Expansion of cord blood stem cells in fibronectin-coated microfluidic bioreactor

ABSTRACT Background: Hematopoietic stem/progenitor cell transplantation is the main treatment option for hematological malignancies and disorders. One strategy to solve the problem of low stem cell doses used in transplantation is pre-transplant expansion. We hypothesized that using fibronectin-coated microfluidic channels would expand HSPCs and keep self-renewal potential in a three-dimensional environment, compared to the conventional method. We also compared stem cell homing factors expression in microfluidic to conventional cultures. Materials and methods: A microfluidic device was created and characterized by scanning electron microscopy. The CD133+ cells were collected from cord blood and purified. They were subsequently cultured in 24-well plates and microfluidic bioreactor systems using the StemSpan serum-free medium. Eventually, we analyzed cell surface expression levels of the CXCR4 molecule and CXCR4 mRNA expression in CD133+ cells cultured in different systems. Results: The expansion results showed significant improvement in CD133+ cell expansion in the microfluidic system than the conventional method. The median expression of the CXCR4 in the expanded cell was lower in the conventional system than in the microfluidic system. The CXCR4 gene expression up-regulated in the microfluidic system. Conclusion: Utilizing microfluidic systems to expand desired cells effectively is the next step in cell culture. Comparative gene expression profiling provides a glimpse of the effects of culture microenvironments on the genetic program of HSCs grown in different systems.

Research progress of C-X-C motif chemokine ligand 12 and its receptor signaling axis in the regulation of pulmonary fibrosis / 中华劳动卫生职业病杂志

Pulmonary fibrosis is an irreversible interstitial lung disease characterized by lung parenchyma remodeling and collagen deposition. In recent years, the incidence and mortality of pulmonary fibrosis caused by unknown causes have risen. However, its pathogenesis is still unclear. C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C chemokine receptor 4 (CXCR4)/CXCR7 signal axis plays a critical regulatory role in pulmonary fibrosis disease. In addition, the signal axis has been shown to regulate recruitment and migration of circulating fibrocytes, mesenchymal stem cells to the damage lung tissue, the migration of endothelial cells, the proliferation and differentiation of fibroblasts and endothelial cells, which further affects the occurrence and progression of pulmonary fibrosis. In this review, we summarized the pathogenesis and treatment research progress of CXCL12 and its receptor CXCR4/CXCR7 in the occurrence and progression of pulmonary fibrosis.

Effect and Mechanism of Cxcr4 Gene-Modified BMSC-Derived Exosomes on Aplastic Anemia / 中国实验血液学杂志

OBJECTIVE@#To explore the improvement effect of CXC chemokine receptor 4 (Cxcr4) gene-modified bone marrow mesenchymal stem cell (BMSC)-derived exosomes on aplastic anemia (AA), and make a preliminary exploration of the mechanism.@*METHODS@#Mouse BMSCs were isolated and cultured, then infected by recombinant lentivirus carrying Cxcr4 gene. The expression of green fluorescence was observed through fluorescence microscope, the expression of Cxcr4 mRNA was detected by real-time fluorescence quantitative PCR, and the BMSC-derived exosomes modified with Cxcr4 gene were extracted. Mouse models of AA were constructed, and control group, model group (AA), AA+BMSC group, AA+NC-BMSC group, AA+Cxcr4-BMSC group were set up. Except control group and model group, the other three groups of mice were injected 400 μl exosomes from different sources via the tail vein, after 2 weeks, the routine blood indices and the number of bone marrow nucleated cells were detected, the pathological changes of bone marrow were observed by HE staining, and the expression level of Treg cells was detected by flow cytometry.@*RESULTS@#Mouse BMSCs were successfully isolated, and BMSCs with high expression of Cxcr4 and their exosomes were obtained. Compared with the control group, the number of red blood cell (RBC), white blood cell (WBC), and platelet (PLT), the hemoglobin (Hb) content and proportion of Treg cells in the peripheral blood of mice in the model group significantly decreased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). The proliferation level of nucleated cells was low, and the medullary cavity was filled with a large number of fat cells. Compared with the model group, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+BMSC group, AA+NC-BMSC group, and AA+Cxcr4-BMSC group significantly increased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01), and pathological changes of bone marrow were improved. In addition, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+Cxcr4-BMSC group were significantly higher than those in the AA+BMSC group (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01).@*CONCLUSION@#Injection of Cxcr4 gene-modified BMSC-derived exosomes has a certain improvement effect on AA mice, and the mechanism may be related to an increase of the proportion of Treg cells.

