Human-relevant, non-animal brain models recently made headlines at the Society for Neuroscience Annual Meeting, which was held in Washington, D.C., earlier this month. While we have been covering “mini-brain” models in Science First for some time, we are pleased to report that researchers continue to make improvements upon these valuable in vitro tools which can greatly expand our understanding of basic brain function, early brain development and disease.
One important use of the brain organoid model is to understand the effect of Zika viral infections. You may recall that being infected with the Zika virus during pregnancy has been linked to children being born with a serious birth defect known as microcephaly, in which infants are born with unusually small heads. The virus got a lot of media coverage last year, as the World Health Organization declared Zika a Public Health Emergency of International Concern and indicated that more research needed to be done to investigate and better understand the relationship between the virus and microcephaly.
While some researchers used animal models, including mice and nonhuman primates, to investigate Zika virus infections, others, including neuroscientist Dr. Guo-li Ming at the University of Pennsylvania, chose to work with brain organoids instead.
Dr. Ming and her lab have been growing organoids that are able to model specific brain regions, such as the forebrain, midbrain and hypothalamus. The lab recognized that organoids that model specific brain structures were better to work with than organoids modeling the whole brain, which were much more variable and challenging to control the growth of.
The cells used to create these three-dimensional brain organoids are grown in suspension inside custom-made spinning bioreactors that “mimic the microenvironment in the uterus,” according to Ming. And the forebrain organoids that are grown in these vessels mimic parts of human brain development “from conception to the first trimester.”
One main advantage of working with these brain organoids made from human cells is that they have human relevance. Ming noted that the organoids have many important human-specific traits, as the models reflect distinct cell layers found in the brain in addition to other more sophisticated structures.
We are encouraged to see researchers choosing to work with versatile and human-relevant brain organoids across many areas of research, and we look forward to the full potential of these continually-improving models being realized. These tools will make a tremendous contribution to science. They also hold the promise of reducing the use of animal models, which lack translational potential and may hinder progress in these important areas of research.
Source: Mika, A. “New and Improved Organoids Better Resemble Human Brains.” The Scientist. November 16, 2017.