Transcriptome analysis reveals immune regulation in the spleen of koi carp (Cyprinus carpio Koi) during Aeromonas hydrophila infection

Elevated Levels of Interleukin-18 are Associated with Lymph Node Metastasis in Papillary Thyroid Carcinoma

Interleukin-18 (IL-18) is a proinflammatory cytokine that primarily stimulates the Th1 immune response. IL-18 exhibits anticancer activity and has been evaluated in clinical trials as a potential cancer treatment. However, evidence suggests that it may also facilitate the development and progression of some cancers. So far, the impact of IL-18 on papillary thyroid cancer (PTC) has not been investigated. In this study, we found that the expression of IL-18 was significantly increased in PTC compared to normal thyroid tissue. Elevated IL-18 expression was closely associated with lymphovascular invasion and lymph node metastases. Furthermore, compared to PTC patients with no nodal metastasis, serum IL-18 levels were slightly increased in patients with 1-4 nodal metastases and significantly elevated in patients with 5 or more nodal metastases. The pro-metastatic effect of IL-18 may be attributed to the simultaneous increase in the expression of S100A10, a known factor that is linked to nodal metastasis in PTC. In addition, the activation of several pathways, such as the intestinal immune network for lgA production and Staphylococcus aureus infection, may be involved in the metastasis process. Taken together, IL-18 may trigger pro-metastatic activity in PTC. Therefore, suppressing the function of IL-18 rather than enhancing it appears to be a reasonable strategy for treating aggressive PTC.

Transcriptome analysis of host anti-Aeromonas hydrophila infection revealed the pathogenicity of A. hydrophila to American eels (Anguilla rostrata)

Aeromonas hydrophila is a commonly pathogenic bacterium in cultivated eels, but its pathogenicity to American eel (Anguilla rostrata) and the molecular mechanism of host anti-A. hydrophila infection remains uncertain. In this study, LD50 of A. hydrophila to American eels was determined and bacterial load in the liver and kidney of eels was assessed post 2.56 doses of LD50 of A. hydrophila infection. The results showed that the LD50 of A. hydrophila to American eels was determined to be 3.9 × 105 cfu/g body weight (7.8 × 106 cfu/fish), and the bacterial load peaked at 36 h post the infection (hpi) in the liver. Then, the histopathology was highlighted by congestion in splenic blood vessels, atrophied glomeruli, and necrotic hepatocytes. Additionally, the results of qRT-PCR revealed that 18 host immune-related genes showed significantly up or downregulated post-infection compare to that of pre-infection. Finally, results of the RNA-seq revealed 10 hub DEGs and 7 encoded proteins play essential role to the anti-A. hydrophila infection in American eels. Pathogenicity of A. hydrophila to American eels and RNA-seq of host anti-A. hydrophila infection were firstly reported in this study, shedding new light on our understanding of the A. hydrophila pathogenesis and the host immune response to the A. hydrophila infection strategies in gene transcript.

Transcriptome Analysis of Host Anti-Vibrio harveyi Infection Revealed the Pathogenicity of V. harveyi to American Eel (Anguilla rostrata)

Vibrio harveyi, a recently discovered pathogenic bacterium isolated from American eels (Anguilla rostrata), poses uncertainties regarding its pathogenesis in American eel and the molecular mechanisms underlying host defense against V. harveyi infection. This study aimed to determine the LD50 of V. harveyi in American eel and assess the bacterial load in the liver, spleen, and kidney post-infection with the LD50 dose. The results showed that the LD50 of V. harveyi via intraperitoneal injection in American eels over a 14d period was determined to be 1.24 × 103 cfu/g body weight (6.2 × 104 cfu/fish). The peak bacterial load occurred at 36 h post-infection (hpi) in all three organs examined. Histopathology analysis revealed hepatic vein congestion and thrombi, tubular vacuolar degeneration, and splenic bleeding. Moreover, quantitative reverse transcription polymerase chain reaction (qRT-PCR) results indicated significant up or downregulation of 18 host immune- or anti-infection-related genes post 12 to 60 hpi following the infection. Additionally, RNA sequencing (RNA-seq) unveiled 7 hub differentially expressed genes (DEGs) and 11 encoded proteins play crucial roles in the anti-V. harveyi response in American eels. This study firstly represents the comprehensive report on the pathogenicity of V. harveyi to American eels and RNA-seq of host's response to V. harveyi infection. These findings provide valuable insights into V. harveyi pathogenesis and the strategies employed by the host's immune system at the transcriptomic level to combat V. harveyi infection.