Effect of CXCR4 on the Treatment Response and Prognosis of Carfilzomib in Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To explore the effect of CXCR4 on the treatment response and prognosis of Carfilzomib (CFZ) in multiple myeloma.@*METHODS@#Dataset GSE69078 based on microarray data from two CFZ-resistant MM cell lines and their corresponding parental cell lines (KMS11-KMS11/CFZ and KMS34-KMS34/CFZ) were downloaded from Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified, and Protein-protein interaction (PPI) network was established to identify the key genes involved in CFZ resistance acquisition. Finally, the prognostic roles of the CFZ risistance key genes in MM using MMRF-CoMMpass data study was verified.@*RESULTS@#44 up-regulated and 46 down-regulated DEGs were identified. Top 10 hub genes (CCND1, CXCR4, HGF, PECAM1, ID1, HEY1, TCF4, HIST1H4J, HIST1H2BD and HIST1H2BH) were identified via Protein-protein interaction (PPI) network analysis. The CoMMpass data showed that high CXCR4 expression showed correlation to relative higher relapse and progress rates and the overall survival was significant decreased in high CXCR4 patients (P=0.013).@*CONCLUSION@#CXCR4 perhaps plays a crucial role in CFZ acquired resistance, which might help identifying potential CFZ-sensitive patients before treatment and providing a new therapeutic target in CFZ-resistant MM.

Prospective identification of potential factors influencing stem cell mobilization and the necessity for plerixafor use in newly diagnosed multiple myeloma patients undergoing autologous stem cell transplantation

ABSTRACT Introduction: To study the efficacy and safety of single large volume leukapheresis by using generic G-CSF or G-CSF plus Plerixafor in achieving adequate stem cell yield and various factors influencing thereof in newly diagnosed multiple myeloma patients undergoing autologous stem cell transplant . Method: This prospective study was undertaken among 55 newly diagnosed multiple myeloma patients undergoing autologous stem cell transplant and aged between 18 and 75 years. Mobilization and harvesting of stem cells were performed by using GCSF or GCSF plus Plerixafor and large volume leukapheresis, respectively. A stem cell yield of ≥2 × 106 kg-1 and the number of apheresis procedures were primary efficacy endpoints, while the ideal stem cells yield >5 × 106 kg-1, the engraftment day and D100 response/graft sustainability were secondary endpoints. Result: The primary endpoint was achieved in all cases in both the groups by using a single LVL leukapheresis procedure. Fulfillment of all the secondary endpoints was satisfactory and comparable in both the groups. Age, pre-apheresis CD34+ count and number of interruptions during the LVL were significant factors influencing the stem cell yield (p < 0.05). Adverse drug reactions during the apheresis and post-ASCT period were manageable. Conclusion: The LVL is safe and cost-effective in attaining a minimum of CD34+ cells in a single procedure with manageable adverse reactions. Judicious intervention during the procedure may be helpful in ensuring the adequate yield.

Research Advance of CXCR4 Inhibitors in the Treatment of Acute Myeloid Leukemia--Review / 中国实验血液学杂志

CXCL12/CXCR4 axis composed of chemokine CXCL12 and its specific ligand CXCR4 can regulate and control the adhesion of leukemia cells to protective bone marrow niche, promote cell survival, and resist apoptosis induced by signal transduction inhibitors and chemotherapeutic drugs. Therefore, CXCL12 /CXCR4 axis has become a new target for the treatment of acute myeloid leukemia. At present, CXCR4 inhibitors that have been developed are in different clinical trials, showing good anti-leukemia effect. In this review, the research advance of CXCR4 inhibitors in the treatment of acute myeloid leukemia is summarized briefly.

