Cell transplantation: stem cells and precursor cells

Neuroinflammation Quantification for Spinal Cord Injury

Spinal cord injury (SCI) leads to irreversible devastating neurological disabilities. Accumulated evidence in the literature indicates that the inflammatory response that occurs in the spinal cord following injury contributes importantly to spread tissue damage to healthy regions adjacent to the lesion site, and consequently, to increase neurological deficits. Therefore, targeting inflammation could lead to the development of new therapies to prevent tissue damage and neurological impairments after SCI. Inflammation is regulated, in part, by the expression of pro-inflammatory and anti-inflammatory cytokines synthesized, mainly, by glial cells. Hence, methodologies that could ease the quantification of multiple cytokines and immune cells from spinal cord tissue samples are needed to assess the potential of new anti-inflammatory therapies. In the present unit, we describe how to induce contusion injuries in the mouse spinal cord, as well as, two useful methodologies to assess neuroinflammation in lesioned spinal cord tissue samples. © 2018 by John Wiley & Sons, Inc.

Human neural progenitors derived from integration-free iPSCs for SCI therapy

As a potentially unlimited autologous cell source, patient induced pluripotent stem cells (iPSCs) provide great capability for tissue regeneration, particularly in spinal cord injury (SCI). However, despite significant progress made in translation of iPSC-derived neural progenitor cells (NPCs) to clinical settings, a few hurdles remain. Among them, non-invasive approach to obtain source cells in a timely manner, safer integration-free delivery of reprogramming factors, and purification of NPCs before transplantation are top priorities to overcome. In this study, we developed a safe and cost-effective pipeline to generate clinically relevant NPCs. We first isolated cells from patients' urine and reprogrammed them into iPSCs by non-integrating Sendai viral vectors, and carried out experiments on neural differentiation. NPCs were purified by A2B5, an antibody specifically recognizing a glycoganglioside on the cell surface of neural lineage cells, via fluorescence activated cell sorting. Upon further in vitro induction, NPCs were able to give rise to neurons, oligodendrocytes and astrocytes. To test the functionality of the A2B5+ NPCs, we grafted them into the contused mouse thoracic spinal cord. Eight weeks after transplantation, the grafted cells survived, integrated into the injured spinal cord, and differentiated into neurons and glia. Our specific focus on cell source, reprogramming, differentiation and purification method purposely addresses timing and safety issues of transplantation to SCI models. It is our belief that this work takes one step closer on using human iPSC derivatives to SCI clinical settings.

Lineage, fate, and fate potential of NG2-glia

NG2 cells represent a fourth major glial cell population in the mammalian central nervous system (CNS). They arise from discrete germinal zones in mid-gestation embryos and expand to occupy the entire CNS parenchyma. Genetic fate mapping studies have shown that oligodendrocytes and a subpopulation of ventral protoplasmic astrocytes arise from NG2 cells. This review describes recent findings on the fate and fate potential of NG2 cells under physiological and pathological conditions. We discuss age-dependent changes in the fate and fate potential of NG2 cells and possible mechanisms that could be involved in restricting their oligodendrocyte differentiation or fate plasticity. This article is part of a Special Issue entitled SI:NG2-glia(Invited only).

Spinal cord injury - there is not just one way of treating it

In the last century, research in the field of spinal cord trauma has brought insightful knowledge which has led to a detailed understanding of mechanisms that are involved in injury- and recovery-related processes. The quest for a cure for the yet generally incurable condition as well as the exponential rise in gained information has brought about the development of numerous treatment approaches while at the same time the abundance of data has become quite unmanageable. Owing to an enormous amount of preclinical therapeutic approaches, this report highlights important trends rather than specific treatment strategies. We focus on current advances in the treatment of spinal cord injury and want to further draw attention to arising problems in spinal cord injury (SCI) research and discuss possible solutions.