Stem cell therapy in autism: recent insights

Stem Cell Secretions as a Potential Therapeutic Agent for Autism Spectrum Disorder: A Narrative Review

Autism spectrum disorder (ASD) is a neurodevelopmental illness characterized by impaired social interaction and restricted repetitive behaviors or interests. The rising prevalence of ASD diagnosis has triggered a surge in research into investigating the underlying neuropathological processes and finding new therapeutic approaches. ASD is characterized by neuroinflammation and dysregulation of neuro-immune cross-talk, which suggests that stem cell treatment might be a potential therapeutic approach. The beneficial and restorative effects of stem cells are mainly due to their paracrine activity, in which stem cells generate and release extracellular vesicles such as exosomes and distinct secreted non-vesicle soluble proteins, including, growth factors, chemokines, cytokines, and immunomodulatory molecules referred to as the Secretome. In this paper, we reviewed the existing research exploring the therapeutic potential of stem cell secretome focusing on their role in addressing ASD pathology. Furthermore, we proposed a comprehensive mechanism of action for stem cell secretions, encompassing the broader secretome as well as the specific contribution of exosomes, in alleviating ASD neuropathology. Across the reviewed studies, exosomes and secreted soluble factors of the transplanted stem cell demonstrate a potential efficacy in ameliorating autistic-like behaviors. The proposed mechanism of action involves the modulation of signaling pathways implicated in neuroinflammation, angiogenesis, cellular apoptosis, and immunomodulation.

Advances in the Treatment of Autism Spectrum Disorder: Current and Promising Strategies

Autism spectrum disorder (ASD) is an umbrella term for developmental disorders characterized by social and communication impairments, language difficulties, restricted interests, and repetitive behaviors. Current management approaches for ASD aim to resolve its clinical manifestations based on the type and severity of the disability. Although some medications like risperidone show potential in regulating ASD-associated symptoms, a comprehensive treatment strategy for ASD is yet to be discovered. To date, identifying appropriate therapeutic targets and treatment strategies remains challenging due to the complex pathogenesis associated with ASD. Therefore, a comprehensive approach must be tailored to target the numerous pathogenetic pathways of ASD. From currently viable and basic treatment strategies, this review explores the entire field of advancements in ASD management up to cutting-edge modern scientific research. A novel systematic and personalized treatment approach is suggested, combining the available medications and targeting each symptom accordingly. Herein, summarize and categorize the most appropriate ways of modern ASD management into three distinct categories: current, promising, and prospective strategies.

Undergraduate medical students' perceptions regarding stem cells: Is there a need for incorporating a stem cells elective course in the academic curriculum?

Stem cell therapy has recently progressed from the preclinical to the early clinical trial arena for a variety of diseases. Moreover, the medical students lack the deep and full understanding of its significance and potential as the promising future cure for diverse diseases worldwide. This study aims at evaluating the knowledge, awareness, and perception of medical students as far as stem cells applications are related in the medical field. A cross-sectional survey was carried out using online questionnaires, which were distributed via e-mail to cover all medical faculties in Jordan. The data show that medical students are supportive of using stem cells and their therapeutic applications, and most of them are willing and enthusiastically want to improve their knowledge about stem cells; however, due to the tight schedule and the lack of an elective course about stem cells in the curriculum, many of them are not ready to undergo further training in regenerative medicine unless it becomes part of the assigned training and part of the learning objectives for medical students. These findings indicated the need to update the medical school curriculum with new hits in medicine and expand the range of courses offered for medical students so they can be up-to-date with the quick advances in different medical disciplines.

Haste Makes Waste: There Is No Solid Evidence to Translate the Use of Stem Cells into Clinical Practice for Children with Autism Spectrum Disorder

Increasingly, private clinics around the world offer stem cell therapy as a therapeutic approach for autism spectrum disorder (ASD) [...].

Current Status of Mesenchymal Stem/Stromal Cells for Treatment of Neurological Diseases

Neurological disorders include a wide spectrum of clinical conditions affecting the central and peripheral nervous systems. For these conditions, which affect hundreds of millions of people worldwide, generally limited or no treatments are available, and cell-based therapies have been intensively investigated in preclinical and clinical studies. Among the available cell types, mesenchymal stem/stromal cells (MSCs) have been widely studied but as yet no cell-based treatment exists for neurological disease. We review current knowledge of the therapeutic potential of MSC-based therapies for neurological diseases, as well as possible mechanisms of action that may be explored to hasten the development of new and effective treatments. We also discuss the challenges for culture conditions, quality control, and the development of potency tests, aiming to generate more efficient cell therapy products for neurological disorders.

