Summary: Scientists have developed a new surgical method that allows two retinal tissue grafts to be implanted in one eye, advancing treatment strategies for macular degeneration (AMD) related to dry age. This new approach allows graft test side by side, one with epithelial retinal pigment cells (RPE) and another without the same lesion, using a clamp specially designed to maintain eye pressure and reduce damage.
In animal models, RPE grafts significantly retained photoreceptors to detect light and regenerated the choriocapillaris, the layer of blood vessels essential for the health of the retina. These results improve continuous efforts to translate stem cells cultivated in laboratory into clinical treatments for vision loss.
Key facts:
Dual graft innovation: A new technique allows the simultaneous implementation of two grafts for a better comparative analysis.
Source: NIH
The scientists of the National Health Institutes (NIF) have developed a new surgical technique to implement multiple tissue grafts in the eye retina.
Animal findings can help advance treatment options for dry macular degeneration related to age (AMD), which is a main cause of loss of vision among major Americans.
A report on the technique published today in JCI Insight.
In diseases such as AMD, light -sensitive retinal fabric in the back of the Degenera eye. Scientists are testing therapies to restore damaged retains with fabric grafts cultivated in the patient -derived stem cell laboratory.
Until now, surgeons have only been able to place an graft in the retina, limiting the area that can be treated in patients and the ability to make side comparisons on animal models.
These comparisons are crucial to confirm that tissue grafts are being integrated with the retina and the underlying blood supply of a network of small blood vessels known as Coriocapillary.
For the technique, the researchers designed a new surgical clamp that maintains eye pressure during the insertion of two tissue patches in immediate succession while minimizing damage to the surrounding tissue.
In animal models, scientists used their recently designed surgical technique to compare two different grafts placed sequentially in the same lesion similar to experimentally induced AMD. An graft consisted of retinal pigment epithelial cells (RPE) grown in a biodegradable scaffolding. RPE cells admit and nourish photoreceptors for retinal light detection.
In AMD, vision loss occurs together with the loss of RPE and photoreceptors cells. In the laboratory, RPE cells are grown from human blood cells after they have become stem cells. The second graft consisted only of the biodegradable scaffolding to serve as control.
After surgery, scientists used artificial intelligence to analyze retinal images and compare the effects of each graft. They observed that the RPE grafts promoted the survival of the photoreceptors, while the photoreceptors near the grafts only of scaffolding died at a much higher speed.
In addition, they were able to confirm for the first time that the RPE graft also regenerated the choriocapillaris, which provides the retina oxygen and nutrients.
The findings expand in the demonstrated capacity in an ongoing clinical trial in human in the first in human grafts derived from the patient for the dry form of AMD.
Financing: The work was supported by the intramural research program of the National Institute of Eye
On this research news of visual neuroscience and AMD
Author: NIH Communications Office
Source: NIH
Contact: NIH Communications Office – NIH
Image: The image is accredited to Neuroscience News
Original research: open access.
“The IPSC-RPE patch retains photoreceptors and regenerates coriocapillaris in a degeneration model of the external pork regina” by Kapil Bharti et al. JCI Insight
Abstract
The IPSC-RPE patch retains photoreceptors and regenerates coriocapillaris in a degeneration model of the exterior pork regina
Dry macular degeneration (AMD) related to age is a main cause of non -treatable vision loss. In advanced cases, the loss of epithelium cells of the retinal pigment (RPE) occurs together with the degeneration of the photoreceptor and the coriocapillaris.
We presume that a patch would mitigate the degeneration of photoreceptors and coriocapillary to restore vision.
A RPE patch derived from induced pluripotent stem cells (IRPE) was developed using a clinically compatible manufacturing process by maturation of IRPE cells in a poli scaffold (lactic-co-glycolic acid) (plga).
To compare the results, we develop a surgical procedure for the immediate sequential delivery of Plga-Irpe patches and/or only plga in the subbrectinal space of a degeneration pork model of the laser-induced external retina.
The segmentation of the optical coherence image tomography based on the deep learning algorithm (OCT) Verified segmentation of photoreceptors on the areas of the retina transplanted by PLAGA-IIRPE and not in the laser retina or only with plga-transplant.
The adaptive optics images of individual cone photoreceptors further supported this finding. Oct Angiography revealed the regeneration of Coriocapillaris in Plga-Irpe, and not in retinas translated only by Plga.
Our data, obtained using clinically relevant techniques, verified that PLGA-IRPE admits the survival of photoreceptors and regenerates the coriocapillary in a pork retina with laser lesas.
The sequential delivery of two 8 mm2 transplants allows the surgical viability and double dose safety test. This work allows surgery to treat larger and non -adjoining retinal degeneration areas.