Pro-pigmentary action of 5-fluorouracil through the stimulated secretion of CXCL12 by dermal fibroblasts / 中华医学杂志(英文版)

BACKGROUND@#There is growing evidence that 5-fluorouracil (5-FU) combined with therapeutic trauma can effectively induce skin repigmentation in vitiligo patients who are unresponsive to conventional treatments. Previous studies have mainly focused on identifying the antimitotic activity of 5-FU for the treatment of skin cancer, but few studies have investigated its extra-genotoxic actions favoring melanocyte recruitment.@*METHODS@#We utilized the full thickness excisional skin wound model in Dct-LacZ transgenic mice to dynamically assess the migration of melanocytes in the margins of wounds treated with or without 5-FU. The in-situ expression of CXCL12 was examined in the wound beds using immunofluorescence staining. Quantitative real-time polymerase chain reaction and Western blotting analyses were performed to detect the expression levels of CXCL12 mRNA and protein in primary mouse dermal fibroblasts treated with or without 5-FU. Transwell assays and fluorescein isothiocyanate (FITC)-phalloidin staining were used to observe cell migration and filamentous actin (F-actin) changes of melan-a murine melanocytes.@*RESULTS@#Whole mount and cryosection X-gal staining showed that the cell numbers of LacZ-positive melanocytes were much higher in the margins of dorsal and tail skin wounds treated with 5-FU compared with the controls. Meanwhile, CXCL12 immunostaining was significantly increased in the dermal compartment of wounds treated with 5-FU (control vs. 5-FU, 22.47 ± 8.85 vs. 44.69 ± 5.97, P < 0.05). Moreover, 5-FU significantly upregulated the expression levels of CXCL12 mRNA (control vs. 5-FU, 1.00 ± 0.08 vs. 1.54 ± 0.06, P < 0.05) and protein (control vs. 5-FU, 1.00 ± 0.06 vs. 2.93 ± 0.10, P < 0.05) in cultured fibroblasts. Inhibition of the CXCL12/CXCR4 axis suppressed melanocyte migration in vitro using a CXCL12 small interfering RNA (siRNA) or a CXCR4 antagonist (AMD3100).@*CONCLUSION@#5-FU possesses a pro-pigmentary activity through activation of the CXCL12/CXCR4 axis to drive the chemotactic migration of melanocytes.

Correlation between Expression of CXCL12, CXCR4, VEGF, MVD and Prognosis in Patients with Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To investigate the expressions of stromal cell-derived factor (CXCL12), stromal cell-derived factor receptor (CXCR4), vascular endothelial growth factor (VEGF) and microvessel density (MVD) in bone marrow microsputum of patients with multiple myeloma (MM) and their correlation with the prognosis.@*METHODS@#The expressions of CXCL12, CXCR4, VEGF and MVD in bone marrow microtubules of 57 newly diagnosed MM patients and 26 normal bone marrow samples were detected by immunohistochemistry. The rank sum test was used to compare the differences between the two groups. The clinical data of the patients were collected to analyze the correlation between the indicators of the MM group and the prognosis.@*RESULTS@#The expressions of CXCL12, CXCR4, VEGF and MVD in the bone marrow biopsy of the patients in MM group were significantly higher than those in the normal control group (P＜0.05). The expressions levels of CXCL12, CXCR4, VEGF and MVD were in the bone marrow of the patients in MM group were correlated with the ISS stage, risk stratification and the proportion of plasma cells in the bone marrow (P＜0.05). Univariate analysis showed that age, ISS stage, risk stratification, plasma cell ratio, expressions of CXCL12, CXCR4, VEGF, and MVD associated with the prognosis of patients with MM (P＜0.05). Multivariate analysis found that expressions of CXCR4, VEGF, MVD, age, and plasma cell ratio were independent prognostic factors.@*CONCLUSION@#The expressions of CXCL12, CXCR4, VEGF and MVD are increase in the bone marrow of patients with multiple myeloma, and their expressions levels are associate with the occurrence and development of multiple myeloma, and their high expression may indicate a poor prognosis.