Stem Cell Transplantation Therapy and Neurological Disorders: Current Status and Future Perspectives

Neurodegenerative diseases are a global health issue with inadequate therapeutic options and an inability to restore the damaged nervous system. With advances in technology, health scientists continue to identify new approaches to the treatment of neurodegenerative diseases. Lost or injured neurons and glial cells can lead to the development of several neurological diseases, including Parkinson's disease, stroke, and multiple sclerosis. In recent years, neurons and glial cells have successfully been generated from stem cells in the laboratory utilizing cell culture technologies, fueling efforts to develop stem cell-based transplantation therapies for human patients. When a stem cell divides, each new cell has the potential to either remain a stem cell or differentiate into a germ cell with specialized characteristics, such as muscle cells, red blood cells, or brain cells. Although several obstacles remain before stem cells can be used for clinical applications, including some potential disadvantages that must be overcome, this cellular development represents a potential pathway through which patients may eventually achieve the ability to live more normal lives. In this review, we summarize the stem cell-based therapies that have been explored for various neurological disorders, discuss the potential advantages and drawbacks of these therapies, and examine future directions for this field.

Stem Cell Therapies for Cerebral Palsy and Autism Spectrum Disorder-A Systematic Review

Autism spectrum disorder (ASD) and cerebral palsy (CP) are some of the most common neurodevelopmental diseases. They have multifactorial origin, which means that each case may manifest differently from the others. In patients with ASD, symptoms associated with deficits in social communication and characteristic, repetitive types of behaviors or interests are predominant, while in patients with CP, motor disability is diagnosed with accompanying cognitive impairment of various degrees. In order to minimize their adverse effects, it is necessary to promptly diagnose and incorporate appropriate management, which can significantly improve patient quality of life. One of the therapeutic possibilities is stem cell therapy, already known from other branches of medicine, with high hopes for safe and effective treatment of these diseases. Undoubtedly, in the future we will have to face the challenges that will arise due to the still existing gaps in knowledge and the heterogeneity of this group of patients. The purpose of this systematic review is to summarize briefly the latest achievements and advances in stem cell therapy for ASD and CP.

Stem Cell Therapy in the Treatment of Patients With Autism Spectrum Disorder: a Systematic Review and Meta-analysis

OBJECTIVE

Assess the safety and efficacy of upcoming stem cell treatments and analyze their effects on the cognitive and behavioral impairments in patients diagnosed with autism.

METHODS

We included controlled and noncontrolled, randomized and non-randomized trials evaluating stem cell therapy as a treatment in patients with autism spectrum disorder compared to placebo or without comparator.

DATA SOURCES

Scopus, Web of Science, MEDLINE and EMBASE. Risk of bias was assessed using Cochrane's Risk of Bias tool and the NIH's Quality Assessment Tool for Studies With No Control Group.

RESULTS

Eleven trials including 461 patients proved eligible. ABC scale meta-analysis showed a mean raw of -11.97 in the intervention groups (95 % CI -91.45 to 67.52, p < 0.01). CARS scale reported a mean raw of -9.08 (95 % CI -15.43 to -2.73, p < 0.01). VABS scale was reported by their domains: communication domain reported a mean raw of 2.69 (95 % CI 1.30 to 4.08, p = 0.92); daily living domain, 1.99 (95 % CI 0.83 to 3.15, p = 0.51); motor domain, 1.06 (95 % CI -0.37 to 2.48, p = 0.20); socialization domain, 3.09 (95 % CI 1.71 to 4.48, p = 0.61); adaptive behavior domain, 2.10 (95 % CI 1.04 to 3.16, p = 0.36). Furthermore, the most common side effects reported included fever, hyperactivity, vomit, headache, and aggressiveness; no serious adverse events were reported.

CONCLUSIONS

The body of evidence suggests that stem cell therapy significantly improves scales in patients with autism spectrum disorder, hence, future studies should help us have more confidence in the results. We found no serious adverse events related to the stem cell therapy.

Intrathecal autologous bone marrow stem cell therapy in children with autism: A randomized controlled trial

INTRODUCTION

This study aimed to determine the safety and efficacy of treatment with autologous bone marrow mesenchymal stem cell (BMMSCs) compared with the routine treatment in children with autism spectrum disorder (ASD).

METHODS

In this ethically approved randomized controlled trial, 32 ASD children aged 5-15 years were randomly assigned to receive either autologous BMMSC plus rehabilitation therapy and risperidone (intervention group) or rehabilitation therapy and risperidone (control group). Autologous BMMSCs were intrathecally injected in the intervention group twice in 4 weeks. Patients were assessed using childhood autism rating scale (CARS), Gilliam autism rating scale-second edition (GARS-II), and clinical global impression (CGI) at the baseline, as well as 6 and 12 months after intervention.

