Rapid Evaluation of Lung Adenocarcinoma Progression by Detecting Plasma Extracellular Vesicles with Lateral Flow Immunoassays.

Extracellular vesicles (EVs) have been widely used in liquid biopsy to diagnose and monitor cancers. However, since samples containing EVs are usually body fluids with complex components, the cumbersome separation steps for EVs during detection limit the clinical application and promotion of EV detection methods. In this study, a dyad lateral flow immunoassay (LFIA) strip for EV detection, containing CD9-CD81 and EpCAM-CD81, was developed to detect universal EVs and tumor-derived EVs, respectively. The dyad LFIA strip can directly detect trace plasma samples and effectively distinguish the cancerous sample from healthy plasma. The limit of detection for detecting universal EVs was 2.4 × 105 mL-1. The whole immunoassay can be performed in 15 min and only consumes 0.2 µL of plasma for one test. To improve the suitability of a dyad LFIA strip in complex scenarios, a smartphone-based photographic method was developed, which provided a consistency of 96.07% to a specialized fluorescence LFIA strip analyzer. In further clinical testing, EV-LFIA discriminated lung cancer patient groups (n = 25) from healthy controls (n = 22) with 100% sensitivity and 94.74% specificity at the best cutoff. The detection of EpCAM-CD81 tumor EVs (TEVs) in lung cancer plasma revealed the differences in TEVs in individuals, which reflected the different treatment effects. TEV-LFIA results were compared with CT scan findings (n = 30). The vast majority of patients with increased TEV-LFIA detection intensity had lung masses that enlarged or remained unchanged in size, which reported no response to treatment. In other words, patients who reported no response (n = 22) had a high TEV level compared with patients who reported a response to treatment (n = 8). Taken together, the developed dyad LFIA strip provides a simple and rapid platform to characterize EVs to monitor lung cancer therapy outcomes.

Platinum nanoparticles (PtNPs)-based CRISPR/Cas12a platform for detection of nucleic acid and protein in clinical samples.

Early rapid screening diagnostic assay is essential for the identification, prevention, and evaluation of many contagious or refractory diseases. The optical density transducer created by platinum nanoparticles (PtNPs) (OD-CRISPR) is reported in the present research as a cheap and easy-to-execute CRISPR/Cas12a-based diagnostic platform. The OD-CRISPR uses PtNPs, with ultra-high peroxidase-mimicking activity, to increase the detection sensitivity, thereby enabling the reduction of detection time and cost. The OD-CRISPR can be utilized to identify nucleic acid or protein biomarkers within an incubation time of 30-40min in clinical specimens. In the case of taking severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) N gene as an instance, when compared to a quantitative reverse transcription-polymerase chain reaction (RT-qPCR), the OD-CRISPR test attains a sensitivity of 79.17% and a specificity of 100%. In terms of detecting prostate-specific antigen (PSA), aptamer-based OD-CRISPR assay achieves the least discoverable concentration of 0.01 ng mL-1. In general, the OD-CRISPR can detect nucleic acid and protein biomarkers, and is a potential strategy for early rapid screening diagnostic tools.

Application of the amplification-free SERS-based CRISPR/Cas12a platform in the identification of SARS-CoV-2 from clinical samples.

The control of contagious or refractory diseases requires early, rapid diagnostic assays that are simple, fast, and easy-to-use. Here, easy-to-implement CRISPR/Cas12a-based diagnostic platform through Raman transducer generated by Raman enhancement effect, term as SERS-CRISPR (S-CRISPR), are described. The S-CRISPR uses high-activity noble metallic nanoscopic materials to increase the sensitivity in the detection of nucleic acids, without amplification. This amplification-free platform, which can be performed within 30-40 min of incubation time, is then used for detection of SARS-CoV-2 derived nucleic acids in RNA extracts obtained from nasopharyngeal swab specimens (n = 112). Compared with the quantitative reverse transcription polymerase chain reaction (RT-qPCR), the sensitivity and specificity of S-CRISPR reaches 87.50% and 100%, respectively. In general, the S-CRISPR can rapidly identify the RNA of SARS-CoV-2 RNA without amplification and is a potential strategy for nucleic acid point of care test (POCT).

