CANCER - A BIOLOGICAL APPROACH .3. VIRUSES ASSOCIATED WITH NEOPLASTIC CONDITIONS
CANCER - A BIOLOGICAL APPROACH .3. VIRUSES ASSOCIATED WITH NEOPLASTIC CONDITIONS
复制标题
DOI：
10.1136/bmj.1.5023.841
复制
发表时间：
1957-01-01
影响因子：
105.7
通讯作者：
BURNET, M
中科院分区：
文献类型：
--
作者：
BURNET, M
仍然有一个活跃的观点，认为癌症是一种寄生虫病，由于细胞被外来病毒感染。这种态度有很大的吸引力，它提出了直接的方法来预防癌症的免疫方法，并提出了更多的希望，最终有效的化疗。正如许多作者所指出的，认为某些肿瘤过程是由于病毒感染引起的说法，与承认体细胞突变的压倒一切的重要性并不矛盾。任何声称所有癌症都具有传染性的说法，在目前的知识水平上都是不合理的，坦率地说是荒谬的。病毒的定义从来都不是一件容易的事，而细菌中前病毒的存在，以及它与宿主遗传机制密切相关的令人信服的证据，使定义病毒变得更加困难。任何定义都必须涵盖这样一个事实，即存在两个非常不同的系统，通过适当的操作，可以从其中每一个系统中产生典型病毒感染的连续序列。它们分别是感染性颗粒和被感染的宿主细胞。病毒，通常被理解为一群感染性病毒颗粒的形式，可以被定义为比细菌小的自我复制因子或生物体，并且只能在活的易感宿主细胞内增殖。当我们必须讨论可证明的或假设的自我复制亚细胞实体时，可能需要添加某些限定条件。病毒颗粒必须显示携带与宿主细胞不同的蛋白质和核酸的特定模式，并且不是从宿主物种或与之相关的任何物种遗传而来的。在感染的某一阶段，宿主细胞可能不含病毒，这可以通过经典的方法来证明，即破碎细胞并将产物分散到其他易感细胞中。还有其他证据表明，在这个阶段，细胞中不含已形成的病毒颗粒。在某些情况下，这一阶段可能会延长。它的存在可以通过提供感染性病毒颗粒将发展并通过标准方法鉴定的情况或通过证明细胞中或从细胞中释放的特异性病毒抗原来识别。
There is still an active body of opinion that would regard cancer as a parasitic disease due to infection of cells by extrinsic viruses. Such an attitude has the great attrac-tion thatit suggests straightforward approaches to the prevention of cancer by immunological methods and holds out more hope of an eventual effective chemotherapy. As various writers have pointed out, the claim that some neoplastic processes are due to virus infection is not inconsistent with a recognition of the overriding importance of somatic mutation. Any claim that all cancers are of infective character is unjustified and frankly absurd in the present state of knowledge. It has never been easy to define a virus, and the recog-nition of provirus in bacteria, with the convincing evidence that it is intimately built into the host's genetic mechanism, has now made it even more difficult. Any definition must cover the fact that there are two very different systems from each of which by appropriate manipulations a continuing sequence of typical virus infections may be produced. These are respectively the infective particle and the infected host cell. A virus, in the conventionally understood form of a population of infective virus particles, can be defined as a self-replicating agent or organism smaller than bacteria and capable ofmultiplication only within living sus-ceptible host cells. It may be desirable to add certain qualifications whenwe have to discuss demonstrable or hypothetical self-replicating subcellular entities. A virus particle must beshown to carry specific patterns in protein and nucleic acid which are different from those of the host cell and which are not derived genetically from the host species or any species related to it. At a certain stage ofinfection, host cells may contain no virus demonstrable by the classic method of breaking up the cell and inoculating the product into other susceptible cells. There is other evidence that at this stage the cells do not contain formed virusparticles. Under certain circumstances this phase may be pro-longed. Its existence can be recognized either by providing a situation where infective virus particles will develop and be identified by standard methods or by demonstrating specific virus antigen in or liberated from the cells.