HootOwl
Member
So after digging a little deeper into the Frequency Therapeutics paper I think I can conclude with confidence that they did in fact produce IHC as well as OHC in their animal models. I know this has been brought up as a concern before.
Quote 1:
Hair cell colonies were either negative or positive for prestin, a motor protein located in the membrane of outer hair cells, identifying a subset of the differentiated cells as outer hair cells. Colonies of new hair cells also expressed vesicular glutamate transporter3 (vGlut3), an inner hair cell marker, which was only found in colonies that did not express prestin"
Quote 2:
"Our differentiation conditions thus generated inner and outer cochlear hair cell types that contained components of synaptic specializations, the transduction apparatus receptors, and ion channels of hair cells"
Quote 3:
"There was a highly significant (p < 0.001) ∼2-fold increase in myosin VIIa+ inner and outer hair cells after 3 days of drug treatment as compared to control cochlea."
You can see the newly regenerated IHC and OHC here. Myosin VIIa is the bio marker stain used to identify a new hair cell. The arrows are pointing to the existence of supporting cells after trans differentiation.
And finally you also have this graph, which also shows the increase in IHC, followed by this caption.
(B) Increased numbers of inner hair cells, outer hair cells, and total hair cells (IHCs, OHCs, and total HCs) were observed in treated as compared to control cochleae by myosin VIIa (Myo VIIa) expression. n = 4 each. Error bars represent mean ± SD; ∗∗∗p < 0.001.
Unless I'm completely misreading everything here I think if anyone is concerned about IHC regeneration then you should be okay based on the data here (if it translates into humans).
Quote 1:
Hair cell colonies were either negative or positive for prestin, a motor protein located in the membrane of outer hair cells, identifying a subset of the differentiated cells as outer hair cells. Colonies of new hair cells also expressed vesicular glutamate transporter3 (vGlut3), an inner hair cell marker, which was only found in colonies that did not express prestin"
Quote 2:
"Our differentiation conditions thus generated inner and outer cochlear hair cell types that contained components of synaptic specializations, the transduction apparatus receptors, and ion channels of hair cells"
Quote 3:
"There was a highly significant (p < 0.001) ∼2-fold increase in myosin VIIa+ inner and outer hair cells after 3 days of drug treatment as compared to control cochlea."
You can see the newly regenerated IHC and OHC here. Myosin VIIa is the bio marker stain used to identify a new hair cell. The arrows are pointing to the existence of supporting cells after trans differentiation.
And finally you also have this graph, which also shows the increase in IHC, followed by this caption.
(B) Increased numbers of inner hair cells, outer hair cells, and total hair cells (IHCs, OHCs, and total HCs) were observed in treated as compared to control cochleae by myosin VIIa (Myo VIIa) expression. n = 4 each. Error bars represent mean ± SD; ∗∗∗p < 0.001.
Unless I'm completely misreading everything here I think if anyone is concerned about IHC regeneration then you should be okay based on the data here (if it translates into humans).