CD45- erythroid progenitor cells promote lymph node metastasis in gastric cancer by inducing a hybrid epithelial/mesenchymal state in lymphatic endothelial cells.

BACKGROUND AND AIMS: Specific mechanisms of lymph node (LN) metastasis in early-stage gastric cancer (GC) have not been elucidated. The role of anemia, a vital clinical feature of GC, in LN metastasis is also unclear. Since the number of erythroid progenitor cells (EPCs) is increased in chronic anemia, we investigated its association with LN metastasis in GC. METHODS: Flow cytometry and immunofluorescence analyses were performed to sort and study EPCs from the circulation and tumors of patients with stage I-III GC. The effect of these EPCs on the activation of T and B cells and on the functions of lymphatic endothelial cells (LECs) was determined, and their ability to promote LN metastasis was evaluated using a footpad-popliteal LN metastasis model based on two human adenocarcinoma GC cell lines in nude mice. The prognostic value of EPCs was also analyzed. RESULTS: The proportion of CD45- EPCs was higher in the mononuclear cells in the circulation, tumors, and LNs of GC patients with LN metastasis (N+) than in those of GC patients without LN metastasis (N0). In N+ patients, CD45- EPCs were more abundant in metastatic LNs than in non-metastatic LNs. Lymphatic vessel endothelial hyaluronan receptor 1 immunoreactivity in tumors revealed that CD45- EPCs were positively associated with nodal stages and lymph vessel density. Furthermore, CD45- EPCs increased LEC proliferation and migration through their S100A8/A9 heterodimer-induced hybrid epithelial/mesenchymal (E/M) state; however, they did not influence the invasion and tubulogenesis of LECs or T and B cell proliferation. CD45- EPCs promoted LN metastasis in vivo; the S100A8/A9 heterodimer mimicked this phenomenon. Finally, CD45- EPCs predicted the overall and disease-free survival of stage I-III GC patients after radical resection. CONCLUSIONS: The CD45- EPCs accumulated in GC tissues and metastatic LNs and promoted LN metastasis via the S100A8/9-induced hybrid E/M state of LECs, which was the specific mechanism of LN metastasis in the early stages of GC.

[In vitro production of red blood cells for future transfusion medicine].

Large-scale in vitro red blood cell (RBC) production has been attempted in recent years. Potential cell sources for RBC production include hematopoietic stem/progenitor cells, pluripotent stem cells, and immortalized erythroid progenitor cell lines, which can induce enucleated RBCs with characteristics such as oxygen-carrying capacity and deformability. A phase I clinical study of cultured RBCs produced from hematopoietic stem/progenitor cells has revealed a similar in vivo half-life between cultured and native RBCs. Thus, the application of cultured RBCs in blood transfusion is gradually advancing. However, a single transfusion requires a large number of cells, unlike other cell therapies. Therefore, developing a method to mass-produce RBCs from a small culture volume at a low cost is important in the future. This review summarizes the current status and prospects concerning in vitro RBC production using each cell source, which can improve future transfusion medicine.

LAG3+ erythroid progenitor cells inhibit HBsAg seroclearance during finite pegylated interferon treatment through LAG3 and TGF-ß.

HBsAg seroclearance, the ideal aim of anti-hepatitis B virus (HBV) treatment, cannot be achieved easily. Anemia is another common issue for chronic hepatitis B (CHB) patients, which leads to elevation of erythroid progenitor cells (EPCs) and immune suppression in cancer. This study investigated the role of EPCs in HBsAg seroclearance following pegylated interferon-α (PEG-IFN) treatment. CD45+EPC accumulation in CHB patients and an AAV/HBV mice model was found in the circulation and liver by flow cytometry and immunofluorescence tests. Wright-Giemsa staining showed that these pathological CD45+EPCs presented elevated erythroid cells with relative immature morphologies and atypical cells compared with the control cells. CD45+EPCs were associated with immune tolerance and decreased HBsAg seroclearance during finite PEG-IFN treatment. CD45+EPCs suppressed antigen non-specific T cell activation and HBV-specific CD8+T cells, partially through transforming growth factor ß (TGF-ß). RNA-seq revealed that CD45+EPCs in patients with CHB presented a distinct gene expression profile compared with CD45-EPCs and CD45+EPCs from cord blood. Notably, CD45+EPCs from patients with CHB expressed high level of Lymphocyte-activation gene 3 (LAG3), an immune checkpoint molecule, and were then defined as LAG3+EPCs. LAG3+EPCs diminished the function of antigen presenting cells through LAG3, which was another mechanism by which LAG3+EPCs' suppressed HBV-specific CD8+T cells. Anti-LAG3 and anti-TGF-ß combination treatment decreased serum HBeAg, HBV DNA levels and HBsAg level, as well as HBsAg-expression in hepatocytes during PEG-IFN treatment in the AAV/HBV mice model. Conclusions: LAG3+EPCs inhibited the efficacy of PEG-IFN treatment on HBsAg seroclearance induced by LAG3 and TGF-ß. Anti-LAG3, anti-TGF-ß and PEG-IFN combination treatment might facilitate HBV clearance.

