Intraspinal neural stem cell transplantation in amyotrophic lateral sclerosis: phase 1 trial outcomes.

OBJECTIVE: The US Food and Drug Administration-approved trial, "A Phase 1, Open-Label, First-in-Human, Feasibility and Safety Study of Human Spinal Cord-Derived Neural Stem Cell Transplantation for the Treatment of Amyotrophic Lateral Sclerosis, Protocol Number: NS2008-1," is complete. Our overall objective was to assess the safety and feasibility of stem cell transplantation into lumbar and/or cervical spinal cord regions in amyotrophic lateral sclerosis (ALS) subjects. METHODS: Preliminary results have been reported on the initial trial cohort of 12 ALS subjects. Here, we describe the safety and functional outcome monitoring results for the final trial cohort, consisting of 6 ALS subjects receiving 5 unilateral cervical intraspinal neural stem cell injections. Three of these subjects previously received 10 total bilateral lumbar injections as part of the earlier trial cohort. All injections utilized a novel spinal-mounted stabilization and injection device to deliver 100,000 neural stem cells per injection, for a dosing range up to 1.5 million cells. Subject assessments included detailed pre- and postsurgical neurological outcome measures. RESULTS: The cervical injection procedure was well tolerated and disease progression did not accelerate in any subject, verifying the safety and feasibility of cervical and dual-targeting approaches. Analyses on outcome data revealed preliminary insight into potential windows of stem cell biological activity and identified clinical assessment measures that closely correlate with ALS Functional Rating Scale-Revised scores, a standard assessment for ALS clinical trials. INTERPRETATION: This is the first report of cervical and dual-targeted intraspinal transplantation of neural stem cells in ALS subjects. This approach is feasible and well-tolerated, supporting future trial phases examining therapeutic dosing and efficacy.

Antecedent Disease is Less Prevalent in Amyotrophic Lateral Sclerosis.

BACKGROUND/AIMS: Recent studies suggest that antecedent disease could impact the pathophysiology of the motoneuron disease Amyotrophic Lateral Sclerosis (ALS). We performed a case-control study to examine the prevalence of 11 antecedent diseases in ALS. METHODS: Prevalence of antecedent disease in a 1,288 patient ALS population (Emory University ALS Clinic, Atlanta, Ga., USA) is compared to an age, gender, and geography-matched 7,561 subject control population using a statistical odds ratio (OR) with 95% confidence interval. RESULTS: Association of ALS with odds of arthritis (OR = 0.14); non-ALS neurological disease (OR = 0.14); liver disease (OR = 0.19); chronic obstructive pulmonary disorder or COPD (OR = 0.23); kidney disease (OR = 0.32); adult asthma (OR = 0.39); diabetes (OR = 0.47); hypertension (OR = 0.56); obesity (OR = 0.6); hyperlipidemia or hypercholesterolemia (OR = 0.62); and thyroid disease (OR = 0.78). CONCLUSIONS: The prevalence of antecedent disease was overall less in the ALS population. We present two potential lines of inquiry to explain these results: (1) 'Other disease as ALS protection'--antecedent diseases infer biochemical neuroprotection to ALS; (2) 'ALS as other disease protection'--the underpinnings of ALS could infer protection to other diseases, possibly via the mechanism hypervigilant regulation or 'too-high' regulatory feedback gains.

Lumbar intraspinal injection of neural stem cells in patients with amyotrophic lateral sclerosis: results of a phase I trial in 12 patients.

