Orchestrated Codelivery of Peptide Antigen and Adjuvant to Antigen-Presenting Cells by Using an Engineered Chimeric Peptide Enhances Antitumor T-Cell Immunity.

The intrinsic pharmacokinetic limitations of traditional peptide-based cancer vaccines hamper effective cross-presentation and codelivery of antigens (Ag) and adjuvants, which are crucial for inducing robust antitumor CD8+ T-cell responses. In this study, we report the development of a versatile strategy that simultaneously addresses the different pharmacokinetic challenges of soluble subunit vaccines composed of Ags and cytosine-guanosine oligodeoxynucleotide (CpG) to modulate vaccine efficacy via translating an engineered chimeric peptide, eTAT, as an intramolecular adjuvant. Linking Ags to eTAT enhanced cytosolic delivery of the Ags. This, in turn, led to improved activation and lymph node-trafficking of Ag-presenting cells and Ag cross-presentation, thus promoting Ag-specific T-cell immune responses. Simple mixing of eTAT-linked Ags and CpG significantly enhanced codelivery of Ags and CpG to the Ag-presenting cells, and this substantially augmented the adjuvant effect of CpG, maximized vaccine immunogenicity, and elicited robust and durable CD8+ T-cell responses. Vaccination with this formulation altered the tumor microenvironment and exhibited potent antitumor effects, with generally further enhanced therapeutic efficacy when used in combination with anti-PD1. Altogether, the engineered chimeric peptide-based orchestrated codelivery of Ag and adjuvant may serve as a promising but simple strategy to improve the efficacy of peptide-based cancer vaccines.

Characterization of Monoclonal Antibodies Recognizing Citrulline-Modified Residues.

Background: Citrullination is a post-translational protein modification linked to the occurrence and development of a variety of diseases. The detection of citrullinated proteins is predominately based on antibody detection although currently available reagents demonstrate detection bias according to the environmental context of the citrullinated residues. This study aimed to develop improved antibody reagents capable of detecting citrullinated residues in proteins in an unbiased manner. Methods: BALB/c mice were sequentially immunized using citrulline conjugates with different carrier proteins, and specific monoclonal antibodies (mAbs) identified by primary screening using citrulline-conjugated proteins unrelated to the immunogen. Secondary screening was performed to identify mAbs whose reactivity could be specifically blocked by free citrulline, followed by identification and performance assessment. Results: Two mAbs, 22F1 and 30G2, specifically recognizing a single citrulline residue were screened from 22 mAbs reacting with citrulline conjugates. Compared with commercially available anti-citrulline antibodies (AB6464, AB100932 and MABN328), 22F1 and 30G2 demonstrated significantly higher reactivity as well as a broader detection spectrum against different citrullinated proteins. 22F1 and 30G2 also had higher specificity than commercial antibodies and overall better applicability to a range of different immunoassays. Conclusion: Two mAbs specifically recognizing a single citrulline residue were successfully produced, each possessing good specificity against different citrullinated proteins. The improved utility of these reagents is expected to make a strong contribution to protein citrullination-related research.

[Advances of targeted protein degradation technology and its applications in diseases therapy].

Targeted protein degradation (TPD) technology facilitates specific and efficient degradation of disease-related proteins through hijacking the two major protein degradation systems in mammalian cells: ubiquitin-proteasome system and lysosome pathway. Compared with traditional small molecule-inhibitors, TPD-based drugs exhibit the characteristics of a broader target spectrum. Compared with techniques interfere with protein expression on the gene and mRNA level, TPD-based drugs are target-specific, efficaciously rapid, and not constrained by post-translational modification of proteins. In the past 20 years, various TPD-based technologies have been developed. Most excitingly, two TPD-based therapeutic drugs have been approved by FDA for phase Ⅰ clinical trials in 2019. Despite of the early stage characteristics and various obstructions of the TPD technology, it could serve as a powerful tool for the development of novel drugs. This review summarizes the advances of different degradation systems based on TPD technologies and their applications in disease therapy. Moreover, the advantages and challenges of various technologies were discussed systematically, with the aim to provide theoretical guidance for further application of TPD technologies in scientific research and drug development.

