Enriching new transplantable RGC-like cells from retinal organoids for RGC replacement therapy

Optic neuropathies, such as glaucoma, are due to progressive retinal ganglion cells (RGCs) degeneration, result in irreversible vision loss. The promising RGCs replacement therapy for restoring vision are impeded by insufficient RGC-like cells sources. The present work was enriched one new type RGC-like cells using two surface markers CD184 and CD171 from human induced pluripotent stem cells (hiPSCs) by FACS sorting firstly. These new kind cells have well proliferation ability and possessed passage tolerance in vitro 2D or 3D spheroids culture, which kept expressing Pax6, Brn3b and βIII-Tubulin and so on. The transplanted CD184+CD171+ RGC-like cells could survive and integrate into the normal and optic nerve crush (ONC) mice retina, especially they were more inclined to across the optic nerve head and extend to the damaged optic nerve. These data support the feasible application for cell replacement therapy in RGC degenerative diseases, as well as help to develop new commercial cells sorting reagents and establish good manufacturing practice (GMP) grade RGC-like donor cells for further clinical application.

Lectin: A Molecular Tool in Cancer Diagnosis and Therapy with Special Reference to Reproductive Cancers

The prevalence of cancer deaths globally and domestically is higher especially due to the deferment of diagnosis and lack of facilities for women's reproductive cancers. The present review focussed to explore the application of lectins in cancer theranostics. Though there is cancer diagnostic and treatment available there is no promising early diagnostic tool and effective treatment available for the cancer which is the major concern. Lectins are cellulose-binding proteins that are strongly determined in saccharide groups of glycans, glycopeptides, or glycolipids. In the concomitance of events in cells, carbohydrates, and proteins, lectins play an important role. Lectins bind superiorly to the cancer cell membrane and their receptors induce the cytotoxic effect, which results in caspase-mediated cell death, and prohibits tumour development. Lectin snuffing also reveals polyamine stocks and impedes the growth of cancerous cells. They affect the cell cycle by non-apoptotic aggregation, seizure of the cell cycle phase G2, M, and the mediation of caspases. It can also adversely affect the action of telomerase and hinder vascularisation. They promote immunomodulation and adversely limit protein synthesis. Their easy availability and its characteristics support its use in cancer diagnosis and therapy, despite their small corollary effects. Future investigations recommend focussing more on the key applications of lectin by reducing its concurrent effects and carrying out more in-vitro investigations. However, the use of lectin formulations for cancer theranostics is a new area in cancer detection and treatment. In this review, plant lectin appears to be a potential target for cancer research in the fields of diagnosis and theranostics.

Expression of stem cell markers as predictors of therapeutic response in metastatic prostate cancer patients

BACKGROUND

Cancer stem cells (CSCs) have been implicated in prostate cancer (PCA) progression and therapeutic resistance. This study aimed to compare the expression levels of CSC CD (CD 44, CD 133, and CD 24) markers in treatment-naive patients with metastatic PCA before and after treatment.

METHODS

The study included 60 treatment-naïve patients with metastatic PCA who received androgen deprivation therapy (ADT) alone (n = 30) and ADT plus chemotherapy (n = 30). The level of CD44, CD133, and CD24 were obtained by flow cytometric analysis before and after treatment. Baseline characteristics were also assessed, including age, pretreatment testosterone levels, and pretreatment prostate-specific antigen (PSA) levels.

RESULTS

The baseline characteristics analysis showed no significant difference in pre-treatment testosterone levels between the ADT+ chemotherapy and ADT-alone groups. In the flow cytometric analysis, no significant difference was observed in pre-treatment CD44+ and CD133+ levels between the 2 treatment groups, although a trend towards higher pretreatment CD24- levels was observed in the ADT+ chemotherapy group. After treatment, significant reductions in testosterone and PSA levels were observed in both treatment arms. The ADT+ chemotherapy group showed a greater reduction in CD44+ and CD133+ levels compared to the ADT-alone group. Bioinformatic analysis using the UALCAN TCGA database also showed a similar trend of CD 44, CD 24, and CD 133 gene expression patterns.

CONCLUSION

Combination therapy involving chemotherapy and ADT appears to have a greater impact on suppressing CSCs compared to ADT alone. These findings highlight the potential of targeting CSCs as a prognostic and predictive marker therapeutic strategy in metastatic PCA.

Innate lymphoid cells (ILCs) in teleosts against data on ILCs in humans

It is assumed that cells corresponding to innate lymphoid cells (ILCs) in humans, in addition to lymphoid tissue inducer cells (LTi), are also found in teleosts. In this systematic group of organisms, however, they are a poorly understood cell population. In contrast to the data on ILCs in humans, which also remain incomplete despite advanced research, in teleosts, these cells require much more attention. ILCs in teleosts have been presented as cells that may be evolutionary precursors of NK cells or ILCs identified in mammals, including humans. It is a highly heterogeneous group of cells in both humans and fish and their properties, as revealed by studies in humans, are most likely to remain strictly dependent on the location of these cells and the physiological state of the individual from which they originate. They form a bridge between innate and adaptive immunity. The premise of this paper is to review the current knowledge of ILCs in teleosts, taking into account data on similar cells in humans. A review of the knowledge concerning these particular cells, elements of innate immunity mechanisms as equivalent to, or perhaps dominant over, adaptive immunity mechanisms in teleosts, as presented, may inspire the need for further research.

Primary Human Leukemia Stem Cell (LSC) Isolation and Characterization

Leukemia stem cells (LSC) are thought to be the basis of leukemia progression since they are highly resistant to conventional chemotherapy. LSC isolation is critical in experimental studies, drug development, and application. Due to their likely hematopoietic stem cell (HSC) origin, LSCs have surface antigens that are similar to HSC. Surface markers such as CD34, CD123, CD133, and CD33 have been used extensively to assess LSCs. LSCs could be separated from other cells using magnetic selection (MS) or flow cytometry selection (FCS) methods using these markers. Understanding the role of LSCs in cancer progression and how to therapeutically target them in vitro and in vivo is critical for the development of LSC-targeting drug candidates. In this chapter, we set out to describe the primary human LSC purification and characterization processes used on patient samples with leukemia and lymphoma.

