Morphological and chemical changes in the hemolymph of the wax moth Galleria mellonella infected by the entomopathogenic fungus Conidiobolus coronatus

Data are provided on changes in the hemolymph of Galleria mellonella Linnaeus 1758 (Lepidoptera: Pyralidae) larvae infected with the soil fungus Conidiobolus coronatus (Constantin) Batko 1964 (Entomophthorales). Hemolymph enables communication between organs in insects and ensures necessary coordination and homeostasis. Its composition can provide important information about the physiological state of an insect and can have diagnostic significance, which might be particularly important in the case of harmful insects subjected to biological control. Galleria mellonella is a global pest to honey bee colonies. The hemolymph of its larvae was examined after infection with Conidiobolus coronatus. It was found that after one hour of contact with the fungus, the volume of the hemolymph increased while its total protein content decreased. In larvae with a high pathogen load, just before death, hemolymph volume decreased to nearly initial levels, while total protein content and synthesis (incorporation of 35S-labeled methionine) increased. The hemolymph polypeptide profile (SDS-PAGE followed by autoradiography) of infected insects was significantly different from that of healthy larvae. Hemocytes of infected larvae did not surround the fungal hyphae, although they encapsulated small foreign bodies (phase contrast microscopy). Infection had a negative effect on hemocytes, causing oenocyte and spherulocyte deformation, granulocyte degranulation, plasmatocyte vacuolization, and hemocyte disintegration. GC-MS analysis revealed the presence of 21 compounds in the hemolymph of control insects. C. coronatus infection caused the appearance of 5 fatty acids absent in healthy larvae (heptanoic, decanoic, adipic, suberic, tridecanoic), the disappearance of 4 compounds (monopalmitoylglycerol, monooleoylglycerol, monostearin, and cholesterol), and changes in the concentrations of 8 compounds. It remains an open question whether substances appearing in the hemolymph of infected insects are a product of the fungus or if they are released from the insect tissues damaged by the growing hyphae.

本数据集提供了被土壤真菌冠状耳霉（Conidiobolus coronatus (Constantin) Batko 1964，虫霉目）侵染的大蜡螟（Galleria mellonella Linnaeus 1758，鳞翅目：螟蛾科）幼虫血淋巴（hemolymph）的变化数据。血淋巴是昆虫体内器官间通讯的媒介，可保障机体必要的协调运作与内稳态。其组成成分能够反映昆虫的生理状态，具备诊断参考价值，这对于开展生物防治的有害昆虫而言尤为关键。大蜡螟是全球范围内危害蜂群的重要害虫。本研究对被冠状耳霉侵染的大蜡螟幼虫血淋巴进行了检测分析。研究结果显示，与真菌接触1小时后，幼虫血淋巴体积出现上升，而总蛋白含量则有所下降。当幼虫体内病原菌载量较高、临近死亡时，其血淋巴体积回落至接近初始水平，而总蛋白含量与合成速率（35S标记甲硫氨酸掺入量）则出现上升。受侵染昆虫的血淋巴多肽谱（采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）结合放射自显影技术检测）与健康幼虫存在显著差异。受侵染幼虫的血细胞（hemocyte）虽可通过包裹作用清除小型异物（相差显微镜观测结果），却无法对真菌菌丝形成包围。侵染过程对幼虫血细胞产生了负面影响，具体表现为成脂细胞（oenocyte）与球细胞（spherulocyte）变形、颗粒细胞（granulocyte）脱颗粒、浆血细胞（plasmatocyte）空泡化以及血细胞解体。气相色谱-质谱联用（GC-MS）分析结果显示，对照组幼虫的血淋巴中可检测到21种化合物。冠状耳霉侵染导致健康幼虫血淋巴中原本不存在的5种脂肪酸出现（分别为庚酸、癸酸、己二酸、辛二酸、十三烷酸），同时使4种化合物消失（单棕榈酸甘油酯、单油酸甘油酯、单硬脂酸甘油酯与胆固醇），并改变了另外8种化合物的浓度。目前仍存在一个尚未解决的问题：受侵染昆虫血淋巴中出现的物质究竟是真菌的代谢产物，还是由生长菌丝破坏昆虫组织后释放的成分。