Advances in stem cell biology have generated intense interest in the prospect of transplanting stem cells into the nervous system for the treatment of neurodegenerative diseases. Here, we report the results of an ongoing phase I trial of intraspinal injections of fetal-derived neural stems cells in patients with amyotrophic lateral sclerosis (ALS). This is a first-in-human clinical trial with the goal of assessing the safety and tolerability of the surgical procedure, the introduction of stem cells into the spinal cord, and the use of immunosuppressant drugs in this patient population. Twelve patients received either five unilateral or five bilateral (10 total) injections into the lumbar spinal cord at a dose of 100,000 cells per injection. All patients tolerated the treatment without any long-term complications related to either the surgical procedure or the implantation of stem cells. Clinical assessments ranging from 6 to 18 months after transplantation demonstrated no evidence of acceleration of disease progression due to the intervention. One patient has shown improvement in his clinical status, although these data must be interpreted with caution since this trial was neither designed nor powered to measure treatment efficacy. These results allow us to report success in achieving the phase I goal of demonstrating safety of this therapeutic approach. Based on these positive results, we can now advance this trial by testing intraspinal injections into the cervical spinal cord, with the goal of protecting motor neuron pools affecting respiratory function, which may prolong life for patients with ALS.

Phosphorylated neurofilament heavy subunit (pNF-H) in peripheral blood and CSF as a potential prognostic biomarker in amyotrophic lateral sclerosis.

BACKGROUND: The phosphorylated neurofilament heavy subunit (pNF-H), a major structural component of motor axons, is a promising putative biomarker in amyotrophic lateral sclerosis (ALS) but has been studied mainly in CSF. We examined pNF-H concentrations in plasma, serum and CSF as a potential biomarker for disease progression and survival in ALS. METHODOLOGY: We measured pNF-H concentration by monoclonal sandwich ELISA in plasma (n=43), serum and CSF (n=20) in ALS patients collected at the Mayo Clinic Florida and Emory University. We included plasma from an ALS cohort (n=20) from an earlier pilot study in order to evaluate baseline pNF-H levels in relation to disease progression using the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R), survival and anatomical region of ALS onset. RESULTS: Higher pNF-H levels in plasma, serum and CSF showed evidence of association with faster decline in ALSFRS-R. There was evidence for a relationship of higher serum and plasma pNF-H levels with shorter survival, although evidence was weaker for CSF. pNF-H concentration in plasma (n=62) may be higher in patients with bulbar onset than in patients with spinal onset. CONCLUSIONS: In ALS, increased pNF-H concentration in plasma, serum and CSF appears to be associated with faster disease progression. Factors affecting pNF-H levels or their detection in serum and plasma in relation to disease course may differ from those in CSF. Data raising the possibility that site of ALS onset (bulbar vs spinal) may influence pNF-H levels in peripheral blood seems noteworthy but requires confirmation. These data support further study of pNF-H in CSF, serum and plasma as a potential ALS biomarker.

ALSUntangled #66: antimycobacterial antibiotics.

Several infections have been associated with motor neuron diseases resembling ALS, including species of viruses, bacteria, and parasites. Mycobacterium avium subspecies paratuberculosis (MAP), most known for its probable etiologic association with Crohn's disease, has been suggested as another possible infectious cause of motor neuron disease. Two published case reports describe the successful treatment of ALS-like symptoms with antimycobacterial antibiotics. Both cases had atypical features. Based on these, we believe it would be reasonable to begin performing chest imaging in PALS who have features of their history or exam that are atypical for ALS such as pain, fevers, or eye movement abnormalities. If the chest imaging is abnormal, more specific testing for mycobacteria may be indicated. Until there is more clear evidence of an association between mycobacteria and ALS, we cannot endorse the widespread use of potentially toxic antimycobacterial antibiotics for PALS.

