Stem Cell Therapy in Multiple Sclerosis

J. William Lindsey, MD

Feb. 13, 2008

Overview

             Introduction

             Very fashionable area, not my area of research or expertise

             What are the needs for treatment in MS?

             Where stem cells might help

             Background on stem cells

             Research results with stem cells relevant to MS

Treatment Needs in MS

             Stop the disease process and prevent new damage

             Know what causes MS

             Be able to stop the disease process

             Repair damaged tissue

             Repair damaged myelin

             Replace damaged nerve cells

Current Treatment—Interferon

Current Treatment—Glatiramer

What are stem cells?

             Stem cells are undifferentiated cells with the potential to divide indefinitely and differentiate into multiple different types of cell. 

Why Stem Cells?

             Stem cells can grow into any kind of cell

             Stem cells could repair damaged tissues such as myelin in MS

Types of Stem Cells

             Embryonic stem cells—derived from embryos, can become any type of cell

             Mesenchymal stem cells—found in bone marrow, can become some types of cells

             Neural stem cells—found in particular areas of the brain, can become nerve cells or glia

             Artificial stem cells—reprogrammed skin cells

Major Challenges

             If not derived from the person to be treated, they will be rejected as foreign

             Need the right quantity

             Have to get to the right place

             Need the right signals to turn into the right kind of cell

             New nerve cells have to make the right connections

             Need to know when to stop growing

Stem cells in animals

             Neural stem cells from periventricular zone grown in culture

             Injected into blood or ventricles of mice with acute EAE

             Cells migrated to damaged areas and survived

             Saw increase in new myelin and decrease in gliosis and axonal loss

             The mice were not as sick as untreated mice

             Nature 422:688

Other studies in animals

             Repair of chronic EAE with adult neural stem cells

             Transplanted cells secrete cytokines and neurotrophins but don’t differentiate

             Bone marrow derived stem cells may form myelin, or may fuse with myelin forming cells

             Embryonic stem cells cause tumors

Stem cells in humans

             4 Women who had bone marrow transplant from male donor

             Survival about 2 months

             Small numbers of donor-derived cells in the brain, both neurons and glia

Conclusions

             Stem cells may some day be useful for repair of damaged tissues in MS

             The underlying disease process needs to be stopped or stem cells will be futile

             The stem cells should be derived from the recipient

             Presently stem cells are all promise and no substance