Evolution of Movement Disorders in Patients With CLN2-Batten Disease Treated With Enzyme Replacement Therapy

Neuronal Ceroid Lipofuscinosis-Concepts, Classification, and Avenues for Therapy

Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative lysosomal storage disorders characterized by excessive accumulation of lysosomal lipofuscin. Thirteen subtypes of NCL have been identified, each associated with distinct genes encoding various transmembrane proteins, secretory proteins, or lysosomal enzymes. Clinically, NCL manifests in infants through vision impairment, motor and cognitive dysfunctions, epilepsy, and premature death. The pathological complexity of NCL has hindered the development of effective clinical protocols. Current treatment modalities, including enzyme replacement therapy, pharmacological approaches, gene therapy, and stem cell therapy, have demonstrated limited efficacy. However, emerging evidence suggests a significant relationship between NCL and microglial cells, highlighting the potential of novel microglial cell replacement therapies. This review comprehensively examines the pathogenic genes associated with various NCL subtypes, elucidating their roles, clinical presentations, and corresponding mouse models. Especially, we thoroughly discuss the advances in the clinical study of potential therapeutics, which crucially calls for early diagnosis and treatment more than ever.

Emerging Molecular-Genetic Families in Dystonia: Endosome-Autophagosome-Lysosome and Integrated Stress Response Pathways

Advances in genetic technologies and disease modeling have greatly accelerated the pace of introducing and validating molecular-genetic contributors to disease. In dystonia, there is a growing convergence across multiple distinct forms of the disease onto core biological processes. Here, we discuss two of these, the endosome-autophagosome-lysosome pathway and the integrated stress response, to highlight recent advances in the field. Using these two pathomechanisms as examples, we further discuss the opportunities that molecular-genetic grouping of dystonias present to transform dystonia care. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Psychometric Validation of the CLN2 Quality of Life Questionnaire in Participants with CLN2 Disease Treated with Cerliponase Alfa

OBJECTIVES

This study evaluated the psychometric properties of the ceroid lipofuscinosis type 2 Quality of Life (CLN2 QoL) questionnaire.

METHODS

Data from children with CLN2 disease aged 3-16 years receiving cerliponase alfa in the BMN 190-201 and BMN 190-202 clinical studies, collected via purposive sampling, were used to assess convergent and divergent validity, internal consistency and reliability. The clinically important difference (CID) was estimated with distribution- and anchor-based methods. Descriptive and inferential statistical analyses were conducted using IBM SPSS.

RESULTS

CLN2 QoL data of 22 participants were analysed. Ceiling effects were observed in 22 items (35% threshold); no floor effects were observed. Internal consistency analysis showed good reliability (Cronbach's alpha and Omega reliability >0.7) for four domains at study completion; only one domain had good reliability at baseline. All domains had good test-retest reliability (correlation >0.5) except Feeding With G-Tube and Seizures. Convergent and divergent correlation analysis showed moderate-strong correlations (>0.4) between PedsQL and CLN2 QoL total scores, between the Pediatric Quality of Life Inventory (PedsQL) total score and most CLN2 QoL domains at baseline, and between CLN2 QoL total score and most PedsQL domains at week 97. Known groups validity showed a significant difference in means for the Behaviour domain (p = 0.05) for reasons that could not be clarified. CID was 6.79-12.94 for domains; total score CID was 6.91 using distribution-based and 6.13-13.05 using anchor-based methods.

CONCLUSIONS

This study is the first to validate the CLN2 QoL and to estimate the CID of this instrument in CLN2 patients. Our results show good validity and reliability of this tool.