Detection Of Surface Markers Research Articles

Human Blood Non-Classical/Classical Monocyte Cells Are Heterogeneously Presented in Severe COVID-19 and Correlate with Disease Activity

Introduction: COVID-19 is highly heterogeneous, ranging from cases with mild disease with an almost asymptomatic carrier to severe cases, in which the disease evolves rapidly. A better understanding of monocyte response during SARS-CoV-2 infection would highlight potential biomarkers and establish other possible approaches for severe cases. Methods: The study group consisted of 32 COVID-19 patients and 18 health controls from June 2023 to March 2024. The COVID-19 patients were further classified as mild and severe illnesses based on World Health Organization (WHO) criteria. For flow cytometric analysis, 50 µL of peripheral blood and 1 µL of specific monoclonal antibodies were added to each cytometric tube for surface marker detection. Results: Here, the promising finding was that the blood non-classical/classical monocyte (NC/CL) subset was skewed toward NChighCLlow and NClowCLhigh clusters among the severe COVID-19 patients. The NChighCLlow cluster in severe COVID-19 displayed a distinct clinical phenotype, implying a higher 7-day disease progression rate (p = 0.019) and a worse 28-day survival (p = 0.026). Moreover, the secretion of IL-1β and IFN-γ was primarily attributed to CL subset in monocytes, while IL-6 was secreted mainly by NC subset. Conclusion: As supported, regarding cytokine profile in context of SARS-CoV-2 infection, it was identified that circulating NC cells are proinflammatory cells most related to regulatory cells, while CL subset displayed an effective capacity to virus. These findings have implications toward optimizing evaluation in severe COVID-19, and developing strategies that target altered balance of NC/CL cell subsets.

Impacts of mesenchymal stem cells and hyaluronic acid on inflammatory indicators and antioxidant defense in experimental ankle osteoarthritis.

No effective treatment guarantees full recovery from osteoarthritis (OA), and few therapies have disadvantages. To determine if bone marrow mesenchymal stem cells (BMMSCs) and hyaluronic acid (HA) treat ankle OA in Wistar rats. BMMSCs were characterized using flow cytometry with detection of surface markers [cluster of differentiation 90 (CD90), CD105, CD34, and CD45]. Fifty male Wistar rats were divided into five groups of 10 rats each: Group I, saline into the right tibiotarsal joint for 2 days; Group II, monosodium iodate (MIA) into the same joint; Groups III, MIA + BMMSCs; Group IV, MIA + HA; and Group V, MIA + BMMSCs + HA. BMMSCs (1 × 106 cells/rat), HA (75 µg/rat), and BMMSCs (1 × 106 cells/rat) alongside HA (75 µg/rat) were injected intra-articularly into the tibiotarsal joint of the right hind leg at the end of weeks 2, 3, and 4 after the MIA injection. The elevated right hind leg circumference values in the paw and arthritis clinical score of osteoarthritic rats were significantly ameliorated at weeks 4, 5, and 6. Lipid peroxide significantly increased in the serum of osteoarthritic rats, whereas reduced serum glutathione and glutathione transferase levels were decreased. BMMSCs and HA significantly improved OA. The significantly elevated ankle matrix metalloproteinase 13 (MMP-13) mRNA and transforming growth factor beta 1 (TGF-β1) protein expression, and tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) serum levels in osteoarthritic rats were significantly downregulated by BMMSCs and HA. The effects of BMMSCs and HA on serum TNF-α and IL-17 were more potent than their combination. The lowered serum IL-4 levels in osteoarthritic rats were significantly upregulated by BMMSCs and HA. Additionally, BMMSCs and HA caused a steady decrease in joint injury and cartilage degradation. BMMSCs and/or HA have anti-arthritic effects mediated by antioxidant and anti-inflammatory effects on MIA-induced OA. MMP-13 and TGF-β1 expression improves BMMSCs and/or HA effects on OA in Wistar rats.