Effect of chronic emotional stress induced by empty bottle stimulation on inflammatory factors in rats with acute myocardial infarction: analysis of the CXCL12/CXCR4 axis / 南方医科大学学报

OBJECTIVE@#To investigate the effect of chronic emotional stimulation induced by empty bottle stimulation on CXCL12/CXCR4-mediated inflammatory response in rats with acute myocardial infarction (AMI).@*METHODS@#Rat models of anxiety were established by a 21-day stimulation with uncertain empty bottle drinking water, and myocardial infarction was induced by ligating the left anterior descending branch of the coronary artery; compound models were established by performing myocardial infarction operation on the 15th day of anxiety modeling. The rats were randomly divided into 4 groups: shamoperated group (=6), myocardial infarction group (=6), compound model group (with myocardial infarcted and anxiety; = 6), and inhibitor group (compound models treated daily with 1 mg/kg AMD3100 for 6 days; =7). Echocardiography was used to examine the LVEF and LVFS to evaluate the cardiac function of the rats. Elevated maze test and open field test were used to evaluate the behaviors of the rats. The expressions of CXCL12, CXCR4, IL-1β, IL-18 and neutrophil active protease (NE) in the myocardial tissues and blood samples were detected with ELISA and immunohistochemistry.@*RESULTS@#The LVEF and LVFS were lower in the compound model group than in the sham group and myocardial infarction group ( < 0.05), and were higher in inhibitor group than in the compound model group ( < 0.05). LVID; d and LVID; s were lower in the inhibitor group than in the compound model group ( < 0.05). Compared to those in the sham group and myocardial infarction group, the rats in the compound model group more obviously preferred to stay in the closed arm ( < 0.05) in EPM; the rats in the inhibitor group had more times of entering and staying in the open arm than the compound model rats ( < 0.05); the horizontal and vertical movements were less in the compound model rats than in those in the sham group and the myocardial infarction group ( < 0.05) in OFT, and the vertical movement of the rats in inhibitor group was higher than those in the compound model group ( < 0.05). The expression of CXCR4 in the marginal zone of myocardial infarction was significantly higher in the compound model group than in the sham-operated group, myocardial infarction group and inhibitor group ( < 0.05). The expressions of IL-1β, IL-18 and NE in the inhibitor group were significantly lower than those in the compound model group ( < 0.05). Compared with at in the sham-operated group, the number of Nissl bodies in the compound model group decreased significantly ( < 0.01).@*CONCLUSIONS@#Chronic emotional stress induced by empty bottle stimulation can lead to dysfunction of the CXCL12/CXCR4 axis, which causes inflammatory cascade after myocardial infarction to worsen myocardial cell necrosis, cardiac function and hippocampal neuronal damage after the infarction.

Inibição da replicação do influenza através da modulação de fatores restritivos pelos ligantes dos receptores CCR5 e CXCR4 / Inhibition of influenza replication through modulation of restrictive factors by CCR5 and CXCR4 receptor ligands

Dados da Organização Mundial da Saúde (OMS) mostram que a gripe é uma doença que afeta com gravidade de 3 a 5 milhões de pessoas em todo o mundo promovendo, anualmente, de 290 a 650 mil mortes. A gravidade da doença pode ser ainda maior quando surgem cepas pandêmicas, para as quais a população tem pouca ou nenhuma imunidade. Portanto, os vírus influenza são considerados os principais agentes virais causadores de infecções respiratórias agudas e tem grande importância epidemiológica. Durante a infecção por influenza, o interferon liberado na resposta imune inata induz cascatas de sinalizações intracelulares, levando a expressão de diferentes genes. Muitos desses genes codificam proteínas nas células, incluindo os fatores de restrição (FRs). É largamente descrito na literatura que os FRs presentes nas células do hospedeiro são proteínas antivirais, que atuam sobre a replicação de diversos vírus, prejudicando o ciclo infeccioso desses patógenos. Nosso grupo já observou que uma proteína do HIV-1, gp120, é capaz de inibir a replicação do vírus influenza A(H1N1)pdm09. Sendo assim, visamos investigar se ligantes dos receptores CCR5 (R5) e CXCR4 (X4) poderiam modular fatores restritivos de forma a inibir a replicação do vírus influenza. Para isso, células A549 foram expostas aos ligantes endógenos dos receptores R5 e X4, CCL3, CCL4, CCL5, CXCL12 ou exógenos, gp120 R5-trópicos e gp120 X4-trópicos. Então, as células foram infectadas com o vírus A/H3N2 com MOI 2 por 1h. Após 24 h, o título viral foi avaliado por RT-PCR em tempo real. A monocamada celular foi exposta aos ligantes de R5 e lisada para avaliação dos níveis de RNAm de diferentes FRs, utilizando um painel. Em seguida, as células A549 foram expostas aos ligantes de R5 e lisadas para a quantificação do nível proteico do FR SAMHD1 por immunoblotting

