农药人工抗原合成的研究进展

综述了农药人工抗原合成、鉴定、偶联比测定和影响农药人工抗原质量的因素等方面研究进展。     

Identification of Surface Antigens That Define Human Pluripotent Stem Cell-Derived PRRX1+Limb-Bud-like Mesenchymal Cells

Stem cell-based therapies and experimental methods rely on efficient induction of human pluripotent stem cells (hPSCs). During limb development, the lateral plate mesoderm (LPM) produces limb-bud mesenchymal (LBM) cells that differentiate into osteochondroprogenitor cells and form cartilage tissues in the appendicular skeleton. Previously, we generated PRRX1-tdTomato reporter hPSCs to establish the protocol for inducing the hPSC-derived PRRX1⁺ LBM-like cells. However, surface antigens that assess the induction efficiency of hPSC-derived PRRX1⁺ LBM-like cells from LPM have not been identified. Here, we used PRRX1-tdTomato reporter hPSCs and found that high pluripotent cell density suppressed the expression of PRRX1 mRNA and tdTomato after LBM-like induction. RNA sequencing and flow cytometry suggested that PRRX1-tdTomato⁺ LBM-like cells are defined as CD44^high CD140B^high CD49f⁻. Importantly, other hPSC lines, including four human induced pluripotent stem cell lines (414C2, 1383D2, HPS1042, HPS1043) and two human embryonic stem cell lines (SEES4, SEES7), showed the same results. Thus, an appropriate cell density of hPSCs before differentiation is a prerequisite for inducing the CD44^high CD140B^high CD49f⁻ PRRX1⁺ LBM-like cells.     

Cell Therapy for Colorectal Cancer: The Promise of Chimeric Antigen Receptor (CAR)-T Cells

Colorectal cancer (CRC) is a global public health problem as it is the third most prevalent and the second most lethal cancer worldwide. Major efforts are underway to understand its molecular pathways as well as to define the tumour-associated antigens (TAAs) and tumour-specific antigens (TSAs) or neoantigens, in order to develop an effective treatment. Cell therapies are currently gaining importance, and more specifically chimeric antigen receptor (CAR)-T cell therapy, in which genetically modified T cells are redirected against the tumour antigen of interest. This immunotherapy has emerged as one of the most promising advances in cancer treatment, having successfully demonstrated its efficacy in haematological malignancies. However, in solid tumours, such as colon cancer, it is proving difficult to achieve the same results due to the shortage of TSAs, on-target off-tumour effects, low CAR-T cell infiltration and the immunosuppressive microenvironment. To address these challenges in CRC, new approaches are proposed, including combined therapies, the regional administration of CAR-T cells and more complex CAR structures, among others. This review comprehensively summarises the current landscape of CAR-T cell therapy in CRC from the potential tumour targets to the preclinical studies and clinical trials, as well as the limitations and future perspectives of this novel antitumour strategy.     

基于人工免疫模型的在线手写签名识别方法

采集能表征签名者潜在手写习惯的签名特征,利用人工免疫模型的自学习和自适应实现在较少训练样本的条件下获得具有更高区分度的手写签名模板.实验结果表明,文中方法识别具有良好的训练效果,能获得较好的验证率和鉴别率.     

罗丹明123人工抗原的合成及抗体的酶联免疫检测

为建立罗丹明B(rhodamine B)的免疫分析方法,采用戊二醛法,将半抗原罗丹明123与载体牛血清白蛋白(BSA)及卵清蛋白(OVA)偶联制备免疫抗原R123-B S A和包被抗原R123-OVA。经动物免疫实验证实人工抗原合成,并制备抗罗丹明123的多克隆抗体,此抗体同时能够检测食品中的罗丹明B,且最低检测限为0.001ng/mL。     

多效唑人工抗原的合成与鉴定

为合成新的、有效的多效唑人工抗原,采用琥珀酸酐法对多效唑小分子进行结构修饰,以获得含羧基的多效唑半抗原。将纯化后的半抗原分别与牛血清白蛋白和卵清蛋白经N-羟基琥珀酰亚胺活泼酯法偶联制备免疫原和包被原。采用质谱、红外光谱、核磁共振氢谱对多效唑半抗原的结构进行鉴定;采用紫外光谱及高性能基质辅助激光解吸电离-飞行时间质谱对偶联物的结构进行鉴定。结果显示成功合成出多效唑人工抗原,为其抗体的制备和免疫学方法的构建奠定了前期研究基础。     

Optimization of conditions for single-step purification of recombinant hepatitis B surface antigen produced in Pichia pastoris using ion exchange chromatography

ABSTRACT

The adsorption and release of rHBsAg extracted from the final dosage form on various ion exchange resins and under different pH conditions were investigated after its peptide map and isoelectric point (PI) determination. Efficient antigen adsorption to the anion exchange resins occurred when the pH value of the protein buffer was adjusted to 5.0. In purification of rHBsAg derived from the yeast crude extract using Q Sepharose FF column, with adjusting the pH value of the crude extract to 5.0 (i.e., near to the target protein PI) and using 2M NaCl, rHBsAg with high purity (up to >95%) was obtained.

