Development of nanobodies targeting hepatocellular carcinoma and application of nanobody-based CAR-T technology.

BACKGROUND: Chimeric antigen receptor T (CAR-T) cell therapy, as an emerging anti-tumor treatment, has garnered extensive attention in the study of targeted therapy of multiple tumor-associated antigens in hepatocellular carcinoma (HCC). However, the suppressive microenvironment and individual heterogeneity results in downregulation of these antigens in certain patients' cancer cells. Therefore, optimizing CAR-T cell therapy for HCC is imperative. METHODS: In this study, we administered FGFR4-ferritin (FGFR4-HPF) nanoparticles to the alpaca and constructed a phage library of nanobodies (Nbs) derived from alpaca, following which we screened for Nbs targeting FGFR4. Then, we conducted the functional validation of Nbs. Furthermore, we developed Nb-derived CAR-T cells and evaluated their anti-tumor ability against HCC through in vitro and in vivo validation. RESULTS: Our findings demonstrated that we successfully obtained high specificity and high affinity Nbs targeting FGFR4 after screening. And the specificity of Nbs targeting FGFR4 was markedly superior to their binding to other members of the FGFR family proteins. Furthermore, the Nb-derived CAR-T cells, targeting FGFR4, exhibited significantly enhanced anti-tumor efficacy in both experiments when in vitro and in vivo. CONCLUSIONS: In summary, the results of this study suggest that the CAR-T cells derived from high specificity and high affinity Nbs, targeting FGFR4, exhibited significantly enhanced anti-tumor efficacy in vitro and in vivo. This is an exploration of FGFR4 in the field of Nb-derived CAR-T cell therapy for HCC, holding promise for enhancing safety and effectiveness in the clinical treatment of HCC in the future.

Nitrate-dependent anaerobic methane oxidation coupled to Fe(III) reduction as a source of ammonium and nitrous oxide.

'Candidatus Methanoperedens nitroreducens' is an archaeal methanotroph with global importance that links carbon and nitrogen cycles and great potential for sustainable operation of wastewater treatment. It has been reported to mediate the anaerobic oxidation of methane through a reverse methanogenesis pathway while reducing nitrate to nitrite. Here, we demonstrate that 'Ca. M. nitroreducens' reduces ferric iron forming ammonium (23.1 %) and nitrous oxide (N2O, 46.5 %) from nitrate. These results are supported with the upregulation of genes coding for proteins responsible for dissimilatory nitrate reduction to ammonium (nrfA), N2O formation (norV, cyt P460), and multiple multiheme c-type cytochromes for ferric iron reduction. Concomitantly, an increase in the N2O-reducing SJA-28 lineage and a decrease in the nitrite-reducing 'Candidatus Methylomirabilis oxyfera' are consistent with the changes in 'Ca. M. nitroreducens' end products. These findings demonstrate the highly flexible physiology of 'Ca. M. nitroreducens' in anaerobic ecosystems with diverse electron acceptor conditions, and further reveals its roles in linking methane oxidation to global biogeochemical cycles. 'Ca. M. nitroreducens' could significantly affect the bioavailability of nitrogen sources as well as the emission of greenhouse gas in natural ecosystems and wastewater treatment plants.

Deep insights into the biofilm formation mechanism and nitrogen-transformation network in a nitrate-dependent anaerobic methane oxidation biofilm.

Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) process offers a promising solution for simultaneously achieving methane emissions reduction and efficient nitrogen removal in wastewater treatment. Although nitrogen removal at a practical rate has been achieved by n-DAMO biofilm process, the mechanisms of biofilm formation and nitrogen transformation remain to be elucidated. In this study, n-DAMO biofilms were successfully developed in the membrane aerated moving bed biofilm reactor (MAMBBR) and removed nitrate at a rate of 159 mg NO3--N L-1 d-1. The obvious increase in the content of extracellular polymeric substances (EPS) indicated that EPS production was important for biofilm development. n-DAMO microorganisms dominated the microbial community, and n-DAMO bacteria were the most abundant microorganisms. However, the expression of biosynthesis genes for proteins and polysaccharides encoded by n-DAMO archaea was significantly more active compared to other microorganisms, suggesting the central role of n-DAMO archaea in EPS production and biofilm formation. In addition to nitrate reduction, n-DAMO archaea were revealed to actively express dissimilatory nitrate reduction to ammonium and nitrogen fixation. The produced ammonium was putatively converted to dinitrogen gas through the joint function of n-DAMO archaea and n-DAMO bacteria. This study revealed the biofilm formation mechanism and nitrogen-transformation network in n-DAMO biofilm systems, shedding new light on promoting the application of n-DAMO process.

The bioremediation of the typical persistent organic pollutants (POPs) by microalgae-bacteria consortia: A systematic review.

With industrialisation and the rapidly growing agricultural demand, many organic compounds have been leaked into the environment, causing serious damage to the biosphere. Persistent organic pollutants (POPs) are a type of toxic chemicals that are resistant to degradation through normal chemical, biological or photolytic approaches. With their stable chemical structures, POPs can be accumulated in the environment, and transported through wind and water, causing global environmental issues. Many researches have been conducted to remediate POPs contamination using various kinds of biological methods, and significant results have been seen. Microalgae-bacteria consortium is a newly developed concept for biological technology in contamination treatment, with the synergetic effects between microalgae and bacteria, their potential for pollutants degradation can be further released. In this review, two types of POPs (polychlorinated biphenyls and polycyclic aromatic hydrocarbons) are selected as the targeted pollutants to give a systematic analysis of the biodegradation through microalgae and bacteria, including the species selection, the identification of dominant enzymes, as well as the real application performance of the consortia. In the end, some outlooks and suggestions are given to further guide the development of applying microalgae-bacteria consortia in remediating POPs contamination. In general, the coculturing of microalgae and bacteria is a novel and efficient way to fulfil the advanced treatment of POPs in soil or liquid phase, and both monooxygenase and dioxygenase belonging to oxygenase play a vital role in the biodegradation of PCBs and PAHs. This review provides a general guide in the future investigation of biological treatment of POPs.

The receptor binding domain of SARS-CoV-2 Omicron subvariants targets Siglec-9 to decrease its immunogenicity by preventing macrophage phagocytosis.

The development of a vaccine specific to severe acute respiratory syndrome coronavirus 2 Omicron has been hampered due to its low immunogenicity. Here, using reverse mutagenesis, we found that a phenylalanine-to-serine mutation at position 375 (F375S) in the spike protein of Omicron to revert it to the sequence found in Delta and other ancestral strains significantly enhanced the immunogenicity of Omicron vaccines. Sequence FAPFFAF at position 371-377 in Omicron spike had a potent inhibitory effect on macrophage uptake of receptor-binding domain (RBD) nanoparticles or spike-pseudovirus particles containing this sequence. Omicron RBD enhanced binding to Siglec-9 on macrophages to impair phagocytosis and antigen presentation and promote immune evasion, which could be abrogated by the F375S mutation. A bivalent F375S Omicron RBD and Delta-RBD nanoparticle vaccine elicited potent and broad nAbs in mice, rabbits and rhesus macaques. Our research suggested that manipulation of the Siglec-9 pathway could be a promising approach to enhance vaccine response.

The construction of modular universal chimeric antigen receptor T (MU-CAR-T) cells by covalent linkage of allogeneic T cells and various antibody fragments.

