Rationale: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are a standard therapy for non-small cell lung cancer (NSCLC). Despite their clinical efficacy, dose-limiting systemic toxicity and the eventual development of acquired resistance limit their long-term benefit. Therefore, innovative drug delivery strategies are highly demanded to optimize the therapeutic window, minimizing toxicity of EGFR-TKIs at lower doses without compromising their efficacy. Methods: We developed a red blood cell (RBC)-based biomimetic platform for the systemic delivery of EGFR-TKIs. Osimertinib-loaded poly(lactic-co-glycolic acid) nanoparticles were camouflaged with a biotinylated RBC membrane (Osi-RNPs). They were then conjugated to the surface of RBCs via high-affinity biotin-streptavidin interactions to form a stable construct (Osi-RNP-SA-RBC). The physicochemical characteristics, cellular uptake, and in vitro antitumor activity of Osi-RNPs were characterized. We further assessed the pharmacokinetics, biodistribution, therapeutic efficacy, and safety profile of Osi-RNP-SA-RBC in subcutaneous and orthotopic NSCLC mouse models. Results: The Osi-RNP-SA-RBC platform demonstrated stable attachment, favorable hematocompatibility and excellent biosafety. Compared to the Osi-RNP-RBC (nonspecific adsorption), Osi-RNP-SA-RBC presented prolonged blood circulation (1.6-fold) and enhanced tumor accumulation (2.2-fold). Upon intravenous injection of Osi-RNP-SA-RBC at a reduced dose and frequency, superior tumor suppression was observed in both subcutaneous (16.8-fold increase) and orthotopic (4.2-fold increase) NSCLC mouse models compared to the free osimertinib at same administration dosage. Conclusion: This study demonstrates the potential of RBC-conjugated biomimetic nanomedicine as a promising strategy for enhancing the treatment efficiency of EGFR-TKI against NSCLC in vivo.
Cholera is a severe infectious disease caused by the Gram-negative bacterium Vibrio cholerae after colonization in the intestinal tract. Cholera toxin (CT), a key exotoxin protein, primarily causes acute secretory diarrhea and life-threatening complications in infected patients. Traditional approaches remain insufficient for effectively treating cholera, underscoring the need for innovative countermeasures to eliminate CT-caused symptoms. Here, we report a glycan-modified cellular nanosponge for the enhanced treatment of CT-induced secretory diarrhea. Specifically, intestinal epithelial cell membrane-camouflaged nanosponges are functionalized with a glycan receptor to promote their capability for CT neutralization, thereby competitively inhibiting CT entry into host cells. Moreover, an inhibitor is encapsulated into the cellular nanosponge to synergistically improve the therapeutic effect of diarrhea by blocking the excessive chloride ion efflux from the cystic fibrosis transmembrane conductance regulator (a crucial anion channel) on the membrane of CT-intoxicated epithelial cells. Upon oral administration, the biomimetic nanomedicine effectively eliminates CT-induced secretory diarrhea and intestinal injuries in mice. Overall, this study highlights the potential of glycan-modified cellular nanosponges as promising and broad-spectrum therapeutic agents against secretory diarrhea caused by bacterial exotoxins.
Triple-negative breast cancer (TNBC) is the most aggressive and lethal subtype of breast cancer among women. Chemotherapy acts as the standard regimen for TNBC treatment but suffers from limited drug accumulation in tumor regions and undesired side effects. Herein, we developed a synergistic strategy by combining a red blood cell (RBC) membrane-liposome hybrid nanovesicle with short-term fasting (STF) for improved chemotherapy of TNBC. The biomimetic nanovesicles exhibited reduced phagocytosis by macrophages while displaying a significant increase in tumor cell uptake through caveolae/raft-mediated endocytosis under nutrient-deprivation conditions. Importantly, drug-loaded nanovesicles and STF treatment synergistically increased the cytotoxicity of tumor cells by inhibiting their cell cycles and aerobic glycolysis as well as amplifying the reactive oxygen species (ROS) and autophagosomes generation. In the STF-treated mice, biomimetic nanovesicles greatly improved the antitumor efficacy at a lower drug dosage and inhibited the undesired metastasis of TNBC. Overall, we demonstrated that biomimetic nanovesicles synergizing with STF therapy serve as a promising therapeutic strategy for enhanced chemotherapy of malignant TNBC.
