Fowl typhoid (FT) caused by Salmonella Gallinarum (SG) is a poultry disease distributed worldwide that has been eradicated in commercial production of many developed countries but still persists in many developing countries. Vaccination is one of the main strategies to reduce mortality, clinical signs, and vertical or horizontal transmission. The aim of this work was to assess the protection against FT conferred by vaccines based on Salmonella Enteritidis (SE), SG, or a combination. Five experimental groups of birds, vaccinated with different live or inactivated SG and SE vaccines were included in the trial: 1) two doses of a SG-SE bivalent inactivated vaccine; 2) four doses of the live attenuated SE vaccine; 3) three doses of the live attenuated SE vaccine and two doses of the SG-SE bivalent inactivated vaccine; 4) two doses of the live attenuated SG9R vaccine; and 5) unvaccinated birds. At 28 wk of age, all hens were challenged with a virulent strain of SG, and mortality was recorded during the subsequent 15 days. The results showed that the plan that included only the inactivated vaccine did not show significant protection (P = 1), while the plan based on the administration of the attenuated strain of SE significantly reduced mortality in the group of birds (P = 0.0309). However, the highest levels of protection were obtained in the group of hens immunized with the combination of the inactivated vaccine and the live attenuated SE strain (P < 0.0001), which was statistically similar to the homologous protection conferred by the SG 9R strain, a vaccine used in many countries to control FT. These results demonstrate that the combination of existing vaccines together with strict biosecurity measures on farms may help improve the control of the pathogen in countries where FT in an emerging or reemerging disease.

2024-03-11·Human vaccines & immunotherapeutics3区 · 医学

Vaccination of pregnant rhesus monkeys with inactivated rotavirus as a model for achieving protection from rotavirus SA11 infection in the offspring

3区 · 医学

Article

作者: Wu, Jinyuan ; He, Zhanlong ; Yi, Shan ; Li, Hongjun ; Zhou, Yan ; Yin, Na ; Lin, Xiaochen ; Sun, Maosheng ; Chen, Rong ; Liu, Yaling ; Kuang, Xiangjing ; Ye, Jun ; Hu, Xiaoqing

Live-attenuated rotavirus vaccine has shown low protection in underdeveloped or developing countries. However, the inactivated rotavirus vaccine may have the potential to overcome some of these challenges. In the present study, the immunogenicity and protective efficacy of a bivalent inactivated rotavirus vaccine by parenteral administration were elevated in a neonatal rhesus monkey model. A bivalent inactivated rotavirus vaccine containing G1P[8] (ZTR-68 strain) and G9P[8] (ZTR-18 strain) was administered to pregnant rhesus monkeys twice at an interval of 14 days. Neutralizing antibodies against RV strains ZTR-68, ZTR-18, SA11, WA, UK, and Gottfried emerged in pregnant rhesus monkeys and were transplacentally transmitted to the offspring. In the vaccine group, clinical symptoms of diarrhea, viral load in the gut tissue and histopathological changes were significantly reduced in the neonatal rhesus monkeys following oral challenge with the SA11 strain.

2023-12-31·Drug delivery

Oral delivery of bi-autoantigens by bacterium-like particles (BLPs) against autoimmune diabetes in NOD mice

Article

作者: Mao, Ruifeng ; Wu, Mengmeng ; Li, Dengchao ; Chang, Xin ; Chi, Zhenjing ; Mao, Lixia ; Diao, Enjie ; Wang, Yefu ; Xu, Ying ; Zhang, Tong ; Chen, Yingying ; Wang, Jin ; Wang, Yuqi

Induction of oral tolerance by vaccination with type 1 diabetes mellitus (T1DM)-associated autoantigens exhibits great potential in preventing and treating this autoimmune disease. However, antigen degradation in the gastrointestinal tract (GIT) limits the delivery efficiency of oral antigens. Previously, bacterium-like particles (BLPs) have been used to deliver a single-chain insulin (SCI-59) analog (BLPs-SCI-59) or the intracellular domain of insulinoma-associated protein 2 (IA-2ic) (BLPs-IA-2ic). Both monovalent BLPs vaccines can suppress T1DM in NOD mice by stimulating the corresponding antigen-specific oral tolerance, respectively. Here, we constructed two bivalent BLPs vaccines which simultaneously deliver SCI-59 and IA-2ic (Bivalent vaccine-mix or Bivalent vaccine-SA), and evaluated whether there is an additive beneficial effect on tolerance induction and suppression of T1DM by treatment with BLPs-delivered bi-autoantigens. Compared to the monovalent BLPs vaccines, oral administration of the Bivalent vaccine-mix could significantly reduce morbidity and mortality in T1DM. Treatment with the bivalent BLPs vaccines (especially Bivalent vaccine-mix) endowed the mice with a stronger ability to regulate blood glucose and protect the integrity and function of pancreatic islets than the monovalent BLPs vaccines treatment. This additive effect of BLPs-delivered bi-autoantigens on T1DM prevention may be related to that SCI-59- and IA-2-specific Th2-like immune responses could be induced, which was more beneficial for the correction of Th1/Th2 imbalance. In addition, more CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) were induced by treatment with the bivalent BLPs vaccines than did the monovalent BLPs vaccines. Therefore, multiple autoantigens delivered by BLPs maybe a promising strategy to prevent T1DM by efficiently inducing antigen-specific immune tolerance.

100 项与双价肾综合征出血热灭活疫苗 (无锡罗益生物) 相关的药物交易

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