Comprehensive characterization of pathogenic synovial fluid extracellular vesicles from knee osteoarthritis

Synovial fluid (SF) extracellular vesicles (EVs) play a pathogenic role in osteoarthritis (OA). However, the surface markers, cell and tissue origins, and effectors of these EVs are largely unknown. We found that SF EVs contained 692 peptides that were positively associated with knee radiographic OA severity; 57.4% of these pathogenic peptides were from 46 proteins of the immune system, predominantly the innate immune system. CSPG4, BGN, NRP1, and CD109 are the major surface markers of pathogenic SF EVs. Genes encoding surface marker CSPG4 and CD109 were highly expressed by chondrocytes from damaged cartilage, while VISG4, MARCO, CD163 and NRP1 were enriched in the synovial immune cells. The frequency of CSPG4+ and VSIG4+ EV subpopulations in OA SF was high. We conclude that pathogenic SF EVs carry knee OA severity-associated proteins and specific surface markers, which could be developed as a new source of diagnostic biomarkers or therapeutic targets in OA.

Depolarized Mitochondrial Membrane Potential and Elevated Calcium in Platelets of Sickle Cell Disease

Hemolysis, a crucial feature of Sickle cell disease (SCD), is a key player for cellular activation leading to various complications including thrombosis. In response to hemolysis, platelets get activated and release components that are necessary for further platelet activation and aggregation. Thus, it is believed that platelets contribute to the development of thrombotic complications. Platelets in SCD are expected to be affected due to common cause of hemolysis. To measure the surface markers of platelets including P-Selectin, Phosphatidyl Serine and integrin αIIbβ3 in SCD patients and healthy controls in order to understand the status of the platelets in SCD. To measure the surface markers of activated platelets using flow cytometry. Since mitochondria and calcium play an important role in cellular functions, the mitochondrial membrane potential and calcium content of platelets in SCD were also evaluated using flow cytometry. In the present study, we have observed significant increase of calcium level in SCD platelets. Further, the loss of mitochondrial membrane potential in SCD platelets was found to be significantly higher when compared to platelets of healthy controls. Though the surface markers of activated platelets in SCD remain unchanged, increased level of calcium and mitochondrial membrane potential loss suggest that the platelets in SCD are more prone to become activated. In order to understand the status of the platelets in SCD, apart from the surface markers, it is also important to assess the calcium levels and mitochondrial membrane potential of platelets.

Understanding the functional relevance of oral neutrophils, phenotype and properties in OSCC

Neutrophils are the predominant white blood cells (WBC) that are recruited to the sites of inflammation and infection. They are acknowledged to perform dual roles by promoting (pro-tumor) or by exhibiting anti-cancer properties (anti-tumor). Neutrophils are characterized based on the changes in phenotype and functional properties. To this context, circulating polymorphonuclear neutrophils (cPMN) and tumor-associated neutrophils (TANs) in cancer biology has been well explored but limited to oral polymorphonuclear neutrophils (oPMNs) in oral squamous cell carcinoma (OSCC). However, oPMNs are eminent in maintaining the healthy oral ecosystem by neutralizing microorganisms. Neutralization process enhances the expression of cell surface markers (CD11b, CD63, CD66, CD66b, CD66c, and CD66e) and inflammatory cytokines (TNF-α, IFN-γ, GM-CSF, and IL-8) and increases the recruitment of neutrophils. Along with the inflammation, it has been reported that CEACAM1 and chemerin also favors the infiltration of neutrophils to the cancer site. This indicates that oPMN might contribute to the aetiology of OSCC. The main objective of this review is to explore, the production and migration of oPMNs to the oral cavity, their phenotypes and possible role in OSCC.

Cancer Stem Cells And Anti-Tumor Immunity

Cancer stem cells (CSCs) are correlated with poor clinical outcome due to their contribution to chemotherapy resistance and formation of metastasis. Multiple cell surface and enzymatic markers have been characterized to identify CSCs, which is important for diagnosis, therapy, and prognosis. This review underlines the role of CSCs and circulating tumor cells (CTCs) in tumor relapse and metastasis, the characteristics of CSC and CTC biomarkers, and the techniques used for the detection of these cells. We also summarized novel therapeutic approaches toward targeting CSCs, especially focusing on the role of immune checkpoint blockades (ICB), such as anti-programmed death 1 (anti-PD1) and anti-programmed death ligand-1 (anti-PDL1) therapies. Additionally, we address an intriguing new mechanism of action for small molecular drugs, such as telomere targeted therapy 6-thio-2'deoxyguanosine (6-thio-dG), and how it reshapes tumor microenvironment to overcome ICB resistance. There are indications, that, personalized cancer therapy targeting CSC populations in conjunction with immune-mediated strategy hold promise for the removal of residual therapy-resistant CSCs in the near future.

The Provenance, Providence, and Position of Endothelial Cells in Injured Spinal Cord Vascular Pathology

Endothelial cells (ECs) and pericytes are present in all blood vessels. Their position confers an important role in controlling oxygen and nutrient transportation to the different organs. ECs can adopt different morphologies based on their need and functions. Both ECs and pericytes express different surface markers that help in their identification, but heterogeneity and overlapping between markers among different cells pose a challenge for their precise identification. Spatiotemporal association of ECs and pericytes have great importance in sprout formation and vessel stabilization. Any traumatic injury in CNS may lead to vascular damage along with neuronal damage. Hence, ECs-pericyte interaction by physical contact and paracrine molecules is crucial in recovering the epicenter region by promoting angiogenesis. ECs can transform into other types of cells through endothelial-mesenchymal transition (EndMT), promoting wound healing in the epicenter region. Various signaling pathways mediate the interaction of ECs with pericytes that have an extensive role in angiogenesis. In this review, we discussed ECs and pericytes surface markers, the spatiotemporal association and interaction of ECs-pericytes, and signaling associated with the pathology of traumatic SCI. Linking the brain or spinal cord-specific pathologies and human vascular pathology will pave the way toward identifying new therapeutic targets and developing innovative preventive strategies. Endothelial-pericyte interaction strategic for formation of functional neo-vessels that are crucial for neurological recovery.