The role of erythrocytes and erythroid progenitor cells in tumors.

In the current research context of precision treatment of malignant tumors, the advantages of immunotherapy are unmatched by conventional antitumor therapy, which can prolong progression-free survival and overall survival. The search for new targets and novel combination therapies can improve the efficacy of immunotherapy and reduce adverse effects. Since current research targets for immunotherapy mainly focus on lymphocytes, little research has been done on erythrocytes. Nucleated erythroid precursor stem cells have been discovered to play an essential role in tumor progression. Researchers are exploring new targets and therapeutic approaches for immunotherapy from the perspective of erythroid progenitor cells (EPCs). Recent studies have shown that different subtypes of EPCs have specific surface markers and distinct biological roles in tumor immunity. CD45+ EPCs are potent myeloid-derived suppressor cell-like immunosuppressants that reduce the patient's antitumor immune response. CD45- EPCs promote tumor invasion and metastasis by secreting artemin. A specific type of EPC also promotes angiogenesis and provides radiation protection. Therefore, EPCs may be involved in tumor growth, infiltration, and metastasis. It may also be an important cause of anti-angiogenesis and immunotherapy resistance. This review summarizes recent research advances in erythropoiesis, EPC features, and their impacts and processes on tumors.

Detection of erythroid progenitors and erythrocytopathies in patients with severe COVID-19 disease.

OBJECTIVES: To assess the effect of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection on erythropoiesis and red blood cells (RBC) surface markers by evaluating erythroid progenitor cells (CD [cluster of differentiation]71+/CD235a+) and RBC surface markers (CD235a and CD36), together with various hematological parameters. METHODS: This case-control study includes 47 participants recruited in the study: 30 patients with coronavirus disease 2019 (COVID-19) and 17 healthy individuals. The COVID-19 patients were recruited from the intensive care unit (ICU) of various hospitals in Makkah, Saudi Arabia. Blood samples were collected during July and September 2021. Red blood cells indices were measured using a CBC analyzer. The expression of CD235a, CD71, and CD36 was obtained using flow cytometry technique. The unpaired t-test was conducted to evaluate the differences in these markers in COVID-19 patients and healthy individuals. RESULTS: The data showed that more than half of the COVID-19 patients were anemic (64%). Expansion of erythroid progenitors (CD71+/CD235a+) was detected in the COVID-19 patients. Analysis of the expression of RBC surface markers, such as CD235a and CD36, showed that SARS-CoV-2 was associated with significantly higher expression of these markers in COVID-19 patients. CONCLUSION: Severe acute respiratory syndrome coronavirus-2 promoted the expansion of erythroid progenitors in the peripheral blood of COVID-19 patients. In addition, the expression of RBC surface markers was higher in COVID-19 patients. The expansion of erythroid progenitors and alteration of RBC surface markers can contribute to erythrocytopathies observed in severe COVID-19 patients and can therefore be used as prognostic factors.

Carbon Dots as a Potential Therapeutic Agent for the Treatment of Cancer-Related Anemia.

Due to the adverse effects of erythropoietin (EPO) on cancer patient survival, it is necessary to develop new agents that can be used to efficiently manage and treat cancer-related anemia. In this study, novel distinctive carbon dots, J-CDs, derived from jujube are designed, synthesized, and characterized. Based on the obtained results, this material comprises sp2 and sp3 carbon atoms, as well as oxygen/nitrogen-based groups, and it specifically promotes the proliferation of erythroid cells by stimulating the self-renewal of erythroid progenitor cells in vitro and in vivo. Moreover, J-CDs have no discernible effects on tumor proliferation and metastasis, unlike EPO. Transcriptome profiling suggests that J-CDs upregulate the molecules involved in hypoxia response, and they also significantly increase the phosphorylation levels of STAT5, the major transducer of signals for erythroid progenitor cell proliferation. Overall, this study demonstrates that J-CDs effectively promote erythrocyte production without affecting tumor proliferation and metastasis; thus, they may be promising agents for the treatment of cancer-related anemia.

