Use this URL to cite or link to this record in EThOS:
Title: The role of mechanotransduction in the regulation of human alveolar epithelial cell function
Author: Murray, Kathryn
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 2006
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
The aims of the study were i) to identify whether a reproducible protocol for isolation of type II pneumocytes from human lung tissue could be developed to study mechanical effects on these cells; ii) to establish whether an immortalised cell line, NCI-H441, expressed a phenotype similar to that of human type II pneumocytes, allowing its use in an in vitro model system of mechanotransduction; and iii) to investigate the effect of matrix substrate and mechanical stimulation on the production of inflammatory cytokines by NCI-H441. Human type II pneumocytes were successfully isolated from clinical resection samples, utilising a trypsin, DNase, discontinuous percoll gradient and differential attachment procedure.   Isolated cells were found to demonstrate blunt microvilli, abundant lamellar bodies characteristic of type II pneumocyte under electron microscopic evaluation. The percentage of the cell isolations positively identified as type II pneumocyte with the modified haematoxylin staining ranged from 26.50 – 71.35% of the total preparations. Many of the morphological and antigenic characteristics of type II pneumocytes were shared with the NCI-H441 cell line. A cyclic mechanical stimulation regime was applied to cells using an in house system with a regime of 20 minutes stimulation at 0.25 Hz, 5000 μstrain. Significant membrane hyperpolarisation responses were elicited in cyclin mechanical stimulated primary human type II pneumocytes seeded on fibronectin and NCI-H441 cells seeded on collagen IV and fibronectin. A significant membrane depolarisation response was demonstrated by NCI-H441 when seeded on bovine serum albumin. NCI-H441 cells express interleukins (IL) 4, 6 and 8, suppressor of cytokine signalling – 3 (SOCS3) and surfactant specific protein – A (SP-A).  Six hours after the application of cyclic mechanical stimulation NCI-H441 cells seeded on bovine albumin serum demonstrated a reduction in mean relative SOCS3 gene expression compared with controls. Cyclic mechanical stimulation of NCI-H441 cells seeded on fibronectin resulted in an increase in mean relative IL-8 gene expression levels an hour after stimulation.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available