The purpose of this study was to devise an expanded ischemic flap model and to investigate the role of AMD-3100 (Plerixafor, chemokine receptor 4 inhibitor) in this model by confirming its effect on mobilization of stem cells from the bone marrow. Male Sprague-Dawley rats were used as an animal research model. The mobilization of stem cells from the bone marrow was confirmed in the AMD-3100-treated group. The fractions of endothelial progenitor cells (EPC) and the vascular endothelial growth factor receptor (VEGFR) 2+ cells in the peripheral blood were increased in groups treated with AMD-3100. The expression of vascular endothelial growth factor (VEGF) was increased in response to expansion or AMD injection. The expression of stromal cell derived factor (SDF)-1 and VEGFR2 were increased only in unexpanded flap treated with AMD-3100. Treatment with AMD-3100 increased both the number and area of blood vessels. However, there were no statistically significant differences in the survival area or physiologic microcirculation in rats from the other groups. This endogenous neovascularization induced by AMD-3100 may be a result of the increase in both the area and number of vessels, as well as paracrine augmentation of the expression of VEGF and EPCs. However, the presence of a tissue expander under the flap could block the neovascularization between the flap and the recipient regardless of AMD-3100 treatment and expansion.
Animals ; Anti-HIV Agents/pharmacology ; Bone Marrow Cells/cytology ; Chemokine CXCL12/biosynthesis ; Endothelial Progenitor Cells/*cytology ; Hematopoietic Stem Cells/*cytology ; Heterocyclic Compounds/*pharmacology ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism ; Male ; Neovascularization, Physiologic ; Nitric Oxide Synthase Type III/metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, CXCR4/antagonists & inhibitors ; Surgical Flaps/*blood supply/surgery ; Tissue Expansion/*methods ; Vascular Endothelial Growth Factor A/biosynthesis ; Vascular Endothelial Growth Factor Receptor-2/biosynthesis/metabolism

OBJECTIVETo obtain a specific antagonist of CXCR4, SDF-1P2G54 by mutating SDF-1 second proline (P) into glycin (G) and removing the α-helix of its C-terminal.

METHODSSDF-1p2g54 gene amplified by PCR was inserted into the vector pET-30a (+) and transformed into Escherichia coli (E. coli) strain BL21. After IPTG induction of E. coli, the expressed recombinant protein was purified with nickel-affinity chromatography column under denaturing conditions and refolded with gradient dilution and ultra-filtration. The chemotactic effect of SDF-1P2G54 on Jurkat cells and its antagonistic effect against SDF-1 were determined by transwell assay; flow cytometry was used to assay the ability of SDF-1P2G54 to induce calcium influx and CXCR4 internalization in MOLT4 cells.

RESULTSThe recombinant protein SDF-1P2G54 completely lost the functions to activate CXCR4 or to induce transmembrane migration of Jurkat cells and calcium influx in MOLT4 cells, but maintained a high affinity to CXCR4. SDF-1P2G54 effectively inhibited the chemotactic effect of wild-type SDF-1 to Jurkat cells, and induced rapid CXCR4 internalization in MOLT4 cells.

CONCLUSIONSDF-1P2G54 is a new antagonist of CXCR4 with a potential value as an effective inhibitor of HIV-1 infection, cancer metastasis or other major diseases.

Cell Line ; Chemokines, CXC ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Humans ; Mutant Proteins ; biosynthesis ; genetics ; Receptors, CXCR4 ; antagonists & inhibitors ; Recombinant Proteins ; biosynthesis ; genetics

