Objective To prepare and identify CS-PLGA microspheres carrying bilayer antigen protein.Methods Porous microspheres were prepared by emulsion polymerization combined with solvent evaporation.The antigen was loaded in a water bath at 4 ℃,and the antigen was promoted to enter the microspheres by physical diffusion media-ted by antigen concentration gradient and combined with the outer surface of the microspheres by electrostatic ac-tion,forming an inner and outer double-layer antigen carrier.Then,according to the glass transition temperature of PLGA material,the pores on the surface of porous microspheres were promoted to heal at 48 ℃ to form a closed microsphere preparation,and then the obtained microsphere preparation was suspended with chitosan solution for cationic modification to reverse the negative potential on the surface of microspheres.In this study,the morphology,particle size distribution and potential changes of microspheres were detected by scanning electron microscope and dynamic light scattering particle size analyzer.In addition,sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)was used to identify whether the antigen was loaded into the microsphere preparation.The fluorescent labeled BSA and fluorescent labeled PLGA materials were used to observe the distribution of the antigen after load-ing by laser confocal microscope.The encapsulation efficiency and drug loading rate of the microsphere preparation were detected by BCA method.Results The results of scanning electron microscope and optical microscope showed that the porous microspheres had good pore formation,the particle size was(73.94±0.81)nm,and the Polydisper-sity index was 0.038±0.004.Zeta potential changed from negative to positive,which indicated that chitosan had been successfully coated on the surface of microspheres.SDS-PAGE,laser confocal microscope and other detection methods confirmed that BSA had been successfully carried.The encapsulation rate of porous microspheres was(3.01±0.04)％and the drug loading rate was(1.50±0.02)％after detection by micro BCA kit.Conclusion CS-PLGA preparation carrying bilayer antigen was successfully prepared,which provided a new idea for the subse-quent study of sustained and controlled release preparations.

The aim of this study was to prepare a self-assembled nanoparticle monkeypox vaccine candidate and study its immune response characteristics,so as to provide reference test data for its vaccine design.The antigen protein A29L-SpyTag and the backbone protein Mi3-SpyCatcher were expressed and purified by prokaryotic system,and nanoparticles A29L-Mi3 were prepared by chemical assembly,then the antibody titers were determined by ELISA,the antibody neutralization was determined by plaque test,and the cytokine secretion of lymphocytes was determined by flow cytometry to describe the immune response characteristics.Data showed that A29L-Mi3 nanoparticles were successfully prepared,and the particles were uniformly distributed in hollow cages,with an average particle size of(29±0.19)nm.After the A29L-Mi3 nanoparticle vaccine candidate was combined with SP01 adjuvant,the neutralizing antibody titer was stronger than that of the A29L protein candidate,and the A29L-Mi3 nanoparticle vaccine candidate could obtain neutralizing antibodies with similar titers after two immunizations.The level of mouse T lymphocyte immune response activated by the A29L-Mi3 nanoparticle vaccine candidate was higher than that of the A29L protein vaccine candidate.In conclusion,A29L-Mi3 protein nanoparticles with uniform structure have successfully assembled in vitro,which has strong immunogenicity and improved neutralization ability after combination with SP01 adjuvant,thus provided reference data for the optimization of immune programs.In addition,the level of cellular immune response is higher than that of A29L protein alone,which provides a reference for the design and development of monkeypox vaccine.

