Researchers have developed a new method
that enables high-throughput screening of Huntingtons disease organoids.
Researchers from Rockefeller University,
US, have designed a novel generic phenotypic screening method at the organoid
level. Through this new method, the team discovered modulators of phenotypes of
Huntingtons disease, which could potentially be used therapeutically. The study
was recently published in Cell Reports Methods.
While organoids are promising tools for
modelling complex disease phenotypes, they often lack reproducibility and
scalability in their use of high-throughput screening assays. The
researchers therefore aimed to develop a method of using reproducible and scalable
micropatterned neural organoids for drug screening and to identify targets that
could rescue developmental phenotypes in organoids derived from stem cells that
carry mutations for Huntingtons disease.
In their report, the scientists explain
that although Huntingtons is a degenerative disease, it has recently been shown
to alter human neurodevelopment in human foetal samples. This therefore
suggests that early human organoid models that reproduce aberrant signalling
and morphogenesis in Huntingtons establish a promising approach for discovering
new mechanisms that are also relevant at later stages of the disease. To create
organoids mimicking the ectodermal compartment during human neurulation, the
researchers leveraged neuruloids that use micropattern-based differentiation,
with the possibility for easy upscaling while retaining excellent
reproducibility.
The team then performed a drug
discovery screen aimed at reversing a complex phenotype previously reported for
Huntingtons in the neuruloids, using a previously characterised isogenic series
of human embryonic stem cell lines with graded increases in CAG lengths, which
is a known cause of the neurodegenerative disease.
Finally, the team developed a deep-learning
computational pipeline to analyse the screening results and to quantify, for
each compound, its efficacy at reversing the disease phenotype back to normal
as well as its adverse effects. According to the report, this combination of
tools allowed the researchers to find that those specific bromodomain
inhibitors can efficiently revert Huntingtons phenotypes to wild type and
alleviate neuronal susceptibility to apoptosis in human Huntingtons neurons in
vitro, highlighting a potential new druggable target the condition that should
be further evaluated.
This study lays the groundwork for combining deep neural network and bioengineered human microtissues to carry out drug screens on neural organoids. This is achieved by the combination of a highly reproducible, scalable organoid platform allowing the easy generation of large image databanks required for leveraging the power of data analysis schemes based on deep neural networks, the researchers conclude in their paper.