Abstract A030: Rapid extraction and detection of extracellular vesicle-derived PD-L1 in a microfluidic platform

Abstract Background. Extracellular vesicles (EV) are emerging as new biomarkers for cancer diagnostics and therapeutic monitoring1. For example, in patients that receive PD1/PD-L1 immune checkpoint inhibitors (a key pillar of cancer immunotherapy), circulating EV-derived PD-L1 is gaining attention as a non-invasive biomarker for therapeutic efficacy. Standard methodologies to measure EV-derived PD-L1 requires ultracentrifugation to first separate EVs and then quantify those that express PD-L1 using nano flow cytometry. These are tedious processes that require trained technologists in centralized facilities, which is a key barrier to frequently monitoring EV-based biomarkers. Yet, frequent monitoring is crucial to quickly identify and stop an ineffective therapy while more fruitful options are still available. Method. To bridge the gap, we develop a proof-of-concept digital microfluidic (DMF) device that can separate EVs directly from biofluids and quantify PD-L1+ EVs automatedly. Briefly, DMF device supports automatedly droplet handling, including droplet transport, splitting and mixing, based on electrowetting principles2. Immunomagnetic beads were used to capture EVs from biofluids, and EVs were then detected by electrochemical sensors inserted into the device. These tips of the electrochemical sensors were modified with gold nanoparticle self-assembled layers to enhance target binding, and CD9 antibodies were immobilized on the tips to bind to EVs. We then used anti-PD-L1 as secondary antibodies for target detection. Differential Pulse Voltammetry (DPV)3 were performed to obtain the results. Results. We used the DMF device to extract 109- 1011 #/mL EVs secreted by a human breast cancer cell line (MDA-MB-231). Briefly, 10 mL of cell culture media was loaded into the DMF device, and the sample was mixed and incubated with a 10 mL droplet of immunomagnetic beads to capture EVs. After 5 min, EVs were eluted in 20 mL of elution buffer, and the beads were discarded. We estimated the number of EVs using Nanoparticle Tracking Analysis; the number of EVs extracted on-chip was comparable with those that were extracted using standard in-tube method. We also verified the purity of the EVs extracted on-chip using Western Blot. Our results showed that the electrochemical sensors can detect as low as 104 #/mL PD-L1+ EVs, with a linear range of 104 – 107 #/mL (R2=0.9701). The entire process can be completed within 1 hour. Conclusion. We integrated automated EV extraction and their surface marker detection in a single DMF device. Our next step is to extract and detect EV-based biomarkers from plasma samples. This platform holds promise for the regular monitoring of EV-based biomarkers that are indicators of therapeutic responses in patients that receive cancer immunotherapies.

Lysis of Extracellular Vesicles and Multiplexed Protein Detection via a Reverse Phase Immunoassay Using a Gold-Nanoparticle-Embedded Membrane Platform.

Extracellular vesicles (EVs) are cell-derived membrane-bound particles with molecular cargo reflective of their cell of origin. Analysis of disease-related EVs and associated cargo from biofluids is a promising tool for disease management. To facilitate the analysis of intravesicular molecules, EV lysis is needed. Moreover, highly sensitive and multiplexed detection methods are required to achieve early diagnostics. While cell lysis approaches have been well studied, the analysis of EV lysis methods and their effects on downstream molecular detection is lacking. In this work, we analyzed chemical, thermal, and mechanical EV lysis methods and determined their efficiency based on EV particle concentration and immunoassay activity. We, for the first time, discovered that vortex was an efficient EV lysis method and used it for detection of surface and intravesicular markers in a highly sensitive multiplexed reverse phase immunoassay on a gold-nanoparticle-embedded membrane. In phosphate-buffered saline, detection limits up to 3 orders of magnitude lower than enzyme-linked immunosorbent assay were achieved. In spiked human plasma, detection limits as low as 7.27 × 104 EVs/mL were achieved, making it suitable for early diagnostics. These results demonstrated an effective pipeline for lysing and molecular analysis of EVs from complex biofluids, paving the way for their broad applications in biomedicine.

