Banerjee Sudeshna, Mitra Tandrima, Purohit Gopal Krishna, Mohanty Sasmita, Mohanty Bimal Prasanna
ICAR- Central Inland Fisheries Research Institute, Fishery Resource and Environmental Management Division, Barrackpore, Kolkata, 700120, India.
KIIT University, School of Biotechnology, Bhubaneswar, 751024, Odisha, India.
Fish Shellfish Immunol. 2015 May;44(1):43-9. doi: 10.1016/j.fsi.2015.01.029. Epub 2015 Jan 31.
Immune system is fundamental for survival of an organism against invading pathogens and other harmful agents. Cytokines, the signaling proteins that are produced transiently after cell activation and exert pleiotropic effects on cells of the immune system, are important mediators of cell mediated immune response. When expressed in a dysregulated fashion cytokines can underlie either immunodeficient or immunopathologic states. Heat shock proteins (stress proteins, HSPs) are also key proteins, which play important role in immunomodulation, apoptosis and influence the immune responses. Arsenic is a major toxic environmental contaminant and a human carcinogen. Prolonged drinking of arsenic-contaminated water leads to chronic arsenic toxicity (arsenicosis). Arsenic is also immunotoxic and renders the host immunocompromised. Arsenic exposure has been reported to result in growth retardation, gross pathology including skin and eye lesions, ulcerations, cataract development etc. in different fish species. The present study was undertaken to investigate the effect of arsenic exposure on the expression of immune genes IFN-γ, IL-4, IL-10, IL-12, complement C3a and HSP genes HSP47, HSP60, HSP70, HSC71, HSP78, and HSP90 in Labeo rohita, an important aquacultured species, as such information is not available on this major carp. Cytokine and HSP gene expression analyses were carried out in kidney and liver tissues, respectively, in arsenic-exposed fishes by RT-PCR and HSPs were analyzed by immunoblotting. It was observed that arsenic has a generalized immune-suppressive effect leading to down regulation of both Th1 and Th2 cytokines; besides, it led to up regulation of the HSP genes indicating arsenic-induced cellular stress. Thus arsenic exposure makes L. rohita immunocompromised and could increase its susceptibility to pathogen attacks.
免疫系统对于生物体抵御入侵病原体和其他有害因子的生存至关重要。细胞因子是细胞激活后短暂产生的信号蛋白，对免疫系统细胞发挥多效性作用，是细胞介导免疫反应的重要介质。当细胞因子以失调的方式表达时，可导致免疫缺陷或免疫病理状态。热休克蛋白（应激蛋白，HSPs）也是关键蛋白，在免疫调节、细胞凋亡中起重要作用，并影响免疫反应。砷是一种主要的有毒环境污染物和人类致癌物。长期饮用受砷污染的水会导致慢性砷中毒（砷中毒症）。砷还具有免疫毒性，使宿主免疫功能受损。据报道，砷暴露会导致不同鱼类生长迟缓、出现包括皮肤和眼部病变、溃疡、白内障发展等在内的大体病理变化。本研究旨在调查砷暴露对重要养殖鱼类印度大鲤鱼（Labeo rohita）免疫基因IFN-γ、IL-4、IL-10、IL-12、补体C3a以及HSP基因HSP47、HSP60、HSP70、HSC71、HSP78和HSP90表达的影响，因为关于这种主要鲤鱼的此类信息尚不可得。通过RT-PCR分别在砷暴露鱼类的肾脏和肝脏组织中进行细胞因子和HSP基因表达分析，并通过免疫印迹分析HSPs。观察到砷具有普遍的免疫抑制作用，导致Th1和Th2细胞因子均下调；此外，它还导致HSP基因上调，表明砷诱导细胞应激。因此，砷暴露使印度大鲤鱼免疫功能受损，并可能增加其对病原体攻击的易感性。