Reduced expression of the Kinesin-Associated Protein 3 (KIFAP3) gene increases survival in sporadic amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis is a degenerative disorder of motor neurons that typically develops in the 6th decade and is uniformly fatal, usually within 5 years. To identify genetic variants associated with susceptibility and phenotypes in sporadic ALS, we performed a genome-wide SNP analysis in sporadic ALS cases and controls. A total of 288,357 SNPs were screened in a set of 1,821 sporadic ALS cases and 2,258 controls from the U.S. and Europe. Survival analysis was performed using 1,014 deceased sporadic cases. Top results for susceptibility were further screened in an independent sample set of 538 ALS cases and 556 controls. SNP rs1541160 within the KIFAP3 gene (encoding a kinesin-associated protein) yielded a genome-wide significant result (P = 1.84 x 10(-8)) that withstood Bonferroni correction for association with survival. Homozygosity for the favorable allele (CC) conferred a 14.0 months survival advantage. Sequence, genotypic and functional analyses revealed that there is linkage disequilibrium between rs1541160 and SNP rs522444 within the KIFAP3 promoter and that the favorable alleles of rs1541160 and rs522444 correlate with reduced KIFAP3 expression. No SNPs were associated with risk of sporadic ALS, site of onset, or age of onset. We have identified a variant within the KIFAP3 gene that is associated with decreased KIFAP3 expression and increased survival in sporadic ALS. These findings support the view that genetic factors modify phenotypes in this disease and that cellular motor proteins are determinants of motor neuron viability.

ALSUntangled #62: vitamin C.

Vitamin C is one of the most common supplements taken by people with ALS. As an antioxidant, it has a plausible mechanism for slowing disease progression and there are some flawed pre-clinical studies and case reports suggesting benefit. However, a small human trial showed no benefit. Given this negative trial, we do not currently advise vitamin C as an ALS treatment.

Gut microbiome differences between amyotrophic lateral sclerosis patients and spouse controls.

Objective: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that is incurable and ultimately fatal. Few therapeutic options are available to patients. In this study, we explored differences in microbiome composition associated with ALS. Methods: We compared the gut microbiome and inflammatory marker profiles of ALS patients (n = 10) to those of their spouses (n = 10). Gut microbiome profiles were determined by 16S rRNA gene sequencing. Results: The gut microbial communities of the ALS patients were more diverse and were deficient in Prevotella spp. compared with those of their spouses. In contrast, healthy couples (n = 10 couples of the opposite sex) recruited from the same geographic region as the patient population did not exhibit these differences. Stool and plasma inflammatory markers were similar between ALS patients and their spouses. Predictive analysis of microbial enzymes revealed that ALS patients had decreased activity in several metabolic pathways, including carbon metabolism, butyrate metabolism, and systems involving histidine kinase and response regulators. Conclusions: ALS patients exhibit differences in their gut microbial communities compared with spouse controls. Our findings suggest that modifying the gut microbiome, such as via amelioration of Prevotella spp. deficiency, and/or altering butyrate metabolism may have translational value for ALS treatment.

A novel ALS SOD1 C6S mutation with implications for aggregation related toxicity and genetic counseling.

In this report we describe an ALS family with a novel missense SOD1 mutation with substitution of serine for cysteine at the sixth amino acid (C6S). This mutation has interesting implications for the role of disulfides in causing disease. After identification of the ALS proband, we examined 17 members of an extended family and performed DNA mutation analysis on 21 family members. The level and activity of SOD1 in C6S carriers and wild-type family members was analyzed in erythrocytes. We found that the C6S mutation results in disease with an autosomal dominant mode of inheritance and markedly reduced penetrance. The S6 mutated protein demonstrates high stability relative to the C6 wild-type protein. The specific dismutation activity of S6 SOD1 is normal. In conclusion, C6S is a novel FALS associated mutation with reduced disease penetrance, long survival time and a phenotype very different from the other SOD1 mutations reported in codon C6. This mutation may provide insight into the role of SOD1 structural changes in disease.

Comparison of Phenotypic Characteristics and Prognosis Between Black and White Patients in a Tertiary ALS Clinic.