RESULTS

Overall, 32 patients in two groups of intervention (n = 14) and control (n = 18) completed the study, of which 27 (84.4%) were male. Mean age was 9.50 ± 2.14 years. The improvements in CARS total score, GARS-II autism index, and CGI global improvement showed no significant differences between the groups over 12 months. However, the main effect for time*group interaction was significant regarding the CGI-severity of illness, showing a significantly more pronounced improvement in the intervention group (F = 6.719; P = .002).

DISCUSSION

Intrathecal injection of autologous BMMSCs seems to be safe and feasible, but has limited clinical efficacy in treatment of children with ASD.

Cell transplantation as a novel therapeutic strategy for autism spectrum disorders: a clinical study

BACKGROUND

Autism spectrum disorders [ASD] is a lifelong disability mainly affecting the development, communication, social interaction and behavior of an individual. Cell transplantation is emerging as a potential therapeutic strategy for ASD. Our previously published proof of concept study showed beneficial effects of cell transplantation in ASD. This study shows effect of cell transplantation in a larger sample size of ASD patients.

METHODS

254 patients diagnosed with ASD on DSM V criteria were enrolled in this open label non-randomized study. The intervention included intrathecal transplantation of autologous bone marrow mononuclear cells and neurorehabilitation. On mean follow up of 7.50 months, percentage analysis was performed on all symptomatic changes. Changes in outcome measures, Indian Scale for Assessment of Autism [ISAA] and Childhood Autism Rating Scale [CARS], were analyzed statistically using Wilcoxon Signed-Rank Test. Comparative analysis of Positron Emission Tomography [PET CT] scan brain, performed before and 6 months after intervention, was done in 86 patients to monitor the outcome at cellular level. Change in the standardized uptake values was statistically evaluated using T-Test [P≤0.05].

RESULTS

Improvements were observed in eye contact, attention and concentration, hyperactivity, sitting tolerance, social interaction, stereotypical behavior, aggressiveness, communication, speech, command following and self-stimulatory behavior. Statistically significant improvement was observed in scores of ISAA and CARS after intervention. A significantly better outcome of the intervention was found in patients at younger age and with shorter duration of disease [<5 years from time of diagnosis]. 86 patients who underwent a repeat PET CT scan showed improved brain metabolism after intervention in areas which correlated to the symptomatic changes. No major procedure related adverse events were recorded. However, 5 patients, with history of seizure and abnormal EEG, had an episode of seizure which was managed using medications. Outcome of intervention in these patients was not affected by seizures as improvements were observed in them.

CONCLUSION

The results of this study indicate that autologous bone marrow mononuclear cells in combination with neurorehabilitation are a safe and effective treatment modality for ASD. It improves the quality of life of patients and helps them to integrate in mainstream lifestyle.

Trends in Web Searches About the Causes and Treatments of Autism Over the Past 15 Years: Exploratory Infodemiology Study

BACKGROUND

Ninety percent of adults in the United States use the internet, and the majority of internet users report looking on the web for health information using search engines. The rising prevalence of autism spectrum disorder (ASD), uncertainty surrounding its etiology, and variety of intervention approaches contribute to questions about its causes and treatments. It is not known which terms people search most frequently about ASD and whether web search queries have changed over time. Infodemiology is an area of health informatics research using big data analytics to understand web search behavior.

OBJECTIVE

The objectives were to (1) use infodemiological data to analyze trends in web-based searches about the causes and treatments of ASD over time and (2) inform clinicians and ASD organizations about web queries regarding ASD.

METHODS

Google Trends was used to analyze web searches about the causes and treatments of ASD in the United States from 2004 to 2019. The search terms analyzed for queries about causes of ASD included vaccines, genetics, environmental factors, and microbiome and those for therapies included applied behavior analysis (ABA), gluten-free diet, chelation therapy, marijuana, probiotics, and stem cell therapy.