Development of a T-cell activation panel using image cytometry in rheumatoid arthritis patient samples

Abstract Rheumatoid arthritis (RA) is an autoimmune disease that results in cartilage damage and bone loss due to chronic inflammation of joints. Treatments for RA include disease-modifying antirheumatic drugs and nonsteroidal anti-inflammatory drugs, as well as the inhibition of activated T-cells. Consequently, there is a need to screen RA patient samples rapidly and effectively to monitor treatment efficacy, disease progression, immune response, and predictive markers. In this work, we developed and demonstrated a multiplex detection method to monitor T-cell activation in a panel consisting of CD3, CD69, CD25, and CD279 (PD-1) surface markers using the Cellaca™ PLX Image Cytometer (Revvity). First, a dosage titration of PHA-P was performed on PBMCs to stimulate T-cell activation. Once stimulated, CD3 positive T-cells were evaluated for CD69, CD25, and the checkpoint molecule CD279. After 24 hours, the percent surface marker positive T-cells and the level of marker expression (median fluorescent intensity values) were used to determine optimal PHA-P dosage. Results showed concentration dependent increases in the expression levels with a calculated EC50 value for PHA-P ranging from 20.16-30.78 µg/mL with a 95% CV based on the CD279 titration curve. The proposed image cytometric surface marker detection method may prove to be an efficient tool to rapidly screen RA patient samples for T-cell activation in the setting of clinical disease treatment or progression.

Identification of Intestinal Lamina Propria Plasma Cells by Surface Transmembrane Activator and CAML Interactor Expression.

Plasma cells secrete an abundance of Abs and are a crucial component of our immune system. The intestinal lamina propria harbors the largest population of plasma cells, most of which produce IgA. These Abs can bind to beneficial gut bacteria to reinforce intestinal homeostasis and provide protection against enteric pathogens. Plasma cells downregulate many cell-surface proteins commonly used to identify B cells. In mice, expression of the surface marker CD138 has been widely used to identify plasma cells in lymph nodes, bone marrow, and spleen. Intestinal plasma cells require liberation via extensive tissue processing involving treatment with collagenase. We report that detection of CD138 surface expression is reduced following collagenase treatment. Using a mouse in which yellow fluorescent protein expression is controlled by the plasma cell requisite transcription factor Blimp-1, we show that surface detection of transmembrane activator and CAML interactor captures a significant proportion of Ab-secreting plasma cells in the intestinal lamina propria and gut-draining mesenteric lymph nodes. Additionally, we describe a flow cytometry panel based on the detection of surface markers to identify murine B cell subsets in the intestinal lamina propria and, as a proof of concept, combine it with a cutting-edge fate-tracking system to characterize the fate of germinal center B cells activated in early life. By identifying plasma cells and other key intestinal B subsets in a manner compatible with several downstream applications, including sorting and culturing and invitro manipulations, this efficient and powerful approach can enhance studies of mucosal immunity.

Cellaca® PLX image cytometer as an alternative for immunophenotyping, GFP/RFP transfection efficiencies, and apoptosis analysis

Cell and gene therapy is a fast-growing field for cancer therapeutics requiring reliable instrumentation and technologies. Key parameters essential for satisfying Chemistry Manufacturing and Controls criteria standards are routinely performed using flow cytometry. Recently, image cytometry was developed for cell characterization and cell-based assays but had not yet demonstrated sufficient sensitivity for surface marker detection. We developed the Cellaca® PLX image cytometry system and the respective methodologies required for immunophenotyping, GFP and RFP transfection/transduction efficiencies, and cell health analyses for routine cell characterization. All samples tested were compared directly to results from the CytoFLEX flow cytometer. PBMCs were stained with T-cell surface markers for immunophenotyping, and results show highly comparable CD3, CD4, and CD8 populations (within 5 %). GFP- or RFP-expressing cell lines were analyzed for transfection/transduction efficiencies, and the percentage positive cells and respective viabilities were equivalent on both systems. Staurosporine-treated Jurkat cells were stained for apoptotic markers, where annexin V and caspase-3 positive cells were within 5 % comparing both instruments. The proposed system may provide a complementary tool for performing routine cell-based experiments with improved efficiency and sensitivity compared to prior image cytometers, which may be significantly valuable to the cell and gene therapy field.