BACKGROUND: Chimeric antigen receptor-T (CAR-T) cells therapy is one of the novel immunotherapeutic approaches with significant clinical success. However, their applications are limited because of long preparation time, high cost, and interpersonal variations. Although the manufacture of universal CAR-T (U-CAR-T) cells have significantly improved, they are still not a stable and unified cell bank. METHODS: Here, we tried to further improve the convenience and flexibility of U-CAR-T cells by constructing novel modular universal CAR-T (MU-CAR-T) cells. For this purpose, we initially screened healthy donors and cultured their T cells to obtain a higher proportion of stem cell-like memory T (TSCM) cells, which exhibit robust self-renewal capacity, sustainability and cytotoxicity. To reduce the alloreactivity, the T cells were further edited by double knockout of the T cell receptor (TCR) and class I human leukocyte antigen (HLA-I) genes utilizing the CRISPR/Cas9 system. The well-growing and genetically stable universal cells carrying the CAR-moiety were then stored as a stable and unified cell bank. Subsequently, the SDcatcher/GVoptiTag system, which generate an isopeptide bond, was used to covalently connect the purified scFvs of antibody targeting different antigens to the recovered CAR-T cells. RESULTS: The resulting CAR-T cells can perform different functions by specifically targeting various cells, such as the eradication of human immunodeficiency virus type 1 (HIV-1)-latenly-infected cells or elimination of T lymphoma cells, with similar efficiency as the traditional CAR-T cells did. CONCLUSION: Taken together, our strategy allows the production of CAR-T cells more modularization, and makes the quality control and pharmaceutic manufacture of CAR-T cells more feasible.

Highly efficient degradation of acetaminophen via nano zero-valent iron biochar with periodate system at low temperature.

The development of more efficient advanced oxidation systems for serving various advanced treatment of wastewater is quite necessary and urgent. In this study, a nano-zero valent iron/periodate (nZVI-BC/PI) advanced oxidation system has been constructed, achieving a rapid degradation of acetaminophen (ACT, 1 mg/L) within 1 min (100 % at pH = 11) at low temperature (5℃). This system shows a great degradation in a wide range of pH (1 âˆ¼ 11), improving the pH limitation of PI oxidation system. During the reaction process, ·OH as the main active species collaborate with 1O2, Fe (IV), ·O2- and electron transfer to degrade ACT. In this system, iron ion leaching is low (0.019 mg/L), ACT was effectively degraded (74.36 %∼97.32 %) under different water, moreover, the material has an expected recyclability. The research provides a significant guidance for the advanced treatment of wastewater especially in cold regions.

Generation of a new therapeutic D-peptide that induces the differentiation of acute myeloid leukemia cells through A TLR-2 signaling pathway.

Acute myeloid leukemia (AML) is caused by clonal disorders of hematopoietic stem cells. Differentiation therapy is emerging as an important treatment modality for leukemia, given its less toxicity and wider applicable population, but the arsenal of differentiation-inducing agents is still very limited. In this study, we adapted a competitive peptide phage display platform to search for candidate peptides that could functionally induce human leukemia cell differentiation. A monoclonal phage (P6) and the corresponding peptide (pep-P6) were identified. Both L- and D-chirality of pep-P6 showed potent efficiency in inducing AML cell line differentiation, driving their morphologic maturation and upregulating the expression of macrophage markers and cytokines, including CD11b, CD14, IL-6, IL-1ß, and TNF-α. In the THP-1 xenograft animal model, administration of D-pep-P6 was effective in inhibiting disease progression. Importantly, exposure to D-pep-P6 induced the differentiation of primary human leukemia cells isolated AML patients in a similar manner to the AML cell lines. Further mechanism study suggested that D-pep-P6 induced human leukemia cell differentiation by directly activating a TLR-2 signaling pathway. These findings identify a novel D-peptide that may promote leukemia differentiation therapy.

Combined transcriptomic and metabolomic analyses of temperature response of microalgae using waste activated sludge extracts for promising biodiesel production.