Single-Cell Antibody Sequencing in Atherosclerosis Research

The transcriptomic information obtained by single cell RNA sequencing (scRNA-seq) can be supplemented by information on the cell surface phenotype by using oligonucleotide-tagged monoclonal antibodies (scAb-Seq). This is of particular importance in immune cells, where the correlation between mRNA and cell surface expression is very weak. scAb-Seq is facilitated by the availability of commercial antibodies and antibody mixes. Now panels of up to 200 antibodies are available for human and mouse cells. Proteins are detected by antibodies conjugated to a tripartite DNA sequence that contains a primer for amplification and sequencing, a unique oligonucleotide that acts as an antibody barcode and a poly(dA) sequence, simultaneously detecting extension of antibody-specific DNA sequences and cDNAs in the same poly(dT)-primed reaction. For each cell, surface protein expression is captured and sequenced along with the cell's transcriptome. Here, we list the steps needed to produce antibody sequencing data from tissue or blood cells.

Functional characterization of CD49f+ hepatic stem/progenitor cells in adult mice liver

Hepatic Stem/progenitor cells (HSPCs) have gained a large amount of interest for treating acute liver disease. However, the isolation and identification of HSPCs are unclear due to the lack of cell-specific surface markers. To isolate adult HSPCs, we used cell surface-marking antibodies, including CD49f and Sca-1. Two subsets of putative HSPCs, Lin^-CD45^-Sca-1^-CD49f⁺ (CD49f⁺) and Lin^-CD45^-Sca-1⁺CD49f^- (Sca-1⁺) cells, were isolated from adult mice liver by flow cytometry. Robust proliferative activity and clonogenic activity were found in both CD49f⁺ and Sca-1⁺ cells through colony-forming tests and cell cycle analyses. Immunofluorescence staining revealed that CD49f⁺ cells expressed ALB and CK-19 while Sca-1⁺ cells expressed only ALB, indicating that CD49f⁺ cells were bipotential and capable of differentiating into hepatocyte and cholangiocyte. Consequently, PAS stain showed that differentiated CD49f⁺ and Sca-1⁺ cells synthesised glycogen, indicating they could differentiate into functional hepatocytes. mRNA expression profile indicated that both CD49f⁺ and Sca-1⁺ cells showed differential expression of genes that are associated with liver progenitor function such as Sox9 and EpCam. Moreover, two subsets of putative HSPCs were activated by DDC and we found that their abundance and proliferation increased with age. In summary, we hypothesized that CD49f⁺ cells were a type of potential HSPCs and may be utilised for clinical stem cell therapy.

High-throughput surface marker screen on primary human breast tissues reveals further cellular heterogeneity

BACKGROUND

Normal human breast tissues are a heterogeneous mix of epithelial and stromal subtypes in different cell states. Delineating the spectrum of cellular heterogeneity will provide new insights into normal cellular properties within the breast tissue that might become dysregulated in the initial stages of cancer. Investigation of surface marker expression provides a valuable approach to resolve complex cell populations. However, the majority of cell surface maker expression of primary breast cells have not been investigated.

METHODS

To determine the differences in expression of a range of uninvestigated cell surface markers between the normal breast cell subpopulations, primary human breast cells were analysed using high-throughput flow cytometry for the expression of 242 cell surface proteins in conjunction with EpCAM/CD49f staining.

RESULTS

We identified 35 surface marker proteins expressed on normal breast epithelial and/or stromal subpopulations that were previously unreported. We also show multiple markers were equally expressed in all cell populations (e.g. CD9, CD59, CD164) while other surface markers were confirmed to be enriched in different cell lineages: CD24, CD227 and CD340 in the luminal compartment, CD10 and CD90 in the basal population, and CD34 and CD140b on stromal cells.

CONCLUSIONS

Our dataset of CD marker expression in the normal breast provides better definition for breast cellular heterogeneity.

Lactobacillus johnsonii activates porcine monocyte derived dendritic cells maturation to modulate Th cellular immune response

Lactobacilli are abundant in the intestinal tract where they constantly regulate immune system via interacting with a great diversity of immune cells, such as dendritic cells (DCs). Notably, DCs are powerful antigen-presenting cells and they are capable of initiating primary immune responses. In this study, we studied the effects of Lactobacillus johnsonii (L. johnsonii) and Lactobacillus johnsonii cell-free supernatant (L. johnsonii-CFS) on the activation of porcine monocyte-derived dendritic cells (MoDCs) and their regulation of Th cellular immune responses in vitro. The MoDCs generated from porcine peripheral blood monocytes were stimulated by L. johnsonii and L. johnsonii-CFS, respectively. Pre-incubation with L. johnsonii increased expression of CD172a, CD80, major histocompatibility complex class II (MHCII) in MoDCs, and enhanced the ability of MoDCs to induce the proliferation of CD4⁺ T cell, while pre-incubation with L. johnsonii-CFS merely upregulated the expression of MHCII. Analysis of the cytokines showed that L. johnsonii stimulated up-regulation of Th1-type cytokines (IL-12p40, IFN-γ, TNF-α), pro-inflammatory cytokine IL-1β, chemokine CCL20, and Treg-type / anti-inflammatory cytokines IL-10 in MoDCs. Notably, a high production of IL-10 was observed in the MoDCs treated with L. johnsonii-CFS, indicating L. johnsonii-CFS exerted anti-inflammatory effects. Furthermore, L. johnsonii induced up-regulation of TLR2 and TLR6, but L. johnsonii-CFS not. Moreover, MoDCs stimulated by L. johnsonii mainly promoted T cell differentiate into Th1/Th2/Treg cells and plays an important role in improving the balance between Th1/Th2/Treg-type cells, whereas MoDCs stimulated by L. johnsonii-CFS mainly directed T cell to Th2/Treg subset polarization. In conclusion, L. johnsonii and L. johnsonii-CFS exhibited the ability of modulating innate immunity by regulating immunological functions of MoDCs in vitro, suggesting their potential ability to use as microecological preparations and medicines.