Realizamos também um ensaio funcional no qual células A549 sofreram knockdown para SAMHD1 e foram infectadas com o A/H3N2. Adicionalmente, as células foram tratadas com guanosina para avaliar o papel regulatório de dNTPs por SAMHD1. Nossos resultados mostraram que a exposição aos ligantes endógenos e exogenos inibiram a replicação do vírus influenza em torno de 50%, em células A549. Através do painel de RNAm para FRs, observamos aumento de 4X dos transcritos para o FR SAMHD1. Observamos também que os ligantes de R5 aumentaram o conteúdo proteico de SAMHD1 em até 3X. Com o experimento funcional de knockdown, observamos que a diminuição dos níveis proteicos de SAMHD1 leva ao aumento da replicação viral, no modelo utilizado. O tratamento com guanosina em células expostas aos ligantes de R5 inibiu ainda mais a replicação do vírus influenza, sugerindo que o mecanismo inibitório possa ser mediado pela ativação da atividade de desoxinucleotídeo trifosfohidrolase de SAMHD1. Sendo assim, nossos dados mostram pela primeira vez uma relação direta de SAMHD1 com inibição da replicação do influenza, além disso, traz perspectivas para novos estudos sobre a modulação de sinalizações, através de receptores celulares, para induzir proteínas de grande importância no controle de infecções virais relevantes para a saúde pública. (AU)

Hyperbaric oxygen improves functional recovery of rats after spinal cord injury via activating stromal cell-derived factor-1/CXC chemokine receptor 4 axis and promoting brain-derived neurothrophic factor expression / 中华医学杂志(英文版)

BACKGROUND@#Spinal cord injury (SCI) is a worldwide medical concern. This study aimed to elucidate the mechanism underlying the protective effect of hyperbaric oxygen (HBO) against SCI-induced neurologic defects in rats via exploring the stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor 4 (CXCR4) axis and expression of brain-derived neurotrophic factor (BDNF).@*METHODS@#An acute SCI rat model was established in Sprague-Dawley rats using the Allen method. Sixty rats were divided into four groups (n = 15 in each group): sham-operated, SCI, SCI treated with HBO (SCI + HBO), and SCI treated with both HBO and AMD3100 (an antagonist of CXCR4; SCI + HBO + AMD) groups. The rats were treated with HBO twice a day for 3 days and thereafter once a day after the surgery for up to 28 days. Following the surgery, neurologic assessments were performed with the Basso-Bettie-Bresnahan (BBB) scoring system on postoperative day (POD) 7, 14, 21, and 28. Spinal cord tissues were harvested to assess the expression of SDF-1, CXCR4, and BDNF at mRNA and protein levels, using quantitative real-time polymerase chain reaction, Western blot analysis, and histopathologic analysis.@*RESULTS@#HBO treatment recovered SCI-induced descent of BBB scores on POD 14, (1.25 ± 0.75 vs. 1.03 ± 0.66, P < 0.05), 21 (5.27 ± 0.89 vs. 2.56 ± 1.24, P < 0.05), and 28 (11.35 ± 0.56 vs. 4.23 ± 1.20, P < 0.05) compared with the SCI group. Significant differences were found in the mRNA levels of SDF-1 (mRNA: day 21, SCI + HBO vs. SCI + HBO + AMD, 2.89 ± 1.60 vs. 1.56 ± 0.98, P < 0.05), CXCR4 (mRNA: day 7, SCI + HBO vs. SCI, 2.99 ± 1.60 vs.1.31 ± 0.98, P < 0.05; day 14, SCI + HBO vs. SCI + HBO + AMD, 4.18 ± 1.60 vs. 0.80 ± 0.34, P < 0.05; day 21, SCI + HBO vs. SCI, 2.10 ± 1.01 vs.1.15 ± 0.03, P < 0.05), and BDNF (mRNA: day 7, SCI + HBO vs. SCI, 3.04 ± 0.41 vs. 2.75 ± 0.31, P < 0.05; day 14, SCI + HBO vs. SCI, 3.88 ± 1.59 vs. 1.11 ± 0.40, P < 0.05), indicating the involvement of SDF-1/CXCR4 axis in the protective effect of HBO.@*CONCLUSIONS@#HBO might promote the recovery of neurologic function after SCI in rats via activating the SDF-1/CXCR4 axis and promoting BDNF expression.

