视神经中保护视力的干细胞可能会为失明带来新的治疗方案

2020/9/15 15:56:02 本站原创 佚名 【字体:

Stem cells in optic nerve that preserve vision may lead to new therapeutic strategy for blindness

视神经中保护视力的干细胞可能会为失明带来新的治疗方案

 

廖联明  编译

 

Researchers at the University of Maryland School of Medicine (UMSOM) have for the first time identified stem cells in the region of the optic nerve, which transmits signals from the eye to the brain. The finding, published this week in the journal Proceedings of the National Academy of Sciences (PNAS), presents a new theory on why the most common form of glaucoma may develop and provides potential new ways to treat a leading cause of blindness in American adults.

马里兰大学医学院(UMSOM)的研究人员首次在视神经区域发现了干细胞,该区域将信号从眼睛传递到大脑。本周发表在《美国国家科学院院刊》(PNAS)上的一项研究发现,提出了一种新的理论,解释了最常见的青光眼类型是如何发生的,并为治疗造成美国成年人失明的主要病因提供了潜在新的治疗方法。

 

"We believe these cells, called neural progenitor cells, are present in the optic nerve tissue at birth and remain for decades, helping to nourish the nerve fibers that form the optic nerve," said study leader Steven Bernstein, MD, PhD, Professor of the Department of Ophthalmology and Visual Sciences at the University of Maryland School of Medicine. "Without these cells, the fibers may lose their resistance to stress, and begin to deteriorate, causing damage to the optic nerve, which may ultimately lead to glaucoma."

研究负责人、马里兰大学医学院眼科和视觉科学系教授、医学博士Steven Bernstein说:我们认为,这些被称为神经前体的细胞,在出生时就存在于视神经组织中,并存在数十年,有助于滋养形成视神经的神经纤维。如果没有这些细胞,神经纤维可能无法应对应激,并开始恶化,对视神经造成损害,最终可能导致青光眼。

 

More than 3 million Americans have glaucoma, which results from damage to the optic nerve, causing blindness in 120,000 U.S. patients. This nerve damage is usually related to increased pressure in the eye due to a build up of fluid that does not drain properly. Blind spots can develop in a patient's visual field that gradually widen over time.

超过300万美国人患有青光眼,这是由于视神经受损引起的,导致12万美国患者失明。这种神经损伤是由于积聚的液体不能正常排出,使眼内压力增高有关。失明的区域可能会在患者的视野中恶化,并随着时间的推移逐渐扩大。

 

This is the first time that neural progenitor cells have been discovered in the optic nerve. Without these cells, the nerve is unable to repair itself from damage caused by glaucoma or other conditions. This may lead to permanent vision loss and disability. The presence of neural stem/progenitor cells opens the door to new treatments to repair damage to the optic nerve, which is very exciting news."

这是首次在视神经中发现神经前体细胞。没有这些细胞,神经就无法从青光眼或其他疾病造成的损伤中进行自我修复。这可能会导致永久性失明和神经损伤。神经干细胞/前体细胞的出现为修复视神经损伤的新疗法打开了大门,这是非常令人兴奋的消息。

 

To make the research discovery, Dr. Bernstein and his team examined a narrow band of tissue called the optic nerve lamina. Less than 1 millimeter wide, the lamina lies between the light-sensitive retina tissue at the back of the eye and the optic nerve. The long nerve cell fibers extend from the retina through the lamina, into the optic nerve. What the researchers discovered is that the lamina progenitor cells may be responsible for insulating the fibers immediately after they leave the eye, supporting the connections between nerve cells on the pathway to the brain.

为了进行这项研究,Bernstein博士和他的团队检查了名为视神经薄层的窄带组织。薄层不到1毫米宽,位于眼睛后部对光敏感的视网膜组织和视神经之间。长长的神经细胞纤维从视网膜延伸到视神经薄层,进入视神经。研究人员发现,在神经纤维一旦走出眼睛后,依赖薄层前体细胞和周围组织隔离,保障大脑的神经细胞之间的连接。

 

The stem cells in the lamina niche bathes these neuron extensions with growth factors, as well as aiding in the formation of the insulating sheath. The researchers were able to confirm the presence of these stem cells by using antibodies and genetically modified animals that identified the specific protein markers on neuronal stem cells.

薄层中的干细胞用生长因子滋润这些神经元延伸部分,并有助形成绝缘鞘。研究人员能够通过使用抗体和转基因动物来确认这些干细胞的存在,这些抗体能够识别神经元干细胞上的特定蛋白标记物。

 

"It took 52 trials to successfully grow the lamina progenitor cells in a culture," said Dr. Bernstein, "so this was a challenging process." Dr. Bernstein and his collaborators needed to identify the correct mix of growth factors and other cell culture conditions that would be most conducive for the stem cells to grow and replicate. Eventually the research team found the stem cells could be coaxed into differentiating into several different types of neural cells. These include neurons and glial cells, which are known to be important for cell repair and cell replacement in different brain regions.

Bernstein博士说:经过52次试验,成功地在培养液中培养了薄层前体细胞,因此这是一个充满挑战的过程。” Bernstein博士和他的合作者需要找出生长因子和细胞培养的其他条件的正确方式,这将最有利于干细胞的生长和复制。最终,研究小组发现干细胞可以被诱导分化为几种不同类型的神经细胞。 这些包括神经元和神经胶质细胞,它们对于不同大脑区域的细胞修复和更新很重要。

 

This discovery may prove to be game-changing for the treatment of eye diseases that affect the optic nerve. Dr. Bernstein and his research team plan to use genetically modified mice to see how the depletion of lamina progenitor cells contributes to diseases such as glaucoma and prevents repair.

这一发现可能会改变影响视神经的眼疾治疗的方式。Bernstein博士和他的研究团队计划使用转基因小鼠来观察薄层前体细胞的耗竭如何导致青光眼等疾病并阻止其修复。

 

Future research is needed to explore the neural progenitors repair mechanisms. If we can identify the critical growth factors that these cells secrete, they may be potentially useful as a cocktail to slow the progression of glaucoma and other age-related vision disorders.

神经前体细胞的修复机制还需要进一步的研究。如果我们能确定这些细胞分泌的关键生长因子,它们可能会作为一种综合疗法,来减缓青光眼和其他与年龄相关的视力障碍的恶化。

 

"This exciting discovery could usher in a sea change in the field of age-related diseases that cause vision loss," said E. Albert Reece, MD, PhD, MBA, Executive Vice President for Medical Affairs, UM Baltimore, and the John Z. and Akiko K. Bowers Distinguished Professor and Dean, University of Maryland School of Medicine. "New treatment options are desperately needed for the millions of patients whose vision is severely impacted by glaucoma, and I think this research will provide new hope for them."

巴尔的摩医学事务执行副总裁、医学博士、工商管理硕士E.Albert Reece和马里兰大学医学院杰出教授兼院长John Z.Akiko K.Bowers说:这一令人兴奋的发现可能会给与年龄相关的失明疾病领域带来巨大的变化。数百万视力受到青光眼严重影响的患者迫切需要新的治疗方案,我认为这项研究将为他们带来新的希望。

 

 

Journal Reference:

 

S. L. Bernstein, Y. Guo, C. Kerr, R. J. Fawcett, J. H. Stern, S. Temple, Z. Mehrabian. The optic nerve lamina region is a neural progenitor cell niche. Proceedings of the National Academy of Sciences, 2020; 202001858 DOI: 10.1073/pnas.2001858117

 

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