en Biotechnology Biotechnology پژوهشي Orginal research papers <span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">Sturgeon species are commercially important species in finfish aquaculture industry. Till now, a small number of studies have been reported on the immune responses in sturgeon species against infectious diseases. Monoclonal and polyclonal antibodies in fish immunoglobulins (Igs) are essential to evaluate the humoral immune response. This study aimed to produce, characterize, and evaluate the polyclonal antisera against stellate sturgeon Igs</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">.</span></span></span> <span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">For the production of polyclonal antibodies against fish Igs, stellate sturgeon serum Igs was isolated using the ammonium sulfate precipitation method. The </span></span></span><span lang="EN" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">purified Igs with </span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">the</span></span></span><span lang="EN" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> Freund adjuvant was injected</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> subcutaneously in</span></span></span><span lang="EN" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> to sheep (</span></span></span><i><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">Ovis aries</span></span></span></i><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">)</span></span></span><span lang="EN" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">.</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> Then, anti- stellate sturgeon Ig antibody</span></span></span> <span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">titer and specificity were determined using ELISA and </span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">Western blot</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> techniques. Stellate sturgeon Ig antibodies were detected in the immunized animals and were significantly higher in the immunized group compared to the non-immunized group. The polyclonal antisera </span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">showed a high specificity to</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> the immunoglobulin heavy </span></span></span><span dir="RTL" lang="AR-SA" style="font-size:11.0pt"><span arial="" style="font-family:"><span style="color:black">)</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">H</span></span></span><span dir="RTL" lang="AR-SA" style="font-size:11.0pt"><span arial="" style="font-family:"><span style="color:black">(</span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"> chain of stellate sturgeon and moderately cross-reacted with the immunoglobulin H chain in Siberian (<i>Acipenser baerii</i>) and ship (<i>A. nudiventris</i>) sturgeons but </span></span></span><span lang="EN-GB" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black"><span style="letter-spacing:.05pt">did not </span></span></span></span><span lang="TR" style="font-size:11.0pt"><span calibri="" style="font-family:"><span style="color:black">show reactivity with rainbow trout (<i>Oncorhynchus mykiss</i>) serum Igs<i>.</i> It was indicated that the produced polyclonal antisera should be further investigated to be used for immune-diagnostic purposes in sturgeon species upon exposure to various infectious diseases.</span></span></span> Acipenser stellatus, Immunoglobulin, Polyclonal antibody, Sturgeon 427 435 http://jifro.ir/browse.php?a_code=A-10-4570-1&slc_lang=en&sid=1 Azadeh Yektaseresht azadeh_neisi@shirazu.ac.ir 100319475328460051352 100319475328460051352 Yes Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran. Zahra Hemati zahra.hemati@gmail.com 100319475328460051353 100319475328460051353 No Department of Pathobiology, Faculty of Veterinary Medicine, University of Shahrekord, Shahrekord, Iran Amin Gholamhosseini amin.gholamhosseini@gmai.com 100319475328460051354 100319475328460051354 No Department of Clinical Sciences, Department, Veterinary School, Shiraz University Shiraz, Iran Amir Arsalan Khorsand amirarsalan.khorsand@gmai.com 100319475328460051355 100319475328460051355 No Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.