Journal of Tissue Science and Engineering

Human Embryonic Stem Cell Lines BJNhem 19 and 20 Fail to Differentiate Into Lung Lineage Specific Cells despite Induction through Guided Endodermal Differentiation.

Abstract

Srabani Kar, Garima Hore, Niladitya Sanyal and Ena Ray Banerjee

Regenerative Therapy’s first and most critical requisite is the ex vivo synthesis of fully functional desired cells to replenish those lost by the body in a degenerative disease. The etiology of degeneration differs from disease to disease, likewise, strategies to regenerate lost tissue in its heterogeneousness, should also cater to the regeneration process and to customize the same, the researcher ought to devise strategies to repair or replace or regenerate in the appropriate spatio-temporal format. For example, in the inflammation-degeneration-induced pathophysiological situations of the respiratory epithelium, human embryonic stem cells have been used in a tissue engineering format to induce differentiation and amplification into the desired type of cell, in this case, the nonciliated squamous epithelial cells. To this end, we were given two human embryonic stem cell (hESC) lines and the main objective of our research work was to get BJNhem19 and BJNhem20 human embryonic stem cell (hESC) lines to differentiate into lung epithelial lineage–specific cells (i.e. alveolar epithelial type I and type II cells and clara cells) which are the key cells to degenerate in most degenerative lung ailments. This in order to generate a potentially unlimited supply of cells of the desired phenotype for use in a novel cell based therapy to repair lung injury. The strategy was to use guided endodermal differentiation by direct administration of one or more growth factors known to be involved in lung development in 2D cell cultures and characterize the cells for the desired markers. According to a tried strategy, the undifferentiated hESC were taken through embryoid body formation and then subjected to induction by defined growth factors in small airways growth medium and bronchiolar endothelial growth medium. Cells could not be grown feeder-free. Attempts to aid growth with combinations of extra cellular matrix plus defined medium (GeltrexR) as well as enriched media such as Matrigel and mTeSR1 did not yield satisfactory result. When grown on feeders also cell growth was again not optimum and practically none differentiated appreciably into the desired phenotype and maintained their pluripotent characters. After 5 days in induction media, they displayed fibroblast like features characterized by FACS. If cell lines are thus non-response to specific and guided endodermal induced differentiation, the obtained data is animportant information for cell repositories as numerous research labs screen various cell lines of embryonic origin with the specific aim to induce differentiation into a desired phenotype for functional translation into regenerative therapy. This study therefore fills an existing lacuna in available information regarding behavior of these two hESC available for work to the scientific world in several stem cell banks and shall prevent unnecessary and redundant further screening and save valuable resources.