Neural Precursor Cells and Neuro-Regenerative Medicine

Introduction The central nervous system (CNS) of adults consists of cells of two different lines, nerve cells and glial cells. Neurons are the basic building blocks of the CNS and are responsible for communicating information through electrochemical mechanisms. Glial cells (astrocytes and oligodendrocytes) surround the neurons and they provide support and insulation. "There is no new neuron after birth" or "I can not reproduce the brain of an adult" is the doctrine of neuroscience in the last century (1). Recently, this principle has been challenged by NPCs found in the nervous system of embryos and adult mammals (1, 2).

Neural Progenitor Cells (NPC): As used herein, this refers to a mixed population of cells composed of all undifferentiated progeny of neural stem cells and therefore includes neural progenitors and neural stem cells. The term neural precursor cells is commonly used to generically describe a mixed population of NSCs and neural progenitor cells derived from embryonic stem cells and induced pluripotent stem cells. Prior to 1992, evidence of neurogenesis and limited in vitro proliferation of neural progenitor cells isolated from embryonic tissue in the presence of growth factors has been demonstrated in many reports 3-5. Groups, researchers can not convincingly demonstrate the characteristics of stem cells, ie self-renewal, expansion of proliferative capacity, and retention of the potential of multiple lines.

Neurobiologists often use various terms interchangeably to describe CNS undifferentiated cells. The most commonly used terms are "stem cell", "progenitor cell" and "progenitor cell". Inappropriate use of these terms to identify undifferentiated cells in the CNS led to confusion and misunderstanding in the field of NSC and neural progenitor cell research. However, these different types of undifferentiated cells in the CNS have different technical features and fate. For clarity, the terms used here are as follows.