Establishment of Immortalized Primary Human Foreskin Keratinocytes and Their Application to Toxicity Assessment and Three Dimensional Skin Culture Construction

In spite of frequent usage of primary human foreskin keratinocytes (HFKs) in the study of skin biology, senescence-induced blockage of in vitro proliferation has been a big hurdle for their effective utilization. In order to overcome this passage limitation, we first isolated ten HFK lines from circumcision patients and successfully immortalized four of them via a retroviral transduction of high-risk human papillomavirus (HPV) E6 and E7 oncogenes. We confirmed expression of a keratinocyte marker protein, keratin 14 and two viral oncoproteins in these immortalized HFKs. We also observed their robust responsiveness to various exogenous stimuli, which was evidenced by increased mRNA expression of epithelial differentiation markers and pro-inflammatory genes in response to three reactive chemicals. In addition, their applicability to cytotoxicity assessment turned out to be comparable to that of HaCaT cells. Finally, we confirmed their differentiation capacity by construction of well-stratified three dimensional skin cultures. These newly established immortalized HFKs will be valuable tools not only for generation of in vitro skin disease models but also for prediction of potential toxicities of various cosmetic chemicals.

Immortalization of Primary Keratinocytes and Its Application to Skin Research

As a major component of the epidermal tissue, a primary keratinocyte has served as an essential tool not only for the study of pathogenesis of skin-related diseases but also for the assessment of potential toxicities of various chemicals used in cosmetics. However, its short lifespan in ex vivo setting has been a great hurdle for many practical applications. Therefore, a number of immortalization attempts have been made with success to overcome this limitation. In order to understand the immortalization process of a primary keratinocyte, several key biological phenomena governing its lifespan will be reviewed first. Then, various immortalization methods for the establishment of stable keratinocyte cell lines will be explained. Finally, its application to a three-dimensional skin culture system will be described.

SOLUCIONES TERAPÉUTICAS PARA LA RECONSTRUCCIÓN DE LA DERMIS Y LA EPIDERMIS. OPORTUNIDADES EN EL MEDIO ANTIOQUEÑO

En Antioquia, es necesario buscar una solución disponible, efectiva y económicamente viable para afrontar los problemas de la piel de los pacientes que, por accidentes o enfermedades, han disminuido su calidad de vida y se encuentran aislados a la espera de tratamientos que les permitan recuperar la funcionalidad de su cuerpo y les reduzcan los riesgos por la exposición de los tejidos internos. Las diferentes soluciones existentes en el mercado todavía no han llegado a superar algunos obstáculos tales como el cubrimiento de todas las extensiones, los altos costos, la funcionalidad de los tejidos restaurados, los rechazos de tipo inmune y la escasez de los sitios donantes. Este artículo presenta una revisión literaria que busca mostrar las diferentes alternativas de solución para pacientes con problemas de piel, dando énfasis en las soluciones clásicas aplicables y económicamente viables desde la ingeniería de tejidos en el sector antioqueño.

In Antioquia (Colombia), there are many patients who suffer dermal injuries caused by accident or disease. Therefore, it is necessary to pursue available, effective and affordable solutions to overcome dermal problems. Physicians and patients are both expecting corrective treatments that can reduce inner tissue exposition and allow the possibility of recovering skin functionality. Although there are many solutions for skin replacement, some obstacles remain, such as: high costs, limited availability of skin for implantation in extended areas, adequate functionality of the restored tissue and immunological rejection. Due to these issues, this article presents some of the existing alternative solutions for patients with skin injuries, considering the histology and physiology of the skin, and regarding the classical and economically attainable solutions to be used in Antioquia.