Mapping tissue immunity in the human urinary bladder across lifespan

膀胱是位于下腹部的中空球形器官。它是泌尿道的一部分，负责排出体内的废物和多余的水。尿液含有废物和多余的液体，由肾脏产生，并在排尿前被运送到膀胱储存。这意味着膀胱相对靠近外部环境，并且可能受到来自身体表面的细菌（微生物）的攻击，包括源自肠道的微生物。我们知道，包括膀胱在内的所有器官都含有一些有助于抵抗微生物的常驻防御（免疫）细胞。尽管如此，膀胱感染是常见的，在其一生中影响1/2的女性和1/20的男性。膀胱感染的易感性随着年龄的增长而增加，其他膀胱疾病也是如此，如炎症（可以引起疼痛或失禁等症状）和癌症。尽管免疫细胞在所有这些疾病中起着重要作用，但我们目前还不了解膀胱防御是如何建立的，这是如何随着年龄的增长而出错或变化的，以及男性和女性之间的差异。我们的研究项目旨在解决这一知识差距。我们的总体目标是绘制出人类膀胱中所有免疫细胞在整个生命周期中的分布图或图谱，包括男性和女性。我们将采取两种实验方法：第一种是取一块人类膀胱，并将其捣碎，这样我们就可以分析单个细胞，包括免疫细胞。不同的细胞具有不同的功能和识别标记，因为它们的遗传物质（称为基因）不同，以及它们的遗传密码如何被翻译成细胞的工作部分（称为蛋白质）的差异。每个细胞都含有数千种蛋白质，但这些蛋白质很难在单个细胞中进行大规模测量。然而，我们可以测量作为基因和蛋白质之间的中间体的分子-这被称为信使RNA或mRNA。在过去的10年里，技术已经发展到我们可以测量单个细胞中数千个mRNA分子，这就是我们计划对捣碎的膀胱样本所做的。我们已经获得了伦理许可，可以在整个生命周期内采集人类膀胱样本，包括胚胎（来自纽卡斯尔大学的人类发育生物学资源）和成人（来自剑桥的器官捐赠者，他们同意将自己的组织用于研究）。我们的第二种实验方法是取一块膀胱，保持其完整，以便维持空间中细胞的关系。然后，我们将膀胱切片，使它们足够薄，以便在显微镜下观察。我们将使用我们第一个实验中的mRNA信息来识别蛋白质标记物，这些标记物可以通过显微镜使用荧光标记的探针进行可视化，我们还可以在空间中绘制mRNA分子。这将使我们能够研究细胞相对于彼此的位置，并确定男性和女性之间细胞的位置是否不同，在整个生命周期中绘制膀胱细胞的完整图谱将提供一个重要的参考图谱，这将有助于研究人员在未来了解哪些细胞在不同的膀胱疾病中变得异常，以及如何可能在不同的膀胱疾病中发现异常细胞。防止与年龄有关的无益变化。

The urinary bladder is a hollow spherical organ situated in the lower abdomen. It forms part of the urinary tract, which is responsible for expelling waste and surplus water from the body. Urine, containing waste and excess fluid, is produced by the kidneys, and transported to the bladder where it is stored prior to voiding. This means that the bladder is in relatively close proximity to the external environment, and may be attacked by bugs (microbes) coming in from body surfaces, including microbes originating in the gut. We know that all organs, including the bladder, contain some resident defence (immune) cells that help to fight off microbes. Despite this, infection of the bladder is common, affecting 1 in 2 women in their lifetime and 1 in 20 men. Susceptibility to bladder infection increases with age, as do other bladder diseases, like inflammation (that can give symptoms such as pain or incontinence) and cancer. Despite the fact that immune cells play an important role in all of these conditions, we currently don't understand the details of how bladder defence is set-up, how this goes wrong or changes with age, and how this differs between men and women. Our research project aims to address this knowledge gap. Our overall aim is to produce a map or atlas of all the immune cells in the human bladder across lifespan, in men and women.We will take two experimental approaches: The first is to take a piece of human bladder, and to mash it up so that we can analyse individual cells, including immune cells. Different cells have different functions and identification marks because of differences in their genetic material (called genes), and differences in how their genetic code is translated into the working parts of cells, called proteins. Every cell contains thousands of proteins, but these are hard to measure at scale in a single cell. However, we can measure the molecule that acts as an intermediate between genes and proteins - this is called messenger RNA or mRNA. In the past 10 years, technology has advanced such that we can measure thousands of mRNA molecules in a single cell, this is what we plan to do with the mashed bladder samples. We already have ethical permissions in place to take human bladder samples across lifespan, including from embryos (from the Human Development Biology Resource at Newcastle University), and adults (from organ donors in Cambridge that have consented for their tissues to be used for research).Our second experimental approach is to take a piece of bladder and keep it intact so that the relationship of the cells in space is maintained. We will then make slices of the piece of bladder so that they are thin enough to be visualised under a microscope. We will use the mRNA information from our first experiment to identify protein markers that can be visualised by the microscope using probes that are fluorescently labelled and we can also map mRNA molecules in space. This will allow us to investigate the position of cells relative to each other and to determine whether the position of cells differs between men and women, and in the adult and developing bladder.Making a complete map of cells in the bladder across lifespan will provide a critical reference atlas that will help researchers in the future to understand which cells become abnormal in different bladder diseases and how it might be possible to prevent unhelpful age-related changes.