Effects of copper on gill function of juvenile oriental river prawn (Macrobrachium nipponense): Stress and toxic mechanism.

As an important trace element and the accessory factor of many enzymatic processes, heavy metal copper is essential to aquatic animals. The toxic mechanism of copper on gill function of M. nipponense was clarified for the first time in terms of histopathological analysis, physiology, biochemistry and the expression of important genes. The results obtained by present in present research showed that heavy metal copper could affect normal respiratory and metabolic activities in M. nipponense. Copper stress could cause damage to the mitochondrial membrane of gill cells in M. nipponense, and the activity of mitochondrial respiratory chain complex could be inhibited by copper. Copper could affect normal electron transport and mitochondrial oxidative phosphorylation, resulting in the inhibition of energy production. High concentrations of copper could disrupt intracellular ion balance and induce cytotoxicity. The oxidative stress could be induced by copper, leading to excessive ROS. Copper could reduce the mitochondrial membrane potential, lead to the leakage of apoptotic factors, and induce apoptosis. Copper could damage structure of gill, affect normal respiration of gill. This study provided fundamental data for exploring impacts of copper on gill function in aquatic organisms and potential mechanisms of copper toxicity.

Comparative transcriptome analysis of gonads in male and female Pseudobagrus ussuriensis (Bagridae, Siluriformes).

As an important aquaculture fish in the Heilongjiang River Basin, Pseudobagrus ussuriensis has high economic value, and all-male culture is beneficial to the economic development of this fish. In this study, the transcriptomes of gonads in males and females were analyzed, and some genes related to gonad development were found. A total of 82,931 unigenes were found (average length 1504 bp, N50 1829 bp). In addition, 4689 differentially expressed genes (DEGs; including 1424 genes upregulated and 3265 genes downregulated in males) were identified. Some genes associated with testis development (such as Dmrt1 and Ropn1l) were significantly upregulated in males, while genes related to ovary development (such as Wnt2, PLC, Cyp19a, ZP3) were significantly downregulated in males, demonstrating that these genes have a crucial influence on gonad development in P. ussuriensis. Some signaling pathways related to gonad development were found, such as the Wnt pathway and oocyte meiosis. The results of RNA-seq obtained in this study provide theoretical data for elucidating the potential mechanism of gonad development of P. ussuriensis and reliable genomic data for the establishment of mono-sex breeding of P. ussuriensis.

Significantly increased anti-tumor activity of carcinoembryonic antigen-specific chimeric antigen receptor T cells in combination with recombinant human IL-12.

BACKGROUND AIMS: Chimeric antigen receptor T cells (CAR-T cells) have been successfully used in treatments of hematological tumors, however, their anti-tumor activity in solid tumor treatments was limited. As IL-12 increases T-cell immune functions, we designed carcinoembryonic antigen (CEA) specific CAR-T (CEA-CAR-T) cells and, for the first time, used them in combination with recombinant human IL-12 (rhIL-12) to treat several types of solid tumors. METHODS: In vitro anti-tumor activity of CEA-CAR-T cells in combination with rhIL-12 was confirmed by evaluation of CEA-CAR-T cell activation, proliferation, and cytotoxicity after co-incubation with CEA-positive or CEA-negative human tumor cells. In vivo anti-tumor activity of CEA-CAR-T cells in combination with rhIL-12 was confirmed in a xenograft model in nude mice for treatments of several types of solid tumors. RESULTS: In vitro experiments confirmed that rhIL-12 significantly increased the activation, proliferation, and cytotoxicity of CEA-CAR-T cells. Similarly, in vivo experiments found that CEA-CAR-T cells in combination with rhIL-12 had significantly enhanced anti-tumor activity than CEA-CAR-T cells in growth inhibition of newly colonized colorectal cancer cell HT-29, pancreatic cancer cell AsPC-1, and gastric cancer cell MGC803. CONCLUSIONS: These works confirmed that simultaneous use of cytokines, for example, rhIL-12, can increase the anti-tumor activity of CAR-T cells, especially for treatments of several types of solid tumors.

Recombination of a dual-CAR-modified T lymphocyte to accurately eliminate pancreatic malignancy.