Vaccines provide a powerful tool to modulate the immune system for human disease prevention and treatment. Classical vaccines mainly initiate immune responses in the lymph nodes (LNs) after subcutaneous injection. However, some vaccines suffer from inefficient delivery of antigens to LNs, undesired inflammation, and slow immune induction when encountering the rapid proliferation of tumors. Alternatively, the spleen, as the largest secondary lymphoid organ with a high density of antigen-presenting cells (APCs) and lymphocytes, acts as an emerging target organ for vaccinations in the body. Upon intravenous administration, the rationally designed spleen-targeting nanovaccines can be internalized by the APCs in the spleen to induce selective antigen presentation to T and B cells in their specific sub-regions, thereby rapidly boosting durable cellular and humoral immunity. Herein, the recent advances of spleen-targeting nanovaccines for immunotherapy based on the anatomical architectures and functional zones of the spleen, as well as their limitations and perspectives for clinical applications are systematically summarized. The aim is to emphasize the design of innovative nanovaccines for enhanced immunotherapy of intractable diseases in the future.
Background: Lung adenocarcinoma (LUAD) shows intratumoral heterogeneity, a highly complex phenomenon that known to be a challenge during cancer therapy. Considering the key role of monocytic myeloid-derived suppressor cells (M-MDSCs) in the tumor microenvironment (TME), we aimed to build a prognostic risk model using M-MDSCs-related genes.Methods: M-MDSCs-related genes were extracted from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Utilized univariate survival analysis and random forest algorithm to screen candidate genes. A least absolute shrinkage and selection operator (LASSO) Cox regression analysis was selected to build the risk model. Patients were scored and classified into high- and low-risk groups based on the median risk scores. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis along with R packages "estimate " and "ssGSEA " were performed to reveal the mechanism of risk difference. Prognostic biomarkers and tumor mutation burden (TMB) were combined to predict the prognosis. Nomogram was carried out to predict the survival probability of patients in 1, 3, and 5 years.Results: 8 genes (VPREB3, TPBG, LRFN4, CD83, GIMAP6, PRMT8, WASF1, and F12) were identified as prognostic biomarkers. The GEO validation dataset demonstrated the risk model had good generalization effect. Significantly enrichment level of cell cycle-related pathway and lower content of CD8(+) T cells infiltration in the high-risk group when compared to low-risk group. Morever, the patients were from the intersection of high-TMB and low-risk groups showed the best prognosis. The nomogram demonstrated good consistency with practical outcomes in predicting the survival rate over 1, 3, and 5 years.Conclusion: The risk model demonstrate good prognostic predictive ability. The patients from the intersection of low-risk and high-TMB groups are not only more sensitive response to but also more likely to benefit from immune-checkpoint-inhibitors (ICIs) treatment.
The objective of this study was to develop and evaluate a pulsatile drug delivery system based on drug-containing hard gelatin capsules, which were coated with a swelling layer and an outer insoluble, water-permeable polymeric coating. An inner pressure developed by the swelling layer resulted in the rupture of the outer coating. Preliminary studies with a simulated rupture test demonstrated the dependence of the lag time prior to rupture on the properties of the coating, such as its water permeability and mechanical strength. The lag time increased with a higher coating level, but decreased with the addition of the hydrophilic pore former, hydroxypropyl methylcellulose. Increasing the amount of the swelling layer decreased the lag time. The coated capsules took up release medium at a nearly constant rate until a critical maximum was reached, where the swelling pressure was sufficient to rupture the outer coating. The rate of medium uptake decreased with increasing coating level, while the extent of medium uptake was almost the same for the different coating levels. A hydrophobic particulate material, magnesium stearate, was added to the coating layer to reduce the mechanical strength and therefore the lag time. The test conditions, such as surfactant addition to the release medium or floating vs. complete immersion of capsules in the medium, affected the lag time.
