Researchers at Duke University, working in collaboration with Janssen Research & Development, LLC discovered that cells obtained from human umbilical cord tissue produce molecules that assist the growth, connectivity and survival of retinal neurons in rats. The findings point towards a certain family of molecules, known as the thrombospondins that might carry therapeutic potential for treating degenerative ailments of eyes.
“By understanding more about the working of these cells, we are one step closer to comprehending the diseased states of these cells and how they should be studied”, stated lead researcher Cagla Eroglu, Assistant Professor of Cell Biology and Neurobiology at the Duke University Medical Center.
Umbilical Stem Cells: The Secret Weapon Behind Neural Growth
Umbilical cord tissue-derived cells (hUTC) are different from cord blood cells – they are isolated directly from cord tissue. The researchers used an established cell culture system to see whether and how these cells could influence the growth of nerve cells obtained from retina of rat eyes. The two types of cells were bathed in the same fluid without physical contact.
It was observed that the retinal neurons formed new connections with each other known as synapses, and they also grew new ‘neurites’ (branches leading to additional connections). Furthermore, these cells survived longer than the retinal cells placed in a bath missing the umbilical cord tissue-derived cells.
This significantly demonstrated that something in the fluid surrounding the nerve cells containing the hUTCs was influencing neuronal growth. Via a series of experiments, large molecules called thrombospondin 1, 2 and 4, were discovered to be mainly responsible.
Proving The Hypothesis: Umbilical Stem Cells
Blocking thrombospondins was seen to reduce the formation of novel connections between nerve cells. Genetically inhibiting individual members of the thrombospondin family demonstrated that TSP1, TSP2, and TSP4 were primarily involved in developing the connections as well as the neurites.
“Thrombospondins had a significant effect on neurite outgrowth”, said Eroglu, a member of the Duke Institute for Brain Sciences (DIBS). “Making neurites and developing new connections between them is crucial for neuronal grown especially during injury and neurodegenerative diseases”.
However, blocking TSP1, TSP2 and TSP4 did not influence the survival of nerve cells. This suggests that certain other factors in the UTC cells must promote cell longevity. The research group is now searching for these molecules. The findings are published in the Journal of Neuroscience.