Schild G C, Oxford J S, Virelizier J L
Dev Biol Stand. 1975;28:253-72.
Immunity to influenza virus may be considered from the standpoints of viral and hostfactors. Amonst viral factors the phenomena of antigenic 'shift' and 'drift' of the surface antigens. Hemagglutinin HA and neuraminidase NA, are of utmost importance in enabling the virus to combat host immunity and to produce recurrent pandemics and epidemics of disease. 'Shift' involves major changes in the antigenic character of the HA and NA antigens, and serological studies reveal little or no crossreactions between antigens of different subtypes. However, immunological 'memory' may exist between the surface antigens of viruses of different subtypes, for example between the hemagglutinins of Asian (H2) and Hong Kong (H3) subtypes. Antigenic 'drift' occurs more frequently than 'shift' and involves subtle changes in the antigenic configuration of HA and NA within a subtype. It is clear that the hemagglutinin antigen contains a multiplicity of antigenic determinants, one or more of which remain stable (CR determinants) whilst others (strain-specific determinants) change completely during antigenic 'drift'. Amongst host factors humoral antibody to HA and NA appears to be a reasonable index of natural or vaccine induced immunity to infection. As far as the specificity of such antibodies is concerned, it is likely that future studies will place considerable emphasis on the distinction between antibody for the stable (CR) antigenic determinants and antibody to strain-specific determinants. It seems likely that antibody to strain-specific determinants is of more relevance to immunity than CR antibody. The studies of Virelizier et al. described elsewhere in this Symposium employing single-radial-diffusion tests give hope of simple methods for the investigation of such antibody specificity. There is no evidence that antibody to the internal, antigenically stable ribonucleoprotein is related to immunitywhilst the role of the other internal antigen, the membrane protein, in immunity is at present unknown. Numerous studies have been carried out to establish the importance of secretory antibody in the respiratory tract. Although secretory IgA specific for the influenza virus has been clearly demonstrated in the respiratory tract, the levels are low and its significance is not yet established. Whilst the role of cellular aspects of immunity to influenza in man remains to be established there is no doubt from the recent studies of Tyrrell and his colleagues that delayed hypersensitivity to influenza antigens can be demonstrated. In considering the host aspects of immunity it is important to attempt to distinguish factors which are merely an index of past exposure and those which are involved with the actual mechanism of immunity. It is likely that animal experimental models, in particular with inbred mice, will provide an important contribution in this field of investigation.
可以从病毒因素和宿主因素的角度来考虑对流感病毒的免疫。在病毒因素中，表面抗原血凝素（HA）和神经氨酸酶（NA）的抗原“转变”和“漂移”现象极为重要，它们使病毒能够对抗宿主免疫，并引发反复的大流行和疾病流行。“转变”涉及HA和NA抗原的抗原特性发生重大变化，血清学研究表明不同亚型的抗原之间几乎没有交叉反应。然而，不同亚型病毒的表面抗原之间可能存在免疫“记忆”，例如亚洲（H2）亚型和香港（H3）亚型的血凝素之间。抗原“漂移”比“转变”更频繁地发生，它涉及同一亚型内HA和NA抗原构型的细微变化。显然，血凝素抗原包含多种抗原决定簇，其中一个或多个保持稳定（CR决定簇），而其他的（菌株特异性决定簇）在抗原“漂移”过程中完全改变。在宿主因素中，针对HA和NA的体液抗体似乎是自然免疫或疫苗诱导免疫感染的合理指标。就此类抗体的特异性而言，未来的研究可能会相当重视区分针对稳定（CR）抗原决定簇的抗体和针对菌株特异性决定簇的抗体。似乎针对菌株特异性决定簇的抗体比CR抗体与免疫更相关。本次研讨会其他地方描述的Virelizier等人使用单向辐射扩散试验进行的研究，为研究此类抗体特异性的简单方法带来了希望。没有证据表明针对内部抗原稳定的核糖核蛋白的抗体与免疫有关，而另一种内部抗原膜蛋白在免疫中的作用目前尚不清楚。已经进行了大量研究来确定呼吸道中分泌性抗体的重要性。尽管呼吸道中针对流感病毒的分泌性IgA已得到明确证实，但其水平较低，其意义尚未确定。虽然人类对流感免疫的细胞方面的作用仍有待确定，但从Tyrrell及其同事最近的研究中无疑可以证明对流感抗原的迟发型超敏反应。在考虑免疫的宿主方面时，重要的是要试图区分仅仅是过去接触指标的因素和那些与实际免疫机制有关的因素。动物实验模型，特别是近交系小鼠，可能会在这个研究领域做出重要贡献。