Efficient intracellular delivery of proteins by a multifunctional chimaeric peptide in vitro and in vivo.

Protein delivery with cell-penetrating peptide is opening up the possibility of using targets inside cells for therapeutic or biological applications; however, cell-penetrating peptide-mediated protein delivery commonly suffers from ineffective endosomal escape and low tolerance in serum, thereby limiting in vivo efficacy. Here, we present an intracellular protein delivery system consisting of four modules in series: cell-penetrating peptide, pH-dependent membrane active peptide, endosome-specific protease sites and a leucine zipper. This system exhibits enhanced delivery efficiency and serum tolerance, depending on proteolytic cleavage-facilitated endosomal escape and leucine zipper-based dimerisation. Intravenous injection of protein phosphatase 1B fused with this system successfully suppresses the tumour necrosis factor-α-induced systemic inflammatory response and acetaminophen-induced acute liver failure in a mouse model. We believe that the strategy of using multifunctional chimaeric peptides is valuable for the development of cell-penetrating peptide-based protein delivery systems, and facilitate the development of biological macromolecular drugs for use against intracellular targets.

Late-Night Eating-Induced Physiological Dysregulation and Circadian Misalignment Are Accompanied by Microbial Dysbiosis.

SCOPE: Irregular eating habits, such as late-night eating, will cause increased risk of obesity and other metabolic diseases. The aim of this study is to elucidate the impacts of late-night eating on physiological function and gut microbiota. METHODS AND RESULTS: Male Wistar rats under 16 h/8 h-light/dark cycle are divided into four groups with specific dietary habits, which mimicked breakfast, lunch, dinner, and late-night eating. Late-night eating, including skipping dinner for a night eating (BLN) and skipping breakfast and having a night eating (LDN), causes an increase of body weight, which is associated with decreased physical activity. Additionally, late-night eating results in hepatic lipid accumulation and systemic inflammation in peripheral tissues, compared to those of free feeding (FF) or breakfast, lunch, and dinner (BLD) groups. The phases of key clock genes are similar in FF, BLD, and BLN groups, while LDN feeding causes an overall 4 h phase delay in peripheral tissues. Moreover, late-night eating, especially LDN feeding, results in a significant alternation in the compositions and functions of gut microbiota, which further contributes to the development of metabolic disorder. CONCLUSION: Late-night eating causes physiological dysregulation and misalignment of circadian rhythm, together with microbial dysbiosis.

Lactobacillus and Bifidobacterium Improves Physiological Function and Cognitive Ability in Aged Mice by the Regulation of Gut Microbiota.

SCOPE: Age-related degeneration is associated with imbalances of gut microbiota and its related immune system, thus gut microbiota dysbiosis is considered to be a key target to improve senescence. The potential roles of probiotics on physiological function and cognitive ability in aged mice are investigated in this study. METHODS AND RESULTS: Lactobacillus casei LC122 or Bifidobacterium longum BL986, are orally administrated for 12 weeks, and the anti-aging effects, as well as the composition and function of gut microbiota, are investigated in aged mice. Probiotics supplementation ameliorates hepatic lipid accumulation, enhances muscle strength and function, attenuates oxidative stress and inflammation in peripheral tissues, and improves gut barrier function. These results are associated with improved learning and memory ability as assessed by behavioral tests and upregulation of neurodegenerative and neurotrophic factors expressions in hippocampus. Moreover, the diversity and composition of gut microbiota are altered in aged mice, and both probiotics treatment display distinguished features of gut microbiota. Comparisons of two probiotic strains reveal significant differences in the taxa at family and genus level, leading to the functional profile change of the microbial community. CONCLUSION: L. casei LC122 and B. longum BL986 might be used as novel and promising anti-aging agents in human.