BACKGROUND: The therapeutic application of T cells endowing with chimeric antigen receptors (CARs) is faced with "on-target, off-tumor" toxicity against solid tumors, particularly in the treatment of the pancreatic cancer. To our best knowledge, the pancreatic cancer cell line AsPC-1 often highly expressed some distinct tumor-associated antigens, such as carcino-embryonic antigen (CEA) and mesothelin (MSLN). Therefore, in this research, we have characterized dual-receptor CAR-modified T cells (dCAR-T) that exert effective and safe cytotoxicity against AsPC-1 cells. METHODS: Based on the dual signaling pathway of wild T cells, we designed a novel dCAR diagram specific for CEA and MSLN, which achieved comparable activity relative to that of conventional CAR-T cells (CEA-CAR T or MSLN-CAR T). In this dCAR, a tandem construct containing two physically separate structures, CEA-CD3ζ and MSLN-4/1BB signaling domains were effectively controlled with tumor antigens CEA and MSLN, respectively. Finally, the activity of dCAR-T cells has been verified via in vitro and in vivo experiments. RESULTS: In the presence of cognate tumor cells (AsPC-1) expressing both CEA and MSLN, dCAR-T cells exerted high anti-tumor activity relative to that of other single-receptor CAR-T cells bearing only one signaling pathway (e.g., Cζ-CAR and MBB-CAR). In a xenograft model, dCAR-T cells significantly inhibited the growth of AsPC-1 cells yet no effect on the growth of non-cognate tumor cells. Furthermore, the released cytokines and T cell persistence in mice were comparable with that of conventional CAR-T cells, obtaining specific and controllable cytotoxicity. CONCLUSIONS: A novel type of CAR-T cells, termed dCAR-T, was designed with specific activities, that is, significant cytotoxicity for two antigen-positive tumor cells yet no cytotoxicity for single antigen-positive tumor cells. Dual-targeted CAR-T cells can be precisely localized at the tumor site and can exert high cytotoxicity against tumor cells, alleviating "on-target, off-tumor" toxicity and enabling accurate application of CAR-T cell therapy.

Accurate control of dual-receptor-engineered T cell activity through a bifunctional anti-angiogenic peptide.

BACKGROUND: Chimeric antigen receptors (CARs) presented on T cell surfaces enable redirection of T cell specificity, which has enormous promise in antitumor therapy. However, excessive activity and poor control over such engineered T cells cause significant safety challenges, such as cytokine release syndrome and organ toxicities. To enhance the specificity and controllable activity of CAR-T cells, we report a novel switchable dual-receptor CAR-engineered T (sdCAR-T) cell and a new switch molecule of FITC-HM-3 bifunctional molecule (FHBM) in this study. METHODS: We designed a fusion molecule comprising FITC and HM-3. HM-3, an antitumor peptide including an Arg-Gly-Asp sequence, can specifically target integrin αvß3 that is presented on some tumor cells. Moreover, to improve the specificity of CAR-T cells, we also generated the sdCAR-T cell line against cognate tumor cells expressing human mesothelin (MSLN) and integrin αvß3. Finally, the activity of sdCAR-T cell and FHBM is verified via in vitro and in vivo experiments. RESULTS: In the presence of FHBM, the designed sdCAR-T cells exerted high activity including activation and proliferation and had specific cytotoxicity in a time- and dose-dependent manner in vitro. Furthermore, using a combination of FHBM in nude mice, sdCAR-T cells significantly inhibited the growth of MSLN+ K562 cells and released lower levels of the cytokines (e.g., interleukin-2, interferon γ, interleukin-6, and tumor necrosis factor α) relative to conventional CAR-T cells, obtaining specific, controllable, and enhanced cytotoxicity. CONCLUSIONS: Our data indicate that FHBM can accurately control timing and dose of injected CAR-T cells, and sdCAR-T cells exert significant antitumor activity while releasing lower levels of cytokines for the cognate tumor cells expressing both MSLN and integrin αvß3. Therefore, combination therapies using sdCAR-T cells and the switch molecule FHBM have significant potential to treat malignancies.

Prospects for chimeric antigen receptor-modified T cell therapy for solid tumors.

The potential for adoptive cell immunotherapy as a treatment against cancers has been demonstrated by the remarkable response in some patients with hematological malignancies using autologous T cells endowed with chimeric antigen receptors (CARs) specific for CD19. Clinical efficacy of CAR-T cell therapy for the treatment of solid tumors, however, is rare due to physical and biochemical factors. This review focuses on different aspects of multiple mechanisms of immunosuppression in solid tumors. We characterize the current state of CAR-modified T cell therapy and summarize the various strategies to combat the immunosuppressive microenvironment of solid tumors, with the aim of promoting T cell cytotoxicity and enhancing tumor cell eradication.

Predicting miRNA's target from primary structure by the nearest neighbor algorithm.

We used a machine learning method, the nearest neighbor algorithm (NNA), to learn the relationship between miRNAs and their target proteins, generating a predictor which can then judge whether a new miRNA-target pair is true or not. We acquired 198 positive (true) miRNA-target pairs from Tarbase and the literature, and generated 4,888 negative (false) pairs through random combination. A 0/1 system and the frequencies of single nucleotides and di-nucleotides were used to encode miRNAs into vectors while various physicochemical parameters were used to encode the targets. The NNA was then applied, learning from these data to produce a predictor. We implemented minimum redundancy maximum relevance (mRMR) and properties forward selection (PFS) to reduce the redundancy of our encoding system, obtaining 91 most efficient properties. Finally, via the Jackknife cross-validation test, we got a positive accuracy of 69.2% and an overall accuracy of 96.0% with all the 253 properties. Besides, we got a positive accuracy of 83.8% and an overall accuracy of 97.2% with the 91 most efficient properties. A web-server for predictions is also made available at http://app3.biosino.org:8080/miRTP/index.jsp.