It is well known that Astragalus polysaccharide (APS) exerts potent antitumor effects by enhancing T cell cytotoxicity via the PD-1/PD-L1 axis. However, whether APS can also modulate T cell activity via alternative checkpoint molecules remains unclear. Here, we addressed this question using complementary in vitro and in vivo approaches. In vitro, APS reduced the Tim-3 + cell population among human PBMCs. Further analysis revealed that APS specifically affected only the proportion of Tim-3 +CD8 + T cells. Along with the decreased proportion of Tim-3 + cells, CD8 + T cell immune activity was enhanced, as shown by increased expression of the early activation molecule CD69, increased secretion of GZMB, and enhanced capacity to kill human lung cancer cells. The results of transcriptome sequencing suggested that the APS-induced downregulation of Tim-3 might be related to the regulation of the transcription factor RORB. Experiments in an in vivo B16-F10 melanoma model revealed that APS enhanced T cell function by reducing the number of tumor-infiltrating Tim-3 + T cells, consequently suppressing tumor cell proliferation in mice. Collectively, our findings demonstrate that APS reduces the Tim-3 +CD8 + T cell population among PBMCs and enhances T cell cytotoxicity, providing a novel theoretical foundation for explaining the mechanism underlying APS immunomodulation.
Severe combined immunodeficient (SCID) mice serve as a critical model for human xenotransplantation studies, yet they often suffer from low engraftment rates and susceptibility to graft-versus-host disease (GVHD). Moreover, certain SCID strains demonstrate ‘immune leakage’, underscoring the need for novel model development. Here, we introduce an SCID mouse model with a targeted disruption of the dclre1c gene, encoding Artemis, which is essential for V(D)J recombination and DNA repair during T cell receptor (TCR) and B cell receptor (BCR) assembly. Artemis deficiency precipitates a profound immunodeficiency syndrome, marked by radiosensitivity and compromised T and B lymphocyte functionality. Utilizing CRISPR/Cas9-mediated gene editing, we generated dclre1c-deficient mice with an NOD genetic background. These mice exhibited a radiosensitive SCID phenotype, with pronounced DNA damage and defective thymic, splenic and lymph node development, culminating in reduced T and B lymphocyte populations. Notably, both cell lines and patient-derived tumor xenografts were successfully engrafted into these mice. Furthermore, the human immune system was effectively rebuilt following peripheral blood mononuclear cells (PBMCs) transplantation. The dclre1c-knockout NOD mice described herein represent a promising addition to the armamentarium of models for xenotransplantation, offering a valuable platform for advancing human immunobiological research.
The mouse genome has a high degree of homology with the human genome, and its physiological, biochemical, and developmental regulation mechanisms are similar to those of humans; therefore, mice are widely used as experimental animals. However, it is undeniable that interspecies differences between humans and mice can lead to experimental errors. The differences in the immune system have become an important factor limiting current immunological research. The application of immunodeficient mice provides a possible solution to these problems. By transplanting human immune cells or tissues, such as peripheral blood mononuclear cells or hematopoietic stem cells, into immunodeficient mice, a human immune system can be reconstituted in the mouse body, and the engrafted immune cells can elicit human-specific immune responses. Researchers have been actively exploring the development and differentiation conditions of host recipient animals and grafts in order to achieve better immune reconstitution. Through genetic engineering methods, immunodeficient mice can be further modified to provide a favorable developmental and differentiation microenvironment for the grafts. From initially only being able to reconstruct single T lymphocyte lineages, it is now possible to reconstruct lymphoid and myeloid cells, providing important research tools for immunology-related studies. In this review, we compare the differences in immune systems of humans and mice, describe the development history of human immune reconstitution from the perspectives of immunodeficient mice and grafts, and discuss the latest advances in enhancing the efficiency of human immune cell reconstitution, aiming to provide important references for immunological related researches.