Quantification of Antibody Persistence for Cell Surface Protein Labeling

Introduction

Antibodies are an essential research tool for labeling surface proteins but can potentially influence the behavior of proteins and cells to which they bind. Because of this, researchers and clinicians are interested in the persistence of these antibodies, particularly for live-cell applications. We developed an easily adoptable method for researchers to characterize antibody removal timelines for any cell-antibody combination, with the benefit of studying broad, hypothesized mechanisms of antibody removal.

Methods

We developed a method using four experimental conditions to elucidate the contributions of possible factors influencing antibody removal: cell proliferation, internalization, permanent dissociation, and environmental perturbation. This method was tested on adipose-derived stem cells and a human lung fibroblast cell line with anti-CD44, CD90, and CD105 antibodies. The persistence of the primary antibody was probed using a fluorescent secondary antibody daily over 10 days. Relative contributions by the antibody removal mechanisms were quantified based on differences between the four culture conditions.

Results

Greater than 90% of each antibody tested was no longer present on the surface of the two cell types after 5 days, with removal observed in as little as 1 day post-labeling. Anti-CD90 antibody was primarily removed by environmental perturbation, anti-CD105 antibody by internalization, and anti-CD44 antibody by a combination of all four factors.

Conclusions

Antibody removal mechanism depended on the specific antibody tested, while removal timelines for the same antibody depended more on cell type. This method should be broadly relevant to researchers interested in quantifying an initial timeframe for uninhibited use of antibody-labeled cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12195-021-00670-3.

Cancer stem cells in colorectal cancer and the association with chemotherapy resistance

The incidence and mortality of colorectal cancer (CRC) have always been among the highest in the world, although the diagnosis and treatment are becoming more and more advanced. At present, the main reason is that patients have acquired drug resistance after long-term conventional drug treatment. An increasing number of evidences confirm the existence of cancer stem cells (CSCs), which are a group of special cells in cancer, only a small part of cancer cells. These special cell populations are not eliminated by chemotherapeutic drugs and result in tumor recurrence and metastasis after drug treatment. CSCs have the ability of self-renewal and multidirectional differentiation, which is associated with the occurrence and development of cancer. CSCs can be screened and identified by related surface markers. In this paper, the characteristic surface markers of CSCs in CRC and the related mechanism of drug resistance will be discussed in detail. A better understanding of the mechanism of CSCs resistance to chemotherapy may lead to better targeted therapy.

Subpopulations of exosomes purified via different exosomal markers carry different microRNA contents

The heterogeneity of exosome populations presents a great challenge to their study. The current study was designed to investigate the potential heterogeneity miRNA contents in circulating exosomes purified via different exosomal markers. In this study, exosomes from the serum of C57BL/6 mice after cecum ligation and perforation (CLP) or sham operation were isolated by precipitation using ExoQuick-TC and affinity purified with anti-Rab5b, anti-CD9, anti-CD31, and anti-CD44 antibodies using the Exo-Flow Exosome Capture kit to collect exosome subpopulations. RNA extracted from the exosomes isolated by ExoQuick-TC were profiled by next-generation sequencing (NGS). Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was also employed to determine the expression profiles of four representative exosomal miRNAs (mmu-miR-486-5p, mmu-miR-10a-5p, mmu-miR-143-3p, and mmu-miR-25-3p) selected from the NGS analysis. The results revealed that the expression patterns of these miRNAs in exosomes isolated by ExoQuick-TC as determined by RT-qPCR and NGS were similar, showing upregulation of mmu-miR-10a-5p and mmu-miR-143-3p but downregulation of mmu-miR-25-3p and mmu-miR-486-5p following CLP when compared to the levels in exosomes from sham control mice. However, their expression levels in the antibody-captured exosome subpopulations varied. The miRNAs in the exosomes captured by anti-Rab5b or anti-CD9 antibodies were more similar to those isolated by ExoQuick-TC than to those captured by anti-CD44 antibodies. However, there were no significant differences in these four miRNAs in CD31-captured exosomes. This study demonstrated that purification with different exosomal markers allows the collection of different exosome subpopulations with various miRNA contents. The results of this study demonstrate the heterogeneity of circulating exosomes and suggest the importance of stratifying exosome subpopulations when using circulating exosomes as biomarkers or investigating exosome function. In addition, this study also emphasized the necessity of using a consistent exosome marker across different samples as detecting biomarkers.

Novel agents targeting leukemia cells and immune microenvironment for prevention and treatment of relapse of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation

Relapse remains the worst life-threatening complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with acute myeloid leukemia (AML), whose prognosis has been historically dismal. Given the rapid development of genomics and immunotherapies, the interference strategies for AML recurrence have been changing these years. More and more novel targeting agents that have received the U.S. Food and Drug Administration (FDA) approval for de novo AML treatment have been administrated in the salvage or maintenance therapy of post-HSCT relapse. Targeted strategies that regulate the immune microenvironment of and optimize the graft versus leukemia (GVL) effect of immune cells are gradually improved. Such agents not only have been proven to achieve clinical benefits from a single drug, but if combined with classic therapies, can significantly improve the poor prognosis of AML patients who relapse after allo-HSCT. This review will focus on currently available and promising upcoming agents and also discuss the challenges and limitations of targeted therapies in the allogeneic hematopoietic stem cell transplantation community.