Effect of triptolide in improving platelet activation in patients with ankylosing spondylitis by regulating VEGFA,SDF-1,CXCR4 pathway / 中国中药杂志

The effect of triptolide( TP) on VEGFA,SDF-1,CXCR4 pathway were investigated in vitro to explore the mechanism in improving platelet activation in patients with ankylosing spondylitis( AS). Peripheral blood mononuclear cells( PBMC) were used for the experiment and divided into 4 groups: normal group( NC),model group( MC),triptolide group( TP),and AMD3100 group. The optimal concentration of TP was measured by the MTT method. The expressions of TNF-α,IL-1β,IL-4,IL-10,VEGFA and VEGFR were detected by ELISA. The expressions of SDF-1,CXCR4 and VEGFA were detected by real-time quantitative PCR( RT-qPCR).The expressions of SDF-1,CXCR4,VEGFA and VEGFR were detected by Western blot. The expression levels of CD62 p,CD40 L and PDGFA were detected by immunofluorescence. MTT results showed that medium-dose TP had the strongest inhibitory effect on cells at24 h. The results of ELISA and PCR showed that TP inhibited mRNA expressions of IL-1β,TNF-α,VEGFA,VEGFR and SDF-1,CXCR4 and VEGFA. The results of Western blot indicated that TP inhibited SDF-1,CXCR4 and VEGFA,VEGFR protein expressions; immunofluorescence results indicate that TP can inhibit the expressions of CD62 p,CD40 L,PDGFA. TP may regulate platelet activation by down-regulating SDF-1,CXCR4,VEGFA and VEGFR mRNA expressions,thereby down-regulating IL-1β and TNF-αexpressions,and up-regulating the expressions of IL-4 and IL-10 cytokines.

Role of endocytosis in cell surface CXC chemokine receptor 4 expression of stem cells from apical papilla / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the change of cell surface CXC chemokine receptor 4 (CXCR4) expression of stem cells from apical papilla (SCAP) after the inhibition of endocytotic pathway, thus to provide experimental basis for the mechanism of SCAP migration.@*METHODS@#The immunofluorescence analysis was conducted to examine the co-expression of CXCR4 and endocytotic compartments, including early endosomes, recycling endosomes and lysosomes in SCAP. Several Rab proteins were applied as markers of organelles in the endocytotic pathway, including Rab5 for early endosomes, Rab11A for recycling endosomes, and Lamp1 for lysosomes. The co-localization of CXCR4 with these endodontic compartments was further observed by proximity ligation assay (PLA). SCAP was treated with two kinds of endocytotic inhibitors, Blebbistatin and Dynasore, at a concentration of 80 μmol/L, respectively. The conditioning time was 1 hour. Flow cytometry was carried out to evaluate the proportion of SCAP that expressed CXCR4 on cell surface. The data were analysed by analysis of variance (ANOVA).@*RESULTS@#The red staining of CXCR4 on immunofluorescence confocal microscopy predominantly overlapped with the green staining of Rab5 and Rab11A, and partly overlapped with Lamp1. It indicated that most CXCR4 molecules were located in early endosomes and recycling endosomes, and some were located in lysosomes. The PLA results revealed that the co-localizaiton of CXCR4 with endocytotic compartments could be observed in early endosomes, recycling endosomes and lysosomes. According to the results of flow cytometry, the proportion of SCAP that expressed CXCR4 on cell surface was as low as 0.13%±0.10%. After the inhibition of endocytosis by pretreating the cells with the following two inhibitors, Blebbistatin and Dynasore, the percentage of SCAP that positively expressed CXCR4 on cell surface was significantly increased to 13.34%±1.31% in Blebbistatin group and 4.03%±0.92% in Dynasore group (F=16.721, P<0.001). Moreover, the number of SCAP that expressed CXCR4 on cell surface in Blebbistatin group was significantly higher than that in Dynasore group (P<0.001).@*CONCLUSION@#The inhibition of endocytotic pathway could increase the number of SCAP that expressed CXCR4 on cell surface, and provide potency for the migration of SCAP.

