急性肝胰腺壞死病 (Acute hepatopancreatic necrosis disease，AHPND) 為近年來重創全球蝦類養殖的細菌性疾病。致病性副溶血弧菌首先大量定殖於蝦胃，並藉由分泌具穿孔活性的Pir毒素破壞蝦隻胃部上皮細胞，最終轉移至肝胰腺，引起肝胰小管上皮細胞脫落及血球浸潤等病徵。然而，參與在致病菌轉移過程中的宿主分子機制仍需被進一步探討，經本實驗室之轉錄體學分析結果顯示，AHPND感染24小時後，DD9A基因於AHPND抗病蝦蝦胃中具有較高的表現程度，而此基因的表現主要與上皮組織外側之表皮結構的組成有關。本研究得到另一與DD9A核苷酸序列相似度高達94%的DD9B基因，並以分子實驗證明該兩基因的表現程度皆因AHPND或WSSV感染而顯著提升。接著，利用dsRNA所介導之基因靜默化抑制DD9A/B的基因表現後對蝦隻進行AHPND致病菌的浸泡感染，結果顯示，可於感染早期在肝胰腺中偵測到大量的致病性副溶血弧菌，且蝦隻外骨骼軟硬度明顯下降，而DD9A/B基因表現程度的降低，卻抑制了WSSV的基因表現量及基因體複製數。由以上結果推論，DD9A/B雖共同參與在AHPND與WSSV的致病過程中，但發揮的功能應有所不同，除了一方面延緩AHPND致病菌從蝦胃到肝胰腺的移動，另一方面則可促進WSSV的基因表現及其基因體複製。

Acute hepatopancreatic necrosis disease (AHPND) is a devastating bacterial disease caused by V. parahaemolyticus that can produce virulent toxin, Pirvp. Typically, AHPND-causing bacteria initially colonize the shrimp stomach and subsequently reach the hepatopancreas. To achieve this migration, they need to pass through physical structures between the two organs. However, underlying mechanisms remain unclear. Previous transcriptomic data found that a contig (PVHP92460.1) related to cuticular proteins LvDD9A and LvDD9B had a differentially higher expression level in AHPND-resistant shrimp. Since cuticle is consistently a structural barrier protecting hosts from pathogen invasion, we hypothesized that LvDD9A/B is involved in AHPND pathogenesis. In the present study, LvDD9A/B expression was significantly induced after AHPND challenge or WSSV injection. Following dsRNA-mediated gene silencing, there was the very early migration of AHPND-causing 5HP within 3 hours of AHPND infection in shrimp with downregulated LvDD9A/B expression. In addition, decreased mRNA levels of LvDD9A/B may reduce the hardness of the shrimp exoskeleton. Conversely, LvDD9A/B silencing significantly decreased WSSV genomic copies and gene expression. Taken together, we inferred that LvDD9A/B may have a role in slowing migration of AHPND-causing bacteria. However, these cuticular proteins facilitate viral genome replication and gene expression in WSSV infection.

張哲輊，利用轉錄體學探討蝦感染急性肝胰腺壞死病之宿主反應，國立成功大學生物科技研究所碩士論文，2016。

葉民德，探討蝦類Toll及IMD路徑在急性肝胰腺壞死症致病過程中所扮演的角色，國立成功大學生物科技研究所碩士論文，2015。

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