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Sunitha Pulikkot
Department of Anatomy
College of Medicine and Health Sciences
Dissertation
Title
ESTABLISHMENT OF A 3D CULTURE MODEL OF GASTRIC STEM CELLS SUPPORTING THEIR DIFFER-
ENTIATION INTO MUCOUS CELLS USING MICROFIBROUS POLYCAPROLACTONE SCAFFOLD
Faculty Advisor
Prof Sherif Karam (CMHS), Dr Yaser Greish (COS), Prof Abdel-Hamid Mourad (COE)
Defense Date
13 May 2015
Abstract
In the stomach, epithelial stem cells are responsible for glandular homeostasis and perpetual production of four main
cell lineages secreting mucus, acid, pepsinogen and hormones. These stem cells could represent a source for cell
therapy or tissue engineering in cases of gastric mucosal damage. The aims of this study were 1) to manufacture
various forms of scaffolds using polycaprolactone, 2) to test the suitability of these scaffolds for growth of mouse gastric
stem (mGS) cells, and 3) to evaluate whether this culture system could tolerate exposure to acidic environment for
possible future applications. Three forms of polycaprolactone scaffold were fabricated: nonporous, microporous and
microfibrous. Microscopic examination and mechanical testing revealed some similarities between the microfibrous
scaffold and extracellular matrix of the stomach wall. Examination of mGS cells cultured on different forms of scaffold
revealed their preferential growth on microfibrous scaffolds with an initial increase in cell number followed by their
differentiation into gland mucous cells after 9 days. Various mechanical, chemical, morphological and molecular
examinations revealed that this 3D culture system could partially tolerate amoderate acidic environment. Interestingly,
only after 3-day culture at pH 5.5, mGS cells differentiated into mucous cells as demonstrated by binding of N-acetyl-
D-glucosamine-specific Griffonia simplicifolia II lectin and significant up-regulation of Spdef mRNA expression. In
conclusion, a 3D culture model of mGS cells supporting their differentiation into mucous cells has been established.
This study provides the basis for future use of stem cells in gastric tissue engineering for regenerative therapy of some
stomach diseases involving mucosal damage.
Keywords
: stem cell, gastric mucosa, cell differentiation, tissue engineering
Research Relevance and Potential Impact
Since stomach inflammation leading to ulcers and tumors are common health problems which require new therapeutic modalities, this study will
provide the basis for future use of stem cells and microfibrous scaffolds in tissue engineering for regenerative thera-py for some stomach diseases.
Relevant Publications
• Pulikkot P, Greish YE, Mourad AH, Karam SM (2014) Establishment of a three-dimensional culture system of gastric stem cells supporting mucous
cell differentiation using microfibrous polycaprolactone scaffolds. Cell Proliferation, 47:553-63.
• Pulikkot S, Greish YE, Mourad A-HI, Thomas SA, and Karam SM (2014) Evaluation of 3D culture model of gastric stem cells for tissue engineering.
Proceedings of the 8th Dubai International Conference for Medical Sciences, Dubai, UAE.
• Pulikkot S, Saseedharan P, Greish YE, Mourad A, Karam SM (2014) Growth and Differentiation of Gastric Stem Cells on Biodegradable Scaffolds.
Proceedings of the 3nd Biotechnology World Congress, Dubai, UAE.
• Pulikkot S, Greish YE, Karam SM (2012) Fabrication of nanofibrous scaffold for gastric epithelial tissue engineering. Proceedings of the International
Workshop on Advanced Material, Ras El-Khaimah, UAE.
Career Aspirations
This research inspires Sunitha to continue her career as a post-doctoral fellow and then to become an independent stem cell
scien-tist and an academician.