Systemic juvenile idiopathic arthritis (sJIA) is a severe autoinflammatory disorder with a still not clearly defined molecular mechanism. To better understand the disease, we used scattered datasets from public domains and performed a weighted gene coexpression network analysis (WGCNA) to identify key modules and hub genes underlying sJIA pathogenesis. Two gene expression datasets, GSE7753 and GSE13501, were used to construct the WGCNA. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were applied to the genes and hub genes in the sJIA modules. Cytoscape was used to screen and visualize the hub genes. We further compared the hub genes with the genome-wide association study (GWAS) genes and used a consensus WGCNA to verify that our conclusions were conservative and reproducible across multiple independent datasets. A total of 5,414 genes were obtained for WGCNA, from which highly correlated genes were divided into 17 modules. The red module demonstrated the highest correlation with the sJIA module (r = 0.8, p = 3e -29), whereas the green-yellow module was found to be closely related to the non-sJIA module (r = 0.62, p = 1e -14). Functional enrichment analysis demonstrated that the red module was mostly enriched in the activation of immune responses, infection, nucleosomes, and erythrocytes, and the green-yellow module was mostly enriched in immune responses and inflammation. Additionally, the hub genes in the red module were highly enriched in erythrocyte differentiation, including ALAS2, AHSP, TRIM10, TRIM58, and KLF1. The hub genes from the green-yellow module were mainly associated with immune responses, as exemplified by the genes KLRB1, KLRF1, CD160, and KIRs. We identified sJIA-related modules and several hub genes that might be associated with the development of sJIA. Particularly, the modules may help understand the mechanisms of sJIA, and the hub genes may become biomarkers and therapeutic targets of sJIA in the future.
Background The commercial success of monoclonal antibodies (Mabs) has made biological therapeutics attractive to pharmaceutical companies. The priority of biopharmaceutical companies is to acquire and develop cell lines that enable them to manufacture biologics quickly, consistently, and economically. Clone selection is a critical process for cell line development. However, the traditional clone selection process requires the evaluation of large numbers of clones using cell growth rate, cell densities and titer, product quality, and so on. Methods To improve efficiency of the clone selection strategies, we developed a relative titer (RT) prediction model by the quantitative information extracted from microscope images during the cell line development process. The performance of this RT prediction model was further evaluated with 50 clones from 5 different cell lines. Results The RT prediction model was able to predict high producers from a given data set when the same host cells were used. Although inaccurate prediction occurred when different host cell was used, this RT prediction model may serve as an excellent proof of concept study that quantitative information from cell line development images provides valuable information to facilitate the cell line development process. Conclusions Here, we present the first predictive model that can be used to estimate the relative productivity of Chinese hamster ovaries (CHO) clones during the cell line development. Additional experiments are currently in process to further improve the RT predictive model. Nevertheless, our current study will serve as a foundation for more prediction models for cell line development that can facilitate the selection of clones.
The occurrence of metastasis is a serious risk for renal cell carcinoma (RCC) patients. In order to develop novel therapeutic approaches to control the progression of metastatic RCC, it is of urgent need to understand the molecular mechanisms underlying RCC metastasis and identify prognostic markers of metastatic risk. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been known to be closely associated with extracellular matrix (ECM) turnover, which plays a highly active role in tumor metastasis. Recent studies have shown that immunophilin FK-506-binding protein 51 (FKBP51) may be important for the regulation of ECM function, and exert effects on the invasion and migration of tumor cells. However, the mechanisms underlying these activities remain unclear. The present study detected the role of FKBP51 in clear cell renal cell carcinoma (ccRCC), the most common subtype of RCC, and found that FKBP51 significantly promotes ccRCC invasion and migration by binding with the TIMP3, connecting TIMP3 with Beclin1 complex and increasing autophagic degradation of TIMP3. Given the important roles that TIMPs/MMPs play in ECM regulation and remodeling, our findings will provide new perspective for future investigation of the regulation of metastasis of kidney cancer and other types of cancer.
Anti-TNF inhibitors are efficacious in the treatment of chronic inflammatory diseases such as rheumatoid arthritis (RA), Crohn's disease (CD), juvenile idiopathic arthritis (JIA), and ankylosing spondylitis (AS). However, more and more clinical case reports revealed that anti-TNF inhibitors could increase the risk of viral, fungal, and bacterial (especially intracellular) infection. In this study, based on Immune Epitope Database (IEDB) online B cell epitope prediction and the knowledge of TNF three dimensional (3D) structure we developed a novel vaccine (DTNF114-TNF114) that targeting TNF epitope 1–14, which produced antibodies only partially binding to trans-membrane TNF (tmTNF), therefore partially sparing tmTNF-TNFR1/2 interaction. Immunization with DTNF114-TNF114 significantly protected and prolonged the survival rate of mice challenged with lipopolysaccharide (LPS); and in the mCherry expressing Mycobacterium bovis Bacillus Calmette-Guérin (mCherry-BCG) infection model, DTNF114-TNF114 immunization significantly decreased soluble TNF (solTNF) level in serum, meanwhile did not suppress host immunity against infection. Thus, this novel and infection concern-free vaccine provides a potential alternative or supplement to currently clinically used anti-TNF inhibitors.