On-site differential diagnostic detection of HP-PRRSV and C-PRRSV using EuNPs-mAb fluorescent probe-based immunoassay.

Porcine reproductive and respiratory syndrome virus (PRRSV) has caused worldwide economic losses in the swine industry. Pigs infected with highly pathogenic (HP)-PRRSV display more severe symptoms than those infected with classical (C)-PRRSV. A rapid, sensitive, and reliable detection method to distinguish between HP-PRRSV and C-PRRSV is needed. In this study, we prepared a monoclonal antibody from a hybridoma that can distinguish HP-PRRSV(including TP, QJ, LQ, JN-HS, and TY strain) from C-PRRSV (CH-1A strain) using cell surface-fluorescence immunosorbent assays (CSFIA). Based on this monoclonal antibody (4D5), we developed a europium microsphere-based lateral flow immunochromatographic strip (EuNPs-LFICS) for the differential diagnostic detection of HP-PRRSV and C-PRRSV. Under optimized conditions, the method was rapid (15 min), sensitive (LOD: 2.57 ng mL-1, 606 TCID50/0.1 mL), selective for HP-PRRSV detection, and quantitative (DLR: 3.56-228 ng mL-1). In clinical samples, the EuNPs-LFICS assay was largely consistent with PCR results, indicating its practical clinical application.

A new method for rapid screening of hybridoma cell clones secreting paired antibodies using sandwich cell surface fluorescence immunosorbent assay.

Traditional methods of screening antibody pairs through ELISA-based methods are time-consuming and burdensome, which is not conducive for the rapid establishment of antigen detection methods. Hence, we developed a new method based on the sandwich cell surface fluorescence immunosorbent assay (SCSFIA) for rapid screening of paired antibodies. In this method, the capture antibodies were anchored to the hybridoma cells membrane through the lipid derivative Oleyl-PEG4000-NHS. Goat anti-mouse antibodies (blocking agent) were added to block the Fc fragment of the capture antibodies. The capture antibodies' Fab fragment can specifically bind the added antigen and form the capture antibodies-antigens complex (immunocomplexes). If the antibodies secreted by hybridoma cells could recognize the immunocomplexes. A double antibody sandwich structure would form on the cell surface based on the specific binding of antigens and antibodies. The hybridoma cells would be stained with anti-mouse IgG-Fc-FITC antibodies. We first used anti-pseudorabies virus (anti-PRV) cells and anti-porcine epidemic diarrhea virus (anti-PEDV) cells to verify the new method. Then, we used this method to successfully screen 5 hybridoma cell clones secreting paired antibodies against Avian influenza A (H7N9) virus within 15 days after fusion. These results showed that this method is suitable for the screening of paired antibodies in a variety of virus. Compared with the traditional method of obtaining paired antibodies, this method can greatly shortens the time needed to screen paired antibodies and improves screening efficiency, indicating that it is a promising method for paired antibodies discovery.

Fermentation, Purification, and Tumor Inhibition of a Disulfide-Stabilized Diabody Against Fibroblast Growth Factor-2.

Angiogenesis is considered one of the hallmarks of cancer and plays a critical role in the development of tumor. Fibroblast growth factor 2 (FGF-2) is a member of the FGF family and participates in excessive cancer cell proliferation and tumor angiogenesis. Thus, targeting FGF-2 was considered to be a promising anti-tumor strategy. A disulfide-stabilized diabody (ds-Diabody) against FGF-2 was produced in Pichia pastoris (GS115) by fermentation and the anti-tumor activity was analyzed. The novel 10-L fed batch fermentation with newly designed media was established, and the maximum production of the ds-Diabody against FGF-2 reached 210.4 mg/L. The ds-Diabody against FGF-2 was purified by Ni2+ affinity chromatography and DEAE anion exchange chromatography. The recombinant ds-Diabody against FGF-2 could effectively inhibit proliferation, migration, and invasion of melanoma and glioma tumor cells stimulated by FGF-2. Furthermore, xenograft tumor model assays showed that the ds-Diabody against FGF-2 had potent antitumor activity in nude mice by inhibiting tumor growth and angiogenesis. The tumor growth inhibition rate of melanoma and glioma was about 70 and 45%, respectively. The tumor angiogenesis inhibition rate of melanoma and glioma was about 64 and 51%, respectively. The results revealed that the recombinant ds-Diabody against FGF-2 may be a promising anti-tumor drug for cancer therapy.

