Animal Parasitic Diseases Laboratory, Building 1040, NEA, ARS, USDA, Beltsville, MD 20705, United States.
Department of Microbiology, Southern Illinois University, United States.
Vaccine. 2018 Feb 14;36(8):1126-1131. doi: 10.1016/j.vaccine.2017.11.014.
The purpose of this study was to determine if conjugating a recombinant Eimeria maxima protein, namely EmaxIMP1, into 20 nm polystyrene nanoparticles (NP) could improve the level of protective immunity against E. maxima challenge infection. Recombinant EmaxIMP1 was expressed in Escherichia coli as a poly-His fusion protein, purified by NiNTA chromatography, and conjugated to 20 nm polystyrene NP (NP-EmaxIMP1). NP-EMaxIMP1 or control non-recombinant (NP-NR) protein were delivered per os to newly-hatched broiler chicks with subsequent booster immunizations at 3 and 21 days of age. In battery cage studies (n = 4), chickens immunized with NP-EMaxIMP1 displayed complete protection as measured by weight gain (WG) against E. maxima challenge compared to chickens immunized with NP-NR. WG in the NP-EMaxIMP1-immunized groups was identical to WG in chickens that were not infected with E. maxima infected chickens. In floor pen studies (n = 2), chickens immunized with NP-EMaxIMP1 displayed partial protection as measured by WG against E. maxima challenge compared to chickens immunized with NP-NR. In order to understand the basis for immune stimulation, newly-hatched chicks were inoculated per os with NP-EMaxIMP1 or NP-NR protein, and the small intestine, bursa, and spleen, were examined for NP localization at 1 h and 6 h post-inoculation. Within 1 h, both NP-EMaxIMP1 and NP-NR were observed in all 3 tissues. An increase was observed in the level of NP-EmaxIMP1 and NP-NR in all tissues at 6 h post-inoculation. These data indicate that 20 nm NP-EmaxIMP1 or NP-NR reached deeper tissues within hours of oral inoculation and elicited complete to partial immunity against E. maxima challenge infection.
本研究旨在确定将重组艾美耳球虫蛋白 EmaxIMP1 缀合到 20nm 聚苯乙烯纳米颗粒（NP）中是否可以提高对艾美耳球虫最大挑战感染的保护免疫水平。重组 EmaxIMP1 在大肠杆菌中作为多组氨酸融合蛋白表达，通过 NiNTA 层析纯化，并与 20nm 聚苯乙烯 NP（NP-EmaxIMP1）缀合。NP-EmaxIMP1 或对照非重组（NP-NR）蛋白通过口服递送至刚孵出的肉鸡雏鸡，随后在 3 天和 21 天龄时进行加强免疫。在电池笼研究中（n=4），与用 NP-NR 免疫的鸡相比，用 NP-EmaxIMP1 免疫的鸡在增重（WG）方面对艾美耳球虫最大挑战的完全保护，这是通过测量获得的。NP-EmaxIMP1 免疫组的 WG 与未感染艾美耳球虫最大感染鸡的 WG 相同。在地板笼研究中（n=2），与用 NP-NR 免疫的鸡相比，用 NP-EmaxIMP1 免疫的鸡在增重（WG）方面对艾美耳球虫最大挑战的部分保护，这是通过测量获得的。为了了解免疫刺激的基础，刚孵出的雏鸡通过口服接种 NP-EmaxIMP1 或 NP-NR 蛋白，在接种后 1 小时和 6 小时检查小肠、法氏囊和脾脏中 NP 的定位。在 1 小时内，NP-EmaxIMP1 和 NP-NR 都在所有 3 种组织中观察到。在接种后 6 小时，所有组织中 NP-EmaxIMP1 和 NP-NR 的水平均增加。这些数据表明，20nm NP-EmaxIMP1 或 NP-NR 在口服接种后数小时内到达更深的组织，并对艾美耳球虫最大挑战感染产生完全至部分免疫。
