Harnessing the Power of Stem Cells: An Invention to Extract and Use Adult Stem Cells from Adult Neural Crest-Derived Tissues
Cells are the building blocks of all living things. They provide structure for the body, take in nutrients from food, and carry out other important functions. Cells also contain the body’s hereditary material and are able to make identical copies of themselves. There are over 200 different cell types in the human body, each specialized to carry out a particular function, or make up a particular tissue. The structure and organization of specialized cells, also called differentiated cells, vary to best suit their function.
Cells that are yet to be designated to a specific role are called stem cells. Stem cells have the remarkable potential to develop into many different cell types in the body during early life and growth. In addition, in many tissues they serve as a sort of internal repair system, dividing essentially without limit to replenish other cells as long as the person or animal is still alive.
“In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease,” says Herman S. Cheung, James Knight Professor in the University of Miami College of Engineering’s Department of Biomedical Engineering (BME). “Given their unique regenerative abilities, adult stem cells offer new potentials for treating diseases such as diabetes and heart disease.”
Historically, stem cell research has focused on embryonic – related to an unborn or unhatched offspring in the process of development – stem cells because they have the highest potential to differentiate into various tissue lineages. However, there are ethical dilemmas as well as immunological concerns arising from the use of embryonic cell sources in clinical settings.
Adult stem cells can avoid these issues; however, their potential to differentiate into diverse tissues is limited. “Scientists have been using these adult stem cells and ‘inducing’ them to differentiate into different cells, increasing their potential use, but the scientific community continues to work towards deciphering the underlying mechanisms of this ‘induction,’” explains Cheung.
Researchers have been working on the identification and isolation of remnant embryonic-like cells from adult tissues. One of the main focuses has been on tissues arising from the neural crest – a population of cells that originate from the neural folds during vertebrate development. They are important because they can differentiate into diverse cell lineages. One of these cell lineages gives rise to most dental tissues and is located near the roots of teeth, which is called periodontal ligament (PDL).
“Given their easy accessibility and differentiation potential, PDL derived stem cells could be an important cell source for regenerative medicine,” says Cheung. “However, there remains a need for improvement in the methods used for isolating these cell populations from the neural crest tissue – such as the periodontal ligament – as well as methods of conditioning these stem cells to differentiate into desired cell lineages for specific regenerative medicine applications.”
Herman Cheung, Daniel Pelaez, former PhD student of Cheung’s and currently an assistant professor of Ophthalmology at the University of Miami Bascom Palmer Eye Institute, and Charles Huang, associate professor in the College’s BME Department, recently published a patent on extracting and using stem cells from adult neural crest-derived tissues. Their invention is officially titled, “Isolation and Use of Pluripotent Stem Cell Populations from Adult Neural Crest-Derived Tissues.”
The invention is based, in part, on the discovery that a specific protein in humans can be used as a selection marker to extract a population of stem cells from neural crest tissue, such as the adult PDL. Consequently, the invention provides a method of selecting, isolating and using stem cells from neural crest-derived tissue in the repair of damaged tissues and the treatment of various degenerative diseases.
“Stem cells hold the potential to treat a wide range of diseases, some of which, right now, are uncurable,” says Cheung. “This invention gives us the exciting possibility to provide a renewable source of replacement cells for patients suffering from those diseases, opening the door for great impacts and improvements in human life.”