Large-scale production, purification, and function of a tumor multi-epitope vaccine: Peptibody with bFGF/VEGFA.

In tumor tissue, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor A (VEGFA) promote tumorigenesis by activating angiogenesis, but targeting single factor may produce drug resistance and compensatory angiogenesis. The Peptibody with bFGF/VEGFA was designed to simultaneously blockade these two factors. We were aiming to produce this Fc fusion protein in a large scale. The biological characterizations of Peptibody strains were identified as Escherichia coli and the fermentation mode was optimized in the shake flasks and 10-L bioreactor. The fermentation was scaled up to 100 L, with wet cell weight (WCW) 126 g/L, production 1.41 g/L, and productivity 0.35 g/(L·h) of IPTG induction. The target protein was isolated by cation-exchange, hydrophobic and Protein A chromatography, with total recovery of 60.28% and HPLC purity of 86.71%. The host cells protein, DNA, and endotoxin residues were within the threshold. In mouse model, immunization of Peptibody vaccine could significantly suppressed the tumor growth and angiogenesis, with inhibition rate of 57.73 and 39.34%. The Peptibody vaccine could elicit high-titer anti-bFGF and anti-VEGFA antibodies, which inhibited the proliferation and migration of Lewis lung cancer cell cells by decreasing the Akt/MAPK signal pathways. Therefore, the Peptibody with bFGF/VEGFA might be used as a therapeutic tumor vaccine. The large-scale process we developed could support its industrial production and pre-clinical study in the future.

miR-6086 inhibits ovarian cancer angiogenesis by downregulating the OC2/VEGFA/EGFL6 axis.

miRNAs have emerged as a pivotal component of gene regulatory networks, mediating cytokines secretion, cell cycle, and differentiation regulation. However, how miRNAs collaborate with transcription factors and downstream effector proteins that determine the fate of ovarian cancer cells remains to be understood, especially regarding to mechanism of tumor angiogenesis regulation. Based on the qRT-PCR and IHC analysis, we found that miR-6086 was maintained a very low level both in ovarian cancer cell lines and tissues. Further, we identified OC2 and EGFL6 as the direct targets of miR-6086 by luciferase assay and we observed an inverse relationship between the expression of miR-6086 and the OC2/VEGFA/EGFL6 axis. The Western blotting analysis suggested that OC2 could directly upregulate VEGFA and indirectly up-regulate EGFL6 through VEGFA. Moreover, miR-6086 could indirectly downregulate VEGFA through OC2. In addition, miR-6086, siOC2 and siEGFL6 could negatively regulate the tumor growth and angiogenesis of ovarian cancer (Skov3) in the animal studies, with the inhibition rates of 77.07%, 69.89%, and 73.62%, respectively (**p < 0.01). Moreover, the tumor cell proliferation, migration, and invasion of ovarian cancer cell lines (Caov3 and Skov3) and vascular formation (HUVECs) were significantly suppressed in vitro, by decreasing the AKT/MAPK pathways (*p < 0.05). Taken together, our results reveal that miR-6086 can suppress the angiogenesis networks in ovarian cancer by down-regulating the OC2/VEGFA/EGFL6 axis, directly or indirectly, which may provide potential targets for tumor therapeutics.

EuNPs-mAb fluorescent probe based immunochromatographic strip for rapid and sensitive detection of porcine epidemic diarrhea virus.