OBJECTIVE: To compare characteristics between Black and White patients with amyotrophic lateral sclerosis (ALS) in order to identify disparities and phenotypic variability. METHODS: We performed database review for patients seen between 1997 and 2020 at the Emory ALS Center in Atlanta, Georgia. Patients with ALS were included for analyses if race was self-reported as Black or White and symptom onset was prior to January 1, 2017. Variables examined include race, age at onset, diagnostic delay, site of onset, median income, C9orf72 mutation status, feeding tube and tracheostomy status, vital capacity, Amyotrophic Lateral Sclerosis Functional Rating Scale-revised(ALSFRS-R) score, and survival time. RESULTS: A total of 2,363 patient records were queried, and 1,298 were included in analysis; 203 self-identified as Black and 1,095 as White. Black patients had younger age at symptom onset, lower frequency of C9orf72 mutations, lower median income, longer diagnostic delay, and lower baseline ALSFRS-R and vital capacity compared to White patients. Black patients had a longer median survival than White patients; however, race was not an independent predictor of survival time when controlling for age at symptom onset, bulbar onset, and C9orf72 positivity. CONCLUSIONS: Black patients with ALS had longer median survival compared to White patients, but race was not independently associated with survival after controlling for age, site of onset, and C9orf72 status, factors known to predict prognosis. Black patients with ALS had longer diagnostic delay and lower baseline ventilatory and functional status at first clinic visit compared to White patients, which could be suggestive of barriers to tertiary care. Further studies are needed to identify the underlying causes of ALS racial differences.

Development and Validation of the Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS).

Importance: A new outcome measure for overall disability level with improved responsiveness is needed for amyotrophic lateral sclerosis (ALS) clinical trials. Objective: To describe the creation and development of a new self-reported ALS disability scale with improved item targeting and psychometric properties that used a mathematically rigorous Rasch methodology. Design, Setting, and Participants: A preliminary ALS disability questionnaire with 119 questions was created based on literature review, clinical judgement of an expert panel, and patient input. Patients with ALS were recruited from January 2017 to June 2019 from the Emory University and Atlanta VA Medical Center ALS clinics, both in Atlanta, Georgia, during regularly scheduled clinic appointments to complete the draft questionnaire and standard ALS outcome measures. All consecutive patients seen at the Emory University and Atlanta VA Medical Center ALS clinics during the recruitment period with a diagnosis of ALS who were able to provide informed consent were invited to participate in the study. Rasch analyses were performed, and items were systematically removed based on missing data, model fit, disordered thresholds, item bias, and clinical judgment. A total of 509 patients with ALS were seen at the 2 sites during the recruitment period, and 264 patients provided informed consent. Interventions: Participants completed the draft Rasch questionnaire and the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R). Main Outcomes and Measures: Rasch analyses and standard scale metrics were performed to create the new scale, and Rasch analyses were performed on the ALSFRS-R for comparison. Results: Overall, 243 participants with ALS completed the draft questionnaire, and 230 participants were included for Rasch analyses. The mean (SD) age for study participants was 61.9 (11.1) years, 146 (60.1%) were men, and site of onset was 23.0% bulbar (n = 56), 36.2% upper extremity (n = 88), and 39.5% lower extremity (n = 96). A 28-question Rasch-Built Overall ALS Disability Scale (ROADS) was constructed with each item scored 0, 1, or 2. The ROADS fulfilled Rasch model requirements, demonstrated improved item targeting compared with the ALSFRS-R, and had test-retest reliability of 0.97. Individual question fit statistics demonstrated infit values from 0.68 to 1.37 and outfit values from 0.66 to 1.43. The difference between the empirical variance explained by the measures and the modeled variance was 0.1%. The ALSFRS-R violated Rasch model expectations and demonstrated disordered thresholds for 9 of 12 questions; 13 of 48 answer choices on the ALSFRS-R were never the most probable answer choice for any overall disability level. Conclusions and Relevance: In this study, the 28-question, self-reported ROADS, which is linearly weighted, had improved item targeting compared with the ALSFRS-R, had high test-retest reliability, and was validated. ROADS may serve as a valuable and easily accessible outcome measure for use in ALS trials and in the clinic with improved responsiveness compared with the ALSFRS-R.

A common haplotype within the PON1 promoter region is associated with sporadic ALS.

