寄生蜂多分DNA病毒对寄主昆虫的免疫抑制作用

Supression of insects immunity by polydnavirus

多分 ＤＮＡ病毒（ＰＤＶ）是在膜翅目姬蜂科和茧蜂科寄生蜂体内的一类很独特的病毒。寄生蜂产 卵时，ＰＤＶ随同卵和萼液一起被注射入寄主体内，能干扰寄主的细胞免疫和体液免疫。该病毒直接侵染 或间接作用于血细胞，主要是浆细胞和颗粒细胞，导致血细胞变圆或凋亡。ＰＤＶ也能抑制血淋巴酚氧化 酶活性，诱导抗菌因子的大量合成。最近有关研究主要集中在病毒基因的表达和伴随寄主血细胞功能失常 的分子事件上。一些寄生蜂的ＰＤＶ与其他因子，如卵巢蛋白、畸形细胞或蜂毒等协同发挥作用。

Polydnavirus (PDV) has unique mutualistic associations with some ichneumonid and braconid wasps and disrupts host physiological systems, especially host immunity. During the oviposition process, a complex mixture of eggs, PDV and calyx fluid is injected into the host larva. PDV suppresses the insect cellular and humoral immune system, infecting directly or interacting indirectly with plasmatocytes and granular cells and leading to the cell's rounding up, and even apoptosis. PDV also inhibits Phenoloxidase activity, and induces plenty of antibacterial response peptides. Current researches focus on examining viral gene expression accompanying host im- munity dysfunction. In some parasitic wasps, PDV frequently has a synergistic effect with other factors, such as ovarian protein, teratocyte and venom.