Abbreviations: rHBsAg, recombinant hepatitis B surface antigen; Alhydrogel, aluminum hydroxide; IEF, isoelectric focusing; PI, isoelectric point; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; RP-HPLC, reversed-phase high-performance liquid chromatography; SE-HPLC, size-exclusion high-performance liquid chromatography; PBS, phosphate-buffered saline     

Mannose Receptor-Mediated Carbon Nanotubes as an Antigen Delivery System to Enhance Immune Response Both In Vitro and In Vivo

Carbon nanotubes (CNTs) are carbon allotropes consisting of one, two, or more concentric rolled graphene layers. These can intrinsically regulate immunity by activating the innate immune system. Mannose receptors (MR), a subgroup of the C-type lectin superfamily, are abundantly expressed on macrophages and dendritic cells. These play a crucial role in identifying pathogens, presenting antigens, and maintaining internal environmental stability. Utilizing the specific recognition between mannose and antigen-presenting cells (APC) surface mannose receptors, the antigen-carrying capacity of mannose-modified CNTs can be improved. Accordingly, here, we synthesized the mannose-modified carbon nanotubes (M-MWCNT) and evaluated them as an antigen delivery system through a series of in vitro and in vivo experiments. In vitro, M-MWCNT carrying large amounts of OVA were rapidly phagocytized by macrophages and promoted macrophage proliferation to facilitate cytokines (IL-1β, IL-6) secretion. In vivo, in mice, M-MWCNT induced the maturation of dendritic cells and increased the levels of antigen-specific antibodies (IgG, IgG1, IgG2a, IgG2b), and cytokines (IFN-γ, IL-6). Taken together, M-MWCNT could induce both humoral and cellular immune responses and thereby can be utilized as an efficient antigen-targeted delivery system.     

草甘膦单克隆抗体的制备及酶联免疫分析方法的建立

目的 制备出草甘膦(glyphosate,GLY)单克隆抗体,建立间接竞争酶联免疫吸附法(enzyme linked immunosorbent assay, ELISA)快速检测茶叶中GLY的方法。方法 首先合成GLY完全抗原(包被原和免疫原),通过免疫小鼠成功制备出GLY单克隆抗体。根据ELISA的检测流程,采用棋盘法确定最佳包被抗原和抗体的稀释倍数,确定最佳包被的温度和时间,并确定最佳加入一抗、二抗后反应时间,建立检测方法并对其性能进行评价。结果 GLY包被抗原和抗体的稀释倍数为1:2000,包被温度为37℃、包被时间为90 min,加入一抗、二抗后反应时间为60min。该方法的线性方程为Y=-0.2353X+0.6539(r²=0.9871),半抑制浓度(50%inhibiting concentration, IC₅₀)为4.508 ng/mL,检出限为1.18 ng/mL。变异系数均在10%以下,与异菌脲、多菌灵、三唑磷、甲基对硫磷、噻菌灵这5种标准品的交叉反应率均低于0.03%,在茶叶中加标回收率为90.86%～110.35%,...     

ERAP2 Inhibition Induces Cell-Surface Presentation by MOLT-4 Leukemia Cancer Cells of Many Novel and Potentially Antigenic Peptides

Recent studies have linked the activity of ER aminopeptidase 2 (ERAP2) to increased efficacy of immune-checkpoint inhibitor cancer immunotherapy, suggesting that pharmacological inhibition of ERAP2 could have important therapeutic implications. To explore the effects of ERAP2 inhibition on the immunopeptidome of cancer cells, we treated MOLT-4 T lymphoblast leukemia cells with a recently developed selective ERAP2 inhibitor, isolated Major Histocompatibility class I molecules (MHCI), and sequenced bound peptides by liquid chromatography tandem mass spectrometry. Inhibitor treatment induced significant shifts on the immunopeptidome so that more than 20% of detected peptides were either novel or significantly upregulated. Most of the inhibitor-induced peptides were 9mers and had sequence motifs and predicted affinity consistent with being optimal ligands for at least one of the MHCI alleles carried by MOLT-4 cells. Such inhibitor-induced peptides could serve as triggers for novel cytotoxic responses against cancer cells and synergize with the therapeutic effect of immune-checkpoint inhibitors.