Predominantly Pro-Inflammatory Phenotype with Mixed M1/M2 Polarization of Peripheral Blood Classical Monocytes and Monocyte-Derived Macrophages among Patients with Excessive Ethanol Intake.

Excessive alcohol consumption impairs the immune system, induces oxidative stress, and triggers the activation of peripheral blood (PB) monocytes, thereby contributing to alcoholic liver disease (ALD). We analyzed the M1/M2 phenotypes of circulating classical monocytes and macrophage-derived monocytes (MDMs) in excessive alcohol drinkers (EADs). PB samples from 20 EADs and 22 healthy controls were collected for isolation of CD14+ monocytes and short-term culture with LPS/IFNγ, IL4/IL13, or without stimulation. These conditions were also used to polarize MDMs into M1, M2, or M0 phenotypes. Cytokine production was assessed in the blood and culture supernatants. M1/M2-related markers were analyzed using mRNA expression and surface marker detection. Additionally, the miRNA profile of CD14+ monocytes was analyzed. PB samples from EADs exhibited increased levels of pro-inflammatory cytokines. Following short-term culture, unstimulated blood samples from EADs showed higher levels of soluble TNF-α and IL-8, whereas monocytes expressed increased levels of surface TNF-α and elevated mRNA expression of pro-inflammatory cytokines and inducible nitric oxide synthase. MDMs from EADs showed higher levels of TNF-α and CD206 surface markers and increased IL-10 production. LPS/IFNγ induced higher mRNA expression of Nrf2 only in the controls. miRNA analysis revealed a distinctive miRNA profile that is potentially associated with liver carcinogenesis and ALD through inflammation and oxidative stress. This study confirms the predominantly pro-inflammatory profile of PB monocytes among EADs and suggests immune exhaustion features in MDMs.

A 47-marker immune profiling flow cytometry assay to enable comprehensive antigen-specific immune analysis

Abstract The complex nature of the immune system requires deep interrogation at the single-cell level. Flow cytometry using CyTOF® technology employs antibodies tagged with isotopically enriched metals instead of fluorophores, resulting in discrete signals that facilitate highly multiparametric characterization on a single-cell level. CyTOF technology enables analysis of over 50 parameters simultaneously without the impediments of spectral overlap or autofluorescence, allowing for a reliable evaluation of immune responses. The Maxpar® Direct™ Immune Profiling Assay™ is a pre-titrated, dried-down, and validated 30-marker antibody cocktail for single-tube staining of human whole blood or PBMC and acquisition on CyTOF systems. Using the assay and Maxpar Pathsetter™ software, stained samples are automatically resolved into 37 immune populations. In this study, we highlight the customizability of the Maxpar® Direct panel by adding an array of 17 surface and intracellular parameters with the Maxpar Direct™ T Cell Activation Expansion Panel and live-cell barcoding. The simultaneous detection of key surface and intracellular markers in this expanded panel enabled comprehensive analysis of immune cell activation and antigen-specific recall responses to PBMC stimulated with a pool of immunodominant microbial peptides. Taken together, this 47-marker panel and automated analysis unlocked deeper immunophenotyping and functional profiling of activated immune cells and provided insight into the cell-mediated adaptive immune response to foreign targets. Such phenomena are hallmarks for research on infection, vaccine development, and immunotherapy. For Research Use Only. Not for use in diagnostic procedures.

