کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5545394 1555318 2017 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Preexisting Salmonella-specific immunity interferes with the subsequent development of immune responses against the Salmonella strains delivering H9N2 hemagglutinin
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Preexisting Salmonella-specific immunity interferes with the subsequent development of immune responses against the Salmonella strains delivering H9N2 hemagglutinin
چکیده انگلیسی


- Salmonella delivering H9N2 hemagglutinin (HA) efficiently stimulate HA-specific immune responses.
- Carrier-specific immunity interferes with the subsequent development of antigen-specific immune responses.
- Preexisting immunity could be avoided by selecting the time point when carrier-specific immunity is relatively low.

Recombinant Salmonella strains expressing foreign heterologous antigens have been extensively studied as promising live vaccine delivery vehicles. In this study, we constructed attenuated smooth (S-HA) and rough (R-HA) Salmonella strains expressing hemagglutinin (HA) of H9N2, a low pathogenic avian influenza A virus. We then investigated the HA-specific immune responses following oral immunization with either S-HA or R-HA strain in chicken model. We further examined the effects of the preexisting anti-Salmonella immunity on the subsequent elicitation of the HA and the Salmonella ompA specific immune responses. Our results showed that primary immunization with either the S-HA or the R-HA strain elicited comparable HA-specific immune responses and the responses were significantly (p < 0.05) higher compared to the Salmonella vector control. When chickens were pre-immunized with the smooth Salmonella carrier alone and then vaccinated with either S-HA or R-HA strain 3, 6 and 9 weeks later, respectively, significant reductions were seen for HA-specific immune responses at week 6, a point which corresponded to the peak of the primary Salmonella-specific antibody responses. No reductions were seen at week 3 and 9, albeit, the HA-specific immune responses were boosted at week 9, a point which corresponded to the lowest primary Salmonella-specific antibody responses. The ompA recall responses remain refractory at week 3 and 6 following deliberate immunization with the carrier strain, but were significantly (p < 0.05) increased at week 9 post-primary immunization. We conclude that preexisting anti-Salmonella immunity inhibits antigen-specific immune responses and this effect could be avoided by carefully selecting the time point when carrier-specific immune responses are relatively low.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Veterinary Microbiology - Volume 205, June 2017, Pages 117-123
نویسندگان
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