Waste activated sludge (WAS) as one of the major pollutants with a significant annual production, has garnered significant attention regarding its treatment and utilization. If improperly discharged, it not only caused environmental pollution but also led to the wastage of valuable resources. In this study, the microalgae growth and lipid accumulation using waste activated sludge extracts (WASE) under different temperature conditions were investigated. The highest lipid content (59.13%) and lipid productivity (80.41 mg L-1 d-1) were obtained at cultivation temperatures of 10 and 25 °C, respectively. It was found that microalgae can effectively utilize TN/TP/NH4+-N and other nutrients of WASE. The highest utilization rates of TP, TN and NH4+-N were achieved at a cultivation temperature of 10 °C, reaching 84.97, 77.49 and 92.32%, respectively. The algal fatty acids had carbon chains predominantly ranging from C14 to C18, making them suitable for biodiesel production. Additionally, a comprehensive analysis of transcriptomics and metabolomics revealed up-regulation of genes associated with triglyceride assembly, the antioxidant system of algal cells, and cellular autophagy, as well as the accumulation of metabolites related to the tricarboxylic acid (TCA) cycle and lipids. This study offers novel insights into the microscopic mechanisms of microalgae culture using WASE and approaches for the resource utilization of sludge.

New insights into rare earth element-induced microalgae lipid accumulation: Implication for biodiesel production and adsorption mechanism.

A coupling technology for lipid production and adsorption of rare earth elements (REEs) using microalgae was studied in this work. The microalgae cell growth, lipid production, biochemical parameters and lipid profiles were investigated under different REEs (Ce3+, Gd3+and La3+). The results showed that the maximum lipid production was achieved at different concentrations of REEs, with lipid productivities of 300.44, 386.84 and 292.19 mg L-1 d-1 under treatment conditions of 100 µg L-1 Ce3+, 250 µg L-1 Gd3+ and 1 mg L-1 La3+, respectively. Moreover, the adsorption efficiency of Ce3+, Gd3+ and La3+exceeded 96.58 %, 93.06 % and 91.3 % at concentrations of 25-1000 µg L-1, 100-500 µg L-1 and 0.25-1 mg L-1, respectively. In addition, algal cells were able to adsorb 66.2 % of 100 µg L-1 Ce3+, 48.4 % of 250 µg L-1 Gd3+ and 59.9 % of 1 mg L-1 La3+. The combination of extracellular polysaccharide and algal cell wall could adsorb 25.2 % of 100 µg L-1 Ce3+, 44.5 % of 250 µg L-1 Gd3+ and 30.5 % of 1 mg L-1 La3+, respectively. These findings indicated that microalgae predominantly adsorbed REEs through the intracellular pathway. This study elucidates the mechanism of effective lipid accumulation and adsorption of REEs by microalgae under REEs stress conditions. It establishes a theoretical foundation for the efficient microalgae lipid production and REEs recovery from wastewater or waste residues containing REEs.

Pollution characteristics and potential health effects of airborne microplastics and culturable microorganisms during urban haze in Harbin, China.

In this study, active sampling technology was used to collect microplastics (MPs) and microorganisms simultaneously on haze days in Harbin, China. Airborne MPs concentrations in Junior high school (162.4 ± 44.6 particles/m3) with high vehicular and pedestrian traffic was higher than those in University (63.2 ± 21.8 particles/m3) and Park (12.8 ± 5.5 particles/m3). More airborne MPs were detected in the night samples than in the morning and noon samples. The majority (69.06 %) of airborne MPs measured less than 100 µm, with fibers (69.4 %) being the predominant form. Polyesters and polyethylene were the dominant polymers. In addition, airborne MPs concentrations were positively correlated with microorganisms and PM10 concentrations, and the health hazards associated with microorganisms and MPs exposure via inhalation far exceeded those associated with skin contact, which can serve as a theoretical foundation for considering MPs as indicators of air quality in the future.

Revisiting the Engineering Roadmap of Nitrate/Nitrite-Dependent Anaerobic Methane Oxidation.