Diagnóstico tardío de síndrome WHIM / Late diagnosis of WHIM sydrome

El síndrome WHIM es una inmunodeficiencia primaria de herencia autosómica dominante, debida a mutaciones en el gen CXCR4, que se caracteriza por verrugas cutáneo-mucosas, hipogammaglobulinemia, infecciones bacterianas recurrentes y mielocatesis. El tratamiento se basa en el uso de antibióticos profilácticos, gammaglobulina en dosis sustitutiva y factores estimulantes de colonias de granulocitos o de granulocitos y macrófagos, en forma crónica. Presentamos el caso de una mujer de 21 años que comenzó a los 10 meses de edad con leucopenia y al siguiente año múltiples infecciones con hipogammaglobulinemia requiriendo gammaglobulina endovenosa durante los episodios. Evolucionó con neutropenia crónica. Una punción aspiración de médula ósea mostró la serie mieloide aumentada con ligero predominio de elementos inmaduros. El cuadro fue interpretado como inmunodeficiencia común variable debido a la asociación de múltiples cuadros infecciosos, niveles disminuidos de IgG, IgM e IgA y linfopenia con disminución de linfocitos B de memoria, por lo que comenzó tratamiento sustitutivo con gammaglobulina endovenosa más antibióticos profilácticos. A los 20 años se registraron pequeñas verrugas en manos que progresaron hacia antebrazos, abdomen, cara y rodillas. Se realizaron estudios moleculares para la búsqueda de mutaciones en el gen CXCR4 donde se detectó la mutación p.Arg334STOP en estado heterocigota confirmando el diagnóstico de síndrome WHIM, que es una inmunodeficiencia infrecuente y de difícil diagnóstico.

WHIM syndrome is a primary autosomal dominant immuno deficiency due to CXCR4 mutations characterized by mucocutaneous warts, hypogammaglobulinemia, recurrent bacterial infections and myelokathesis. Treatment consists in prophylactic antibiotics, immunoglobulin replacement and granulocyte or granulocyte/monocyte colony stimulating factors. We present the case of a 21 year old woman who showed leukopenia at 10 months of age and one year later multiple infections with hypogammaglobulinemia requiring intravenous immunoglobulin. During follow up she developed chronic neutropenia. A bone marrow aspiration showed increased myeloid series with predominance of immature elements. On the basis of infections, low levels of IgG, IgA, IgM and lymphopenia with absent memory B cells, a diagnosis of common variable immunodeficiency was made. She started intravenous immunoglobulin replacement and prophylactic antibiotics. At age 20, small warts in hands that progressed to forearms, knees, abdomen and face were recorded. CXCR4 gene sequencing was done detecting a heterozygous p.Arg334STOP mutation, confirming WHIM syndrome. This disease is infrequent and difficult to diagnose.

Effects of concentrated growth factors on the angiogenic properties of dental pulp cells and endothelial cells: an in vitro study

Abstract The aim was to investigate the angiogenic effects of concentrated growth factors on human dental pulp cells and human umbilical vein endothelial cells. Cells were treated with concentrated growth factor extracts. The CCK-8 assay and cell cycle assay were conducted to evaluate cell growth. Cell migration was evaluated by the Transwell migration assay. Angiogenesis-associated mRNA and protein expression levels were determined using quantitative real-time PCR and Western blotting, respectively. A tube formation assay was conducted to evaluate the angiogenic capacity in vitro. The data showed that compared with the control, concentrated growth factor extracts significantly promoted dental pulp cell proliferation and differentiation and endothelial cell proliferation and migration in a dose-dependent manner (p < 0.05). Concentrated growth factor extracts also promoted the tube-like structure formation of endothelial cells in vitro. The RT-PCR and Western blot results showed that concentrated growth factor extracts upregulated the expression of angiogenesis-related genes - chemokine receptor-4, platelet-derived growth factor, and vascular endothelial growth factor - in dental pulp cells. In conclusion, concentrated growth factors showed proangiogenic effects on dental pulp cells and endothelial cells and have good application potential for dental pulp revascularization.