Discovering new serological markers of Mycobacterium tuberculosis (MTB) infection and establishing a rapid and efficient detection technology is of great significance for the prevention and control of tuberculosis. In this study, we established an exponentially modified protein abundance index (emPAI) value-assisted strategy to investigate and improve the screening efficiency of serological biomarkers of tuberculosis. First, we used LC-MS/MS to analyse MTB culture filtrate proteins (MTB-CFPs), and 632 MTB proteins were identified. Then, the characteristic values of MTB-CFPs - including emPAI value, molecular weight (Mw), isoelectric point (pI), grand average of hydropathy (GRAVY), transmembrane domain (TMD) and functional groups were calculated. Next, we successfully prepared 10 MTB proteins with emPAI value > 1.0 and recombinantly expressed these proteins in Escherichia coli. At the same time, 3 MTB proteins with emPAI between 0.1 and 0.5 were randomly selected as the control groups, and the immunogenicity of the recombinant MTB proteins was detected using ELISA. The sensitivity and receiver operating characteristic (ROC) curves were calculated for each recombinant MTB protein. The results showed that the areas under the curve (AUC) value of Rv2031c, Rv0577, Rv0831c, Rv0934 and Rv3248c were all higher than those of Rv3875 (AUC, 0.6643). Further analysis of the relationship between emPAI value and antibody sensitivity, AUC value and antibody affinity in mice immunized with recombinant MTB protein showed that emPAI values were positively correlated with them, and R-squared value ranged from 0.64 to 0.79. The only exception was ESAT-6 (encoded by the Rv3875 gene), which AUC value was relatively low owing to its strong immunosuppressive properties. This study provides a rationale for the serological marker screening of emPAI-assisted tuberculosis clinical test. The results also provide new technical support for the screening of candidate serological markers of infectious diseases in the future.
Blocking inhibitory signaling and engaging stimulatory signaling have emerged as important therapeutic modalities for cancer immunotherapy. This study aimed to investigate immunomodulatory features of three recombinant costimulatory ligand proteins in a mouse model, which are extracellular domains of OX40-ligand (OX40L), 4-1BB-ligand (4-1BBL), or two domains in tandem, fused with the transmembrane domain of diphtheria toxin (DTT), named DTT-COS1, DTT-COS2, and DTT-COS12, respectively. In vitro study showed that DTT-COS1 and DTT-COS12 had immunological activity increasing the ratio of CD8/CD4 T cells. Treatments with DTT-COS1 and DTT-COS12 dramatically generated immune protection against the B16F10 tumor challenge in both prophylactic and therapeutic efficacy. Furthermore, regarding tumor microenvironment (TME) immunomodulation, DTT-COS1 treatment increased the proportion of CD4+ effector T cells (Teff) and decreased the expression of a suppressive cytokine. Meanwhile, DTT-COS12 reduced regulatory T cells (Treg) and improved the level of stimulatory cytokines. In addition, endogenous antibodies against OX40L/4-1BBL were generated, which may help with antitumor responses. Unexpectedly, DTT-COS2 lacked antitumor effects in vitro and in vivo. Importantly, serum analysis of liver-function associated factors and pro-inflammatory cytokines demonstrated that treatments were safe formulations in mice without signs of systemic toxicity. Remarkably, DTT-COS1 and DTT-COS12 are functional immunomodulators for mouse B16F10 melanoma, creating practical preclinical value in cancer immunotherapy.
为了有效去除血清中的白喉毒素跨膜结构域抗体,提高检测的精准度,建立四氧化三铁纳米磁珠共价偶联载体蛋白对血清中载体蛋白抗体的去除方法,并评估去除效果;采用高温多元醇合成法制备表面包裹葡聚糖的四氧化三铁纳米颗粒,利用溴化氰将葡聚糖分子上的羟基活化为亚氨基碳酸酯,并与白喉毒素跨膜结构域通过氨基共价偶联,制得纳米磁珠-白喉毒素跨膜结构域抗体阻断剂;纳米磁珠-白喉毒素跨膜结构域抗体阻断剂与免疫过白喉毒素跨膜结构域-血管内皮生长因子或白喉毒素跨膜结构域-肿瘤坏死因子融合蛋白疫苗的小鼠抗血清进行孵育,以吸附去除白喉毒素跨膜结构域特异性抗体;对孵育前、后的抗血清进行酶联免疫吸附测定.结果表明:白喉毒素跨膜结构域抗体的去除率高达90% 以上,检测精准度显著提高;在37℃ 条件下,仅需孵育1 h即可充分去除血清中的白喉毒素跨膜结构域抗体.
