Abstract
Purpose :
Neurotech’s proprietary encapsulated cell therapy (ECT) drug product (NT-501) utilizes a genetically engineered cell line called NTC-201.6A based on retinal pigment epithelial cells to deliver ciliary neurotrophic factor (CNTF) to the retina to slow the progression of photoreceptor degradation in Macular Telangiectasia patients. While the device delivers CNTF, Neurotech wanted to characterize what other proteins and cytokines are released from NT-501 device using proteomic Mass Spectroscopy (MS) and cytokine multiplex. Therefore, an evaluation of the secreted proteins from NT-501 over the shelf-life was necessary.
Methods :
To evaluate other non-CNTF proteins and cytokines released by the NT-501 final drug product over stability and shelf life, Neurotech leveraged Eve Technologies’ (Calgary, CA) Human Cytokine/Chemokine 71-plex discovery assay array (HD71). Proteomic MS was conducted by MS Bio works to characterize the most abundant naturally secreted proteins from the CNTF expressing NT-501. Gene Ontology data was then used for functional identification of the secreted proteins.
Results :
A total of 746 protein ID hits were obtained from the MS at any measurable amount. Only a small subset of 33 proteins were observed throughout the shelf-life of the product in all replicates. As expected, CNTF was one of the highly detectable. Of the other 32 protein IDs, the majority were metabolic, structural, and adhesion proteins, indicative from the host cell line ARPE-19. The HD71 Multiplex assay is able to detect 71 different immunologically relevant chemokines, cytokines, and growth factors simultaneously for each sample. Only 6 were deemed to be appreciably detected across the shelf life.
Conclusions :
Neurotech extensively characterized other proteins secreted by the NT-501 final drug product, leveraging MS and Multiplex assays from two commercial contact research organizations. Of the detected secretory proteins by NT-501 across its shelf-life, many are commonly found in human retinal pigment epithelial (ARPE-19) cells. ARPE-19 cells are known to release structural/adhesion proteins and cytokines naturally in the eye, including IL-6, IL-8, MCP-1, PDGF, among others. As NT-501 parental cells derived from RPE cells, it is expected to share similar secreted proteins. The combination of Mass Spec and cytokine profiling can be used as a platform to monitor the maintenance of the secreted proteins.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.