Humoral and cellular immune responses induced by serogroup W135 meningococcal conjugate and polysaccharide vaccines.

Investigating the mechanisms by which W135 meningococcal conjugate (PSW135-TT) activates adaptive immune responses in mice can provide a comprehensive understanding of the immune mechanisms of bacterial polysaccharide conjugate vaccines. We compared B-cell and T-cell immune responses immunized with W135 meningococcal capsular polysaccharides (PSW135), tetanus toxoid (TT) and PSW135-TT in mice. The results showed that PSW135-TT could induce higher PSW135-specific and TT-specific IgG antibodies with a significant enhancement after two doses.

The application of nanoparticles in point-of-care testing (POCT) immunoassays.

The Covid-19 pandemic has led to greater recognition of the importance of the fast and timely detection of pathogens. Recent advances in point-of-care testing (POCT) technology have shown promising results for rapid diagnosis. Immunoassays are among the most extensive POCT assays, in which specific labels are used to indicate and amplify the immune signal.

Bio-mineralization of virus-like particles by metal-organic framework nanoparticles enhances the thermostability and immune responses of the vaccines.

Virus-like particle (VLPs) vaccines have been extensively studied due to their good immunogenicity and safety; however, they highly rely on cold-chain storage and transportation. Nanotechnology of bio-mineralization as a useful strategy has been employed to improve the thermal stability and immunogenicity of VLPs. A zeolitic imidazole framework (ZIF-8), a core-shell structured nanocomposite, was applied to encapsulate foot-and-mouth disease virus (FMDV) VLPs.

Flower-like mesoporous silica nanoparticles as an antigen delivery platform to promote systemic immune response.

Virus-like particles (VLPs), a kind of superior subunit vaccine, are assembled from the viral structural proteins with similar capsids to viruses. However, the efficiency of cell uptake is not satisfactory. We prepared flower-like mesoporous silica nanoparticles (SiNPs) with large pore channels and interior cavities to solve the problem.

Biomimetic and cell-mediated mineralization of hydroxyapatite by carrageenan functionalized graphene oxide.

In bone tissue engineering, it is imperative to design multifunctional biomaterials that can induce and assemble bonelike apatite that is close to natural bone. In this study, graphene oxide (GO) was functionalized by carrageenan. The resulting GO-carrageenan (GO-Car) composite was further used as a substrate for biomimetic and cell-mediated mineralization of hydroxyapatite (HA).

Selective off-on fluorescent chemosensor for detection of Fe3+ ions in aqueous media.

A Fe(3+) chemosensor L1 was successfully synthesized with a quinoline moiety bound to rhodamine 6G hydrazide. The sensor L1 shows high selectivity and sensitivity to Fe(3+) in aqueous solution in the presence of other trace metal ions in organisms, abundant cellular cations and prevalent toxic metal ions in the environment. In addition, biological imaging and micro computed tomography (MCT) technology studies have demonstrated that L1 could act as a turn-on fluorescent chemosensor for Fe(3+) in living cells.

Recognition of copper and hydrogen sulfide in vitro using a fluorescein derivative indicator.

We report the development of a fluorescein-based chemosensor (L1) for monitoring ions or micromolecules (H(2)S). Copper ions are known to be toxic at high concentrations and hydrogen sulfide induces various problems. Herein we develop a simple method for detecting Cu(II) and H(2)S with high selectivity and sensitivity.

A retrievable and highly selective fluorescent probe for monitoring sulfide and imaging in living cells.

A novel selective fluorescent chemosensor based on an 8-hydroxyquinoline-appended fluorescein derivative (L1) was synthesized and characterized. Once combined with Cu(2+), it displayed high specificity for sulfide anion. Among the various anions, only sulfide anion induced the revival of fluoresecence of L1, which was quenched by Cu(2+), resulting in "off-on"-type sensing of sulfide anion.

Cu(2+)-selective fluorescent chemosensor based on coumarin and its application in bioimaging.

A new fluorescent sensor L1 based on coumarin was synthesized. It shows high sensitivity and selectivity toward Cu(2+) in aqueous solution. The complexation mode and corresponding quenching mechanism were elucidated by ESI-MS and DFT calculations.

A rhodamine-based "turn-on" fluorescent chemodosimeter for Cu2+ and its application in living cell imaging.

A new fluorescent probe 1, N-(Rhodamine-6G)lactam-hydrazinecarbothioamide, was synthesized as a fluorescent and colorimetric chemodosimeter in aqueous solution for Cu(2+). Following Cu(2+)-promoted ring opening, redox and hydrolysis reactions, comparable amplifications of absorption and fluorescence signals were observed upon addition of Cu(2+); this suggests that chemodosimeter 1 effectively avoided the fluorescence quenching caused by the paramagnetic nature of Cu(2+). Importantly, 1 can selectively recognize Cu(2+) in aqueous media in the presence of other trace metal ions in organisms, abundant cellular cations and the prevalent toxic metal ions in the environment with high sensitivity (detection limit <3 ppb) and a rapid response time (<2 min).