Toll-like receptors (TLRs) in innate immune system act as primary sensors in detecting the microbial components and activate their signaling cascades to induce NF-κB (nuclear factor NF-κB) towards the augmentation of immunoglobulin (Ig) synthesis. To gain insights into the efficacy of NF-κB pathway in immunoglobulin D (IgD) synthesis in the Indian Major Carp Catla catla, cloning and sequencing of TLR-signaling downstream molecules [TRAF3 (TNF receptor-associated factor 3), NEMO (nuclear factor-kappa B essential modulator), NF-κB and BAFF (B cell activating factor)] were performed by infecting the fish with pathogens. mRNA expression analysis of the downstream molecules and IgD showed significant up-regulation of these genes in kidney (P ≤ 0.001) as compared to spleen (P ≤ 0.05). To ascertain the role of NF-κB pathway in IgD synthesis, the primary cell culture of kidney and spleen in monolayer cell suspension was treated with NF-κB inhibitor (BAY 11-7082) and down-regulation of BAFF, NEMO, NF-κB, and IgD gene was observed. These results highlight the importance of NF-κB signaling pathway in augmenting the IgD gene expression in the freshwater carp, Catla catla.

先天免疫系统中的 Toll 样受体 (TLR) 作为检测微生物成分的主要传感器，并激活它们的信号级联反应以诱导 NF-κB（核因子 NF-κB）增加免疫球蛋白（Ig）的合成。为了深入了解 NF-κB 通路在印度主要鲤鱼中免疫球蛋白 D (IgD) 合成中的功效，克隆和测序 TLR 信号下游分子 [TRAF3（TNF 受体相关因子 3）、NEMO（核因子） -kappa B 必需调节剂）、NF-κB 和 BAFF（B 细胞激活因子）] 是通过用病原体感染鱼来进行的。下游分子和 IgD 的 mRNA 表达分析显示 ，与脾脏相比，肾脏中这些基因的显着上调（P ≤ 0.001）（P ≤ 0.05)。为了确定 NF-κB 通路在 IgD 合成中的作用，用 NF-κB 抑制剂（BAY 11-7082）处理单层细胞悬液中肾和脾的原代细胞培养物，并下调BAFF、NEMO、NF-κB , 并观察到IgD基因。这些结果突出了 NF-κB 信号通路在增加淡水鲤鱼Catla catla 中IgD基因表达方面的重要性。