Polysaccharide from Atractylodes macrocephala Koidz Binding with Zinc Oxide Nanoparticles as a Novel Mucosal Immune Adjuvant for H9N2 Inactivated Vaccine.

H9N2 avian influenza poses a significant public health risk, necessitating effective vaccines for mass immunization. Oral inactivated vaccines offer advantages like the ease of administration, but their efficacy often requires enhancement through mucosal adjuvants. In a previous study, we established a novel complex of polysaccharide from Atractylodes macrocephala Koidz binding with zinc oxide nanoparticles (AMP-ZnONPs) and preliminarily demonstrated its immune-enhancing function. This work aimed to evaluate the efficacy of AMP-ZnONPs as adjuvants in an oral H9N2-inactivated vaccine and the vaccine's impact on intestinal mucosal immunity. In this study, mice were orally vaccinated on days 0 and 14 after adapting to the environment. AMP-ZnONPs significantly improved HI titers, the levels of specific IgG, IgG1 and IgG2a in serum and sIgA in intestinal lavage fluid; increased the number of B-1 and B-2 cells and dendritic cell populations; and enhanced the mRNA expression of intestinal homing factors and immune-related cytokines. Interestingly, AMP-ZnONPs were more likely to affect B-1 cells than B-2 cells. AMP-ZnONPs showed mucosal immune enhancement that was comparable to positive control (cholera toxin, CT), but not to the side effect of weight loss caused by CT. Compared to the whole-inactivated H9N2 virus (WIV) group, the WIV + AMP-ZnONP and WIV + CT groups exhibited opposite shifts in gut microbial abundance. AMP-ZnONPs serve as an effective and safe mucosal adjuvant for oral WIV, improving cellular, humoral and mucosal immunity and microbiota in the gastrointestinal tract, avoiding the related undesired effects of CT.

The inhibition effect of caffeic acid on NOX/ROS-dependent macrophages M1-like polarization contributes to relieve the LPS-induced mice mastitis.

The mammary gland is an adipose tissue containing not only adipocytes but also epithelial, endothelial, and immune cells. Epithelial cells and macrophages, as the integral components of the immune system, are on the front line of defense against infection. Our preliminary work proved that caffeic acid (CA) can effectively inhibit the inflammatory cascade of bovine mammary epithelial cells (BMEC) induced by lipopolysaccharide (LPS) and maintain cellular integrity and viability. Here, we investigated the therapeutic effect of CA on LPS-induced mice mastitis and explored its regulatory mechanism on macrophage inflammatory response induced by LPS in vitro. Firstly, the mice mastitis model was established by intramammary injection with 10 µg LPS, after which different CA doses (5, 10, 15 mg/kg) were administered. Then, the pathological section, myeloperoxidase (MPO) activity, proinflammatory factors and chemokines releasement, and redox state of mammary tissues were assessed, confirming CA's effectiveness on mice mastitis. In vitro, we validated the therapeutic relevance of CA in relieving LPS-induced RAW264.7 inflammatory and oxidative stress responses. Moreover, we further provided evidence that CA significantly reduced LPS-induced reactive oxygen species (ROS) generation via NADPH oxidase (NOX), which improved the imbalance relationship between nuclear factor kappa-B (NF-κB) and NF-E2 p45-related factor 2 (Nrf2) and led to a marked weakening of M1 polarization. The NOX-ROS signal inhibited by CA weakened the oxidative burst and neutrophil chemotaxis of macrophages, thus alleviating the immune cascade in mammary gland tissue and reducing the LPS-induced inflammatory damage. Collectively, CA would be a potential candidate or antibacterial synergist for curbing mastitis.

Therapeutic effect of a self-made herbal formula on a multi-drug resistant Eimeria tenella isolate infection in broiler chickens.

In-feed prophylactic chemotherapy is widely considered the mainstay of avian coccidiosis control, while serious drug resistance strictly restricts its application. Confronted with the urgent need for an alternative strategy, a traditional Chinese medicine formula (TCMF) was developed. Meanwhile, its potential to iron out complicated clinical coccidiosis was scrutinized in vivo with a field-isolated multi-drug resistant Eimeria tenella (E. tenella) isolate. Birds were inoculated with 5 × 104 sporulated oocysts and administrated with TCMF supplementation in water from 72 h post-infection to the end of the experiment, diclazuril (DIC) was set as a positive control. As a result, TCMF intervention reduced oocyst shedding, cecal lesion and mortality, and enhanced body weight gain. According to the above, anticoccidial index (ACI) was calculated and TCMF exerted a moderate anticoccidial activity. Besides, macroscopic, histopathological, and ultrastructural observations revealed the safeguarding effects of TCMF on E. tenella-induced cecal injury. Following, TCMF treatment presented an obvious inhibition effect on E. tenella caused oxidative stress and inflammatory response. Moreover, TCMF supplementation restored the cecal flora abundance and diversity, reduced the colonization of harmful bacteria, and increased the probiotics abundance. In conclusion, TCMF exhibited a moderate anticoccidial effect along with alleviating E. tenella-induced cecal injury, redox imbalance, and inflammatory response which may be associated with the microflora modulatory effect.

The effects of fluoroalkyl chain length and density on siRNA delivery of bioreducible poly(amido amine)s.

Fluorination is an attractive strategy for the improvement of transfection efficiency of nucleic acid delivery vectors. Bioreducible poly(amido amine)s (bPAAs) are an important class of biomaterials exhibited to effectively deliver multiple nucleic acids. However, still, the effects of fluoroalkyl chain length and density of bPAA on siRNA delivery are unveiled. Here, we synthesized bPAAs and grafted with different chain lengths and densities of fluorocarbon compounds. Furthermore, we prepared a library of complexes of fluorinated bPAA and siRNA, and investigated the effects of fluorination on the siRNA delivery in vitro and in vivo. We found that all the synthesized bPAAs readily formed complexes with siRNA and the fluorinated complexes considerably achieved improved gene silencing efficacies both in vitro and in vivo. Dramatically, the gene silencing efficacy was increased with increasing fluorine contents. Heptafluorobutyric anhydride (HF) modified bPAAs achieved better gene silencing efficacy when compared with bPAAs fluorinated by trifluoroacetic anhydride (TF) and pentafluoropropionic anhydride (PF) providing the evidence for choosing of best one among fluorocarbon compounds. In addition, a combination of fluorination with bioreducibility enables efficient and safe siRNA delivery.