Drug development targeting the most frequently mutation G12D of KRAS has great significance. As an attractive immunotherapy, cancer vaccines can overcome binding difficulties of small molecules; however, the weak immunogenicity and production difficulties of reported KRAS mutation vaccines limit their clinical application. To improve antigen-specific immune responses and Anti-Tumor effects on tumors expressing KRAS G12D mutation, we designed recombinant proteins containing KRAS peptide (amino acids 5-21) with G12D (called SP) in two forms: DTT-SP4 and DTSP. DTT-SP4 was constructed by fusing four copies of SP to the C-terminal of the translocation domain of diphtheria toxin (DTT), and DTSP was constructed by grafting SP onto DTT. The two vaccines in combination with aluminum hydroxide (Alum) and cytosine phosphoguanine (CpG) successfully induced conspicuous SP-specific humoral and cellular immune responses, and displayed prominent protective and therapeutic Anti-Tumor effects in mouse CT26 tumor models. Surprisingly, the DTSP-treated group displayed better Anti-Tumor effects in vivo compared with the DTT-SP4-treated and control groups. Moreover, 87.5 and 50% of DTSP-treated mice in the preventive and therapeutic models were tumor free, respectively. Notably, in the DTSP-treated group, the interferon-γ (IFN-γ) expression of T cells in vitro and the T-helper 1 (Th1)-related cytokine expression in tumor tissues indicated that the activated Th1 immune response may be involved in Anti-Tumor activity. Furthermore, DTSP treatment remarkably altered the subpopulation of T cells in splenocytes and tumor-infiltrating lymphocytes. The percentage of effector CD8+ T cells increased, whereas that of immunosuppressive CD4+Foxp3+ T cells remained reduced in the DTSP group. Dramatic tumor-inhibitory effects of DTSP, which is easily prepared, make it a more attractive strategy against KRAS G12D tumors.
概述了全球单克隆抗体药物产业化现状,并结合单克隆抗体药物开发的经验,对我国单克隆抗体药物产业化面临的挑战与机遇进行了分析,以期为相关研究者提供参考.
钙结合蛋白S100A9与炎症发生与肿瘤侵袭密切相关,是髓系来源的抑制性细胞(myeloid-derived suppressor cell,MDSC)的特异性标志物之一.本研究以霍乱毒素B亚基(CTB)五聚体为载体构建了一种靶向小鼠钙结合蛋白S100A9的重组多肽疫苗CTB-S100A9,并在大肠杆菌分泌表达系统中获得表达.经纯化后的重组CTB-S100A9五聚体蛋白辅以氢氧化铝佐剂免疫小鼠后能打破自身免疫耐受产生高滴度的S100A9抗体.在4T1小鼠乳腺癌的预防及治疗模型中,CTB-S 100A9疫苗均能够有效抑制肿瘤生长.进一步发现CTB-S100A9疫苗能够有效减少荷瘤小鼠外周血中Treg细胞的含量及粒细胞来源的MDSC,逆转抑制性肿瘤免疫环境,增强抗肿瘤免疫应答.本研究的动物实验都是在南京中医药大学附属中西医结合医院动物伦理委员会批准的动物护理和方案下进行.该研究表明,CTB-S100A9是一种良好的靶向肿瘤免疫环境的重组疫苗,具有较大临床应用的潜力.