[Effect of Rheb1 in the Development of Mouse Megakaryocyte-Erythroid Progenitor Cells].

OBJECTIVE: To investigate the effect of Rheb1 in the development of mouse megakaryocyte-erythroid progenitor cells and its related mechanism. METHODS: Rheb1 was specifically knocked-out in the hematopoietic system of Vav1-Cre;Rheb1fl/fl mice(Rheb1Δ/Δ mice). Flow cytometry was used to detect the percentage of red blood cells in peripheral blood and erythroid cells in bone marrow in Vav1-Cre;Rheb1fl/fl mice and control mice. The CFC assay was used to detect the differentiation ability of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Real-time fluorescence quantification PCR was used to detect the relative expression of PU.1,GATA-1,GATA-2,CEBPα and CEBPß of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Rapamycin was added to the culture medium, and it was used to detect the changes in cloning ability of megakaryocyte-erythroid progenitor cells from wild-type mice in vitro. RESULTS: After Rheb1 was knocked out, the development and stress response ability of megakaryocyte-erythroid progenitor cells in mice were weaken and the differentiation ability of megakaryocyte-erythroid progenitor cells in vitro was weaken. Moreover, the expression of GATA-1 of megakaryocyte-erythroid progenitor cells was decreased. Further, rapamycin could inhibit the differentiative capacity of megakaryocyte-erythroid progenitor cells in vitro. CONCLUSION: Rheb1 can regulate the development of megakaryocyte-erythroid progenitor cells probably through the mTOR signaling pathway in mice.

Derivation of Clinical-Grade Induced Pluripotent Stem Cell Lines from Erythroid Progenitor Cells in Xenofree Conditions.

One of the major hurdles in realizing the therapeutic potential of human-induced pluripotent stem cells (iPSC) is the generation of clinical-grade iPSC lines and their differentiated progenies for preclinical and clinical applications. Therefore, there is a need to have standardized protocols for efficient generation of clinical-grade iPSC lines from easily accessible somatic cells in feeder-free, xenofree GMP grade culture conditions without genomic integration of the reprogramming factors. Here, we provide a detailed protocol for expansion of erythroid progenitor cells from peripheral blood mononuclear cells (PBMNC) and generation of iPSC lines in feeder-free and xenofree culture conditions from these cells by using GMP grade reagents. With this optimized protocol, clinical-grade iPSC lines can be derived from erythroid progenitor cells expanded from peripheral blood, which is easy-to-access, minimally invasive, and can be obtained from any donors. It will have implications in developing a large number of iPSC lines from individual healthy donors, diseased patients, or donors with homozygous human leukocyte antigen (HLA) for "haplobanking."

Effect of Rheb1 in the Development of Mouse Megakaryocyte-Erythroid Progenitor Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of Rheb1 in the development of mouse megakaryocyte-erythroid progenitor cells and its related mechanism.@*METHODS@#Rheb1 was specifically knocked-out in the hematopoietic system of Vav1-Cre;Rheb1fl/fl mice(Rheb1Δ/Δ mice). Flow cytometry was used to detect the percentage of red blood cells in peripheral blood and erythroid cells in bone marrow in Vav1-Cre;Rheb1fl/fl mice and control mice. The CFC assay was used to detect the differentiation ability of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Real-time fluorescence quantification PCR was used to detect the relative expression of PU.1,GATA-1,GATA-2,CEBPα and CEBPβ of Rheb1 KO megakaryocyte-erythroid progenitor cells and control cells. Rapamycin was added to the culture medium, and it was used to detect the changes in cloning ability of megakaryocyte-erythroid progenitor cells from wild-type mice in vitro.@*RESULTS@#After Rheb1 was knocked out, the development and stress response ability of megakaryocyte-erythroid progenitor cells in mice were weaken and the differentiation ability of megakaryocyte-erythroid progenitor cells in vitro was weaken. Moreover, the expression of GATA-1 of megakaryocyte-erythroid progenitor cells was decreased. Further, rapamycin could inhibit the differentiative capacity of megakaryocyte-erythroid progenitor cells in vitro.@*CONCLUSION@#Rheb1 can regulate the development of megakaryocyte-erythroid progenitor cells probably through the mTOR signaling pathway in mice.

