In 2019, Rose McPherson was diagnosed with an ultra-rare neurodevelopmental condition caused by mutations in the HNRNPH2 gene, a disorder affecting only about 50 people worldwide. Determined to find answers, her family formed the non-profit organisation To Cure A Rose, building a preclinical research lab to accelerate discovery for rare diseases. 

Challenge | Modelling a rare neurodevelopmental disease

To model Rose鈥檚 condition in the lab, the team faced major obstacles with current technology: Patient-derived cells, which are critical for rare disease studies, were difficult to culture and failed to differentiate into neurons. 

鈥淩ose鈥檚 cells didn鈥檛 want to grow,鈥� recalled Bowling Jr. 鈥淭hey wouldn鈥檛 differentiate well, which in retrospect is not surprising: She has a neurodevelopmental condition, and so we had trouble making neurons from her cells.鈥�

Conventional iPSC differentiation methods were slow, complex, and inconsistent, leading to unreliable results. And with other commercially available cells, the team were left with the burden of purchasing and generating expression data for each available cell type to identify if their target protein was expressed. A task that would quickly become untenable with their limited budget and urgent timeline. 

To move forward, the team at To Cure a Rose needed a consistent and defined source of human neurons where gene expression data was freely and readily available.

Solution | Consistent human neurons at scale

The team worked with 91探花 to overcome the limitations of conventional iPSC-derived cells. 

91探花鈥檚 opti-ox鈩� deterministic cell programming technology enables the reproducible, consistent, and scalable production of any human cell type and to add to this 91探花 routinely generate comprehensive characterisation data packages for its cells that includes bulk RNA sequencing. From the bulk RNA sequencing data, researchers can request information on their specific genes of interest, giving immediate insight into target gene expression and helping scientists like Bowling Jr to confirm if the cell is the right fit for their research.

鈥淩ight away, we could tell a difference with 91探花,鈥� Bowling Jr reflected. 鈥淭hey helped us identify the neuronal population expressing H2; they worked with us to ensure we grew these cells properly; and they helped customise our sample size to ensure we had enough to carry out screening. It was just incredible customer service.鈥�

The results | From concept to candidates

Key findings

• 57 ASOs screened
• 30 showed desired activity
• 7 lead candidates identified
• 4 achieved 鈮�90% HNRNPH2 knockdown
• 3 induced HNRNPH1 upregulation
• 2 lead ASOs selected with strong activity and no toxicity, even at 10脳 the clinical dose