Cell identity, count, and viability for critical quality attributes using the Cellaca PLX image cytometer

Abstract Cell and gene therapy is one of the fastest growing fields for cancer therapeutics that heavily relies on robust and consistent instrumentations and technologies to verify and validate the fit-for-purpose critical quality attributes (CQA). Some of the key parameters required for satisfying CMC (Chemistry Manufacturing and Controls) criteria standards for cellular therapeutic products are routinely performed using flow cytometry. In the past decade, image cytometry was developed for cell characterization and cell-based assays but had not yet demonstrated the sensitivity required for surface marker detection. We demonstrate the capability of the Cellaca PLX image cytometry system for surface marker population analysis, GFP and RFP cell viability, and cell health in comparison to flow cytometry. For immunophenotyping, PBMCs were stained with Hoechst/CD3/CD4/CD8, and viability detection of GFP and RFP-containing cell lines was performed by staining with Hoechst/RubyDead. Additionally, apoptosis was induced in Jurkat cells with staurosporine and cells stained with Hoechst/Caspase 3-488/RubyDead. All assays were analyzed on the Cellaca PLX and compared directly to the CytoFLEX. Results show similar surface marker populations: CD3 (76% and 81%, PLX and CytoFLEX, respectively), CD4 (43% and 42%), and CD8 (15% and 17%). Viabilities of RFP and GFP cells were equivalent on both platforms, and population percentages of Hoechst/Caspase 3/RubyDead positive cells were within 5% of each other. Our experiments demonstrate that the Cellaca PLX image cytometer can be of significant value to the Cell and Gene Therapy communities to satisfy several CMC criteria including high-throughput, high sensitivity, and low maintenance.

Small extracellular vesicles have distinct CD81 and CD9 tetraspanin expression profiles in plasma from rheumatoid arthritis patients.

Extracellular vesicles (EVs) are implicated in the pathogenesis of rheumatoid arthritis (RA) but little is known about the composition of specific small EV (sEV) subpopulations. This study aimed to characterize the CD63, CD81 and CD9 tetraspanin profile in the membrane of single EVs in plasma from treatment naïve RA patients and assess potential discrepancies between methotrexate (MTX) responder groups. EVs isolated from plasma were characterized using transmission electron microscopy, and detection of surface markers (CD63, CD81 and CD9) on single EVs was performed on the ExoView platform. All RA patients (N = 8) were newly diagnosed, treatment naïve, females, ACPA positive and former smokers. The controls (N = 5) were matched for age and gender. After three months of MTX treatment, responders (N = 4) were defined as those with ΔDAS28 > 1.2 and DAS28 ≤ 3.2 post-treatment. The isolated EVs were 50-200nm in size. The RA patients had a higher proportion of both CD9 and CD81 single positive sEVs compared to healthy controls, while there was a decrease in CD81/CD9 double positive sEVs in patients. Stratification of RA patients into MTXresponders and non-responders revealed a distinctly higher proportion of CD81 single positive sEVs in the responder group. The proportion of CD81/CD9 double positive sEVs (anti-CD9 captured) was lower in the non-responders, but increased upon 3months of MTXtreatment. Our exploratory study revealed distinct tetraspanin profiles in RA patients suggesting their implication in RA pathophysiology and MTX treatment response.

LncRNA MEG3 induces endothelial differentiation of mouse derived adipose-derived stem cells by targeting MiR-145-5p/KLF4

The present study aimed to investigate the mechanisms through which long non-coding RNA (lncRNA) maternally expressed 3 (MEG3) affected the endothelial differentiation of mouse derived adipose-derived stem cells (ADSCs). ADSCs were isolated and identified by specific surface marker detection. The effects of lncRNA MEG3 on endothelial differentiation of ADSCs were also detected via quantitative PCR, western blotting, immunofluorescence and Matrigel angiogenesis assays. In addition, using target gene prediction tools and luciferase reporter assays, the downstream target gene was demonstrated. LncRNA MEG3 targeted and reduced the expression levels of microRNA-145-5p (miR-145-5p), which upregulated the expression levels of Krüppel like factor 4 (KLF4), promoting endothelial differentiation of ADSCs. LncRNA MEG3 induced endothelial differentiation of ADSCs by targeting miR-145-5p/KLF4, which may provide novel insights to illustrate the mechanism of endothelial differentiation of ADSCs.