RESULTS

Google Trends results are normalized on a scale ranging from 0 to 100 to represent the frequency and relative interest of search topics. For searches about ASD causes, vaccines had the greatest frequency compared to other terms, with an initial search peak observed in 2008 (scaled score of 81), reaching the highest frequency in 2015 (scaled score of 100), and a current upward trend. In comparison, searches about genetics, environmental factors, and microbiome occurred less frequently. For web searches about ASD therapies, ABA consistently had a high frequency of search interest since 2004, reaching a maximum scaled score of 100 in 2019. The analyses of chelation therapy and gluten-free diet showed trending interest in 2005 (scaled score of 68) and 2007 (scaled score of 100), respectively, followed by a steady decline since (scaled scores of only 10 and 16, respectively, in 2019). Searches related to ASD and marijuana showed a rise in 2009 (scaled score of 35), and they continue to trend upward. Searches about probiotics and stem cell therapy have been relatively low (scaled scores of 22 and 18, respectively), but are gradually gaining interest. Web search volumes for stem cell therapy in 2019 surpassed both gluten-free diet and chelation therapy as web-searched interventions for ASD.

CONCLUSIONS

Google Trends is an effective infodemiology tool to analyze large-scale web search trends about ASD. The results showed informative variation in search trends over 15 years. These data are useful to inform clinicians and organizations about web queries on topics related to ASD, identify knowledge gaps, and target web-based education and knowledge translation strategies.

Beneficial Use and Potential Effectiveness of Physical Activity in Managing Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by poor social and communication skills. Therapeutic interventions are behavioral and educational—normally delivered as structured programs. Several well-established programs exist and most of them do not incorporate physical activity and exercise as core elements. Deficiencies in motor skills are associated with ASD and physical activity has been shown to reduce maladaptive behaviors with autistics. However, the notion of exercise being employed to manage autism is controversial. Meta-analysis and systematic reviews have concluded that physical activity has positive effects on social skills and behavior in young children and adolescents with autism. Activities such as martial arts have been singled out as being particularly beneficial. Established programs such as TEACCH have been successfully modified, as research trials, to be more physical activity-based and have shown positive results. Studies have also reinforced the importance of the role of parental involvement in delivering programs based on physical activity. There is a paucity of research evidence about the long-term effects of physical activity-based interventions. There is also disparity over the detailed nature of the activities and exercises that compose an effective program. Each person with autism has a highly individualized set of symptoms and characteristics for which highly individualized programs are warranted. This is especially true for physical activity programs.

Outcomes of bone marrow mononuclear cell transplantation combined with interventional education for autism spectrum disorder

The aim of this study was to evaluate the safety and efficacy of autologous bone marrow mononuclear cell transplantation combined with educational intervention for children with autism spectrum disorder. An open‐label clinical trial was performed from July 2017 to August 2019 at Vinmec International Hospital, Hanoi, Vietnam. Thirty children who fulfilled the autism criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and had Childhood Autism Rating Scale (CARS) scores >37 were selected. Bone marrow was harvested by anterior iliac crest puncture under general anesthesia. The volume collected was as follows: 8 mL/kg for patients under 10 kg (80 mL + [body weight in kg − 10] × 7 mL) for patients above 10 kg. Mononuclear cells were isolated with a Ficoll gradient and then infused intrathecally. The same procedure was repeated 6 months later. After the first transplantation, all patients underwent 8 weeks of educational intervention based on the Early Start Denver Model. There were no severe adverse events associated with transplantation. The severity of autism spectrum disorder (ASD) was significantly reduced, with the median CARS score decreasing from 50 (range 40‐55.5) to 46.5 (range 33.5‐53.5) (P < .05). Adaptive capacity increased, with the median Vineland Adaptive Behavior Scales score rising from 53.5 to 60.5. Social communication, language, and daily skills improved markedly within 18 months after transplantation. Conversely, repetitive behaviors and hyperactivity decreased remarkably. Autologous bone marrow mononuclear cell transplantation in combination with behavioral intervention was safe and well tolerated in children with ASD (Trial registration: ClinicalTrials.gov identifier: NCT03225651).

Stem Cell-Derived Exosomes in Autism Spectrum Disorder

Neurodevelopmental lifelong pathologies defined by problems with social interaction, communication capacity and presence of repetitive/stereotyped clusters of behavior and interests are grouped under the definition of autism spectrum disorder (ASD). ASD prevalence is still increasing, indicating the need to identify specific biomarkers and novel pharmacotherapies. Neuroinflammation and neuro-immune cross-talk dysregulation are specific hallmarks of ASD, offering the possibility of treating these disorders by stem cell therapy. Indeed, cellular strategies have been postulated, proposed and applied to ASD. However, less is known about the molecular action mechanisms of stem cells. As a possibility, the positive and restorative effects mediated by stem cells could be due to their paracrine activity, by which stem cells produce and release several ameliorative and anti-inflammatory molecules. Among the secreted complex tools, exosomes are sub-organelles, enriched by RNA and proteins, that provide cell-to-cell communication. Exosomes could be the mediators of many stem cell-associated therapeutic activities. This review article describes the potential role of exosomes in alleviating ASD symptoms.