Nitrate/nitrite-dependent anaerobic oxidation of methane (n-DAMO) is a recently discovered process, which provides a sustainable perspective for simultaneous nitrogen removal and greenhouse gas emission (GHG) mitigation by using methane as an electron donor for denitrification. However, the engineering roadmap of the n-DAMO process is still unclear. This work constitutes a state-of-the-art review on the classical and most recently discovered metabolic mechanisms of the n-DAMO process. The versatile combinations of the n-DAMO process with nitrification, nitritation, and partial nitritation for nitrogen removal are also clearly presented and discussed. Additionally, the recent advances in bioreactor development are systematically reviewed and evaluated comprehensively in terms of methane supply, biomass retention, membrane requirement, startup time, reactor performance, and limitations. The key issues including enrichment and operation strategy for the scaling up of n-DAMO-based processes are also critically addressed. Moreover, the challenges inherent to implementing the n-DAMO process in practical applications, including application scenario recognition, GHG emission mitigation, and operation under realistic conditions, are highlighted. Finally, prospects as well as opportunities for future research are proposed. Overall, this review provides a roadmap for potential applications and further development of the n-DAMO process in the field of wastewater treatment.

Resonant-cavity-enhanced infrared detector incorporating an ultra-thin type-II superlattice: design and simulation.

A resonant-cavity-enhanced type-II superlattice (T2SL) infrared detector based on a metal grating has been designed to address the weak photon capture and low quantum efficiency (QE) issues of T2SL infrared detectors. Simulations have been conducted to analyze the effects of metal grating parameters, including length, thickness, and incident angle, on the spectral response and absorptivity of the absorption layers in T2SL infrared detectors. By optimizing the design, an appropriate resonant cavity structure was obtained. Research results indicate that the resonant cavity structure can significantly enhance the absorption rate of a T2SL infrared detector with a 0.2 µm thick absorption layer in the 3-5 µm wavelength range, observing peak absorption rates at 3.82 µm and 4.73 µm, with values of 97.6% and 98.2%, respectively. The absorption rate of the 0.2 µm thick T2SL absorption layer at peak wavelengths increased from 6.03% and 2.3% to 54.48% and 27.91%, respectively. The implementation of the resonant-cavity-enhanced T2SL infrared detector improves the QE while reducing absorption layer thickness, thus opening up new avenues for improving T2SL detector performance.

Nanobody-derived bispecific CAR-T cell therapy enhances the anti-tumor efficacy of T cell lymphoma treatment.

T cell lymphoma (TCL) is a highly heterogeneous group of diseases with a poor prognosis and low 5-year overall survival rate. The current therapeutic regimens have relatively low efficacy rates. Clinical studies of single-target chimeric antigen receptor T cell (CAR-T cell) therapy in T lymphocytes require large and multiple infusions, increasing the risks and cost of treatment; therefore, optimizing targeted therapy is a way to improve overall prognosis. Despite significant advances in bispecific CAR-T cell therapy to avoid antigen escape in treatment of B cell lymphoma, applying this strategy to TCL requires further investigation. Here, we constructed an alpaca nanobody (Nb) phage library and generated high-affinity and -specificity Nbs targeting CD30 and CD5, respectively. Based on multiple rounds of screening, bispecific NbCD30-CD5-CAR T cells were constructed, and their superior anti-tumor effect against TCL was validated in vitro and in vivo. Our findings demonstrated that Nb-derived bispecific CAR-T cells significantly improved anti-tumor efficacy in TCL treatment compared with single-target CAR-T cells and bispecific single chain variable fragment (scFv)-derived CAR-T cells. Because Nbs are smaller and less immunogenic, the synergistic effect of Nb-based bispecific CAR-T cells may improve their safety and efficacy in future clinical applications.

A Mosaic Nanoparticle Vaccine Elicits Potent Mucosal Immune Response with Significant Cross-Protection Activity against Multiple SARS-CoV-2 Sublineages.