Alcohol-associated liver disease (ALD) is induced by chronic excessive alcohol consumption resulting in the clinical manifestations of steatosis, inflammation, and cirrhosis. MicroRNA-29b (miR-29b) is mainly expressed in hepatic nonparenchymal cells, and its expression level varies in different diseases. In this study, we aimed to determine the role of miR-29b in a mouse model of alcohol-associated liver disease. Wild-type (WT) and miR-29b knockout (miR-29b(-/-)) mice were fed a Lieber-DeCarli liquid diet containing 5% alcohol for 10 days, followed by gavage of a single dose of ethanol (5 g/kg body weight). Histology, immunoblotting, and biochemical analyses were then conducted for comparison. miR-29b expression was decreased in the livers of chronic-plus-binge ethanol-fed mice. Further analysis revealed that alcohol exposure exacerbated hepatic injury by significantly increasing serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, with decreased survival rates for miR-29b(-/-) mice. Results from the luciferase assay indicated that miR-29b negatively regulated the signal transducer and activator of transcription 3 (STAT3). Depletion of miR-29b led to an increase in STAT3 and more noticeable inflammation in the liver, whereas overexpression of miR-29b downregulated STAT3 and proinflammatory cytokine expression in primary mouse peritoneal macrophages. Taken together, these results demonstrate a novel association between miR-29b and ALD. miR-29b plays a hepatoprotective role in alcohol-induced inflammation and liver injury by targeting STAT3. (c) 2021 Elsevier Inc. All rights reserved.
Non-small cell lung cancer (NSCLC) is a highly malignant tumor, with a significant mortality and morbidity. With the development of tumor immunotherapy, chimeric antigen receptor T cells (CART) gets increasingly attention and achieves prominent contributions in the treatment of hematologic malignancies. However, CART therapy for NSCLC proceeds slowly and further researches need to be investigated. In our study, we performed bioinformatics analysis to evaluate the significant role of CD147 in NSCLC. The expression level of CD147 was detected in human NSCLC cell lines and NSCLC tissues. Meanwhile, CD147-CART was constructed and identified. Cell cytotoxicity and cytokine secretion were performed to evaluate the efficacy of CD147-CART. We also constructed cell-derived xenograft (CDX) model and patient-derived xenograft (PDX) model, which was used to further investigate the safety and efficacy of CD147-CART in vivo. Our observations show that CD147 is a specific tumor antigen of NSCLC and plays an essential role in NSCLC progression, which can be used as a target for CART therapy in NSCLC. CD147-CART cells exhibit robust cytotoxicity and cytokine production in vitro, suggesting a strong anti-tumor activity against NSCLC tumor cells. Importantly, CD147-CART cells have strong anti-tumor activity against NSCLC cells in vivo in both CDX and PDX models and no adverse side effects. Our findings show that CD147-CART immunotherapy for NSCLC is safe and effective, which is an ideal and promising medical patch for treating NSCLC.