Amyotrophic lateral sclerosis (ALS) is a progressive, neurodegenerative disorder of upper and lower motor neurons. Genetic variants in the paraoxonase gene cluster have been associated with susceptibility to sporadic ALS. Because these studies have yielded conflicting results, we have further investigated this association in a larger data set. Twenty SNPs spanning the paraoxonase gene cluster were genotyped on a panel of 597 case and 692 control samples and tested for association with risk of sporadic ALS and with ALS sub-phenotypes. Our study revealed two SNPs, rs987539 and rs2074351, within the paraoxonase gene cluster that are associated with susceptibility to sporadic ALS (uncorrected p=6.47E-04 and 7.87E-04, respectively). None of the 20 SNPs displayed significant associations with age of onset, site of onset or disease survival. Using a sliding window approach, we have also identified a 5-SNP haplotype that is significantly associated with risk of sporadic ALS (p=2.75E-05). We conclude that a common haplotype within the PON1 promoter region is associated with susceptibility to sporadic ALS.

Preventing familial amyotrophic lateral sclerosis: is a clinical trial feasible?

OBJECTIVE: To evaluate the feasibility of a clinical trial designed to delay or prevent the onset of disease amongst subjects at risk for familial amyotrophic lateral sclerosis (fALS). BACKGROUND: The success of many agents in prolonging survival in the SOD1 model of ALS has not been translated into effective therapies for patients with ALS. It is our hypothesis that a trial in fALS may reproduce the positive effects seen in fALS animals. METHODS: Pedigrees with at least two affected family members were constructed. Unaffected family members were assigned a risk status based on their relationship to affected subjects. Attitudes towards genetic testing were ascertained amongst the at-risk family members. RESULTS: We obtained data about 5,544 people (116 families) including 516 subjects with ALS (169 from SOD1 positive families) as well as 1,056 subjects "definitely" or "probably" at risk for fALS (335 from SOD1 positive families). In excess of 80% of subjects indicated an interest in participating in a future clinical trial directed at delaying the onset of the disease. Assuming the use of a therapeutic agent that will prolong the time to the onset of fALS by 50%, we estimate that a sample size of between 261 and 610 subjects 'definitely at risk' will be required (power 0.8) depending on whether patients are followed for 10 or 5 years respectively. CONCLUSIONS: A clinical trial in fALS may be feasible although such a trial would likely require prolonged follow-up and would require a therapeutic agent with a large clinical effect in order to be adequately powered.

Predicting disease progression in amyotrophic lateral sclerosis.

OBJECTIVE: It is essential to develop predictive algorithms for Amyotrophic Lateral Sclerosis (ALS) disease progression to allow for efficient clinical trials and patient care. The best existing predictive models rely on several months of baseline data and have only been validated in clinical trial research datasets. We asked whether a model developed using clinical research patient data could be applied to the broader ALS population typically seen at a tertiary care ALS clinic. METHODS: Based on the PRO-ACT ALS database, we developed random forest (RF), pre-slope, and generalized linear (GLM) models to test whether accurate, unbiased models could be created using only baseline data. Secondly, we tested whether a model could be validated with a clinical patient dataset to demonstrate broader applicability. RESULTS: We found that a random forest model using only baseline data could accurately predict disease progression for a clinical trial research dataset as well as a population of patients being treated at a tertiary care clinic. The RF Model outperformed a pre-slope model and was similar to a GLM model in terms of root mean square deviation at early time points. At later time points, the RF Model was far superior to either model. Finally, we found that only the RF Model was unbiased and was less subject to overfitting than either of the other two models when applied to a clinic population. INTERPRETATION: We conclude that the RF Model delivers superior predictions of ALS disease progression.

Comparative analysis of C9orf72 and sporadic disease in an ALS clinic population.