Porcine epidemic diarrhea (PED), induced by porcine epidemic diarrhea virus (PEDV) causes acute diarrhea, vomiting, dehydration and high mortality in neonatal piglets, resulting in significant economic losses in the pig industries. In this study, an immunochromatographic assay (ICA) based on a EuNPs-mAb fluorescent probe was developed and optimized for rapid detection of PEDV. The limit of detection (LOD) of the ICA was 0.218 µg/mL (2.725 × 103 TCID50/mL) and its linear detection range was 0.03125-8 µg/mL (3.91 × 102-105 TCID50/mL). The ICA was also validated for the detection of PEDV in swine stool samples. 60 swine stool samples from southern China were analyzed by the ICA and RT-PCR, and the results showed that the coincidence rate of the ICA to RT-PCR was 86.67%, which was significantly higher than that of AuNPs based ICA. The ICA is sensitive and specific and can achieve on-site rapid detection of swine stool samples. Therefore, the ICA has a great potential for PED diagnosis and prevention.

A smartphone colorimetric reader integrated with an ambient light sensor and a 3D printed attachment for on-site detection of zearalenone.

Smartphone biosensors could be cost-effective, portable instruments to be used for the readout of liquid colorimetric assays. However, current reported smartphone colorimetric readers have relied on photos of liquid assays captured using a camera, and then analyzed using software programs. This approach results in a relatively low accuracy and low generality. In this work, we reported a novel smartphone colorimetric reader that has been integrated with an ambient light sensor and a 3D printed attachment for the readout of liquid colorimetric assays. The portable and low-cost ($0.15) reader utilized a simplified electronic and light path design. Furthermore, our reported smartphone colorimetric reader can be compatible with different smartphones. As a proof of principle, the utility of this device was demonstrated using it in conjunction with an enzyme-linked immunosorbent assay to detect zearalenone. Results were consistent with those obtained using a professional microplate reader. The developed smartphone colorimetric reader was capable of providing scalable, cost-effective, and accurate results for liquid colorimetric assays that related to clinical diagnoses, environment pollution, and food testing. Graphical abstract A novel smartphone colorimetric reader that has been integrated with an ambient light sensor and a 3D printed attachment for the readout of liquid colorimetric assays.

Differential protein analysis of serum exosomes post-intravenous immunoglobulin therapy in patients with Kawasaki disease.

BACKGROUND: Kawasaki disease, which is characterised by systemic vasculitides accompanied by acute fever, is regularly treated by intravenous immunoglobulin to avoid lesion formation in the coronary artery; however, the mechanism of intravenous immunoglobulin therapy is unclear. Hence, we aimed to analyse the global expression profile of serum exosomal proteins before and after administering intravenous immunoglobulin. METHODS: Two-dimensional electrophoresis coupled with mass spectrometry analysis was used to identify the differentially expressed proteome of serum exosomes in patients with Kawasaki disease before and after intravenous immunoglobulin therapy. RESULTS: Our analysis revealed 69 differential protein spots in the Kawasaki disease group with changes larger than 1.5-fold and 59 differential ones in patients after intravenous immunoglobulin therapy compared with the control group. Gene ontology analysis revealed that the acute-phase response disappeared, the functions of the complement system and innate immune response were enhanced, and the antibacterial humoral response pathway of corticosteroids and cardioprotection emerged after administration of intravenous immunoglobulin. Further, we showed that complement C3 and apolipoprotein A-IV levels increased before and decreased after intravenous immunoglobulin therapy and that the insulin-like growth factor-binding protein complex acid labile subunit displayed reverse alteration before and after intravenous immunoglobulin therapy. These observations might be potential indicators of intravenous immunoglobulin function. CONCLUSIONS: Our results show the differential proteomic profile of serum exosomes of patients with Kawasaki disease before and after intravenous immunoglobulin therapy, such as complement C3, apolipoprotein A-IV, and insulin-like growth factor-binding protein complex acid labile subunit. These results may be useful in the identification of markers for monitoring intravenous immunoglobulin therapy in patients with Kawasaki disease.

iTRAQ-based Quantitative Proteomics Study in Patients with Refractory Mycoplasma pneumoniae Pneumonia.