This study was amied to construct CXCR4 gene modified bone marrow mesenchymal stem cells (MSCs), and investigate the effect of CXCR4 expression on MSCs migration. The retrovirus vector pMSCV-CXCR4-IRES-GFP that expresses human CXCR4 gene was cloned,the MSCs were transduced by the virus, and the expression of OXCR4 was analyzed by FACS, RT-PCR and immunofluorescence staining. The migration assay was performed using Transwell method in the presence of SDF-1. FACS results showed that 46% of the transduced MSCs were CXCR4 positive, and 57% were GFP positive. The expression of CXCR4 in MSCs was also confirmed by RT-PCR and immunostaining. The migration of MSCs was induced by SDF-1 and was strongly dependent on CXCR4 expression. The concentration of SDF-1 had effect on the migration and the transmigration rate of CXCR4 modified; the amount of MSCs was 5-fold higher than that of untransduced MSCs when the optimal concentration rose to 50 ng/ml. These data indicate that SDF-1/CXCR4 plays an important role in MSCs migration ,and the CXCR4 genetic modification approach could be applied to enhance cell homing, and engraftment in MSCs therapy.
Bone Marrow Cells ; cytology ; Cell Movement ; Cells, Cultured ; Chemokine CXCL12 ; pharmacology ; Genetic Vectors ; genetics ; Humans ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Receptors, CXCR4 ; biosynthesis ; genetics ; Retroviridae ; genetics ; metabolism ; Transduction, Genetic ; Transfection

OBJECTIVETo evaluate the application of CXC chemokine receptor-4 (CXCR4) combined with alpha-methylacyl-CoA racemase (P504S) or P63 protein in the differential diagnosis of benign and malignant prostatic diseases.

METHODSThe EnVision immunohistochemical method was used to detect the expressions of CXCR4, P504S and P63 protein in 40 specimens of PCa not treated by any anticancer therapy and 30 specimens of BPH tissues. The correlation was analyzed between CXCR4 expression and the characteristics of PCa metastasis.

RESULTSOf the 40 cases of PCa, 33 (82.5%) were stained positive for CXCR4, 37 (92.5%) for P504S and 2 (5%) for P63 protein. Of the 30 cases of BPH, 5 (16.6%) exhibited positivity for CXCR4, 1 for P504S and all for P63. P504S + P63 showed a higher rate of correct diagnosis of PCa than either CXCR4 + P63 or P504S + CXCR4. There was a statistically significant correlation between CXCR4 expression and cancer metastasis (P < 0.05).

CONCLUSIONP504S, CXCR4 and P63 are useful tumor markers for the diagnosis and differentiation of benign and malignant prostatic diseases. CXCR4 gives a high rate of correct diagnosis when combined with P504S or P63, and has an important application value in the differential diagnosis of benign and malignant prostatic diseases.

Aged ; Aged, 80 and over ; Biomarkers, Tumor ; biosynthesis ; Diagnosis, Differential ; Humans ; Male ; Membrane Proteins ; biosynthesis ; Middle Aged ; Prostatic Hyperplasia ; diagnosis ; metabolism ; pathology ; Prostatic Neoplasms ; diagnosis ; metabolism ; pathology ; Racemases and Epimerases ; biosynthesis ; Receptors, CXCR4 ; biosynthesis

OBJECTIVETo suppress the expression of CCR5 and CXCR4, the co-receptors for human immunodeficiency virus type 1 ( HIV-1), and thus inhibit HIV-1 from entering cells.

METHODSDNA fragments encoding either CCR5 or CXCR4 were amplified from healthy human peripheral blood mononuclear cells (PBMCs) by reverse transcript polymerase chain reaction (RT-PCR) and sequencing was performed. Correct fragments were inserted into Shuttle plasmid inversely, which was recombined with backbone plasmid containing homologous adenoviral genome in E. coli BJ5183. The recombinant plasmids were transfected into 293 cells in which they were packaged and amplified. Recombinant adenoviruses containing antisense RNA of CCR5 or CXCR4 were obtained and identified by RT-PCR, and the titres of them were determined by cytopathic effect (CPE) method. The U937 and MT4 cells were infected by recombinant adenoviruses containing antisense RNA of CCR5 (multiplicity of infection, MOI = 100) and CXCR4 (MOI = 200), respectively. The expression of co-receptors on infected cell was measured by fluorescence activated cell sorter at 24, 48, 72 hours and 10 days after infection. In addition, the chemotactic activity and proliferation of infected cells were detected with Boyden chamber and 3H incorporation respectively.