The CXCL12 (SDF-1)/CXCR4 chemokine axis: Oncogenic properties, molecular targeting, and synthetic and natural product CXCR4 inhibitors for cancer therapy / 中国天然药物

Chemokine 12 (CXCL12), also known as stromal cell derived factor-1 (SDF-1) and a member of the CXC chemokine subfamily, is ubiquitously expressed in many tissues and cell types. It interacts specifically with the ligand for the transmembrane G protein-coupled receptors CXCR4 and CXCR7. The CXCL12/CXCR4 axis takes part in a series of physiological, biochemical, and pathological process, such as inflammation and leukocyte trafficking, cancer-induced bone pain, and postsurgical pain, and also is a key factor in the cross-talking between tumor cells and their microenvironment. Aberrant overexpression of CXCR4 is critical for tumor survival, proliferation, angiogenesis, homing and metastasis. In this review, we summarized the role of CXCL12/CXCR4 in cancer, CXCR4 inhibitors under clinical study, and natural product CXCR4 antagonists. In conclusion, the CXCL12/CXCR4 signaling is important for tumor development and targeting the pathway might represent an effective approach to developing novel therapy in cancer treatment.

Association of CXCL12/CXCR4 gene polymorphisms with genetic risk and severity of coronary stenosis in patients with coronary artery disease / 浙江大学学报·医学版

OBJECTIVE@#To investigate the association of CXCL12 and CXCR4 polymorphisms with the genetic risk and severity of coronary stenosis in patients with coronary artery disease (CAD).@*METHODS@#Competitive allele specific PCR(KASP) was performed to identify the genotypes of rs2297630 and rs2322864 polymorphisms in 302 CAD patients and 302 age-and gender-matched healthy controls. The severity of CAD patients was assessed by the Gensini scoring system according to the results of coronary arteriography. The association of rs2297630 and rs2322864 polymorphisms with genetic risk of CAD and Gensini scores were analyzed by unconditional logistic regression and multivariate linear regression respectively.@*RESULTS@#There were significant differences in the genotype and allele frequencies of both rs2297630 and rs2322864 between the CAD group and healthy control (all 0.05).@*CONCLUSIONS@#Gene polymorphism of CXCL12 rs2297630 is associated with the genetic risk of CAD and the severity of coronary stenosis. Moreover, the gene polymorphism of CXCR4 rs2322864 is associated with genetic risk of CAD, but not with the severity of coronary stenosis.

Mechanism of EGFR Over-expression and Mutations Leading to Biological Characteristics Changes of Human Lung Adenocarcinoma Cells through CXCR4/CXCL12 Signaling Pathway / 中国肺癌杂志

BACKGROUND@#The epidermal growth factor receptor (EFGR) mutation was closely related to the invasion and metastasis of lung adenocarcinoma and the biological axis of CXCR4/CXCL12 (chemokine receptor 4/chemokine ligand 12) played an important role in the organ-specific metastasis of the tumor. It was a question surrounding whether there is interaction between them in the process of lung adenocarcinoma metastasis. To investigate the potential molecular mechanisms of EGFR over-expression and EFGR-mutations effects on cell proliferation, migration and invasion, we constructed EGFR over-expression and three EFGR-mutant human lung adenocarcinoma H1299 cell sublines.@*METHODS@#EGFR over-expression and three EFGR-mutant (EGFR-E746-A750del, EGFR-T790M and EGFR-L858R) plasmid were designed and transfected H1299 cells with Lipofectamine 2000. H1299 cells transfected with empty vector were negative control (NC), and H1299 cells without transfection were set as blank control (BC). The effects of EGFR over-expression and mutations on the proliferation, migration and invasion of H1299 cells were detected by cell cloning assay, wound healing assay and Transwell assay. The mRNA and protein expression levels of MMP-2, MMP-9, CXCR4 and CXCL12 were detected by RT-PCR and Western blot.@*RESULTS@#Compared with negative control group and blank control group, EGFR over-expression and EGFR-E746-A750 deletion have significantly higher colony formation (28±2, 28.33±4.16; respectively) (P<0.05) and the cell migration and invasion ability were significantly increased (P<0.05). RT-PCR and Western blot assay showed that the mRNA and protein expression of MMP-2, MMP-9, CXCR4 and CXCL12 in EGFR over-expression and EGFR-E746-A750 deletion group were remarkably higher than that in negative control and blank control group (P<0.05).@*CONCLUSIONS@#EGFR over-expression and 19 exon deletion can promote the expression of MMP-2 and MMP-9 by up-regulating CXCR4/CXCL12 signaling pathway, leading to the change of tumor biological characteristics such as higher proliferation, migration and invasion ability.