N ⁶-methyladenosine (m⁶A) modification is critical for mRNA splicing, nuclear export, stability and translation. Fat mass and obesity-associated protein (FTO), the first identified m⁶A demethylase, is critical for cancer progression. Herein, we developed small-molecule inhibitors of FTO by virtual screening, structural optimization, and bioassay. As a result, two FTO inhibitors namely 18077 and 18097 were identified, which can selectively inhibit demethylase activity of FTO. Specifically, 18097 bound to the active site of FTO and then inhibited cell cycle process and migration of cancer cells. In addition, 18097 reprogrammed the epi-transcriptome of breast cancer cells, particularly for genes related to P53 pathway. 18097 increased the abundance of m⁶A modification of suppressor of cytokine signaling 1 (SOCS1) mRNA, which recruited IGF2BP1 to increase mRNA stability of SOCS1 and subsequently activated the P53 signaling pathway. Further, 18097 suppressed cellular lipogenesis via downregulation of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), and C/EBPβ. Animal studies confirmed that 18097 can significantly suppress in vivo growth and lung colonization of breast cancer cells. Collectively, we identified that FTO can work as a potential drug target and the small-molecule inhibitor 18097 can serve as a potential agent against breast cancer.

Scaffold hopping refers to computer-aided screening for active compounds with different structures against the same receptor to enrich privileged scaffolds, which is a topic of high interest in organic and medicinal chemistry. However, most approaches cannot efficiently predict the potency level of candidates after scaffold hopping. Herein, we identified potent PDE5 inhibitors with a novel scaffold via a free energy perturbation (FEP)-guided scaffold-hopping strategy, and FEP shows great advantages to precisely predict the theoretical binding potencies ΔG _FEP between ligands and their target, which were more consistent with the experimental binding potencies ΔG _EXP (the mean absolute deviations | Δ G FEP - Δ G EXP |  < 2 kcal/mol) than those ΔG _MM-PBSA or ΔG _MM-GBSA predicted by the MM-PBSA or MM-GBSA method. Lead L12 had an IC₅₀ of 8.7 nmol/L and exhibited a different binding pattern in its crystal structure with PDE5 from the famous starting drug tadalafil. Our work provides the first report via the FEP-guided scaffold hopping strategy for potent inhibitor discovery with a novel scaffold, implying that it will have a variety of future applications in rational molecular design and drug discovery.

Our recent studies demonstrated that the natural product nobiletin (NOB) served as a promising multidrug resistance (MDR) reversal agent and improved the effectiveness of cancer chemotherapy . However, low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic agent. To tackle these challenges, NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and efficacy. All the compounds showed improved sensitivity to paclitaxel (PTX) in P-glycoprotein (P-gp) overexpressing MDR cancer cells. Among them, compound exhibited water solubility 280-fold higher than NOB. A drug-resistance A549/T xenograft model showed that at a dose of 50 mg/kg co-administered with PTX (15 mg/kg), inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors P-gp inhibition. Moreover, Western blot experiments revealed that inhibited expression of NRF2, phosphorylated ERK and AKT in MDR cancer cells, thus implying of multiple mechanisms to reverse MDR in lung cancer.

Optimization efforts were devoted to discover novel PDE10A inhibitors in order to improve solubility and pharmacokinetics properties for a long-term therapy against pulmonary arterial hypertension (PAH) starting from the previously synthesized inhibitor

Objective To prepare VP1 protein vaccine of Coxsackievirus A16(CA16) and evalu-ate immunngenicity the subunit vaccines of Coxsackievirus (VP1), and to establish foundation for studying CA16 vaccine. Methods CA16 VP1 was amplified by RT-PCR and cloned into pFastBac HT A plasmid, recombinated with Bacmid DNA by transposition reaction and then transfected Sf9 cell, mixed with adjuvant AI(OH)_3. After immunization BALB/c mice, evaluating immune effectiveness after booster injections 2 weeks. Results The expressed protein was analyzed by SDS-PAGE and Western blot, mice immunized with CA16 (VP1) both induced specific IgG antibody and neutralization antibody. The best immunization antigen was 20 μg, IgG antibody was 1: 1600, neutralization antibody was 1:250, typical Th1/Th2 immune response was determined by lymphocyte proliferation assay and cytokine analysis. Conclusion The CA16 VP1 gene was cloned successfully and expressed in Sf9 insect cells, CA16 VP1 protein vaccine induced both humoral and cellular immune response, to lay solid foundation for further study on CA16 vaccine.