Because of the rapid mutation and high airborne transmission of SARS-CoV-2, a universal vaccine preventing the infection in the upper respiratory tract is particularly urgent. Here, a mosaic receptor-binding domain (RBD) nanoparticle (NP) vaccine is developed, which induces more RBD-targeted type IV neutralizing antibodies (NAbs) and exhibits broad cross-protective activity against multiple SARS-CoV-2 sublineages including the newly-emerged BF.7, BQ.1, XBB. As several T-cell-reactive epitopes, which are highly conserved in sarbecoviruses, are displayed on the NP surface, it also provokes potent and cross-reactive cellular immune responses in the respiratory tissue. Through intranasal delivery, it elicits robust mucosal immune responses and full protection without any adjuvants. Therefore, this intranasal mosaic NP vaccine can be further developed as a pan-sarbecovirus vaccine to block the viral entrance from the upper respiratory tract.

Deep insights into the population shift of n-DAMO and Anammox in granular sludge: From sidestream to mainstream.

Granular sludge combined n-DAMO and Anammox (n-D/A) is an energy-efficient biotechnique for the simultaneous removal of nitrogen and dissolved methane from wastewater. However, the lack of knowledge so far about the metabolic interactions between n-DAMO and Anammox in response to operation condition in granular sludge restrains the development of this biotechnology. To address this gap, three independent membrane granular sludge reactors (MGSRs) were designed to carry out the granule-based n-D/A process under different conditions. We provided the first deep insights into the metabolic interactions between n-DAMO and Anammox in granular sludge via combined metagenomic and metatranscriptomic analyses. Our study unveiled a clear population shift of n-DAMO community from Candidatus Methanoperedens to Candidatus Methylomirabilis from sidestream to mainstream. Candidatus Methanoperedens with relative abundance of 25.2% played the major role in nitrate reduction and methane oxidation under sidestream condition, indicated by the high expression activities of mcrA and narG. Candidatus Methylomirabilis dominated the microbial community under mainstream condition with relative abundance of 32.1%, supported by the high expression activities of pmoA and hao. Furthermore, a transition of Anammox population from Candidatus Kuenenia to Candidatus Brocadia was also observed from sidestream to mainstream. Candidatus Kuenenia and Candidatus Brocadia jointly contributed to the primary anaerobic ammonium oxidation suggested by the high expression value of hdh and hzs. Candidatus Methylomirabilis was speculated to perform ammonium oxidation mediated by pMMO under mainstream condition. These findings might help to reveal the microbial interactions and ecological niches of n-DAMO and Anammox microorganisms, shedding light on the optimization and management of the granule-based n-D/A system.

Improved sequential production of hydrogen and caproate by addition of biochar prepared from cornstalk residues.

This study proposes a new model in which ethanol and acetate produced by dark fermentation are processed by Clostridium kluyveri for chain elongation to produce caproate with an addition of biochar prepared from cornstalk residues after acid pretreatment and enzymatic hydrolysis (AERBC) in the dark fermentation and chain elongation processes. The results show a 6-25% increase in hydrogen production in dark fermentation with adding AERBC, and the maximum concentration of caproate in the new model reached 1740 mg/L, 61% higher than that in the control group. In addition, caproate was obtained by dark fermentation, using liquid metabolites as substrates with an initial pH range of 6.5-7.5. Finally, the electron balance and electron transfer efficiency in the new model were analyzed, and the role of AERBC in dark fermentation and chain elongation was investigated. This study provides a new reference for the use of dark-fermented liquid metabolites and cornstalk residue.

Thermophilic microorganisms involved in the nitrogen cycle in thermal environments: Advances and prospects.

Thermophilic microorganisms mediated significant element cycles and material conversion in the early Earth as well as mediating current thermal environments. Over the past few years, versatile microbial communities that drive the nitrogen cycle have been identified in thermal environments. Understanding the microbial-mediated nitrogen cycling processes in these thermal environments has important implications for the cultivation and application of thermal environment microorganisms as well as for exploring the global nitrogen cycle. This work provides a comprehensive review of different thermophilic nitrogen-cycling microorganisms and processes, which are described in detail according to several categories, including nitrogen fixation, nitrification, denitrification, anaerobic ammonium oxidation, and dissimilatory nitrate reduction to ammonium. In particular, we assess the environmental significance and potential applications of thermophilic nitrogen-cycling microorganisms, and highlight knowledge gaps and future research opportunities.