The Progresses of Spermatogonial Stem Cells Sorting Using Fluorescence-Activated Cell Sorting

In recent years, the research on stem cells has been more and more in-depth, and many achievements have been made in application. However, due to the small number of spermatogonial stem cells (SSCs) and deficiency of efficient markers, it is difficult to obtain very pure SSCs, which results in the research on them being hindered. In fact, many methods have been developed to isolate and purify SSCs, but these methods have their shortcomings. Fluorescence-activated cell sorting (FACS), as a method to enrich SSCs with the help of specific surface markers, has the characteristics of high efficiency and accuracy in enrichment of SSCs, thus it is widely accepted as an effective method for purification of SSCs. This review summarizes the recent studies on the application of FACS in SSCs, and introduces some commonly used markers of effective SSCs sorting, aiming to further optimize the FACS sorting method for SSCs, so as to promote the research of germline stem cells and provide new ideas for the research of reproductive biology.

Commissioning and quality assurance of a novel solution for respiratory-gated PBS proton therapy based on optical tracking of surface markers

We present the commissioning and quality assurance of our clinical protocol for respiratory gating in pencil beam scanning proton therapy for cancer patients with moving targets. In a novel approach, optical tracking has been integrated in the therapy workflow and used to monitor respiratory motion from multiple surrogates, applied on the patients' chest. The gating system was tested under a variety of experimental conditions, specific to proton therapy, to evaluate reaction time and reproducibility of dose delivery control. The system proved to be precise in the application of beam gating and allowed the mitigation of dose distortions even for large (1.4cm) motion amplitudes, provided that adequate treatment windows were selected. The total delivered dose was not affected by the use of gating, with measured integral error within 0.15cGy. Analysing high-resolution images of proton transmission, we observed negligible discrepancies in the geometric location of the dose as a function of the treatment window, with gamma pass rate greater than 95% (2%/2mm) compared to stationary conditions. Similarly, pass rate for the latter metric at the 3%/3mm level was observed above 97% for clinical treatment fields, limiting residual movement to 3mm at end-exhale. These results were confirmed in realistic clinical conditions using an anthropomorphic breathing phantom, reporting a similarly high 3%/3mm pass rate, above 98% and 94%, for regular and irregular breathing, respectively. Finally, early results from periodic QA tests of the optical tracker have shown a reliable system, with small variance observed in static and dynamic measurements.

Regulatory T cells in patients with early untreated rheumatoid arthritis: Phenotypic changes in the course of methotrexate treatment

Rheumatoid arthritis (RA) is frequent systemic autoimmune disease characterized by excessive activation of collagen-specific T helper cells, and elevated level of autoantibodies in the serum. Development of RA is associated with defect in compartment of regulatory CD4+Foxp3+ T cells (Treg), but data concerning suppressive potential of Treg population in RA patients are contradictory and depend on the stage of disease. In this study we aimed to characterize abundance and phenotypic markers of CD4+Foxp3+ Treg in peripheral blood of healthy donors compared to untreated early RA patients to find potential correlations with the disease activity, antibody level, and absolute numbers and proportion of different subpopulations of T cells. Moreover, we assessed the influence of methotrexate (MT) treatment on percentage and absolute numbers of CD4+Foxp3+ Treg from the peripheral blood of untreated early RA patients. We demonstrate that increase and phenotypic changes in Treg population correlate well with response to MT. Analysis of the cohorts of matched RA patients (n = 45) and healthy controls (n = 20) revealed that patients with untreated early RA demonstrate substantial decrease in blood Treg percentage and absolute number, as well as low level of activated Treg surface markers in comparison to healthy control. The defect in Treg compartment negatively correlates with both RA activity and antibody level. MT treatment of patients with early untreated RA increases both proportion and absolute number of Treg with high level of activation markers, suggesting an increase of their functional capacity. Here we speculate the role of Tregs as specific cellular marker of successful RA treatment.

Prospective isolation of chondroprogenitors from human iPSCs based on cell surface markers identified using a CRISPR-Cas9-generated reporter

Background

Articular cartilage shows little or no capacity for intrinsic repair, generating a critical need of regenerative therapies for joint injuries and diseases such as osteoarthritis. Human-induced pluripotent stem cells (hiPSCs) offer a promising cell source for cartilage tissue engineering and in vitro human disease modeling; however, off-target differentiation remains a challenge during hiPSC chondrogenesis. Therefore, the objective of this study was to identify cell surface markers that define the true chondroprogenitor population and use these markers to purify iPSCs as a means of improving the homogeneity and efficiency of hiPSC chondrogenic differentiation.

Methods

We used a CRISPR-Cas9-edited COL2A1-GFP knock-in reporter hiPSC line, coupled with a surface marker screen, to identify a novel chondroprogenitor population. Single-cell RNA sequencing was then used to analyze the distinct clusters within the population. An unpaired t test with Welch’s correction or an unpaired Kolmogorov-Smirnov test was performed with significance reported at a 95% confidence interval.

Results

Chondroprogenitors expressing CD146, CD166, and PDGFRβ, but not CD45, made up an average of 16.8% of the total population. Under chondrogenic culture conditions, these triple-positive chondroprogenitor cells demonstrated decreased heterogeneity as measured by single-cell RNA sequencing with fewer clusters (9 clusters in unsorted vs. 6 in sorted populations) closer together. Additionally, there was more robust and homogenous matrix production (unsorted: 1.5 ng/ng vs. sorted: 19.9 ng/ng sGAG/DNA; p < 0.001) with significantly higher chondrogenic gene expression (i.e., SOX9, COL2A1, ACAN; p < 0.05).