Autophagy is a conserved self-degradation system closely related to cancer progression. Small molecule inhibitors of autophagy have proven to be efficient tools in cancer therapy and are in high demand. Here we report the discovery of two compounds (LZ02/01) capable of suppressing cancer cell proliferation via inhibiting autophagy flux and promoting apoptosis. Potential autophagy inhibitors were selected based on the pharmacophore model derived from the structures of known autophagy inhibitors. LZ02/01-mediated autophagy flux disruption and apoptosis promotion in breast and hepatocellular carcinoma cells (MCF-7 and Hep3B) were examined using a combination of molecular methods in vitro and in vivo. The synergistic tumor-suppressing effects of LZ02 and chloroquine were validated by adopting a xenograft mice model of human breast cancer. Two potential inhibitors (LZ02/01) targeting an autophagy pathway were discovered from the Enamine database. In both MCF-7 and Hep3B cells, LZ02 and LZ01 had the effect of causing the co-occurrence of autophagic flux inhibition and apoptosis induction, robustly suppressing the growth, proliferation, and cell cycle progression. Further tests revealed that FoxO3a and its downstream target genes regulating autophagy, apoptosis, and cell cycle progression were activated and overexpressed, suggesting such effects of LZ02/01 on autophagy and apoptosis were associated with the activation and overexpression of FoxO3a. In addition, LZ02/01-mediated apoptosis is not independent; it was verified to be promoted by autophagic flux inhibition. Meanwhile, synergistic effects on tumor growth reduction were detected in the xenograft mice model of human breast cancer simultaneously treated with LZ02 and chloroquine. Our findings suggest that LZ01 and LZ02 are potent in suppressing cancer cell proliferation and tumor growth through autophagic flux inhibition and apoptosis promotion. The synergistic anti-cancer effects of LZ02 with chloroquine may provide a rational basis for prospective cancer therapy. KEY MESSAGES: A ligand-based pharmacophore model of high quality is constructed to query hits and two novel scaffold lead compounds LZ01/02 were identified by high-throughput virtual screening. LZ01/02 works to inhibit autophagic flux by attenuating lysosome function. LZ01/02 induces apoptosis through autophagic flux inhibition and apoptosis is the main mechanism to inhibit MCF-7 and Hep3B cancer cell proliferation. The synergistic antitumor growth effects of LZ02 and chloroquine are verified in human xenograft model.
Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas)9 is a novel and convenient gene editing system that can be used to construct genetically modified animals. Recombination activating gene 2 (Rag2) is a core component that is involved in the initiation of V(D)J recombination during T- and B-cells maturation. Separately, the interleukin-2 receptor gamma chain gene (IL2rg) encoded the protein-regulated activity of natural killer (NK) cells and shared common receptors of some cytokines. Rag2 and IL2rg mutations cause immune system disorders associated with T-, B-, and NK cell function and some cytokine activities. In the present study, 2 single-guide RNAs (sgRNAs) targeted on Rag2 and IL2rg genes were microinjected into the zygotes of BALB/c mice with Cas9 messenger RNA (mRNA) to create Rag2/IL2rg-/- double knockout mice, and the biological characteristics of the mutated mice were subsequently analyzed. The results showed that CRISPR/Cas9-induced indel mutation displaced the frameshift of Rag2 and IL2rg genes, resulting in a decrease in the number of T-, B-, and NK cells and the destruction of immune-related tissues like the thymus and spleen. Mycobacterium tuberculosis 85B antigen could not induce cellular and humoral immune response in mice. However, this aberrant immune activity compromised the growth of several tumor heterogenous grafts in the mutated mice, including orthotopic and subcutaneous transplantation tumors. Thus, Rag2/IL2rg-/- knockout mice possessed features of severe combined immunodeficiency (SCID), which is an ideal model for human xenograft.
目的 运用CRISR/Cas9技术敲除小鼠基因组中Bmp9基因片段,构建Bmp9基因敲除小鼠.方法根据Bmp9基因的外显子序列,设计一段sgRNA并合成.sgRNA体外转录后和Cas9 mRNA混合后显微注射受精卵细胞,注射后的受精卵细胞移植至受体动物获得子代小鼠.提取子代小鼠基因组DNA测序鉴定其基因型.基因型鉴定正确的小鼠与野生型交配后筛选纯合子小鼠.同时取纯合子小鼠心脏、肝、脾、肺、肾,匀浆后提取总RNA和总蛋白,通过qPCR、WB和免疫组化检测BMP9在各组织中的表达.结果设计并合成20 bp的sgRNA并进行体外转录,显微注射并回植后得到基因突变小鼠,连续交配后得F2代纯合子.测序结果显示,突变小鼠存在两种基因型,一种为5 bp缺失突变,另一种为13 bp缺失并伴有1 bp插入突变.与野生型C57BL/6相比,qPCR、WB和免疫组化结果均表明基因敲除小鼠肝中BMP9表达显著降低.结论利用CRISPR/Cas9技术成功构建出了BMP9基因敲除小鼠.