Mycoplasma pneumoniae (MP) is a leading cause of community-acquired pneumonia in children and young adults. Although MP pneumonia is usually benign and self-limited, in some cases it can develop into life-threating refractory MP pneumonia (RMPP). However, the pathogenesis of RMPP is poorly understood. The identification and characterization of proteins related to RMPP could provide a proof of principle to facilitate appropriate diagnostic and therapeutic strategies for treating paients with MP. In this study, we used a quantitative proteomic technique (iTRAQ) to analyze MP-related proteins in serum samples from 5 patients with RMPP, 5 patients with non-refractory MP pneumonia (NRMPP), and 5 healthy children. Functional classification, sub-cellular localization, and protein interaction network analysis were carried out based on protein annotation through evolutionary relationship (PANTHER) and Cytoscape analysis. A total of 260 differentially expressed proteins were identified in the RMPP and NRMPP groups. Compared to the control group, the NRMPP and RMPP groups showed 134 (70 up-regulated and 64 down-regulated) and 126 (63 up-regulated and 63 down-regulated) differentially expressed proteins, respectively. The complex functional classification and protein interaction network of the identified proteins reflected the complex pathogenesis of RMPP. Our study provides the first comprehensive proteome map of RMPP-related proteins from MP pneumonia. These profiles may be useful as part of a diagnostic panel, and the identified proteins provide new insights into the pathological mechanisms underlying RMPP.

Soluble production and function of vascular endothelial growth factor/basic fibroblast growth factor complex peptide.

Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are important proangiogenic factors in tumor procession. The autocrine and paracrine bFGF and the VEGF in tumor tissue can promote tumor angiogenesis, tumor growth, and metastasis. A VEGF/bFGF Complex Peptide (VBP3) was designed on the basis of epitope peptides from both VEGF and bFGF to elicit in vivo production of anti-bFGF and anti-VEGF antibodies. In this study, we reported on the production of recombinant VBP3 using high cell density fermentation. Fed-batch fermentation for recombinant VBP3 production was conducted, and the production procedure was optimized in a 10-L fermentor. The fraction of soluble VBP3 protein obtained reached 78% of total recombinant protein output under fed-batch fermentation. Purified recombinant VBP3 could inhibit tumor cell proliferation in vitro and stimulate C57BL/6 mice to produce high titer anti-VEGF and anti-bFGF antibodies in vivo. A melanoma-grafted mouse model and an immunohistochemistry assay showed that tumor growth and tumor angiogenesis were significantly inhibited in VBP3-vaccinated mice. These results demonstrated that soluble recombinant VBP3 could be produced by large-scale fermentation, and the product, with good immunogenicity, elicited production of high-titer anti-bFGF and anti-VEGF antibodies, which could be used as a therapeutic tumor vaccine to inhibit tumor angiogenesis and tumor growth.

[Preparation of monoclonal antibody against lung cancer and identification of its targeting antigen].

A mouse-anti-human monoclonal antibody was produced by using the membrane proteins of human lung carcinoma cell line A549 as the immunogen to generate monoclonal antibodies against lung carcinoma with the use of hybridoma techniques. McAb4E7 was prepared successfully. To identify its antigen, proteomic technologies such as two-dimenstional electrophoresis, western blotting and mass spectrometry were employed. The targeting antigen of McAb4E7 expressed positive in human lung cancer cell lines A549 and human hepatocarcinoma cell line HepG2, moreover, the expression of the antigen was stronger in A549 cells. Finally, we obtained one positive protein in A549 cell line that has strong affinity and specificity for McAb4E7, which was identified to be ATP synthase beta subunit. We identified ATP synthase beta subunit as the targeting antigen of lung carcinoma special monoclonal antibody McAb4E7.

Identification of ATP synthase beta subunit (ATPB) on the cell surface as a non-small cell lung cancer (NSCLC) associated antigen.

