Plant virus infection as a determinant of pollen allergenicity

花粉引起的鼻炎和结膜炎是一个主要的健康问题，目前英国四分之一的人口受到影响。植物的病毒感染是常见的，并有可能引起花粉粒组成的深刻变化。为了调查的概念，即病毒感染的草可以提高花粉刺激过敏反应的能力，提出了两个机构之间的合作与互补的专业知识：生态和水文中心（CEH）在牛津大学和感染，炎症和修复司的南安普顿大学。我们将集中在花粉从草物种牵连作为过敏性鼻结膜炎在英国的主要触发器。CEH的工作人员将为南安普顿的研究小组提供来自玻璃房种植的花黄草（甜春草）或鸭茅（鸭茅）的花粉，这些植物分别被特定的病毒（花黄草潜伏漂白大麦病毒、鸭茅条纹马铃薯Y病毒或鸭茅斑驳sobemovirus）侵入。大麦病毒可以通过花粉传播，而马铃薯Y病毒表达丰富的蛋白酶。这三种病毒都产生丰富的衣壳蛋白，它们的感染应该触发宿主表达广泛的防御蛋白。所有这些变化都可能发生在花器官中，因此来自受感染植物的花粉可能被其他过敏原污染。将在南安普顿使用适当的体外和体内模型研究病毒诱导的致敏效力改变的可能性。将仔细比较无病毒和病毒感染植物的花粉标准化提取物的蛋白质组分，并研究不同花粉提取物组分的IgE结合模式。将检查体外刺激肥大细胞和嗜碱性粒细胞活化的潜力，并探索蛋白酶或其他花粉成分改变上皮单层的能力。我们将设法引起草花粉过敏受试者的皮肤和上呼吸道的过敏反应，并比较无病毒和病毒感染草的花粉引起的反应。这项研究应提供的信息，在何种程度上植物病毒可能会改变花粉的潜力，诱导致敏或引起过敏反应。这将首次评估这些病毒作为花粉过敏的环境决定因素，并可能为减少社区疾病负担的新方法开辟道路。

Pollen-induced rhinitis and conjunctivitis represents a major health problem, with up to one in four of the UK population now affected. Virus infection of plants is common and has the potential to induce profound changes in the composition of pollen grains. In order to investigate the concept that virus-infection in grasses can enhance the ability of pollen to stimulate allergic reactions, a collaboration is proposed between two institutions with complementary expertise: the Centre for Ecology and Hydrology (CEH) in Oxford and the Infection, Inflammation and Repair Division of the University of Southampton. We will focus on pollens from grass species implicated as major triggers of allergic rhinoconjunctivitis in the UK. Staff of CEH will supply the Southampton team with pollen from glasshouse-grown Anthoxanthum odoratum (sweet vernal grass) or Dactylis glomerata (cocksfoot) separately invaded by specific viruses (Anthoxanthum latent blanching hordeivirus, Cocksfoot streak potyvirus or Cocksfoot mottle sobemovirus). The hordeivirus can be pollen-borne, while the potyvirus expresses abundant proteases. All of the three viruses produce abundant capsid proteins and their infections should trigger host expression of a wide range of defensive proteins. All these alterations can occur in flower organs so pollens from infected plants could become contaminated with additional allergens. The potential for virus-induced alterations in allergenic potency will be investigated in Southampton using appropriate in vitro and in vivo models. The protein components of standardised extracts of pollens from virus free and virus infected plants will be carefully compared, and patterns of IgE binding by components of the different pollen extracts investigated. The potential to stimulate mast cell and basophil activation in vitro will be examined, and the ability of proteases or other pollen constituents to alter epithelial monolayers explored. We shall seek to provoke allergic reactions in the skin and upper airways of grass pollen allergic subjects, and compare responses elicited with pollen from virus free and virus infected grasses. This study should provide information on the extent to which plant viruses may alter the potential of pollens to induce sensitisation or to elicit allergic reactions. This will allow for the first time an assessment of these viruses as environmental determinants of pollen allergy, and could open the way for new approaches to reduce the burden of disease in the community.