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Background: Chimeric antigen receptor (CAR) T-cell therapy is practical in treating cancers of hematopoietic origin, but of that in solid tumors compromises efficacy for the loss of the antigen recognized by the CAR. However, dendritic cell (DC)/tumor fusion vaccines present a spectrum of known or unknown tumor antigens to stimulate T cell expansion and enhanced T cell response. Developing a new strategy of enhanced nanobody-based CAR-T (Nb-CAR-T) cells antitumor activity by DC/tumor fusion vaccines stimulation would provide guidance for more effective CAR-T cell therapies. Methods: Considering the therapeutic potential of nanobody (Nb), we first screened EGFRvIII Nb, then constructed and verified the function of EGFRvIII Nb-CAR-T cells in vitro and in vivo. We further combined DC/tumor fusion vaccines to boost EGFRvIII Nb-CAR-T cells antitumor effect, which was evaluated in vitro Nb-CAR-T cell function and in the tumor-bearing xenograft mouse models. Results: We had for the first time successfully selected EGFRvIII Nb for the generation of the novel EGFRvIII Nb-CAR-T cells. Importantly, our results suggested that DC/tumor fusion vaccines stimulate Nb-CAR-T cells response not only in improving T cell proliferation, T cell activation, cytokine secretion and tumor-specific cytotoxicity in vitro, but also significantly reducing tumor burden, prolonging survival and improving Nb-CAR-T cells infiltration. Conclusions: We have innovatively shown that DC/tumor fusion vaccines significantly enhance the efficacy of Nb-CAR-T cells against solid tumors. This new strategy has provided a promising therapeutic platform for promoting the clinical treatment of CAR-T cells therapy.

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an infectious disease that has become a serious burden on global public health. This study screened and yielded specific nanobodies (Nbs) against SARS-CoV-2 spike protein receptor binding domain (RBD), following testing its basic characteristics. A nanobody phage library was established by immunizing a camel with RBD protein. After three rounds of panning, the positive colonies were screened by enzyme-linked immunosorbent assay (ELISA). By sequencing, four different sequences of nanobody gene fragments were selected. The four nanobody fusion proteins were expressed and purified, respectively. The specificity and affinity of the four nanobodies were identified by ELISA. Our results showed that an immune phage display library against SARS-CoV-2 has been successfully constructed with a library capacity of which was 4.7 × 108 CFU. The four purified nanobodies showed specific high-affinity binding SARS-CoV-2 S-RBD. Among these, the antigen binding affinity of Nb61 was more comparable to that of commercial rabbit anti-SARS-CoV-2 S-RBD antibodies. In sum, our study has obtained four nanobody strains against SARS-CoV-2 S-RBD with significant affinity and specificity, therefore laying an essential foundation for further research as well as the applications of diagnostic and therapeutic tools of SARS-CoV-2.

Chimeric antigen receptor-based T-cell immunotherapy is a promising strategy for treatment of hematological malignant tumors; however, its efficacy towards solid cancer remains challenging. We therefore focused on developing nanobody-based CAR-T cells that treat the solid tumor. CD105 expression is upregulated on neoangiogenic endothelial and cancer cells. CD105 has been developed as a drug target. Here we show the generation of a CD105-specific nanobody, an anti-human CD105 CAR-T cells, by inserting the sequences for anti-CD105 nanobody-linked standard cassette genes into AAVS1 site using CRISPR/Cas9 technology. Co-culture with CD105+ target cells led to the activation of anti-CD105 CAR-T cells that displayed the typically activated cytotoxic T-cell characters, ability to proliferate, the production of pro-inflammatory cytokines, and the specific killing efficacy against CD105+ target cells in vitro. The in vivo treatment with anti-CD105 CAR-T cells significantly inhibited the growth of implanted CD105+ tumors, reduced tumor weight, and prolonged the survival time of tumor-bearing NOD/SCID mice. Nanobody-based CAR-T cells can therefore function as an antitumor agent in human tumor xenograft models. Our findings determined that the strategy of nanobody-based CAR-T cells engineered by CRISPR/Cas9 system has a certain potential to treat solid tumor through targeting CD105 antigen.