Ultrasound-Targeted Microbubble Destruction Alleviates Immunosuppression Induced by CD71+ Erythroid Progenitor Cells and Promotes PDL-1 Blockade Immunotherapy in the Lewis Lung Cancer Model.

The CD71+ erythroid progenitor cells (CECs) exhibit distinctive immunosuppressive properties and regulate antitumor immunity to enable tumor growth. We presented a novel and non-invasive approach to improving immunity by targeting the splenic CECs via sonoporation generated by ultrasound-targeted microbubble destruction (UTMD). The systematic immunity enhanced by the reduction of PDL-1-expressing CECs also benefits the PDL-1 blockade therapy. In the Lewis lung cancer (LLC) model, the study group was treated by UTMD for 10 min at the splenic area with or without anti-mouse PDL-1 intraperitoneal injection. The frequency of splenic CEC, lymphocyte, and cytokine production was analyzed by flow cytometry. Serum interleukin-2 (IL-2) was tested by ELISA. Tumor volume was evaluated by two-dimensional ultrasound. The UTMD treatment consisted of ultrasound sonication and Sonazoid™ microbubble injection through the caudal vein. The mechanic index (MI) of ultrasound was set between 0.98 and 1.03. The results showed a significant reduction of splenic CECs and increased frequency of CD8+ T cells treated by UTMD treatment in the late-stage tumor. Tumor growth could be inhibited by UTMD combined with PDL-1 blockade therapy. The frequencies of interferon-γ (IFN-γ) producing CD8+ and CD4+ T cells were significantly increased after being treated by the combination of UTMD and PDL-1 blockade, while the reactive oxygen species (ROS) production and the fraction of the TGF-ß-producing CD11b+ cells were significantly decreased. These preliminary findings suggest that UTMD enhances immune response and facilitates PDL-1 blockade therapy by targeting immunosuppressive CECs in the spleen. Our study provides new aspects and possibilities for treating cancer-related infection and tumor control in oncology.

The role of CD71+ erythroid cells in the regulation of the immune response.

Complex regulation of the immune response is necessary to support effective defense of an organism against hostile invaders and to maintain tolerance to harmless microorganisms and autoantigens. Recent studies revealed previously unappreciated roles of CD71+ erythroid cells (CECs) in regulation of the immune response. CECs physiologically reside in the bone marrow where erythropoiesis takes place. Under stress conditions, CECs are enriched in some organs outside of the bone marrow as a result of extramedullary erythropoiesis. However, the role of CECs goes well beyond the production of erythrocytes. In neonates, increased numbers of CECs contribute to their vulnerability to infectious diseases. On the other side, neonatal CECs suppress activation of immune cells in response to abrupt colonization with commensal microorganisms after delivery. CECs are also enriched in the peripheral blood of pregnant women as well as in the placenta and are responsible for the regulation of feto-maternal tolerance. In patients with cancer, anemia leads to increased frequency of CECs in the peripheral blood contributing to diminished antiviral and antibacterial immunity, as well as to accelerated cancer progression. Moreover, recent studies revealed the role of CECs in HIV and SARS-CoV-2 infections. CECs use a full arsenal of mechanisms to regulate immune response. These cells suppress proinflammatory responses of myeloid cells and T-cell proliferation by the depletion of ʟ-arginine by arginase. Moreover, CECs produce reactive oxygen species to decrease T-cell proliferation. CECs also secrete cytokines, including transforming growth factor ß (TGF-ß), which promotes T-cell differentiation into regulatory T-cells. Here, we comprehensively describe the role of CECs in orchestrating immune response and indicate some therapeutic approaches that might be used to regulate their effector functions in the treatment of human conditions.

Tumor Immune Evasion Induced by Dysregulation of Erythroid Progenitor Cells Development.