OBJECTIVE: We investigated whether the C9orf72 expansion mutation in patients with amyotrophic lateral sclerosis (ALS) is associated with unique demographic and clinical features. METHODS: Between 2001 and 2015, approximately half of all patients attending the Emory ALS Clinic agreed to donate DNA for research. This research cohort of 781 patients was screened for the C9orf72 expansion, and demographic and clinical data were compared between those with and without the C9orf72 mutation. For mutation carriers without a family history of ALS, we sought further family history of dementia and other non-ALS neurodegenerative diseases in first-degree relatives. RESULTS: The C9orf72 expansion was identified in 61 patients (7.8%). Compared to those without the expansion mutation, these patients did not differ in race, age, or site of onset. As expected, C9orf72 patients were more likely to have a family history of ALS (59% vs 7.9%) and to present with comorbid frontotemporal dementia (FTD) (14.8% vs 1.7%). Survival was shorter in patients with the expansion (log-rank χ(2)[1] = 45.323, p < 0.001). Further investigation in 28 patients initially categorized as having no known family history of ALS identified a family history of dementia in 16 cases; 6 of these had characteristics suggestive of FTD. CONCLUSIONS: Comparing the C9orf72 ALS population to the general ALS population, there were no differences in race, age at onset, or proportion of patients with bulbar onset disease. Differences identified in patients with the C9orf72 mutation included shortened survival and an equal proportion of men and women. In addition, we found that assessing family history for dementia may identify other family members likely to be carrying the C9orf72 expansion, reduce the number of sporadic cases, and thus increase our understanding of disease penetrance.

Transplantation of spinal cord-derived neural stem cells for ALS: Analysis of phase 1 and 2 trials.

OBJECTIVE: To test the safety of spinal cord transplantation of human stem cells in patients with amyotrophic lateral sclerosis (ALS) with escalating doses and expansion of the trial to multiple clinical centers. METHODS: This open-label trial included 15 participants at 3 academic centers divided into 5 treatment groups receiving increasing doses of stem cells by increasing numbers of cells/injection and increasing numbers of injections. All participants received bilateral injections into the cervical spinal cord (C3-C5). The final group received injections into both the lumbar (L2-L4) and cervical cord through 2 separate surgical procedures. Participants were assessed for adverse events and progression of disease, as measured by the ALS Functional Rating Scale-Revised, forced vital capacity, and quantitative measures of strength. Statistical analysis focused on the slopes of decline of these phase 2 trial participants alone or in combination with the phase 1 participants (previously reported), comparing these groups to 3 separate historical control groups. RESULTS: Adverse events were mostly related to transient pain associated with surgery and to side effects of immunosuppressant medications. There was one incident of acute postoperative deterioration in neurologic function and another incident of a central pain syndrome. We could not discern differences in surgical outcomes between surgeons. Comparisons of the slopes of decline with the 3 separate historical control groups showed no differences in mean rates of progression. CONCLUSIONS: Intraspinal transplantation of human spinal cord-derived neural stem cells can be safely accomplished at high doses, including successive lumbar and cervical procedures. The procedure can be expanded safely to multiple surgical centers. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with ALS, spinal cord transplantation of human stem cells can be safely accomplished and does not accelerate the progression of the disease. This study lacks the precision to exclude important benefit or safety issues.

NEK1 variants confer susceptibility to amyotrophic lateral sclerosis.

To identify genetic factors contributing to amyotrophic lateral sclerosis (ALS), we conducted whole-exome analyses of 1,022 index familial ALS (FALS) cases and 7,315 controls. In a new screening strategy, we performed gene-burden analyses trained with established ALS genes and identified a significant association between loss-of-function (LOF) NEK1 variants and FALS risk. Independently, autozygosity mapping for an isolated community in the Netherlands identified a NEK1 p.Arg261His variant as a candidate risk factor. Replication analyses of sporadic ALS (SALS) cases and independent control cohorts confirmed significant disease association for both p.Arg261His (10,589 samples analyzed) and NEK1 LOF variants (3,362 samples analyzed). In total, we observed NEK1 risk variants in nearly 3% of ALS cases. NEK1 has been linked to several cellular functions, including cilia formation, DNA-damage response, microtubule stability, neuronal morphology and axonal polarity. Our results provide new and important insights into ALS etiopathogenesis and genetic etiology.

Genome-wide association analyses identify new risk variants and the genetic architecture of amyotrophic lateral sclerosis.