Adoptive cell-based immunotherapy typically utilizes cytotoxic T lymphocytes (CTLs), expanding these cells ex vivo. Such expansion is traditionally accomplished through the use of autologous APCs that are capable of interactions with T cells. However, incidental inhibitory program such as CTLA-4 pathway can impair T cell proliferation. We therefore designed a nanobody which is specific for CTLA-4 (CTLA-4 Nb 16), and we then used this molecule to assess its ability to disrupt CTLA-4 signaling and thereby overcome negative costimulation of T cells. With CTLA-4 Nb16 stimulation, dendritic cell/hepatocellular carcinoma fusion cells (DC/HepG2-FCs) enhanced autologous CD8+ T cell proliferation and production of IFN-γ in vitro, thereby leading to enhanced killing of tumor cells. Using this approach in the context of adoptive CD8+ immunotherapy led to a marked suppression of tumor growth in murine NOD/SCID hepatocarcinoma or breast cancer xenograft models. We also observed significantly increased tumor cell apoptosis, and corresponding increases in murine survival. These findings thus demonstrate that in response to nanobody stimulation, DC/tumor cells-FC-induced specific CTLs exhibit superior anti-tumor efficacy, making this a potentially valuable means of achieving better adoptive immunotherapy outcomes in cancer patients.

The purpose of this study was to investigate the significance of mismatch negativity (MMN) by comparing high-resolution electroencephalogram signals from tinnitus patients and healthy controls.

Two new compounds, macrolactin XY (1) and (5R, 9S, 10S)-5-(hydroxymethyl)-1,3,7-decatriene-9,10-diol (2), together with nine known compounds (3–11) were isolated from the marine Bacillus subtilis sp. 18 by the OSMAC strategy. These compounds were evaluated for antibacterial activity against six tested microorganisms. Compounds 1–5 and 7–10 showed varied antibacterial activity, with the minimum inhibitory concentration (MIC) ranging from 3 to 12 μg/mL. Macrolactin XY (1) was found to possess superior antibacterial activity, especially exhibiting significant effectiveness against Enterococcus faecalis. The antibacterial activity mechanism against E. faecalis was investigated. The mechanism may disrupt bacterial cell membrane integrity and permeability, and also inhibit the expression of genes associated with bacterial energy metabolism, as established by the experiments concerning cell membrane potential, SDS-PAGE electrophoresis, cell membrane integrity, and key gene expressions. This study offers valuable insights and serves as a theoretical foundation for the future development of macrolactins as antibacterial precursors. [ABSTRACT FROM AUTHOR]

In this work, the electromagnetic properties of Ni0.22Cu0.31Zn0.47Fe2O4 (NiCuZn) ferrites doped with 0.3 wt% Bi2O3 + xCuO flux (x = 0.2, 0.4, 0.6, and 0.8 wt%) were studied. Doping resulted in a reduction in the sintering temperature to 900 °C. The doped ferrites were synthesized via the solid-state method. XRD patterns revealed that the prepared ferrites had a cubic spinel structure; thus, a moderate addition of flux did not change the crystal structure. The SEM images, as well as the density and grain size distribution of the samples, showed that the NiCuZn ferrites had densified, homogenized, and contained fully grown grains for x = 0.6 wt%. The sample exhibited good soft magnetic properties, with μ′ reaching the maximum value of 245.4 for x = 0.6 wt% and ε′, Ms, and Hc reaching the maximum values of 23.1, 28.06 emu/g, and 45.86 Oe for x = 0.8 wt%, respectively. Furthermore, the ferrites exhibited good gyromagnetic properties, with 4πMs reaching the maximum value of 1744 Gauss for x = 0.8 wt% and ΔH reaching the minimum value of 228 Oe for x = 0.6 wt%. NiCuZn ferrites were successfully sintered at a lower temperature (900 °C) by adding Bi2O3–CuO flux through LTCC technology and exhibited good soft magnetic properties and gyromagnetic properties. We envisage that these ferrites could be used in multilayer devices. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the methylenetetrahydrofolate reductase (MTHFR) gene rs1801133 C>T polymorphisms and lung cancer susceptibility by pooling openly published data.