Razi Vaccine & Serum Research Institute Co-Publisher: Negah Scientific Publisher Archives of Razi Institute 0365-3439 71 2 2016 06 01 In silico analysis of Ta9 gene polymorphism in an Iranian Theileria annulata schizont-infected cell line S15 vaccine strain and native isolates بررسی in silico پلیمرفیسم ژن Ta9 در سویه S15 رده سلولی شیزونت تیلریا آنولاتا واکسن ایران و جدایه‌های بومی 71 80 106444 10.22034/ari.2016.106444 EN G. Habibi Department of Parasite Vaccine Research and Production, Razi Vaccine and Serum Research Institute, Karaj, Iran Journal Article 2015 04 01 <em>Bovine theileriosis</em> is a tick-borne disease caused by obligate intracellular parasites related to the genus <em>Theileria</em>. Cellular immune responses protect cattle against pathogens through the activation of immune cells. Nowadays, live, attenuated vaccine of <em>Theileria annulata </em>(<em>T. annulata</em>) is being produced in Iran and is recommended for active cattle immunization. Detection of the immunogenic  antigens and epitopes recognized by CD8+ T Lymphocytes is vital for the development of recombinant and subunit vaccines.<em> Herein, sequences of the genes encoding Ta9, which is an important antigen</em>recognized by bovine CD8+ T cells specific for <em>T. annulata, </em>in Iranian S15 vaccine strains, several Iranian isolates, as well as reference Ta9 DNA sequences registered in GeneBank were compared through polymerase chain reaction (PCR). The obtained data from DNA sequences were analyzed by using "Nucleotide", "Blast n", "BioEdit" and "IEDB" softwares. The results showed high level of variation in nucleotides and amino acids level. The observed polymorphism in Ta9 gene sequences of Iranian vaccine strains and some isolates from Iran demonstrated that this antigen contains polymorphic sequences and is active along with the specific major histocompatibility complex (MHC) of the host. Polymorphic sequences and specific epitopes of Ta9 gene for CD8+ T cell provides an explanation for incomplete protection observed after inoculation of heterologous parasites in vaccinated cattle. These results have important implications for the application of Ta9 antigen for developing novel subunit vaccines. <br />  https://archrazi.areeo.ac.ir/article_106444_37f454deb67a8d952a692291fd592daf.pdf