Production of FaeG, the Major Subunit of K88 Fimbriae, in Transgenic Tobacco Plants and Its Immunogenicity in Mice

Transgenic tobacco plants stably expressing recombinant FaeG, which is the major subunit and adhesin of K88ad fimbriae, were obtained. Analysis of sera from immunized mice indicates that in mice, the immunogenicity induced by plant-derived FaeG protein is comparable to that generated with traditional approaches

Intermittent parathyroid hormone (PTH) promotes cementogenesis and alleviates the catabolic effects of mechanical strain in cementoblasts

Abstract Background External root resorption, commonly starting from cementum, is a severe side effect of orthodontic treatment. In this pathological process and repairing course followed, cementoblasts play a significant role. Previous studies implicated that parathyroid hormone (PTH) could act on committed osteoblast precursors to promote differentiation, and inhibit apoptosis. But little was known about the role of PTH in cementoblasts. The purpose of this study was to investigate the effects of intermittent PTH on cementoblasts and its influence after mechanical strain treatment. Results Higher levels of cementogenesis- and differentiation-related biomarkers (bone sialoprotein (BSP), osteocalcin (OCN), Collagen type I (COL1) and Osterix (Osx)) were shown in 1–3 cycles of intermittent PTH treated groups than the control group. Additionally, intermittent PTH increased alkaline phosphatase (ALP) activity and mineralized nodules formation, as measured by ALP staining, quantitative ALP assay, Alizarin red S staining and quantitative calcium assay. The morphology of OCCM-30 cells changed after mechanical strain exertion. Expression of BSP, ALP, OCN, osteopontin (OPN) and Osx was restrained after 18 h mechanical strain. Furthermore, intermittent PTH significantly increased the expression of cementogenesis- and differentiation-related biomarkers in mechanical strain treated OCCM-30 cells. Conclusions Taken together, these data suggested that intermittent PTH promoted cementum formation through activating cementogenesis- and differentiation-related biomarkers, and attenuated the catabolic effects of mechanical strain in immortalized cementoblasts OCCM-30

Versatile prodrug nanoparticles for acid-triggered precise imaging and organelle-specific combination cancer therapy

Integration of chemotherapy with photodynamic therapy (PDT) has been emerging as a novel strategy for treatment of triple negative breast cancer (TNBC). However, the clinical translation of this approach is hindered by the unwanted dark toxicity due to the "always-on" model and low tumor specificity of currently approved photosensitizer (PS). Here, the design of a multifunctional prodrug nanoparticle (NP) is described for precise imaging and organelle-specific combination cancer therapy. The prodrug NP is composed of a newly synthesized oxaliplatin prodrug, hexadecyl-oxaliplatintrimethyleneamine (HOT), an acid-activatable PS, derivative of Chlorin e6 (AC), and functionalized with a targeting ligand iRGD for tumor homing and penetration. HOT displays much higher antitumor efficiency than oxaliplatin by simultaneously inducing mitochondria depolarizing and DNA cross-linking. AC is specifically activated in the orthotopic or metastatic TNBC tumor for fluorescence imaging and PDT, while it remains inert in blood circulation to minimize the dark toxicity. Under the guide of acid-activatable fluorescence imaging, PDT and chemotherapy can be synergistically performed for highly efficient regression of TNBC. Taken together, this versatile prodrug nanoplatform could achieve tumor-specific imaging and organelle-specific combination therapy, which can provide an alternative option for cancer theranostic

Prototropically Allosteric Probe for Superbly Selective DNA Analysis

Selective nucleotide recognition for biosensor evolution requires rational probe design toward the binding-pattern-susceptible readout but without serious poison in selectivity from the context sequences. In this work, we synthesized a dual-function (trihydroxyphenyl)­porphyrin (POH₃) to target the abasic site (AP site) in ds-DNA using the trihydroxyphenyl substituent and the tetrapyrrole macrocycle as the recognition unit (RU) and the fluorescent signal unit (SU), respectively. RU and SU are separated from each other but are prototropically allosteric. We found that an appropriate pH favors formation of the nonfluorescent quinine/pyrrole (O–NH) conformer of POH₃. However, the complementary hydrogen bonding of RU in O–NH with the target cytosine opposite the AP site switches on the SU fluorescence through prototropic allostery toward the phenol/isopyrrole (OH–N) conformer, while the bases thymine, guanine, and adenine totally silence this allostery, suggesting a superb selectivity in single-nucleotide polymorphism (SNP) analysis. The role of the prototropic allostery in achieving such SNP selectivity is also evidenced using porphyrins with other hydroxyl substituent patterns. Because of the SU separation from RU, SU is not directly involved in the interaction with the AP site, and thus, the turn-on selectivity is also realized for DNA with flanking guanine, the most easily oxidized base in DNA. This tolerance to the flanking base identity has seldom been achieved in previous studies. Additionally, other DNA structures cannot bring this allostery, indicating that the combination recipe of the AP site design and the prototropically allosteric probe will find wide applications in DNA-based sensors

From structural design to delivery: mRNA therapeutics for cancer immunotherapy

Abstract mRNA therapeutics have emerged as powerful tools for cancer immunotherapy in accordance with their superiority in expressing all sequence‐known proteins in vivo. In particular, with a small dosage of delivered mRNA, antigen‐presenting cells (APCs) can synthesize mutant neo‐antigens and multi‐antigens and present epitopes to T lymphocytes to elicit antitumor effects. In addition, expressing receptors like chimeric antigen receptor (CAR), T‐cell receptor (TCR), CD134, and immune‐modulating factors including cytokines, interferons, and antibodies in specific cells can enhance immunological response against tumors. With the maturation of in vitro transcription (IVT) technology, large‐scale and pure mRNA encoding specific proteins can be synthesized quickly. However, the clinical translation of mRNA‐based anticancer strategies is restricted by delivering mRNA into target organs or cells and the inadequate endosomal escape efficiency of mRNA. Recently, there have been some advances in mRNA‐based cancer immunotherapy, which can be roughly classified as modifications of the mRNA structure and the development of delivery systems, especially the lipid nanoparticle platforms. In this review, the latest strategies for overcoming the limitations of mRNA‐based cancer immunotherapies and the recent advances in delivering mRNA into specific organs and cells are summarized. Challenges and opportunities for clinical applications of mRNA‐based cancer immunotherapy are also discussed