Tumor necrosis factor superfamily (TNFSF) molecules are important inflammatory cytokines, which are involved in diverse immunological functions such as B-cell regulation and B-cell-mediated immune responses. Existence of numerous tumor necrosis factor (TNF) members in the evolutionary lower vertebrate species has been reported; however, their immune functions are yet to be explored. Therefore, the existence of TNFSF members such as B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) were identified in the freshwater carp, Catla catla. The BAFF and APRIL of C. catla (CcBAFF) and (CcAPRIL) were confirmed with the help of bioinformatic analysis. The CcBAFF showed higher structural identity with the BAFF of Xenopus laevis (amphibian) and BAFF-human. Further, the phylogenetic analysis ensured the conserved sequence similar to that of other teleosts. CcBAFF protein sequence had a predicted transmembrane domain and a typical TNF homology domain. CcBAFF and CcAPRIL were found to be constitutively expressed in all the immunological tissues. Spleen and gill had shown an elevated expression compared with other tissues in all the infected/stimulated (bacterial, viral antigen, and parasitic) fish. Stimulation by ligands (Poly I:C, LPS, PGN, and FLA) in C. catla had shown an elevation in the expression of CcBAFF and CcAPRIL in spleen and gill at different time intervals. The expression of recombinant CcBAFF has been confirmed with the immunoblotting. Thus, this is the first report that indicates the presence of BAFF and APRIL in Catla catla and its potential role in immunity.

肿瘤坏死因子超家族（TNFSF）分子是重要的炎症细胞因子，参与多种免疫功能，例如B细胞调节和B细胞介导的免疫反应。据报道，在进化的低等脊椎动物物种中存在许多肿瘤坏死因子（TNF）成员。然而，它们的免疫功能尚待探索。因此，在淡水鲤鱼Catla catla中发现了TNFSF成员的存在，例如B细胞活化因子（BAFF）和增殖诱导配体（APRIL）。在生物信息学分析的帮助下，确定了C. catla的BAFF和APRIL （CcBAFF）和（CcAPRIL）。该抄送BAFF与非洲爪蟾（两栖动物）的BAFF和人的BAFF显示出更高的结构同一性。此外，系统发育分析确保了与其他硬骨鱼相似的保守序列。Cc BAFF蛋白序列具有预测的跨膜结构域和典型的TNF同源结构域。发现Cc BAFF和Cc APRIL在所有免疫组织中组成性表达。与所有受感染/刺激的（细菌，病毒抗原和寄生虫）鱼相比，脾脏和g的表达均高于其他组织。C. catla中配体（Poly I：C，LPS，PGN和FLA）的刺激显示CcBAFF和CcAPRIL的表达升高在脾脏和腮中的时间间隔不同。免疫印迹证实了重组Cc BAFF的表达。因此，这是第一个报告，表明Catla catla中BAFF和APRIL的存在及其在免疫中的潜在作用。