Conclusions

Overall, this study has identified a unique hiPSC-derived subpopulation of chondroprogenitors that are CD146⁺/CD166⁺/PDGFRβ⁺/CD45⁻ and exhibit high chondrogenic potential, providing a purified cell source for cartilage tissue engineering or disease modeling studies.

Effect of Substrate Topography and Chemistry on Human Mesenchymal Stem Cell Markers: A Transcriptome Study

Background and Objectives

The International Society for Cellular Therapy (ISCT) proposed a set of minimal markers for identifying human mesenchymal stromal cells (hMSCs) in 2007. Since then, with the growing interest of better characterising hMSCs, various additional surface markers have been proposed. However, the impact of how culture conditions, in particular, the culture surface, vary the expression of hMSC markers was overlooked.

Methods and Results

In this study, we utilized the RNA sequencing data on hMSCs cultured on different surfaces to investigate the variation of the proposed hMSC biomarkers. One of the three ISCT proposed positive biomarker, CD90 was found to be significantly down regulated on hMSCs culture on fibrous surfaces when compared to flat surfaces. The detected gene expression values for 177 hMSCs biomarkers compiled from the literature are reported here. Correlation and cluster analysis revealed the existence of different biomarker communities that displayed a similar expression profile. We found a list of hMSCs biomarkers which are the least sensitive to a change in surface properties and another list of biomarkers which are found to have high sensitivity to a change in surface properties.

Conclusions

This study demonstrated that substrate properties have paramount effect on altering the expressions of hMSCs biomarkers and the proposed list of substrate-stable and substrate-sensitive biomarkers would better assist in the population characterisation. However, proteomic level analysis would be essential to confirm the observations noted.

Analysis of hematopoietic stem cells using a composite approach

Stem cells or Cancer stem cells (CSCs) have now been identified in different type of tissues by using surface markers. Functional assays such as ALDEFLUOR and side population which are marker independent have been additional approaches. However, whether all these approaches identify the same population of cells remain uncertain. To address this issue we have used hematopoietic stem cells as a model. Peripheral blood stem cells enumerated by CD34 are used routinely in bone marrow transplantation which supports the recovery of bone marrow after ablative chemotherapy or radiation. Hematopoietic stem cells (HSCs) were obtained from normal donor bone marrow (n = 5) and G-CSF stimulated peripheral blood stem cells (PBSCs) (n = 5) from patients undergoing leukapheresis prior to bone marrow transplantation. The stem cells were identified by combining CD34 expression with functional assays (ALDEFLUOR and side population). The cell cycle profile was further determined by simultaneous labeling of these cells with Hoechst and Pyronin Y. The simultaneous analysis showed that both CD34+ and CD34- cells co-exist with ALDH1A1+ cells but side population did not segregate with CD34+ cells. Though stem cell populations identified by functional assays were different, the cell cycle analysis showed that both ALDH1A1+ and CD34+ cells were in the G1 phase of cell cycle rather than in the quiescent (G0) phase.

Synergism between phorbol-12-myristate-13-acetate and vitamin D3 in the differentiation of U937 cells to monocytes and macrophages

Phorbol-12-myristate-13-acetate (PMA) and 1,25-dihydroxyvitamin D3 (VD3) are stimuli commonly used to induce macrophage differentiation in monocytic cell lines, but the extent of differentiation in comparison to primary tissue macrophages is unclear. Here, we examine the morphological/phenotypic markers associated with differentiation of U937 cells into monocytes/macrophages, in response to PMA or VD3 treatment. PMA stimulus but not with VD3, induced changes in cell morphology indicative of differentiation, but did not show differentiation comparable to monocyte-derive macrophage (MDM). The cells treated with PMA+VD3 for 2 days (d) acquired morphological/phenotypic features similar to those acquired by monocytes. In contrast, U937 cells treated for 2d with PMA and VD3 followed by 6d of resting in culture without PMA but in the presence of VD3 acquired morphological and phenotypic markers similar to those of MDM; i.e. reduced nucleus/cytoplasmic ratio, high auto-fluorescence and cytoplasmic complexity. Furthermore, low expression of CD14/TLR2 and high expression of CD68/CD86 were observed. In conclusion, our results indicate a synergistic effect between PMA and VD3 in U937 cells differentiation into both monocytes or macrophages and we propose a modified PMA differentiation protocol to enhance monocyte/macrophage differentiation of U937 cells.

In vitro assessment of silver nanoparticles immunotoxicity

This study aimed to characterize unwanted immune effects of nanoparticles (NP) using THP-1 cells, human whole blood and enriched peripheral blood monocytes. Commercially available silver NP (AgNP < 100 nm, also confirmed by Single Particle Extinction and Scattering) were used as prototypical NP. Cells were treated with AgNP alone or in combination with classical immune stimuli (i.e. LPS, PHA, PWM) and cytokine assessed; in addition, CD54 and CD86 expression was evaluated in THP-1 cells. AgNP alone induced dose-related IL-8 production in all models, with higher response observed in THP-1 cells, possibly connected to different protein corona formation in bovine versus human serum. AgNP potentiated LPS-induced IL-8 and TNF-α, but not LPS-induced IL-10. AgNP alone induced slight increase in IL-4, and no change in IFN-γ production. While responses to PHA in term of IL-4 and IFN-γ production were not affected, increased PWM-induced IL-4 and IFN-γ production were observed, suggesting potentiation of humoral response. Reduction in PHA-induced IL-10 was observed. Overall, results indicate immunostimulatory effects. THP-1 cells work as well as primary cells, representing a useful and practical alternative, with the awareness that from a physiological point of view the whole blood assay is the one that comes closest to reality.

