial biopsies or brushings is not easy to predict. Calibrating and differentiating these cells is a long and expensive process requiring rigorous expertise. Pinpointing factors associated with ALI culture success would help researchers gain further insight into epithelial progenitor behavior.MethodsA successful ALI culture was defined as one in which a pseudostratified epithelium has formed after 28 days in the presence of all differentiated epithelial cell types. A 4-year prospective bi-center study was conducted with adult subjects enrolled in different approved research protocols.Results463 consecutive endobronchial biopsies were obtained from normal healthy volunteers, healthy smokers, asthmatic patients and smokers with COPD. All demographic variables, the different fiber optic centers and culture operators, numbers of endo-bronchial biopsies and the presence of ciliated cells were carefully recorded. Univariate and multivariate models were developed. A stepwise procedure was used to select the final logistic regression model. ALI culture success was independently associated with the presence of living ciliated cells within the initial biopsy (OR = 2.18 [1.50–3.16], p < 0.001).ConclusionThis finding highlights the properties of the cells derived from the epithelium dedifferentiation process. The preferential selection of samples with ciliated beating cells would probably save time and money. It is still unknown whether successful ALI culture is related to indicators of general cell viability or a purported stem cell state specifically associated with ciliated beating cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s12890-017-0423-5) contains supplementary material, which is available to authorized users.

Temporal differentiation of bovine airway epithelial cells grown at an air-liquid interface

“…Ciliated cells increased in abundance until ~day 21 post-ALI, at which point most of the apical aspect of the cultures was composed of ciliated cells. The observed increase in the number of ciliated cells during prolonged culture at an ALI was expected because it has also been observed during differentiation of AECs from other species 27 , 39 , 55 , 74 , 75 . However, the density and uniformity of ciliation of fully differentiated BBEC cultures was generally less than that of ex vivo tissue (Fig.…”

Temporal differentiation of bovine airway epithelial cells grown at an air-liquid interface

“…This increase in the number of ciliated cells following culturing for several weeks at ALI has similarly been observed in human AECMs [31,32,58]. There was no variation in the population of ciliated cells at day 42 post-ALI (Fig 4D and E).…”

Mucus Microrheology Measured on Human Bronchial Epithelium Culture

“…In the past, rheological characterization of airway mucus has been restricted to sputum or mucus from dead mammals because rheology methods require large volumes of sample (mL) and because of the difficulty of collecting human bronchial mucus. Models of human bronchial epithelium (HBE) culture have been developed these last decades [2][3][4][5]. While these models have been validated by biological factors demonstrating, for various pathologies, that the phenotype is conserved, a few studies [6][7][8] describe the physical characteristics of these models and in particular the mucus flowing properties.…”