Basic Biology IV
Currently, approximately one child out of 100 suffers from autism or one of several autism-related diseases, clustered under the umbrella term autism spectrum disorders (ASD). Although described 70 years ago, very little is known about the causes of ASD and there is an urgent need to find biological tests that could help clinicians to unambiguously diagnose, at an early age, the various subtypes of ASD. In order to unveil the initial events that trigger brain mal-development, we chose to study the primordial cells, i.e. undifferentiated stem cells. We first collected one of the most accessible stem cells in the adult body, the nasal olfactory stem cell (OSC). We set up a bank of olfactory stem cells from 11 ASD patients and 11 age- and gender-matched healthy individuals and found a misexpression of a gene involved in neurotransmission. We propose now to go further on our journey in time by transforming OSCs into embryonic-like stem cells, named OSC-iPS. Using cutting edge molecular biology tools, we will compare both populations of stem cells, hoping to find new risk factor candidates. Then, we will turn OSC-iPS into neural stem cells (OSC-iPS-NSC) and then into neurons in order to assess the defects that altered the trajectories of the developing brain. If successful, this study should help to establish new molecular player(s) and potential biomarker(s) for a syndrome that greatly suffers from a lack of recognized molecular signatures.
Statement of Benefit to California:
According to the Autism in California 2012 Survey, "California continues to lead the nation in the highest number of individuals with Autism Spectrum Disorders (ASD)… there are at least 72,000 individuals living in California with a form of ASD." The rise in prevalence has dramatic incidence on family welfare but also on state budgets since California Governor Jerry Brown signed in 2009, a piece of legislation that will require health plans to include coverage for autism as a medical benefit. ASD treatments are costly, upwards of $70,000 a year. It is therefore of major importance to identify biomarkers for this syndrome, unveil some of the causes that trigger brain mal-development and, as a result, develop preventive treatments. The goals of our research program will address the underlying mechanisms for ASD and, in the long run, have potential for alleviating pain and suffering of the patient population and their families as well as decrease the financial burden to the patients’ families, private insurers and state agencies. Benefits will also accrue to California through technology transfer to California institutions. Our research program is likely to result in licensing of further technology to the corporate sector. This will have an impact on boosting the competitiveness of our state’s technology sector. Finally, because of the translational nature of the proposed research, our findings should have an impact on biotechnology and/or pharmaceutical companies in California.
This application proposes to study new biomarkers and risk factors for Autism Spectrum Disorders (ASD) using human nasal olfactory stem cells (OSCs) from ASD patients reprogrammed to induced pluripotent stem cells (iPSCs) and differentiated into neural stem cells (NSCs). The first aim is to generate iPSCs and NSCs from OSCs and perform whole-genome analyses. The second aim is to examine the function of a specific protein in OSCs and NSCs and their derivatives using genetic manipulation, multiple cellular assays and electrophysiology. The third aim is to knockdown candidate genes identified in aim one by lentiviral shRNA technology and examine their functions by assays used in aim two. Significance and Innovation - The rationale for using OSCs for comparative studies of OSC- iPSCs and OCS-iPSC-NSCs is not well justified. Reviewers noted that OSCs have not been shown to produce glutamatergic neurons, one of the major players involved in ASD, making them a poor model for studying this disease. - ASD is a significant unsolved health problem and the discovery of novel biomarkers could have a major impact on the field. - Reviewers were not convinced that sufficient statistical power would be obtained from the number of patients proposed to make strong conclusions about potential biomarkers of a sporadic disease such as ASD. Feasibility and Experimental Design - The proposal lacks sufficient consideration of the specific neuronal subtypes to be generated and their relevance in ASD. Reviewers noted that the proposed differentiation protocol gives rise to midbrain neurons, rather than the forebrain neurons thought to be primarily involved in ASD. - The rationale for focusing on a specific gene in aim two is not well justified, given that multiple dysregulated genes were identified in the preliminary data. - There is a general lack of discussion about alternative approaches and it is not clear how the results of genome-wide analyses in aim one will be prioritized for follow-up studies. Principal Investigator (PI) and Research Team - The PI is an outstanding investigator, with an excellent record of productivity in the iPSC field. - The Partner PI has generated much of the preliminary data on OSCs. Responsiveness to the RFA - The proposal is clearly responsive to the RFA by using human stem cells to address the disease mechanisms of ASD.