A cold-adapted (ca), temperature sensitive (ts), live attenuated influenza B virus strain B/Ann Arbor/1/66 was chosen for influenza virus rescue research, in which six internal gene segments, PB1, PB2, PA, NP, M, NS, were fully synthesized and nine amino acid substitutions were artificially alter by human intervention. The resultant B/Ann Arbor/1/66 plasmids were named as pAB121-PB1, pAB122-PB2, pAB123-PA, pAB124-HA, pAB125-NP, pAB126-NA, pAB127-M and pAB128-NS, respectively. A recombinant influenza A virus was previously generated entirely from cloned cDNA. An infectious recombinant influenza B virus was generated here, and designated as rMDV-B, by plasmid-based reverse genetics. The rMDV-B virus contained HA and NA genes from an epidemic influenza B vires strain B/Malaysia/2506/2004 in the background of internal genes derived from influenza B virus strain B/Ann Arbor/1/66. HA titer of rMDV-B in MDCK cells and embryonated chicken eggs ranged from 1 : 64 to 1 : 512. The results may allow an effective live influenza B vaccine to be produced from a single master strain, providing a model for the design of future live human influenza vaccines.

Objective To set up a technical platform of reverse genetics based on the 8 plasmid.virus rescue system of cold-adapted influenza virus strain. Methods The cold-adapted, temperature sensitive, live attenuated influenza virus strain A/AnnArbor/6/60(H2N2)was chosen as the master donor virus(MDV)for rescue research,and its six internal gene fragments PB2,PB1,PA,NP,M and NS were artificially synthesized. Meanwhile, five amino acid mutations have been introduced as tags. Six fragments were ligated with modified pAD3000 for the construction of rescue plasmid. Six transcription/expression plasmids(pMDV-A-PB2,pMDV-A-PB1,pMDV-A-PA,pMDV-A-NP,pMDV-A-M,and pMDV-A-NS)were obtained, and their sequences were accurate. Results The reassorted virus named as rMDV-A contains HA and NA gene segments derived from PR8 strain along with six gene segments,PB2,PB1,PA,NP,M and NS,from MDV. The COS-1 cells were co-transfected with eight recombinant plasmids. The results showed that a cold-adapted, attenuated reassortant influenza A virus with hemagglutination activity was rescued successfullv bv"6+2" combination of MDV and PR8, and the allanotoic fluid of the injected eggs gave a posigenes of A/AA/6/60 used as backbone has provided experimental materials for further research on the gene function and novel vaccine candidate of cold-adapted, attenuated human influenza virus.

Six gene segments,PB1,PB2,PA,NP,M and NS,were fully synthesized which derived from the master donor virus (MDV),cold-adapted(ca),temperature sensitive(ts),live attenuated influenza virus strain A/Ann Arbor/6/60(MDV-A).Meanwhile,five amino acid substitutions (PB1-391E,58lG,661T,PB2-265S,NP-34G) were artificially altered by human intervention.HA and NA fragments derived from the 2006-2007 circulating strain A/New Caledonia/20/99 (H1N1).Eight fragments were ligated with modified pAD3000 for rescue plasmid construction.Eiight transcription/expression plasmids were named as pMDV-A-PB2,pMDV-A-PB1,pMDV-A-PA,pMDV-A-NP,pMDV-A-M,pMDV-A-NS,pMDV-A-HA,pMDV-A-NA,respectively.The COS-l cells were co-transfected with eight plasmids representing 6 internal viral backbone of the strain A/AA/6/60 and two plasmids containing the CDNA of the HA and NA segments of the strain A/New Caledonia/20/99 (H1N1),the results showed that cold-adapted,attenuated reassortant influenza A virus Was rescued successfully.Titers of a reassorted influenza A virus in embryonated chicken eggs mnged from 1:29to l:210.The rescue system of six intemal genes used as backbone opens the way for further research on gene function and neotype vaccine candidate of cold-adapted,live attenuated human influenza virus.