Ricolinostat promotes the generation of megakaryocyte progenitors from human hematopoietic stem and progenitor cells

BackgroundEx vivo production of induced megakaryocytes (MKs) and platelets from stem cells is an alternative approach for supplying transfusible platelets. However, it is difficult to generate large numbers of MKs and platelets from hematopoietic stem cells and progenitor cells (HSPCs).MethodsTo optimize the differentiation efficiency of megakaryocytic cells from HSPCs, we first employed a platelet factor 4 (PF4)-promoter reporter and high-throughput screening strategy to screen for small molecules. We also investigated the effects and possible mechanisms of candidate small molecules on megakaryocytic differentiation of human HSPCs.ResultsThe small molecule Ricolinostat remarkably promoted the expression of PF4-promoter reporter in the megakaryocytic cell line. Notably, Ricolinostat significantly enhanced the cell fate commitment of MK progenitors (MkPs) from cord blood HSPCs and promoted the proliferation of MkPs based on cell surface marker detection, colony-forming unit-MK assay, and quantitative real-time PCR analyses. MkPs generated from Ricolinostat-induced HSPCs differentiated into mature MKs and platelets. Mechanistically, we found that Ricolinostat enhanced MkP fate mainly by inhibiting the secretion of IL-8 and decreasing the expression of the IL-8 receptor CXCR2.ConclusionThe addition of Ricolinostat to the culture medium promoted MkP differentiation from HSPCs and enhanced the proliferation of MkPs mainly by suppressing the IL-8/CXCR2 pathway. Our results can help the development of manufacturing protocols for the efficient generation of MKs and platelets from stem cells in vitro.

Macrophage polarization induced by quinolone antibiotics at environmental residue level

Widespread use of quinolone antibiotics leads to serious residues in the environment and toxicity effects. This paper studied the effects of three typical quinolone antibiotics ciprofloxacin, norfloxacin and pipemidic acid on the polarization of macrophages RAW264.7 cells. The experimental concentrations were 0.01, 0.1, 1, 10, 100 and 1000 μg/L according to the environmental residual level. By MTT assay, phagocytosis assay and migration assay, macrophages were found to exhibit hormesis effect of low dose promotion and high dose inhibition. The detection of macrophages surface markers showed that 0.1 μg/L antibiotics increased the secretion of pro-inflammatory cytokines and induced macrophages to be M1-type, and 1000 μg/L antibiotics significantly increased the secretion of anti-inflammatory cytokines and induced macrophages to be M2-type. In order to explore the relationship between low-dose excitatory effects and polarization, the mechanism of 0.1 μg/L antibiotics inducing macrophages to M1-type was further studied. Results showed that 0.1 μg/L quinolone antibiotics activated the key proteins in the PI3K/Akt, Notch1, JNK and JAK2/STAT3 signaling pathways to cause the secretion of pro-inflammatory cytokines and induce inflammation. In order to eliminate inflammation, macrophages number feedback increased, phagocytosis and migration function enhanced, showing hormesis effect. In vitro macrophages experiment confirmed that quinolone antibiotics with environmental residual concentration had immunotoxicity.

