کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2462456 1555075 2010 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Ovine immune parameters following immunisation against Mycobacterium avium ssp. paratuberculosis using a lipid-based live-cell vaccine
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Ovine immune parameters following immunisation against Mycobacterium avium ssp. paratuberculosis using a lipid-based live-cell vaccine
چکیده انگلیسی

Current commercial sheep vaccines against Mycobacterium avium subspecies paratuberculosis (MAP) are based on the use of live or killed cells from avirulent MAP strains. These stimulate a mixed immune response, featuring both antibody-based and cell-mediated immunity, and can only confer partial protection against Johne's disease but do not prevent infection. This study aimed to identify immune responses in sheep following immunisation with a novel lipid-based live-cell vaccine, drawing comparisons against responses observed to a commercial killed-cell vaccine (Gudair™). The live vaccine was administered either subcutaneously or intra-peritoneally, as either a single-dose vaccine or in an homologous prime-boost protocol. A single-dose of the live vaccine was found to stimulate a cellular immune response similar to that of single-dose Gudair™, but with markedly lower levels of antibody; however, homologous boosting with the live vaccine, by either s.c. or i.p. routes, generated higher levels of MAP-specific antibody. All immunisation regimes tended to decrease the proportion of CD4+ T cells but increase the proportions of γδTCR+ T cells and CD25+ cells in antigen-stimulated ex vivo blood samples. The CD8+:γδTCR+ T cell ratio, thought to represent a reduced regulatory capacity among T cells responding to MAP, was increased among animals receiving either Gudair™ or a single i.p. dose of the live vaccine; however, only the Gudair™ vaccine simultaneously increased the level of lymph node IFNγ mRNA expression, and this treatment also caused a significant elevation in the IFNγ:IL-10 (effector:regulatory) cytokine expression ratio. Thus, among these immunisation regimes, the responses generated by a single s.c. dose of the novel live-cell vaccine appeared to selectively target the CMI-based immune profile thought necessary for control of MAP infection; in contrast, homologous prime-boosting with the live vaccine stimulated a mixed immune response similar to that produced by immunisation with Gudair™.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Veterinary Immunology and Immunopathology - Volume 137, Issues 1–2, 15 September 2010, Pages 109–119
نویسندگان
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