Surface Antigen-Based Identification of In Vitro Expanded Skeletal Muscle-Derived Mesenchymal Stromal/Stem Cells Using Flow Cytometry

Mesenchymal stem/stromal cells (MSCs) can be isolated from several connective tissues in the adult organism by harnessing their propensity for plastic adherence in vitro. Upon culture expansion, the resulting cell cultures are composed of many different cell types at different stages of differentiation. Hence, their identity must be confirmed. Flow cytometry is an indispensable method for accurate quantification of MSC surface antigens. Here, we present a protocol that uses flow cytometry for the identification of MSCs based on the set of surface antigens required by the International Society for Cellular Therapy.

Evaluation of profile and functionality of memory T cells in pulmonary tuberculosis

The cells T CD4+ T and CD8+ can be subdivided into phenotypes naïve, T of central memory, T of effector memory and effector, according to the expression of surface molecules CD45RO and CD27. The T lymphocytes are cells of long life with capacity of rapid expansion and function, after a new antigenic exposure. In tuberculosis, it was found that specific memory T cells are present, however, gaps remain about the role of such cells in the disease immunology. In this study, the phenotypic profile was analyzed and characterized the functionality of CD4+ T lymphocytes and CD8+ T cells of memory and effector, in response to specific stimuli in vitro, in patients with active pulmonary TB, compared to individuals with latent infection with Mycobacterium tuberculosis the ones treated with pulmonary TB. It was observed that the group of patients with active pulmonary tuberculosis was the one which presented the highest proportion of cells T CD4+ of central memory IFN-ɣ+ e TNF-α+, suggesting that in TB, these T of central memory cells would have a profile of protective response, being an important target of study for the development of more effective vaccines; this group also developed lower proportion of CD8+ T effector lymphocytes than the others, a probable cause of specific and less effective response against the bacillus in these individuals; the ones treated for pulmonary tuberculosis were those who developed higher proportion of T CD4+ of memory central IL-17+ cells, indicating that the stimulation of long duration, with high antigenic load, followed by elimination of the pathogen, contribute to more significant generation of such cells; individuals with latent infection by M. tuberculosis and treated for pulmonary tuberculosis, showed greater response of CD8+ T effector lymphocytes IFN-ɣ+ than the controls, suggesting that these cells, as well as CD4+ T lymphocytes, have crucial role of protection against M. tuberculosis. These findings have contributed to a better understanding of the immunologic changes in M. tuberculosis infection and the development of new strategies for diagnosis and prevention of tuberculosis.

Tumor-Initiating Cells: a criTICal review of isolation approaches and new challenges in targeting strategies

Most cancers contain a subpopulation of highly tumorigenic cells, known as cancer stem cells (CSCs) or tumor-initiating cells (TICs). Targeting TICs may be essential to achieve cure, because of their self-renewal and tumorigenic properties as well as their resistance to conventional therapies. Despite significant advances in TIC biology, their isolation and identification remain largely disputed and incompletely established. In this review, we discuss the latest developments in isolation and culturing approaches of TICs, with focus on colorectal cancer (CRC). We feature recent findings on TIC-relevant signaling pathways and the metabolic identity of TICs, as well as their current clinical implications. Lastly, we highlight the influence of inter- and intra-tumoral heterogeneity on TIC function and targeting approaches.

Understanding of leukemic stem cells and their clinical implications

Since leukemic stem cells (LSCs) or cancer stem cells (CSCs) were found in acute myeloid leukemia (AML) in 1997, extensive studies have been contributed to identification and characterization of such cell populations in various tissues. LSCs are now generally recognized as a heterogeneous cell population that possesses the capacities of self-renewal, proliferation and differentiation. It has been shown that LSCs are regulated by critical surface antigens, microenvironment, intrinsic signaling pathways, and novel molecules such as some ncRNAs. To date, significant progress has been made in understanding of LSCs, leading to the development of numerous LSCs-targeted therapies. Moreover, various novel therapeutic agents targeting LSCs are undergoing clinical trials. Here, we review current knowledge of LSCs, and discuss the potential therapies and their challenges that are being tested in clinical trials for evaluation of their effects on leukemias.

Progress in research of surface markers of liver cancer stem cells

In recent years, cancer stem cell theory, in which a tumor is considered to consist of a handful of tumor stem cells and most common tumor cells, has been put forward by many scientists, which helps researchers to understand cancer from a new perspective. Isolating tumor stem cells is based mainly on their markers and in this way, many kinds of cancer stem cell markers have been confirmed, including live cancer stem cells. Isolating and identifying live cancer stem cells will provide a new hope for curing cancer. This paper mainly discusses seven liver cancer stem cell surface markers and their clinical significance.

Research progress and prospects of markers for liver cancer stem cells

Liver cancer is a common malignancy and surgery is the main treatment strategy. However, the prognosis is still poor because of high frequencies of postoperative recurrence and metastasis. In recent years, cancer stem cell (CSC) theory has evolved with the concept of stem cells, and has been applied to oncological research. According to cancer stem cell theory, liver cancer can be radically cured only by eradication of liver cancer stem cells (LCSCs). This notion has lead to the isolation and identification of LCSCs, which has become a highly researched area. Analysis of LCSC markers is considered to be the primary method for identification of LCSCs. Here, we provide an overview of the current research progress and prospects of surface markers for LCSCs.