MiRNA-130 Promotes Migration and Angiogenesis of Endothelial Progenitor Cells Through PI3K/AKT/mTOR Pathways

<sec> <title>Aim:</title> In this study, we aimed to investigate the effects and mechanisms of miRNA-130a in human endothelial progenitor cells (EPCs) involved in Deep vein thrombosis (DVT). </sec> <sec> <title>Methods:</title> EPCs were isolated and identified by cell morphology and surface marker detection. The effect of miR-130a on the migration, invasion and angiogenesis of EPCs in vitro were also detected. In addition, whether miR-130a is involved in the MMP-1 expression and Akt/PI3K/mTOR signaling pathway was also demonstrated. </sec> <sec> <title>Results:</title> Results suggested that miRNA-130a promotes migration, invasion, and tube formation of EPCs by positively regulating the expression of MMP-1 through Akt/PI3K/mTOR signaling pathway. </sec> <sec> <title>Conclusion:</title> Thus, as a potential therapeutic target, miRNA-130a may play an important role in the treatment of DVT. </sec>

Proximity hybridization-mediated fluorescence resonance energy transfer for highly specific detection of tumor-derived exosomes: Combining multiple exosomal surface markers

Highly specific detection of tumor-derived exosomes is of great significance to improve the accuracy of diagnosis of cancer. Herein, based on the proximity hybridization-mediated fluorescence resonance energy transfer (FRET), a novel strategy for highly specific detection of tumor-derived exosomes was proposed by combining detection of multiple exosomal surface markers. Exosomes were enriched and separated by CD63 aptamer-functionalized nanomagnetic beads; a pair of FAM-labeled proximity probes simultaneously bind to EGFR and EpCAM on exosomes surface, which could mediate the formation of a stable DNA self-assemble complex with TAMRA-labeled signal probes through proximity hybridization, and then trigger the FRET between FAM and TAMRA to achieve highly specific detection of exosomes co-expressed CD63/EGFR/EpCAM with a LOD of 400 particles/μL. The relative standard deviation was lower than 7.3% in 50% UC-FBS due to the ratiometric signal improving its anti-interference ability. Importantly, in addition to effectively distinguish exosomes derived from A549 cells and BEAS-2B cells, the feasibility of exosomes detection in human serum was verified, and the level of exosomes co-expressed CD63/EGFR/EpCAM in non-small cell lung cancer patients (n = 15) was significantly higher than that of healthy people (n = 15) (P < 0.001). Moreover, this strategy was universal for the detection of other tumor-derived exosomes just by replacing the corresponding aptamers.

Combined Measurement of RNA and Protein Expression on a Single-Cell Level.

Single-cell RNA sequencing (sc-RNAseq) has become a critical approach for the analysis of immune cell function and heterogeneity. So far, the immune cell isolation, based on surface marker expression predicted by the RNA expression profiles, is often limited by the poor correlation between transcript and protein expression patterns. To overcome these difficulties, novel single-cell multi-omic approaches based on the combined analysis of transcript and surface protein expression have been developed. One of the major benefits of these technologies is the possibility to use a high number of antibodies conjugated with oligonucleotide (AbOs) for the surface marker detection, thus overcoming the limit of using few surface markers as occurs in flow cytometry. Here we describe the BD Rhapsody single-cell analysis system protocol for 3' mRNA whole transcriptome analysis (WTA), combined with AbO- and Sample Tag library preparation.

Allogeneic tumor cell line-based vaccines: A good alternative to autologous and cancer stem cell vaccines in colorectal cancer.

Objective(s):Besides the uncertainty about colorectal cancer stem cell (CCSC) markers, isolating, purifying, and enriching CCSCs to produce CCSC vaccines is highly challenging. However, allogeneic vaccines developed from CRC cell lines can provide universal, comprehensive, inexpensive, simple, and fast approach to cancer treatment. Materials and Methods:CCSCs were isolated from human CRC tissue using the in vitro sphere formation assay and then characterized through gene expression analysis, in vivo and in vitro tumor formation assay, karyotyping, and surface marker detection. Subsequently, CCSCs and two CRC cell lines (HT-29 and SW-480) were inactivated with cisplatin (CDDP) and administrated as vaccines to the three groups of athymic C57BL/6 nude mice. Afterward, tumorigenesis was challenged with HT-29 cells. The antitumor effect of vaccines was evaluated by tumor and spleen examination and immune response analysis. The cytotoxic activity of splenocytes and serum levels of TGF-β and IFN-γ were measured by Calcein-AM cytotoxicity assay and enzyme-linked immunosorbent assay (ELISA), respectively.Results:The results of gene expression analysis showed that CCSCs are CD44+CD133-LGR5-. All vaccinations resulted in decreased tumor growth, spleen enlargement, enhanced serum level of IFN-γ and TGF-β, and increased cytotoxic activity of natural killer (NK) cells. The antitumor efficacy of the CCSC vaccine was not more than CRC cell line-based vaccines. Interestingly, the allogeneic SW-480 vaccine could effectively inhibit tumorigenesis.Conclusion:Despite the great challenge in developing CCSC vaccines, allogeneic vaccines based on CRC cell lines can efficiently induce antitumor immunity in CRC.