目的 利用双重sgRNAs构建miR-223全基因敲除小鼠.方法 针对miR-223基因设计双重sgRNAs,将体外转录的sgRNAs和Cas9 mRNA共同显微注射入C57BL/6小鼠受精卵细胞.小鼠出生后取其基因组DNA进行PCR扩增和测序以鉴定基因型,同时取小鼠肝脏研磨后提取总RNA,通过real-time PCR分析miR-223在肝脏中的表达.结果 设计了miR-223基因双重sgRNAs并对其进行了体外转录,纯化后显微注射小鼠受精卵细胞获得miR-223基因突变小鼠.测序结果表明突变小鼠有3种基因型,一种为6 bp的缺失突变,但未对miR-223序列产生影响;另外两种为162 bp和168 bp的缺失突变,完全删除miR-223前体和成熟区序列.与野生型相比,这两种小鼠肝组织中几乎不能检测到miR-223的表达.结论 设计双重sgRNAs并应用CRISPR/Cas9技术成功构建miR-223全基因敲除小鼠.
目的 观察Hedgehog通路抑制剂GANT61对人乳腺癌MCF-7细胞的抑制作用.方法 GANT61作用MCF-7细胞后,通过流式细胞术检测细胞死亡;提取处理细胞总RNA和蛋白.分别采用Real-time PCR和Westem blot检测Hedgehog通路SHH、Gli1、Gli2及自噬标志物LC3-Ⅱ表达;处理细胞固定后通过电子显微镜观察GANT61诱导的自噬体形态;自噬抑制剂3-MA处理细胞或自噬相关基因atg5 siRNA转染细胞后再用GANT61作用,流式细胞术检测细胞死亡数量.结果 GANT61能明显诱导MCF-7死亡,降低Hedgeho g通路SHH、Gli1、Gli2表达水平,提高LC3-Ⅱ蛋白表达,并可诱导MCF-7细胞产生自噬体.3-MA及atg5 siRNA可减弱GANT61诱导的细胞死亡.结论 GANT61通过诱导自噬性细胞死亡机制发挥抗乳腺癌细胞活性.
本文从小鼠的超数排卵、采集胚胎、原核受精卵显微注射、胚胎移植、基因型鉴定等多个环节,详细阐述制备基因工程小鼠的技术操作要领;通过实施辅助生殖技术IVF(体外受精)、精子和胚胎的冷冻、复苏技术实现了基因工程小鼠的保种和育种,涉及相关技术的要点改进和操作体会,成功建成了基因工程小鼠的制备和保种、育种平台,提供了良好的技术服务.
Objective To construct miRNA-29b1 gene knockout mice based on CRISPR/Cas9 technology. Methods To design and synthesize sgRNA according to the miRNA-29b1 sequence in Genbank .sgRNA and Cas9 were transcribed to RNA in vitro, these RNA were then microinjected into zygotes of C 57BL/6 mice.After mouse birth, the genome DNA was extracted and sequenced to identify its genotype; meanwhile , real-time PCR was used to assay the expression of miRNA-29b1 in the heart, liver, spleen, lung and kidney of mutated mice .Result A 20 bp sgRNA targeted on miRNA-29b1 was synthesized and transcribed to RNA with Cas 9.After microinjection, miRNA-29b1 gene-mutated mice were obtained.The sequencing results showed that there were two types of genotype for the mutated mice , one was 10 bp deletion, and another was 23 bp deletion accompanied with a 3 bp insertion.Compared with the wild-type mice, the expression of miRNA-29b1 in the heart, liver, spleen, lung and kidney was reduced significantly .Conclusions miRNA-29b1 gene knockout mice are constructed successfully by using CRISPR /Cas9 technology.