نگاهی به ایمونولوژی و واکسن‌های تولید شده بر علیه تیلریوز گاوی

حبیبی, غلامرضا; هاشمی فشارکی, رضا

doi:10.22092/vj.2014.100994

نگاهی به ایمونولوژی و واکسن‌های تولید شده بر علیه تیلریوز گاوی

شناسنامه علمی شماره

نویسندگان

¹ استادیار موسسه تحقیقات واکسن و سرم سازی رازی،کرج

² استاد موسسه تحقیقات واکسن و سرن سازی رازی،کرج

10.22092/vj.2014.100994

چکیده

تیلریوز گرمسیری بیماری انگلی ناشی از عفونت سلولهای میلوئیدی (متوسیت و ماکروفاژ ) و لمفوئیدی (لمفوسیت های B) به تک یاخته تیلریا آنولاتا بوده و در مرحله ای موجب آلودگی گلبول های قرمز خون نیز می شود. بیماری به وسیله کنه های جنس هیالوما منتقل شده و موجب عوارض گسترده ای از تب و کم خونی مختصر تا در گیری شدید اعضا لمفاوی بدن شده که می تواند در نژاد های حساس تلفاتینیز به همراه داشته باشد.با توجه به زندگی اجباری درون سلولی تک یاخته،سیستم ایمنی سلولی تنها بازوی موثر و محافظت کننده بدن در برابر تیلریا می باشدو ایمنی هومورال با تولید آنتی بادی های اختصاصی بر علیه اشکال اسپوروزوایت و مروزوایت های آزاد تنها قادر به کاهش قدرت عفونت زایی تیلریا می باشد.در مقابل،پاسخ ایمنی سلولی با فعالیت مجموعه ای از سلولهای T.NKC و ماکروفاژها و مشتقات آنها نظیر اینتر فرون گاما و TNF-a و بخصوص لمفوسیت های TCB8+ بخوبی در برابر شیزونت درون سلولی و سلول های آلوده به تیلریاپاسخ داده و موجب مرگ سلول های آلوده می شوند و با تولید خاطره ایمنی از بروز دوباره بیماری جلوگیری بعمل می آورند.البته نقش ایمنی طبیعی یا ذاتی همچون عوامل مکملو سلول های بیگانه خوار،به خصوص در مراحل اولیه عفونت از اهمیت خاصی برخوردار است.با توجه به حضور تیلریا و کنه ناقا بیماری در ایران و از طرفی وجود آلودگی در حیوانات اهلی و وحشی حامل تک یاخته که موجب بومی کردن بیماری شده اند تلاش هایی به منظور تولید واکسن در بسیاری از کشورها منجمله ایران صورت گرفته است.واکسن های نو ترکیب متنوعی بر علیه آنتی ژن های مربوط به مراحل مروزوایت و اسپوروزوایت بصورت آزمایشی تهیه شده است که در بررسی های صحرایی موفقیتهایی نسبی به همراه داشته اند.در حال حاضر واکسن زنده تخفیف حدت یافته تیلریا آنولاتا با فناوری کشت سلول های آلوده به شیزونت،قدرت محافظت کنندگیو پاسخ CTL قوی که دارد بر اساس تجربیات نزدیک به چهاردهه واکسیناسیون ملی در ایران و همچنین توصیه مراکز بین المللی نظیر OIEو FAO جهت ایمن سازی فعال گاوهای نژاد حساس و دو رگ بهترین گزینه می باشد.

20.1001.1.24235407.1393.27.2.11.6

عنوان مقاله [English]

A Glance at the Immunity and Vaccines against Tropical Theileriosis

نویسندگان [English]

GR Habibi ¹
R Hashemi-Fesharki ²

¹ Assistant Professor of Razi vaccine and serum research institute, Karaj

² Professor of Razi vaccine and serum research institute, Karaj

چکیده [English]

Tropical Theileriosis is caused by infection of bovine myeloid mononuclear cells (Monocytes and macrophages) and lymphoid cells (B lymphocytes) as well as red blood cells by the protozoan parasite Theileria annulata. The disease is transmitted by ticks of the genus Hyalomma. The clinical signs of theileriosis in stages appear from mild symptoms to serious, including fever and anemia to severe involvement of lymphoid organs that can cause death. The cellular immunity is a main part of effective and protective against Theileria infection as an intracellular protozoan, but the humoral immunity with specific antibody had a neutralizing effect directed against extracellular sporozoites and merozoites. But the adaptive cell-mediated immunity is driven by activation of T cells, macrophages and natural killer cells (NKC) and their derivatives like as IFN-gamma and TNF-alpha can respond to schizont infected cells, particularly CD8+ T cells kill these infected cells and remain as memory T cells for the next parasite challenge. However, the innate immune response such as the complement system and phagocytic cells is believed to play an important role in protecting against bovine theileriosis especially during primary stage of Theileria infection. Iran as a sub-tropical region and the Hyalomma spp. vector for transmission of the Theileria annulata make the Theileriosis as an endemic disease. The circulating Theileria parasites in carrier domestic and wild ruminants, and tick infestation make Theileriosis more difficult to control, therefore many efforts have been performed for producing the efficient bovine theileriosis vaccine. The recombinant candidate vaccines have been produced based on the merozoite and sporozoite stages of the protozoa and examined experimentally with partially success in the field. However, live attenuated Theileria annulata with cell culture methodology induced a strong, antigen-specific CTL activity for recognition by schizont antigen-specific cytotoxic T lymphocytes. Based on nearly four decades of our practical experiences on vaccination in Iran and the World Organisation for Animal Health (OIE) and the Food and Agriculture Organization of the United Nations (FAO) recommendations, the live attenuated vaccine is recommended as evidence-based strategies to control T. annulata infection by active immunization of susceptible exotic cattle and their cross-breds.

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