Multiplexed electrokinetic sensor for detection and therapy monitoring of extracellular vesicles from liquid biopsies of non-small-cell lung cancer patients

Liquid biopsies based on extracellular vesicles (EVs) represent a promising tool for treatment monitoring of tumors, including non-small-cell lung cancers (NSCLC). In this study, we report on a multiplexed electrokinetic sensor for surface protein profiling of EVs from clinical samples. The method detects the difference in the streaming current generated by EV binding to the surface of a functionalized microcapillary, thereby estimating the expression level of a marker. Using multiple microchannels functionalized with different antibodies in a parallel fluidic connection, we first demonstrate the capacity for simultaneous detection of multiple surface markers in small EVs (sEVs) from NSCLC cells. To investigate the prospects of liquid biopsies based on EVs, we then apply the method to profile sEVs isolated from the pleural effusion (PE) fluids of five NSCLC patients with different genomic alterations (ALK, KRAS or EGFR) and applied treatments (chemotherapy, EGFR- or ALK-tyrosine kinase inhibitors). The vesicles were targeted against CD9, as well as EGFR and PD-L1, two treatment targets in NSCLC. The electrokinetic signals show detection of these markers on sEVs, highlighting distinct interpatient differences, e.g., increased EGFR levels in sEVs from a patient with EGFR mutation as compared to an ALK-fusion one. The sensors also detect differences in PD-L1 expressions. The analysis of sEVs from a patient prior and post ALK-TKI crizotinib treatment reveals significant increases in the expressions of some markers (EGFR and PD-L1). These results hold promise for the application of the method for tumor treatment monitoring based on sEVs from patient liquid biopsies.

Macrophage retrieval from 3D biomaterials: A detailed comparison of common dissociation methods

IntroductionThe immune system is widely recognized as a crucial determinant in implant biocompatibility and tissue integration. In order to assess macrophage response to biomaterials, commonly used analysis techniques require the removal of cells from the material. This process inherently has a negative impact on the cells, but few studies have comprehensively compared different dissociation methods in terms of impact on cell yield, viability, phenotype and function. MethodsCell scraping, EDTA at 4 °C, EDTA at 37 °C, trypsin, Accutase and the PromoCell macrophage detachment solution were compared in terms of cell yield and viability. The effect of Accutase on cell surface antigen conservancy and cell functionality was investigated. Lastly, effect of Accutase detachment of macrophages from electrospun biomaterials was analyzed. ResultsThe efficiency of common cell detachment protocols for human monocyte-derived macrophages (MDMs) varies significantly between enzymatic and non-enzymatic approaches. In terms of surface marker detection, we showed that enzymatic detachment not only selectively cleaves the M2 markers CD206 and CD163, but we also identified that this effect is variable across donors. Furthermore, we observed that the process of cell detachment impairs macrophage endocytic ability. Lastly, we tested the efficiency of enzymatic cell detachment on electrospun 3D matrices designed for tissue engineering. ConclusionOur results provide a thorough understanding of the advantages and disadvantages of commonly used cell dissociation methods and have important implications for studies investigating the macrophage response to biomaterials.