RESULTSWe constructed the recombinant plasmids and obtained the recombinant adenoviruses which contained antisense RNA of CCR5 or CXCR4 and were designated as pAd-antiR5 and pAd-antiX4 respectively. The titers of recombinant adenoviruses pAd-antiR5 and pAd-antiX4 were 5 x 10" PFU/ml and 7 x 10(10) PFU/ml, respectively. The expression rate of CCR5 on U937 cells decreased from 82. 10% (blank control) to 1.12% (Ad-antiR5 infected) , and that of CXCR4 on MT4 cells decreased from 42% (blank control) to 1.03% (Ad-antiX4 infected) 24 hours later. The expression rates of CCR5 on Ad-antiR5 infected U937 cells were 1.02% , 1.26% , 1.23% at 48 hours, 72 hours, and 10 days later, respectively. The expression rates of CXCR4 on Ad-antiX4 infected MT4 cells were 1.13%, 1.17%, 1.22% at 48 hours, 72 hours, and 10 days later, respectively. Moreover, the recombinant adenovirus had no effects on chemotactic activity and proliferation of the cells.

CONCLUSIONThe recombinant adenovirus containing antisense CCR5 or CXCR4 can remarkably decrease the expression of co-receptors for HIV-1 on U937 or MT4 cells without affecting their chemotactic activities and proliferative abilities.

Adenoviridae ; genetics ; Cell Line, Transformed ; Cell Proliferation ; Chemotaxis ; Down-Regulation ; Genetic Vectors ; Humans ; RNA, Antisense ; genetics ; RNA, Messenger ; genetics ; Receptors, CCR5 ; biosynthesis ; genetics ; Receptors, CXCR4 ; biosynthesis ; genetics ; Transfection ; U937 Cells

This study was purposed to explore the effect of different cytokine combinations on the expansion of the mononuclear cells drived from umbilical cord blood (CB) ex vivo and expression of CXCR4 and CD49d on CD34+ cells after expansion. Human fresh CB mononuclear cells were cultured in serum-free and stroma-free medium containing different combinations of cytokine for 7 days. At day o and 7, the total cells were counted, CD34+ cells and CD34+CXCR4+, CD34+CD49d+ cells were assayed by flow cytometry, and CFU were determined. According to the different combinations of cytokine, experiments were divided into four groups: control, SF group (SCF + FL), SFT group (SCF + FL + TPO) and SFT6 group (SCF + FL + TPO + IL-6). The results showed that the SF (SF group) combination supported only low expansion of total cells, CD34+ cells and CFU. The addition of TPO in SF group restored UCB stem/progenitors expansion to a higher level than that in SF group, while there was no difference between groups SFT and SFT6 (P > 0.05). The cytokine combinations in groups SF, SFT and SFT6 all could upregulate the expression levels of CD49d and CXCR4 on expanded cord blood CD34+ cells, but there were no significant differences between groups SF, SFT and SFT6 (P > 0.05). It is concluded that SCF + FL has no strong synergistic effects on primitive hematopoietic cells. TPO plays an important role in enhancing expansion of umbilical cord blood hematopoietic cells, while IL-6 only shows a neutral effect on it. SCF + FL + TPO combination not only promotes progenitor cells expansion but also upregulates the expression of CD49d and CXCR4 on CD34+ cells from cord blood.
Antigens, CD34 ; biosynthesis ; genetics ; Cytokines ; pharmacology ; Drug Synergism ; Fetal Blood ; cytology ; Humans ; Integrin alpha4 ; biosynthesis ; genetics ; Leukocytes, Mononuclear ; cytology ; Membrane Proteins ; pharmacology ; Receptors, CXCR4 ; biosynthesis ; genetics ; Stem Cell Factor ; pharmacology ; Thrombopoietin ; pharmacology