Profiling parvalbumin interneurons using iPSC: challenges and perspectives for Autism Spectrum Disorder (ASD)

Autism spectrum disorders (ASD) are persistent conditions resulting from disrupted/altered neurodevelopment. ASD multifactorial etiology-and its numerous comorbid conditions-heightens the difficulty in identifying its underlying causes, thus obstructing the development of effective therapies. Increasing evidence from both animal and human studies suggests an altered functioning of the parvalbumin (PV)-expressing inhibitory interneurons as a common and possibly unifying pathway for some forms of ASD. PV-expressing interneurons (short: PVALB neurons) are critically implicated in the regulation of cortical networks' activity. Their particular connectivity patterns, i.e., their preferential targeting of perisomatic regions and axon initial segments of pyramidal cells, as well as their reciprocal connections, enable PVALB neurons to exert a fine-tuned control of, e.g., spike timing, resulting in the generation and modulation of rhythms in the gamma range, which are important for sensory perception and attention.New methodologies such as induced pluripotent stem cells (iPSC) and genome-editing techniques (CRISPR/Cas9) have proven to be valuable tools to get mechanistic insight in neurodevelopmental and/or neurodegenerative and neuropsychiatric diseases. Such technological advances have enabled the generation of PVALB neurons from iPSC. Tagging of these neurons would allow following their fate during the development, from precursor cells to differentiated (and functional) PVALB neurons. Also, it would enable a better understanding of PVALB neuron function, using either iPSC from healthy donors or ASD patients with known mutations in ASD risk genes. In this concept paper, the strategies hopefully leading to a better understanding of PVALB neuron function(s) are briefly discussed. We envision that such an iPSC-based approach combined with emerging (genetic) technologies may offer the opportunity to investigate in detail the role of PVALB neurons and PV during "neurodevelopment ex vivo."

Cell Therapy Targets for Autism Spectrum Disorders: Hopes, Challenges and Future Directions

Autism spectrum disorders as a group of pediatric neurodevelopmental diseases is a crucial part of the worldwide disabilities which have influence in communication skills, social interactions, and ability to understand the concepts. The precise pathophysiology of autism spectrum disorders due to the abundance of involved mechanisms is unknown. Some of these involved mechanisms are related to genetic factors, chronic neuro inflammation, mitochondrial dysfunction, oxidative stress, immune dysregulation, hormonal imbalance, and environmental factors. Current main treatments for autisms are behavioral, nutritional and medical therapies, however there is not definitive treatment approach. Therein, more novel therapies are still required to improve the symptoms. Several preclinical and clinical evidence were shown that stem cell therapy is a potential treatment option for autism spectrum disorders individuals. Considering the significant factors which can affect the outcome of stem cell therapeutic effects including stem cell types, route and dosage of administration, and mechanism of activity along with selecting best animal models can be very important in performing clinical trials.

Allogeneic Human Umbilical Cord Mesenchymal Stem Cells for the Treatment of Autism Spectrum Disorder in Children: Safety Profile and Effect on Cytokine Levels

Individuals with autism spectrum disorder (ASD) suffer from developmental disabilities that impact communication, behavior, and social interaction. Immune dysregulation and inflammation have been linked to children with ASD, the latter manifesting in serum levels of macrophage‐derived chemokine (MDC) and thymus, and activation‐regulated chemokine (TARC). Mesenchymal stem cells derived from umbilical cord tissue (UC‐MSCs) have immune‐modulatory and anti‐inflammatory properties, and have been safely used to treat a variety of conditions. This study investigated the safety and efficacy of UC‐MSCs administered to children diagnosed with ASD. Efficacy was evaluated with the Autism Treatment Evaluation Checklist (ATEC) and the Childhood Autism Rating Scale (CARS), and with measurements of MDC and TARC serum levels. Twenty subjects received a dose of 36 million intravenous UC‐MSCs every 12 weeks (four times over a 9‐month period), and were followed up at 3 and 12 months after treatment completion. Adverse events related to treatment were mild or moderate and short in duration. The CARS and ATEC scores of eight subjects decreased over the course of treatment, placing them in a lower ASD symptom category when compared with baseline. MDC and TARC inflammatory cytokine levels also decreased for five of these eight subjects. The mean MDC, TARC, ATEC, and CARS values attained their lowest levels 3 months after the last administration. UC‐MSC administration in children with ASD was therefore determined to be safe. Although some signals of efficacy were observed in a small group of children, possible links between inflammation levels and ASD symptoms should be further investigated. stem cells translational medicine2019;8:1008–1016