Quantifying and modeling the transmission dynamics of bivalve transmissible neoplasia

癌症通常不被认为是一种传染病。然而，最近在野外发现了几种传染性癌症，其中癌细胞本身作为传染媒介在动物之间传播，在陆地和海洋环境中造成重大死亡。海洋双壳类动物似乎特别容易受到影响。自不到十年前该小组成员首次将双壳类动物识别为传染性癌症以来，至少在全球八种双壳类动物中发现了九种致命的传染性癌症。众所周知，整个癌细胞从一只动物转移到另一只动物，但尚不清楚这种传染病是如何在个体水平上、在单个种群内或在环境中的种群之间传播的。这个跨学科的团队正在将疾病流行的敏感实地调查、实验室接种、体外实验与定量建模结合起来，以了解这类独特的传染病是如何在自然界传播的。该小组将继续通过科学出版物和与商业水产养殖和当地美洲原住民社区（包括多个海岸萨利希部落的研究伙伴）的会议，传播该项目的成果。了解疾病传播原理可能有助于制定控制这种疾病的战略，这将直接帮助这些社区。该团队成员还在太平洋西北研究所、西华盛顿大学和毕格罗海洋科学实验室的夏季研究经历中培训本科生。为了了解双壳类传染性癌症传播的基本原理，研究小组研究了地理上分离物种的两个独立谱系：北美大西洋沿岸的软壳蛤（Mya arenaria），这是第一个发现的双壳类传染性癌症；篮蛤（Clinocardium nuttallii），一种北美太平洋沿岸的物种，该团队最近刚刚在其中发现了双壳类传染性癌症。该团队正在开发两个定量模型，一个用于疾病在人群中随着时间的推移而传播，另一个用于模拟不同人群之间癌症谱系的传播。他们正在用来自多个地点的野生种群的常规疾病流行数据来测试这些模型。通过提供关键参数值和测试环境变量（如温度）或遗传变量（如癌症和宿主的相关性）是否影响疾病进展的易感性和时间，疾病进展和传播的实验室工作支持这些模型的开发和完善。本项目旨在定量了解软壳蛤和篮贝的疾病动态。最终，它将为这类最近发现的传染病的传播提供一般原理。该项目由环境生物学部和海洋科学学部资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Cancer is not normally thought of as an infectious disease. However, several transmissible cancers have recently been found in the wild, in which the cancer cells themselves jump from animal to animal as an infectious agent, causing significant mortality on land and in the marine environment. Marine bivalves appear to be particularly susceptible. At least nine lineages of lethal transmissible cancer have been identified in eight bivalve species worldwide since they were first recognized as an infectious cancer by members of this team less than a decade ago. It is known that whole cancer cells transfer from one animal to another, but it is unclear how this infectious disease spreads at the individual level, within a single population, or between populations in the environment. The interdisciplinary team is combining sensitive field surveys of disease prevalence, laboratory inoculation, and in vitro experiments together with quantitative modeling to understand how this unique class of infectious disease spreads in nature. The team will continue to communicate the results of this project through scientific publications and meetings with commercial aquaculture and local Native American communities, including research partners in multiple Coast Salish Tribes. Understanding the disease transmission principles may help develop strategies to control this disease, which would directly help these communities. The team members are also training undergraduate students during summer research experiences at Pacific Northwest Research Institute, Western Washington University, and Bigelow Laboratory for Ocean Sciences. To understand the basic principles of the spread of bivalve transmissible cancer, the team studies two separate lineages in geographically separated species: soft-shell clams (Mya arenaria) on the Atlantic Coast of North America, the first bivalve transmissible cancer identified; and basket cockles (Clinocardium nuttallii), a species on the Pacific Coast of North America, in which the team has just recently identified bivalve transmissible cancer. The team is developing two quantitative models, one for the spread of disease within a population over time, and a second to model the spread of cancer lineages between different populations. They are testing these models with regular disease prevalence data from wild populations from multiple sites. Laboratory work on disease progression and transmission supports development and refinement of these models by providing critical parameter values and testing whether environmental variables (such as temperature) or genetic variables (such as the relatedness of cancer and host) affect the susceptibility and timing of disease progression. This project aims to develop a quantitative understanding of disease dynamics in soft-shell clams and basket cockles. Ultimately, it will provide general principles that underlie the spread of this recently discovered class of infectious disease.This project was funded by the Division of Environmental Biology and the Division of Ocean Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.