B细胞产物或在MS的进展中发挥重要作用
2012-08-04 18:37:08   来源：37度医学网   作者：  评论：0 点击：

Wayne State University School of Medicineresearchers, working with colleagues in Canada, have found that one or moresubstances produced by a type of immune cell in people with multiple sclerosis(MS) may play a role in the disease's progression. The finding could lead tonew targeted therapies for MS treatment.

韦恩州立大学的研究者们与加拿大的同事合作，发现在多发性硬化（MS）患者体内的一种免疫细胞可能产生一种或多种物质，这些物质在疾病的进展中发挥了作用。这项发现可能为MS的治疗提供新的靶点。

B cells, said Robert Lisak, M.D., professorof neurology at Wayne State and lead author of the study, are a subset oflymphocytes (a type of circulating white blood cell) that mature to become plasmacells and produce immunoglobulins, proteins that serve as antibodies. The Bcells appear to have other functions, including helping to regulate otherlymphocytes, particularly T cells, and helping maintain normal immune functionwhen healthy.

韦恩州立大学神经病学教授、本研究的第一作者Robert Lisak博士说，B细胞作为一种淋巴细胞（血液循环中的白细胞之一），成熟后变为浆细胞并产生免疫球蛋白，免疫球蛋白是能够起到抗体作用的蛋白质。B细 胞还具有其他功能，包括帮助调节其他淋巴细胞，尤其是T细胞，并能够帮助维持健康人体正常的免疫功能。

In patients with MS, the B cells appear toattack the brain and spinal cord, possibly because there are substancesproduced in the nervous system and the meninges - the covering of the brain andspinal cord - that attract them. Once within the meninges or central nervoussystem, Lisak said, the activated B cells secrete one or more substances thatdo not seem to be immunoglobulins but that damage oligodendrocytes, the cellsthat produce a protective substance called myelin.

在MS患者中，B细胞攻击大脑和脊髓，可能是因为中枢神经系 统和脑膜（大脑和脊髓的被膜）中产生的物质吸引了B细胞。Lisak说，一旦活化的B细胞进入脑膜或中枢神经系统内，就会分泌一种或多种貌似不是免疫球蛋 白但会损伤少突胶质细胞的物质，少突胶质细胞能够产生一种具有保护性的叫做“髓鞘”的物质。

The B cells appear to be more active in patientswith MS, which may explain why they produce these toxic substances and, inpart, why they are attracted to the meninges and the nervous system.

在MS患者中，B细胞表现得更为活跃，这也许可能解释为何它们产生了这些毒性物质，也可能部分解释为何它们被吸引到脑膜和神经系统。

The brain, for the most part, can bedivided into gray and white areas. Neurons are located in the gray area, andthe white parts are where neurons send their axons - similar to electricalcables carrying messages - to communicate with other neurons and bring messagesfrom the brain to the muscles. The white parts of the brain are white becauseoligodendrocytes make myelin, a cholesterol-rich membrane that coats the axons.The myelin's function is to insulate the axons, akin to the plastic coating onan electrical cable. In addition, the myelin speeds communication along axonsand makes that communication more reliable. When the myelin coating is attackedand degraded, impulses - messages from the brain to other parts of the body -can "leak" and be derailed from their target. Oligodendrocytes alsoseem to engage in other activities important to nerve cells and their axons.

脑的绝大部分可以被分为 白质和灰质。神经元位于灰质，白质是神经元发出轴突与其他神经元联络并将信息由脑传递到肌肉的区域，轴突与传输信息的电缆类似。脑的白质之所以是白色，是 因为少突胶质细胞产生了髓鞘——一种富含胆固醇并包被轴突的膜。髓鞘的功能是分隔轴突，类似于电缆上包被的塑料。除此之外，髓鞘加速沿轴突的信息交流并使 交流更加可靠。当髓鞘包被受到攻击并降解时，冲动——由脑向身体其他部分传递的信息——可能“漏出”并且不能传递到目标位置。少突胶质细胞也可能参与其他 对神经元及其轴突非常重要的活动。

The researchers took B cells from the bloodof seven patients with relapsing-remitting MS and from four healthy patients.They grew the cells in a medium, and after removing the cells from the culturecollected material produced by the cells. After adding the material produced bythe B cells, including the cells that produce myelin, to the brain cells ofanimal models, the scientists found significantly more oligodendrocytes fromthe MS group died when compared to material produced by the B cells from thehealthy control group. The team also found differences in other brain cellsthat interact with oligodendrocytes in the brain.

研究者从7名复发缓解型MS患者和4名健康受试者的血中获取了B细胞。他们在培养基中培养这些细胞，并在把这些细胞从培养基中移出后收集了细胞所产生的物质。将这些由B细胞产生的物质——包括产生髓鞘的细胞——至动物模型的脑 细胞后，科学家发现与加入健康对照B细胞产生物质的模型相比，加入MS患者B细胞产生物质的模型中明显有更多的少突胶质细胞死亡。研究组还在脑内与少突胶 质细胞相互作用的其他脑细胞中发现了差异。

"We think this is a very significantfinding, particularly for the damage to the cerebral cortex seen in patientswith MS, because those areas seem to be damaged by material spreading into thebrain from the meninges, which are rich in B cells adjacent to the areas ofbrain damage," Lisak said.

“我们认为这是一项非常显著的发现，尤其是对可见的MS患者大脑皮质的损害来说，因为这些区域看起来是被由脑膜扩散至脑的物质所损害的，而邻近脑损害区域的脑膜富含B细胞。” Lisak说。

The team is now applying for grants fromseveral sources to conduct further studies to identify the toxic factor orfactors produced by B cells responsible for killing oligodendrocytes.Identification of the substance could lead to new therapeutic methods thatcould switch off the oligodendrocyte-killing capabilities of B cells, which, inturn, would help protect myelin from attacks.

研究小组正在从多个来源处申请进一步研究的许可，进一步的研究着力于确定B细胞产生的真正杀死少突胶质细胞的毒性因子。这类物质的确定将使关闭B细胞杀死少突胶质细胞能力成为新的治疗方法，这反过来也将帮助保护髓鞘免受攻击。