Protective Efficacy Induced by the Common Eimeria Antigen Elongation Factor 2 against Challenge with Three Eimeria Species in Chickens.

Avian coccidiosis arises from co-infection involving multiple Eimeria species, which could give rise to substantial economic losses in the global poultry industry. As a result, multivalent anticoccidial vaccines containing common Eimeria antigens offer considerable promise for controlling co-infection in clinical practice. In our previous study, Elongation factor 2 (EF2) was deemed as an immunogenic common antigen across various Eimeria species. This current investigation aimed to further assess the immunogenicity and protective efficacy of EF2 in recombinant subunit vaccine format against three Eimeria species. The EF2 gene cloned from Eimeria maxima (E. maxima) cDNA was designated as EF2 of E. maxima (EmEF2). The immunogenicity of the recombinant protein EmEF2 (rEmEF2) was assessed through Western blot analysis. The evaluation of the vaccine-induced immune response encompassed the determination of T lymphocyte subset proportions, cytokine mRNA transcription levels, and specific IgY concentrations in rEmEF2-vaccinated chickens using flow cytometry, quantitative real-time PCR (qPCR), and indirect enzyme-linked immunosorbent assay (ELISA). Subsequently, the protective efficacy of rEmEF2 was evaluated through vaccination and challenge experiments. The findings demonstrated that rEmEF2 was effectively recognized by the His-tag monoclonal antibody and E. maxima chicken antiserum. Vaccination with rEmEF2 increased the proportions of CD4+ and CD8+ T lymphocytes, elevated IL-4 and IFN-γ mRNA transcription levels, and enhanced IgY antibody levels compared to the control groups. Moreover, compared to the control groups, vaccination with rEmEF2 led to decreased weight loss, reduced oocyst outputs, and alleviated enteric lesions. Furthermore, in the rEmEF2-immunized groups, challenges with E. maxima and E. acervulina resulted in anticoccidial index (ACI) scores of 166.35 and 185.08, showing moderate-to-excellent protective efficacy. Nevertheless, challenges with E. tenella and mixed Eimeria resulted in ACI scores of 144.01 and 127.94, showing low protective efficacy. In conclusion, EmEF2, a common antigen across Eimeria species, demonstrated the capacity to induce a significant cellular and humoral immune response, as well as partial protection against E. maxima, E. acervulina, and E. tenella. These results highlight EmEF2 as a promising candidate antigen for the development of multivalent vaccines targeting mixed infections by Eimeria species.

Optimization and evaluation of resveratrol amorphous solid dispersions with a novel polymeric system.

The preparation of amorphous solid dispersions using polymers is a commonly used formulation strategy for enhancing the solubility of poorly water-soluble drugs. However, a single polymer often does not bring significantly enhance the solubility or amorphous stability of a poorly water-soluble drug. We found an application of a unique and novel binary polymeric blend in the preparation of solid dispersions. The main purpose of this study is to optimize and evaluate resveratrol (Res) amorphous solid dispersions with a novel polymeric system of poly (vinyl pyrrolidone) (PVP) and carboxymethyl chitosan (CMCS). The influence of three different release factors, the ratio of CMCS to the polymer mixture (CMCS% = X1), the ratio of Res to the polymer mixture (Res% = X2) and the surfactant (Tween 80 = X3), on the characteristics of released Res at various times (Q5 and Q30) was investigated. The computer optimization and contour plots were used to predict the levels of the independent variables as X1 = 0.17, X2 = 0.10 and X3 = 2.94 for maximized responses of Q5 and Q30. Fourier transform infrared spectroscopy (FTIR) results revealed that each polymer formed hydrogen bonds with Res. The solid performance and physical stability of the optimized ternary dispersions were studied with scanning electron microscopy (SEM), powder X-ray diffraction (XRD), modulated differential scanning calorimetry (MDSC) and dissolution testing. SEM, XRD and MDSC analysis demonstrated that the Res was amorphous, and MDSC showed no evidence of phase separation during storage. Dissolution testing indicated a more than fourfold increase in the apparent solubility of the optimized ternary dispersions, which maintained high solubility after 90 days. In our research, we used CMCS as a new carrier in combination with PVP, which not only improved the in vitro dissolution of Res but also had better stability.