Cancer cells harness normal cells to facilitate tumor growth and metastasis. Within this complex network of interactions, the establishment and maintenance of immune evasion mechanisms are crucial for cancer progression. The escape from the immune surveillance results from multiple independent mechanisms. Recent studies revealed that besides well-described myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs) or regulatory T-cells (Tregs), erythroid progenitor cells (EPCs) play an important role in the regulation of immune response and tumor progression. EPCs are immature erythroid cells that differentiate into oxygen-transporting red blood cells. They expand in the extramedullary sites, including the spleen, as well as infiltrate tumors. EPCs in cancer produce reactive oxygen species (ROS), transforming growth factor ß (TGF-ß), interleukin-10 (IL-10) and express programmed death-ligand 1 (PD-L1) and potently suppress T-cells. Thus, EPCs regulate antitumor, antiviral, and antimicrobial immunity, leading to immune suppression. Moreover, EPCs promote tumor growth by the secretion of growth factors, including artemin. The expansion of EPCs in cancer is an effect of the dysregulation of erythropoiesis, leading to the differentiation arrest and enrichment of early-stage EPCs. Therefore, anemia treatment, targeting ineffective erythropoiesis, and the promotion of EPC differentiation are promising strategies to reduce cancer-induced immunosuppression and the tumor-promoting effects of EPCs.

Direct Comparison of Four Hematopoietic Differentiation Methods from Human Induced Pluripotent Stem Cells.

Induced pluripotent stem cells (iPSCs) are an invaluable resource for the study of human disease. However, there are no standardized methods for differentiation into hematopoietic cells, and there is a lack of robust, direct comparisons of different methodologies. In the current study we improved a feeder-free, serum-free method for generation of hematopoietic cells from iPSCs, and directly compared this with three other commonly used strategies with respect to efficiency, repeatability, hands-on time, and cost. We also investigated their capability and sensitivity to model genetic hematopoietic disorders in cells derived from Down syndrome and ß-thalassemia patients. Of these methods, a multistep monolayer-based method incorporating aryl hydrocarbon receptor hyperactivation ("2D-multistep") was the most efficient, generating significantly higher numbers of CD34+ progenitor cells and functional hematopoietic progenitors, while being the most time- and cost-effective and most accurately recapitulating phenotypes of Down syndrome and ß-thalassemia.

New Insights of Human Parvovirus B19 in Modulating Erythroid Progenitor Cell Differentiation.

Human parvovirus B19 (B19), a human pathogen of the erythroparvovirus genus, is responsible for a variety of diseases. B19 cause less symptoms in healthy individuals, also cause acute and chronic anemia in immunodeficiency patients. Transient aplastic crisis and pure red cell aplasia are two kinds of anemic hemogram, respectively, in acute and chronic B19 infection phase, especially occurring in patients with a shortened red cell survival or with immunodeficiency. In addition, B19-infected pregnant women may cause hydrops fetalis or fetal loss. B19 possesses high affinity to bone marrow and fetal liver due to its extremely restricted cytotoxicity to erythroid progenitor cells (EPCs) mediated by viral proteins. The nonstructural protein NS1 is considered to be the major pathogenic factor, which has been shown to inhibit the differentiation and maturation of EPCs through inducing viral DNA damage responses and cell cycle arrest. The time phase property of NS1 activity during DNA replication and conformity to transient change of hemogram are suggestive of its role in regulating differentiation of hematopoietic cells, which is not completely understood. In this review, we summarized the bridge between B19 NS1 and Notch signaling pathway or transcriptional factors GATA, which play an important role in erythroid cell proliferation and differentiation, to provide a new insight of the potential mechanism of B19-induced differential inhibition of EPCs.

Erythroid Progenitor Cells in Atlantic Salmon (Salmo salar) May Be Persistently and Productively Infected with Piscine Orthoreovirus (PRV).

Piscine orthoreovirus (PRV-1) can cause heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). The virus targets erythrocytes in the acute peak phase, followed by cardiomyocytes, before the infection subsides into persistence. The persistent phase is characterized by high level of viral RNA, but low level of viral protein. The origin and nature of persistent PRV-1 are not clear. Here, we analyzed for viral persistence and activity in various tissues and cell types in experimentally infected Atlantic salmon. Plasma contained PRV-1 genomic dsRNA throughout an 18-week long infection trial, indicating that viral particles are continuously produced and released. The highest level of PRV-1 RNA in the persistent phase was found in kidney. The level of PRV-1 ssRNA transcripts in kidney was significantly higher than that of blood cells in the persistent phase. In-situ hybridization assays confirmed that PRV-1 RNA was present in erythroid progenitor cells, erythrocytes, macrophages, melano-macrophages and in some additional un-characterized cells in kidney. These results show that PRV-1 establishes a productive, persistent infection in Atlantic salmon and that erythrocyte progenitor cells are PRV target cells.