Cutting-Force Modeling Study on Vibration-Assisted Micro-Milling of Bone Materials.

This study aims to enhance surgical safety and facilitate patient recovery through the investigation of vibration-assisted micro-milling technology for bone-material removal. The primary objective is to reduce cutting force and improve surface quality. Initially, a predictive model is developed to estimate the cutting force during two-dimensional (2D) vibration-assisted micro-milling of bone material. This model takes into account the anisotropic structural characteristics of bone material and the kinematics of the milling tool. Subsequently, an experimental platform is established to validate the accuracy of the cutting-force model for bone material. Micro-milling experiments are conducted on bone materials, with variations in cutting direction, amplitude, and frequency, to assess their impact on cutting force. The experimental results demonstrate that selecting appropriate machining parameters can effectively minimize cutting force in 2D vibration-assisted micro-milling of bone materials. The insights gained from this study provide valuable guidance for determining cutting parameters in vibration-assisted micro-milling of bone materials.

Enhancement of CAR-T cell activity against cholangiocarcinoma by simultaneous knockdown of six inhibitory membrane proteins.

BACKGROUND: Existing treatments for cholangiocarcinoma have poor efficacy. However, chimeric antigen receptor-T (CAR-T) cells are emerging as a potential therapeutic strategy. Solid tumors possess multiple adverse factors in an immunosuppressive microenvironment that impair CAR-T cell infiltration and function. This study aimed to improve the function of CAR-T cells through knock down immune checkpoints and immunosuppressive molecular receptors. METHODS: We evaluated the expression of epidermal growth factor receptor (EGFR) and B7 homolog 3 protein (B7H3) antigens in cholangiocarcinoma tissues using immunohistochemistry and screened specific immune checkpoints in the cholangiocarcinoma microenvironment via flow cytometry. Subsequently, we engineered CAR-T cells targeting EGFR and B7H3 antigens. We simultaneously knocked down immune checkpoints and immunosuppressive molecular receptors in CAR-T cells by constructing two clusters of small hairpin RNAs and evaluated the engineered CAR-T cells for antitumor activity both in vitro, using tumor cell lines and cholangiocarcinoma organoid models, and in vivo, using humanized mouse models. RESULTS: We observed high expression of EGFR and B7H3 antigens in cholangiocarcinoma tissues. EGFR-CAR-T and B7H3-CAR-T cells demonstrated specific anti-tumor activity. We found an abundance of programmed cell death protein 1 (PD-1), T cell immunoglobulin and mucin domain-containing protein 3 (Tim-3), and T cell immunoglobulin and ITIM domain (Tigit) on infiltrated CD8+ T cells in the cholangiocarcinoma microenvironment. We then decreased the expression of these 3 proteins on the surface of CAR-T cells, named PTG-scFV-CAR-T cells. Furthermore, we knocked-down the expression of transforming growth factor beta receptor (TGFßR), interleukin-10 receptor (IL-10R), and interleukin-6 receptor (IL-6R) of PTG-scFV-CAR-T cells. Those cells, named PTG-T16R-scFV-CAR-T cells, potently killed tumor cells in vitro and promoted apoptosis of tumor cells in a cholangiocarcinoma organoid model. Finally, the PTG-T16R-scFv-CAR-T cells showed greater inhibitory effect on tumor growth in vivo, and were superior in prolonging the survival of mice. CONCLUSIONS: Our results revealed that PTG-T16R-scFV-CAR-T cells with knockdown of sextuplet inhibitory molecules exhibited strong immunity against cholangiocarcinoma and long-term efficacy both in vitro and in vivo. This strategy provides an effective and personalized immune cell therapy against cholangiocarcinoma.