To elucidate the genetic architecture of amyotrophic lateral sclerosis (ALS) and find associated loci, we assembled a custom imputation reference panel from whole-genome-sequenced patients with ALS and matched controls (n = 1,861). Through imputation and mixed-model association analysis in 12,577 cases and 23,475 controls, combined with 2,579 cases and 2,767 controls in an independent replication cohort, we fine-mapped a new risk locus on chromosome 21 and identified C21orf2 as a gene associated with ALS risk. In addition, we identified MOBP and SCFD1 as new associated risk loci. We established evidence of ALS being a complex genetic trait with a polygenic architecture. Furthermore, we estimated the SNP-based heritability at 8.5%, with a distinct and important role for low-frequency variants (frequency 1-10%). This study motivates the interrogation of larger samples with full genome coverage to identify rare causal variants that underpin ALS risk.

CCNF mutations in amyotrophic lateral sclerosis and frontotemporal dementia.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are overlapping, fatal neurodegenerative disorders in which the molecular and pathogenic basis remains poorly understood. Ubiquitinated protein aggregates, of which TDP-43 is a major component, are a characteristic pathological feature of most ALS and FTD patients. Here we use genome-wide linkage analysis in a large ALS/FTD kindred to identify a novel disease locus on chromosome 16p13.3. Whole-exome sequencing identified a CCNF missense mutation at this locus. Interrogation of international cohorts identified additional novel CCNF variants in familial and sporadic ALS and FTD. Enrichment of rare protein-altering CCNF variants was evident in a large sporadic ALS replication cohort. CCNF encodes cyclin F, a component of an E3 ubiquitin-protein ligase complex (SCF(Cyclin F)). Expression of mutant CCNF in neuronal cells caused abnormal ubiquitination and accumulation of ubiquitinated proteins, including TDP-43 and a SCF(Cyclin F) substrate. This implicates common mechanisms, linked to protein homeostasis, underlying neuronal degeneration.

Intraspinal stem cell transplantation in amyotrophic lateral sclerosis: a phase I trial, cervical microinjection, and final surgical safety outcomes.

BACKGROUND: The first US Food and Drug Administration approved clinical trial for a stem cell-based treatment of amyotrophic lateral sclerosis has now been completed. OBJECTIVE: Primary aims assessed the safety of a direct microinjection-based technique and the toxicity of neural stem cell transplantation to the ventral horn of the cervical and thoracolumbar spinal cord. Results from thoracolumbar-only microinjection groups have been previously published. Cervical and cervical plus thoracolumbar microinjection group perioperative morbidity results are presented. METHODS: Eighteen microinjection procedures (n = 12 thoracolumbar [T10/11], n = 6 cervical [C3-5]) delivered NSI-566RSC (Neuralstem, Inc), a human neural stem cell, to 15 patients in 5 cohorts. Each injection series comprised 5 injections of 10 µL at 4-mm intervals. The patients in group A (n = 6) were nonambulatory and received unilateral (n = 3) or bilateral (n = 3) thoracolumbar microinjections. The patients in groups B to E were ambulatory and received either unilateral (group B, n = 3) or bilateral (group C, n = 3) thoracolumbar microinjection. Group D and E patients received unilateral cervical (group D, n = 3) or cervical plus bilateral thoracolumbar microinjection (group E, n = 3). RESULTS: Unilateral cervical (group D, n = 3) and cervical plus thoracolumbar (group E, n = 3) microinjections to the ventral horn have been completed in ambulatory patients. One patient developed a postoperative kyphotic deformity prompting completion of a laminoplasty in subsequent patients. Another required reoperation for wound dehiscence and infection. The solitary patient with bulbar amyotrophic lateral sclerosis required perioperative reintubation. CONCLUSION: Delivery of a cellular payload to the cervical or thoracolumbar spinal cord was well tolerated by the spinal cord in this vulnerable population. This encouraging finding supports consideration of this delivery approach for neurodegenerative, oncologic, and traumatic spinal cord afflictions.