Advances in the Development of Antiviral Strategies against Parvovirus B19.

Parvovirus B19 (B19V) is a human pathogenic virus, responsible for an ample range of clinical manifestations. Infections are usually mild, self-limiting, and controlled by the development of a specific immune response, but in many cases clinical situations can be more complex and require therapy. Presently available treatments are only supportive, symptomatic, or unspecific, such as administration of intravenous immunoglobulins, and often of limited efficacy. The development of antiviral strategies against B19V should be considered of highest relevance for increasing the available options for more specific and effective therapeutic treatments. This field of research has been explored in recent years, registering some achievements as well as interesting future perspectives. In addition to immunoglobulins, some compounds have been shown to possess inhibitory activity against B19V. Hydroxyurea is an antiproliferative drug used in the treatment of sickle-cell disease that also possesses inhibitory activity against B19V. The nucleotide analogues Cidofovir and its lipid conjugate Brincidofovir are broad-range antivirals mostly active against dsDNA viruses, which showed an antiviral activity also against B19V. Newly synthesized coumarin derivatives offer possibilities for the development of molecules with antiviral activity. Identification of some flavonoid molecules, with direct inhibitory activity against the viral non-structural (NS) protein, indicates a possible line of development for direct antiviral agents. Continuing research in the field, leading to better knowledge of the viral lifecycle and a precise understanding of virus-cell interactions, will offer novel opportunities for developing more efficient, targeted antiviral agents, which can be translated into available therapeutic options.

[Proportion and role of CD45+ erythroid progenitor cells in patients with tongue cancer metastasis].

Objective: To investigate the proportion and role of CD45+ erythroid progenitor cells (EPC) in patients with tongue cancer metastasis. Methods: The initial treatment of tongue cancer patients (n=40) from January 2017 to June 2018 in He'nan Provincial People's Hospital was included in this study. According to the presence or absence of lymph node metastasis, they were divided into tumor group (no lymph node metastasis was found in imaging and pathology) and metastasis group (both imaging and pathology confirmed lymph node metastasis). The expression of Ki-67 was detected by immunohistochemistry and the proportion of CD45+CD71+TER119+EPC was detected by flow cytometry. EPC was sorted by flow cytometry, interleukin-10 (IL-10) and transforming growth factor-ß (TGF-ß) were detected by enzyme-linked immunosorbent assay (ELISA), and reactive oxygen species (ROS) was detected by flow cytometry. Transwell was used for tumor invasion test; methyl thiazolyltetrazolium (MTT) assay was used to detect proliferation level. Results: There were 20 cases in the tumor group and metastasis group. There was no significant difference between the two groups in terms of age, sex, time of onset and size of tumors. Flow cytometry showed that the ratio of CD45+EPC in peripheral blood of tumor group and metastasis group was (1.2±0.2)% and (3.1±0.2)% (t=7.823, P<0.001). Correlation analysis showed that the ratio of CD45+EPC was positively correlated with the proliferation index of Ki-67 cells (r=0.592, P=0.006). The results of flow cytometry showed that the mean fluorescence intensity (MFI) of ROS in EPC was 102.1±22.9 in tumor group and 530.0±67.2 in metastasis group (t=6.025,P<0.001). The results of ELISA showed that the mass concentrations of IL-10 and TGF-ß in EPC supernatant of tumor group were (10.8±1.6) and (3.2±0.8) µg/L, respectively. The mass concentrations of IL-10 and TGF-beta in EPC supernatant of metastasis group were (26.9±3.7) and (6.4±0.9) µg/L, respectively (t=3.956, P=0.003; t=2.595, P=0.027). Transwell results showed that the proportion of invasive cells in the CD45+EPC group [(40.3±4.4)%] was higher than that in the control group [(17.5±2.2)%] (t=4.607, P=0.001). MTT proliferation experiment showed that the proliferation rate of the CD45+EPC group [(52.0±3.3)%] was higher than that of the control group [(30.5±1.9)%] (t=5.656, P<0.001). Conclusions: The proportion of CD45+EPC in patients with tongue cancer metastasis is significantly increased. CD45+EPC can promote the proliferation and metastasis of tongue cancer by secreting immunosuppressive molecules and ROS.

Antiviral activity of brincidofovir on parvovirus B19.

