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General Commentary ARTICLE

Front. Integr. Neurosci., 20 December 2011 | https://doi.org/10.3389/fnint.2011.00083

Cell-based neurorestorotherapy in amyotrophic lateral sclerosis – scientific truth should rely on facts, but not conjecture

Lin Chen1,2, Haitao Xi1,2 and Hongyun Huang1,2,3*
  • 1 Cell Research Center, Beijing Hongtianji Neuroscience Academy, Beijing, China
  • 2 Department of Neurosurgery, Beijing Rehabilitation Center, Beijing, China
  • 3 Division of Neurorestoratology, Yuquan Hospital, Tsinghua University, Beijing, China

A commentary on

No benefits from experimental treatment with olfactory ensheathing cells in patients with ALS
by Piepers, S., and van den Berg, L. H. (2010). Amyotroph. Lateral Scler. 11, 328–330.

Introduction

Amyotrophic lateral sclerosis (ALS) is a progressive, fatal, neurodegenerative disease caused by the degeneration of motor neurons, the nerve cells in the central nervous system that control voluntary muscle movement. Death due to respiratory failure occurs typically 2–5 years after disease onset (Suzuki et al., 2007). Our basic and clinical studies have proven that OECs have neuroprotective effect and can improve quality of life and prolong surviving time (Huang et al., 2007, 2008; Chen et al., 2007, 2012; Li et al., 2011). Dr. Piepers (Piepers and van den Berg, 2010) published a paper to make comment on our work, in which there were some wrong viewpoints and errors. Also there may be someone sharing same viewpoints with his paper. In order to avoid misleading readers, it is our irresistible duty to tell people the truth what happened about treatment study, show more evidences, and facts of development for this disease. Herein, we encourage people to read his original paper with our thoughts in mind. We strongly believe that scientific truth should rely on facts, but not conjecture.

“These Therapies Aim at Neuronal Replacement or Use Embryonic or Neuronal Stem Cells to Prevent Dysfunctional Motor Neurons From Dying” is Correct?

In fact, the mechanisms for neurorestoration in ALS are very complex, which lie on neural regeneration, repair, and replacement of damaged components of the nervous system, neuroplasticity, neuroprotection and neuromodulation, vasculogenesis, and recovery mechanisms of immune regulation (Fornai et al., 2008; IANR, 2009; Mitrecić et al., 2009; Huang et al., 2010). Embryonic or neuronal stem cells hardly replace motor neuron in ALS and also are difficult to have useful functions as people expect. Otherwise, transplanted cells can serve as a source of trophic factors providing neuroprotection, slowing down neuronal degeneration, and disease progression. Presently, cell–based neurorestorative treatment has become a new trend (Huang, 2010). Rapidly increasing worldwide data have proven that it has a pivotal therapeutic value in ALS (see Tables 1 and 2; Chen et al., 2012). So neruoprotection is one of the most functional neurorestorative strategies for ALS; unfortunately Dr. Piepers fully ignored most of the progress in this research field.

TABLE 1
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Table 1. Selected preclinical literatures of cell-based therapy for ALS (data from Pubmed; modified from 5).

TABLE 2
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Table 2. Literatures of cell-based therapy in ALS humans (data from Pubmed; modified from 5).

What Ideal Expectation of Treatment is and What Current Medicine Can Do for ALS?

To attenuate the rate of deterioration should be considered and encouraged as the main aim at the current time, because the cure has not yet been made available so far. So any improvement is very important for patients with ALS. Based on Dr. Piepers’ paper, we at least found three out of a total of seven patients who had reversed their functions after our treatment. Our recent study, multiple transplantations for ALS shows that every single treatment could make functional improvement for patients (Table 3; Chen et al., 2012). These essential findings should be translated as highlighted positive results because specialists in the ALS study community around the whole world know there is no way to reverse the clinical course of ALS through routine treatment including Rilutek. People should not require current medicine to get treatment results as their ideal expectation for some untreatable diseases such as ALS.

TABLE 3
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Table 3. Amyotrophic lateral sclerosis–FRS and Norris scale score and increased score after four treatments.

Where should the Cells be Transplanted into?

We can understand why Dr. Piepers said that “it is difficult to understand how focal injection of OECs into the corona radiata of ALS patients would result in improved function of motor neurons that are not in close proximity to the injection site.” We compared two ways by transplanting cells into spinal cord or brain; and there was no difference of functional improvement between two methods (Chen et al., 2007). We are also doing experimental study which will be published soon. People will know more about the progress in this field from our current experimental study, that is, OEC transplantation in corona radiate prolongs the survival of SOD1–G93A rats with protection to not only the upper motor neurons but lower motor neurons in cornu anterius medullae spinalis as well.

“It has been Shown that Injecting Stem Cells into the Spinal Cord of ALS Patients is Technically Feasible and Safe” is Correct?

It is well known that the spinal cord surgery under the general anesthesia has more risks in ALS patients, so we have improved our treatment from the initial intraspinal cord transplantation since over 5 years ago. Our clinical study proved that local anesthesia and stereotactic procedure has much less body damage for ALS patients than general anesthesia and open spinal surgery (Chen et al., 2007). We suggest that Dr. Piepers should do more clinical investigations or get clinical experience before he comments or discusses on which method is better, feasible, and safe for clinical issue.

Immunosuppressant is Necessary?

The application of immunosuppressant remains controversial after cell transplantation into the brain and/or spinal cord. In additional, some of the ALS patients are too weak to tolerate the drugs. Most recently, OECs were able to stay alive for at least 12–24 months which has been proven through two autopsies by Italian physicians (Giordana et al., 2010).

In summary, to talk by conjecture is a simple process; however, to really help patients with ALS to improve their neurological functions and quality of life must face hardships and challenges. The community should encourage any efforts to discover effective therapeutic strategies globally. Fortunately, now clinical studies already showed that cell therapy could restore patients’ neurological functions by neuroprotection or some other mechanisms.

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Citation: Chen L, Xi H and Huang H (2011) Cell-based neurorestorotherapy in amyotrophic lateral sclerosis – scientific truth should rely on facts, but not conjecture. Front. Integr. Neurosci. 5:83. doi: 10.3389/fnint.2011.00083

Received: 04 November 2011; Accepted: 29 November 2011;
Published online: 20 December 2011.

Copyright: © 2011 Chen, Xi and Huang. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.

*Correspondence: hongyunh@gmail.com