Acute sleep deprivation in healthy young men: impact on population diversity and function of circulating neutrophils

Lack of sleep greatly affects our immune system. The present study investigates the acute effects of total sleep deprivation on blood neutrophils, the most abundant immune cell in our circulation and the first cell type recruited to sites of infection. Thus, the population diversity and function of circulating neutrophils were compared in healthy young men following one night of total sleep deprivation (TSD) or after 8h regular sleep. We found that neutrophil counts were elevated after nocturnal wakefulness (2.0 ± 0.2 × 10(9)/l vs. 2.6 ± 0.2 × 10(9)/l, sleep vs. TSD, respectively) and the population contained more immature CD16(dim)/CD62L(bright) cells (0.11 ± 0.040 × 10(9)/l [5.5 ± 1.1%] vs. 0.26 ± 0.020 × 10(9)/l [9.9 ± 1.4%]). As the rise in numbers of circulating mature CD16(bright)/CD62L(bright) neutrophils was less pronounced, the fraction of this subpopulation showed a significant decrease (1.8 ± 0.15 × 10(9)/l [88 ± 1.8%] vs. 2.1 ± 0.12 × 10(9)/l [82 ± 2.8%]). The surface expression of receptors regulating mobilization of neutrophils from bone marrow was decreased (CXCR4 and CD49d on immature neutrophils; CXCR2 on mature neutrophils). The receptor CXCR2 is also involved in the production of reactive oxygen species (ROS), and in line with this, total neutrophils produced less ROS. In addition, following sleep loss, circulating neutrophils exhibited enhanced surface levels of CD11b, which indicates enhanced granular fusion and concomitant protein translocation to the membrane. Our findings demonstrate that sleep loss exerts significant effects on population diversity and function of circulating neutrophils in healthy men. To which extent these changes could explain as to why people with poor sleep patterns are more susceptible to infections warrants further investigation.

Tracking the elusive fibrocyte: identification and characterization of collagen-producing hematopoietic lineage cells during murine wound healing

Fibrocytes are a unique population of circulating cells reported to exhibit characteristics of both hematopoietic and mesenchymal cells, and play an important role in wound healing. However, putative fibrocytes have been found to lose expression of hematopoietic surface markers such as CD45 during differentiation, making it difficult to track these cells in vivo with conventional methodologies. In this study, to distinguish hematopoietic and nonhematopoietic cells without surface markers, we took advantage of the gene vav 1, which is expressed solely on hematopoietic cells but not on other cell types, and established a novel transgenic mouse, in which hematopoietic cells are irreversibly labeled with green fluorescent protein and nonhematopoietic cells with red fluorescent protein. Use of single-cell transcriptional analysis in this mouse model revealed two discrete types of collagen I (Col I) expressing cells of hematopoietic lineage recruited into excisional skin wounds. We confirmed this finding on a protein level, with one subset of these Col I synthesizing cells being CD45+ and CD11b+, consistent with the traditional definition of a fibrocyte, while another was CD45- and Cd11b-, representing a previously unidentified population. Both cell types were found to initially peak, then reduce posthealing, consistent with a disappearance from the wound site and not a loss of identifying surface marker expression. Taken together, we have unambiguously identified two cells of hematopoietic origin that are recruited to the wound site and deposit collagen, definitively confirming the existence and natural time course of fibrocytes in cutaneous healing.

Correlation of cell surface marker expression with African swine fever virus infection

The expression of surface markers on African swine fever virus (ASFV) infected cells was evaluated to assess their involvement in infection. Previous findings indicated CD163 expression was correlated with ASFV susceptibility. However, in this study the expression of porcine CD163 on cell lines did not increase the infection rate of these cells indicating other factors are likely to be important in determining susceptibility to infection. On adherent porcine bone marrow (pBM) cells the expression of CD45 was strongly correlated with infection. CD163 and CD203a expression correlated at intermediate levels with infection, indicating cells expressing these markers could become infected but were not preferentially infected by the virus. Most of the cells expressing MHCII were infected, indicating that they may be preferentially infected although expression of MHCII was not essential for infection and a large percentage of the infected cells were MHCII negative. CD16 showed a marked decrease in expression following infection and significantly lower levels of infected cells were shown to express CD16. Altogether these results suggest CD163 may be involved in ASFV infection but it may not be essential; the results also highlight the importance of other cell markers which requiring further investigation.

THE CD 10 MARKER IN THE INVESTIGATION OF ACUTE LYMPHOBLASTIC LEUKAEMIA

Immunophenotyping of leukaemias is presently well established. It is invaluable for proper case management [1]. The most useful information on the management of cases of Acute Lymphocytic Leukaemia (ALL) is provided by the detection of the CD 10 marker on the leukaemic cell. The CD 10 positive ALL has since long been associated with a favourable prognosis as compared to the CD 10 negative ALL [1, 2]. As immunophenotyping is resource intensive, the monoclonal antibodies (MO ABS), are not in widespread use in our country. The expenses involved make this procedure prohibitive in most institutions. For this reason, a limited panel of MO ABS has been used in this study, with a special emphasis on the CD 10 marker. A total of 25 cases of ALL were studied. 17 cases were found to be positive for the CD 10 marker (68%). These cases were associated with a favourable prognosis as compared to the CD 10 negative group. Although, the diagnosis of ALL and leukaemias in general, is essentially based on the study of Romanowsky stained smears [3, 4], the additional information provided by the cell surface marker study results in better case management [1].

IMMUNOPHENOTYPING OF ACUTE LEUKAEMIAS : A CRITICAL ANALYSIS OF 35 CASES

Accurate classification of acute leukaemias is essential for proper case management. The utility of monoclonal antibodies in the diagnosis and classification of acute leukaemias is well established. This diagnostic utility relates primarily to two points : firstly the distinction between acute myeloid leukaemia and acute lymphoblastic leukaemia and secondly to subtypes of acute lymphoblastic leukaemia. Leukaemic cells were immunophenotyped using the alkaline phosphatase antialkaline phosphatase techniques. The monoclonal antibodies were very useful in distinguishing cases of acute myeloid leukaemia from acute lymphoblastic leukaemia. Cases of acute lymphoblastic leukaemia with CD10 positivity showed a better prognosis. T-cell acute lymphoblastic leukaemia was uncommon and was associated with unfavourable prognosis. The alkaline phosphatase antialkaline phosphatase technique served as a reliable and convenient method for immunophenotyping of leukaemias.