Parvovirus B19 (B19V), a single-stranded DNA virus in the family Parvoviridae, is a human pathogenic virus responsible for a wide range of clinical manifestations. Currently there is no approved antiviral therapy for parvovirus infection. The acyclic nucleoside phosphonate cidofovir (CDV) has been demonstrated to inhibit replication of B19V in vitro. The aim of the present study was to evaluate whether brincidofovir (BCV), a novel lipid conjugate of CDV, could also inhibit B19V replication. Experiments were carried out in erythroid progenitor cells (EPCs) and UT7/EpoS1 cells, infected with B19V and cultured in the presence of different concentrations of BCV and CDV for comparison. The dynamics of viral replication was evaluated by a qPCR-based assay and the extent of inhibition of viral replication exerted by the compounds determined, along with the effect of the compounds on cell viability and cell proliferation rates. Results confirmed that BCV showed significantly higher antiviral activity against B19V compared to CDV in both cell-based systems. For BCV, the calculated EC50 values were in the range 6.6-14.3 µM in EPCs and 0.22-0.63 µM in UT7/EpoS1 cells. In comparison, the EC50 values for CDV were >300 µM in EPCs and 16.1 µM in UT7/EpoS1 cells. Concurrently, the effects on cell viability were observed at a much higher concentration of BCV, with calculated CC50 values in the range 93.4-102.9 µM in EPCs and 59.9-66.8 µM in UT7/Epos1. The antiviral activity was observed specifically with the metabolically active stereoisomer of BCV suggesting that CDV-diphosphate, the metabolite of both BCV and CDV, was the active antiviral. Our results support a selective role for BCV in the inhibition of B19 viral replication.

Proportion and role of CD45+ erythroid progenitor cells in patients with tongue cancer metastasis / 中华口腔医学杂志

Objective@#To investigate the proportion and role of CD45+ erythroid progenitor cells (EPC) in patients with tongue cancer metastasis.@*Methods@#The initial treatment of tongue cancer patients (n=40) from January 2017 to June 2018 in He'nan Provincial People′s Hospital was included in this study. According to the presence or absence of lymph node metastasis, they were divided into tumor group (no lymph node metastasis was found in imaging and pathology) and metastasis group (both imaging and pathology confirmed lymph node metastasis). The expression of Ki-67 was detected by immunohistochemistry and the proportion of CD45+CD71+TER119+EPC was detected by flow cytometry. EPC was sorted by flow cytometry, interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) were detected by enzyme-linked immunosorbent assay (ELISA), and reactive oxygen species (ROS) was detected by flow cytometry. Transwell was used for tumor invasion test; methyl thiazolyltetrazolium (MTT) assay was used to detect proliferation level.@*Results@#There were 20 cases in the tumor group and metastasis group. There was no significant difference between the two groups in terms of age, sex, time of onset and size of tumors. Flow cytometry showed that the ratio of CD45+EPC in peripheral blood of tumor group and metastasis group was (1.2±0.2)% and (3.1±0.2)% (t=7.823, P<0.001). Correlation analysis showed that the ratio of CD45+EPC was positively correlated with the proliferation index of Ki-67 cells (r=0.592, P=0.006). The results of flow cytometry showed that the mean fluorescence intensity (MFI) of ROS in EPC was 102.1±22.9 in tumor group and 530.0±67.2 in metastasis group (t=6.025,P<0.001). The results of ELISA showed that the mass concentrations of IL-10 and TGF-β in EPC supernatant of tumor group were (10.8±1.6) and (3.2±0.8) μg/L, respectively. The mass concentrations of IL-10 and TGF-beta in EPC supernatant of metastasis group were (26.9±3.7) and (6.4±0.9) μg/L, respectively (t=3.956, P=0.003; t=2.595, P=0.027). Transwell results showed that the proportion of invasive cells in the CD45+EPC group [(40.3±4.4)%] was higher than that in the control group [(17.5±2.2)%] (t=4.607, P=0.001). MTT proliferation experiment showed that the proliferation rate of the CD45+EPC group [(52.0±3.3)%] was higher than that of the control group [(30.5±1.9)%] (t=5.656, P<0.001).@*Conclusions@#The proportion of CD45+EPC in patients with tongue cancer metastasis is significantly increased. CD45+EPC can promote the proliferation and metastasis of tongue cancer by secreting immunosuppressive molecules and ROS.