Tumor neoantigens are ideal targets for cancer immunotherapy as they are recognized by host immune system as foreigners and can elicit tumor-specific immune responses. However, existing strategies utilizing RNA or long peptides for the neoantigen vaccines render limited immune responses since only 20-30% of neoantigens predicted in silico to bind MHC I molecules are capable of eliciting immune responses with the majority of responding T cells are CD4(+). Therefore, it warrants further exploration to enhance neoantigen-specific CD8(+) T cells responses. Since neoantigens are naturally weak antigens, we asked whether foreign T help epitopes could enhance their immunogenicity. In present study, we chose 4 weak B16F10 neoantigens as vaccine targets, and fused them to the transmembrane domain of diphtheria toxin, namely DTT-neoAg. Strikingly, the vaccine elicited anti-tumor CD8(+) T cells responses and enhanced tumor infiltration of both T cells and NK cells. Impressively, DTT-neoAg vaccine significantly deterred tumor growth with the inhibition rate reached 88% in the preventive model and 100% in the therapeutic model at low dose of tumor challenge. Furthermore, after second challenge with higher dose of tumor cells, 33.3% of the immunized mice remained tumor-free for 6 months in the therapeutic model. Because DTT is a non-toxic domain of diphtheria toxin, it may be not of great concern in terms of safety as a Th epitope provider. Thus, the fusion strategy employed by this study may become a feasible and powerful approach for development of personalized cancer vaccines.
Engagement of programmed death 1 receptor (PD-1) and its ligand PD-L1/2 induces a signal transduction pathway that inhibits the activity of tumor-infiltrating cytotoxic T lymphocytes and promotes tumor growth and metastasis. Antibodies blocking PD-1 or PD-L1 can restore antitumor T cell responses and cause long-term remission in a subset of cancer patients with advanced or refractory tumors. In this study, we asked whether PD-L1 vaccination could confer tumor control in mouse tumor models. To address the central tolerance toward self-molecules, we fused the extracellular domain of PD-L1 (PD-L1E) to the C-terminal of the translocation domain of diphtheria toxin (DTT). DTT is able to elicit CD4+ T cell responses required for inducing robust immune responses against self-molecules. The fusion molecule is called DPDL1E. When formulated with incomplete Freund's adjuvant (IFA), DPDL1E elicited robust immune responses biased toward the Th1 type and inhibited tumor growth in both preventive and therapeutic mouse tumor models. We further showed that the anti-DPDL1E sera blocked PD-L1 binding to PD-1 in vitro. The DPDL1E vaccination increased the levels of tumor-infiltrating T lymphocytes (TILs) and reduced the levels of myeloid-derived suppressor cells (MDSCs) as well as exhausted LAG3+PD-1+CD8+T cells. All of these data suggest that DPDL1E vaccination reverses the suppressive phenotype of the tumor microenvironment and that it is a promising strategy for cancer therapy.
Background/Aims: The abnormally activated EGFR promotes tumor growth, invasion and metastasis. Current therapeutics targeting EGFR have markedly improved the clinical outcome, but they are limited in use due to transient efficacy, frequent administration, high cost and significant toxicity. Methods: We rationally designed a multiepitope immunogen against EGFR, named as DEGFRm. The immunogen is composed of an epitope peptide (EGFR265-283) and the extracellular domain III (EGFR334-505) of mouse EGFR. EGFR265-283 is grafted onto the translocation domain of diphtheria toxin (DTT), and EGFR334-505 is fused to C-terminal of DTT. Next, the immunogenicity and anti-tumor efficacies of DEGFRm vaccine were examined in mouse tumor models. Results: When formulated with Alum and CpG, DEGFRm vaccine elicits Th 1 immune responses and inhibits tumor growth in both prophylactic and therapeutic mouse tumor models. Moreover, the tumor microvasculature is markedly reduced and the tumor infiltration of CD8+ T lymphocytes is greatly enhanced. Conclusions: These data suggest that active immunization with DEGFRm vaccine is a promising strategy for therapy of various EGFR+ cancers.
肿瘤坏死因子-alpha (tumor necrosis factor alpha,TNF-α)在多种疾病如类风湿关节炎等自身免疫病发病机理上起着至关重要的作用.TNF-α生物抑制剂,在临床上具有很好的疗效.由于TNF-α是一种高活性的炎症因子,直接将其作为疫苗,会对机体产生很大的毒性副作用.故需要对天然的TNF-α进行点突变研究,找到生物活性很低的但同时保持良好的免疫原性的突变分子.本研究对人TNF-α活性部位4个关键氨基酸残基(K11,Y87,Y119,A145)进行了点突变和突变蛋白的免疫原性研究.发现Y119N、Y119G、Y87H、Y87H/A145R、K11Y、K11F这6个突变蛋白的生物活性较天然TNF-α下降90%以上,而免疫原性不受点突变的影响.