BACKGROUND: Antibody-based immunotherapy has achieved some success for cancer. But the main problem is that only a few tumor-associated antigens or therapeutic targets have been known to us so far. It is essential to identify more immunogenic antigens (especially cellular membrane markers) for tumor diagnosis and therapy. METHODS: The membrane proteins of lung adenocarcinoma cell line A549 were used to immunize the BALB/c mice. A monoclonal antibody 4E7 (McAb4E7) was produced with hybridoma technique. MTT cell proliferation assay was carried out to evaluate the inhibitory effect of McAb4E7 on A549 cells. Flow cytometric assay, immunohistochemistry, western blot and proteomic technologies based on 2-DE and mass spectrometry were employed to detect and identify the corresponding antigen of McAb4E7. RESULTS: The monoclonal antibody 4E7 (McAb4E7) specific against A549 cells was produced, which exhibited inhibitory effect on the proliferation of A549 cells. By the proteomic technologies, we identified that ATP synthase beta subunit (ATPB) was the corresponding antigen of McAb4E7. Then, flow cytometric analysis demonstrated the localization of the targeting antigen of McAb4E7 was on the A549 cells surface. Furthermore, immunohistochemistry showed that the antigen of McAb4E7 mainly aberrantly expressed in tumor cellular membrane in non-small cell lung cancer (NSCLC), but not in small cell lung cancer (SCLC). The rate of ectopic expressed ATPB in the cellular membrane in lung adenocarcinoma, squamous carcinoma and their adjacent nontumourous lung tissues was 71.88%, 66.67% and 25.81% respectively. CONCLUSION: In the present study, we identified that the ectopic ATPB in tumor cellular membrane was the non-small cell lung cancer (NSCLC) associated antigen. ATPB may be a potential biomarker and therapeutic target for the immunotherapy of NSCLC.

Preparation of biodegradable polycaprolactone/poly (ethylene glycol)/polycaprolactone (PCEC) nanoparticles.

Biodegradable polyetherester copolymer (PCL/PEG/PCL, PCEC) was synthesized by ring-opening polymerization of epsilon-caprolactone initiated by poly(ethylene glycol) (PEG). The PCEC nanoparticles were prepared by solvent diffusion method or w/o/w double emulsion method. The obtained particles' morphology was observed on scanning electron microscopy, and the particle size distribution was determined using Malvern laser particle sizer. Bovine serum albumin was used as the model water-soluble protein drug, which was successfully encapsulated in PCEC nanoparticles, the drug release behavior was studied in detail. The hydrolytic degradation behavior of the PCEC nanoparticles was also studied.

[Differentiation of erythroleukemia K562 cells induced by piperine].

BACKGROUND & OBJECTIVE: The most common haematological malignancy is leukaemia. Differentiation induction is considered as one of the effective therapies for leukemia. Piperine, an alkaloid extracted from piperaceae, has been reported to display a variety of pharmacological activities, including sedation, anti-inflammation and antitumor effects. This study was to investigate the effect of piperine on proliferation, differentiation and apoptosis of erythroleukemia K562 cells. METHODS: Inhibition of cell growth was determined by trypan blue exclusion test; cell cycle and cell apoptosis were analyzed by FACS; induction of cell differentiation was confirmed by morphological observation, nitroblue tetrazolium (NBT) reduction assay and measurements of CD33 and CD14 expressions. RESULTS: Piperine induced K562 cells to differentiate into macrophages/monocytes at 20 micromol/L or 40 micromol/L. After incubation with 40 mumol/L piperine for 3 d, the NBT reduction rate of K562 cells increased from (8.5+/-1.9)% to (76.7+/-5.3)%; after incubation with 20 mumol/L piperine for 3 d, the mean fluorescence intensity (MFI) of CD33 in K562 cells was decreased by 42.05% (P<0.01), whereas the MFI of CD14 was doubled (P<0.01). Piperine inhibited the proliferation of K562 cells in a dose-and time-dependent manner at a concentration of above 20 micromol/L. CONCLUSION: Piperine can induce K562 cells to differentiate into macrophages/monocytes.