The study was aimed to explore the expression of stromal cell derived factor-1alpha (SDF-1alpha) and its receptor CXCR4, and their relationship with the extramedullary infiltration in acute lymphoblastic, grannulocytic and monocytic leukemia. 66 cases of acute leukemia included 31 cases of acute lymphoblatic leukemia (ALL), 20 cases of acute grannulocytic leukemia (M(2)) and 15 cases of acute monocytic leukemia (M(4)+M(5)). There were 41 cases with extramedullary infiltration and 25 cases without-extramedullary infiltration. Enzyme-linked immunoabsorbent assay (ELISA) and flow cytometry were used to determine expression of SDF-1alpha and CXCR4 respectively on leukemia cells in peripheral blood and bone marrow of different groups. The results showed that average plasma level of SDF-1alpha in the ALL, M(4)+M(5), M(2) patients and the normal control were 1317.87 +/- 220.76, 1339.79 +/- 187.06, 1063.70 +/- 190.74, 1908.34 +/- 135.55 (pg/ml) respectively. The average levels in the ALL, M(4)+M(5) and M(2) patients groups were lower than those in normal control group. Both levels in ALL and M(4)+M(5) patient groups were higher than that in M(2) patient group. The average levels of SDF-1alpha in patient group with extramedullary infiltration and patient groups without-extramedullary infiltration were 1252.49 +/- 263.12, 1234.91 +/- 185.50 (pg/ml) respectively. The former seemed as if higher than the latter, but without statistical significance. The MFI of CXCR4 expression in ALL, M(4)+M(5), M(2) patient group were 78.47 +/- 33.96, 67.21 +/- 24.29, 41.66 +/- 17.18, respectively. CXCR4 expression in ALL and M(4)+M(5) patient groups were higher than that in M(2) patient group (P > 0.05). There was no significant difference between the ALL and M(4)+M(5) patient group (P > 0.05). The MFI of CXCR4 expression in patients with extramedullary infiltration and patients without extramedullary infiltration were 81.72 +/- 27.63, 36.94 +/- 11.86 respectively. The former was higher than the latter (P < 0.05). It is concluded that the higher expression of CXCR4 on acute lymphoblatic and monocytic leukemia cells may be one of the molecular mechanisms of extramedullary infiltration in both kinds of leukemia. The average plasma levels of SDF-1alpha decreased in leukemia patients and this decrease not related to the extramedullar infiltration, which may be due to the SDF-1alpha local expression in the organ infiltrated.
Acute Disease ; Adolescent ; Adult ; Chemokine CXCL12 ; Chemokines, CXC ; biosynthesis ; genetics ; Child ; Child, Preschool ; Female ; Humans ; Leukemia ; metabolism ; pathology ; Leukemia, Myeloid, Acute ; metabolism ; pathology ; Leukemic Infiltration ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; metabolism ; pathology ; Receptors, CXCR4 ; biosynthesis ; genetics ; Stromal Cells ; metabolism

The stromal cell-derived factor 1 (SDF-1) interacts with its receptor CXCR4 to transduction signals, playing important roles in most physiological and pathological processes. It is reported that CXCR4 is highly expressed in many kinds of hematological malignancies and closely related to the prognosis, drug resistance and relapse of diseases. The growth of tumor cells can be inhibited by the anti-SDF-1 antibody or anti- CXCR4 antibody, supporting a new way for the therapy against hematological malignancies. Their expression in relation with prognosis and drug resistance of hematological malignancies are summarized in this review.
Chemokine CXCL12 ; biosynthesis ; genetics ; Drug Resistance, Neoplasm ; genetics ; Hematologic Neoplasms ; metabolism ; pathology ; Humans ; Prognosis ; Receptors, CXCR4 ; biosynthesis ; genetics ; Signal Transduction ; Stromal Cells ; metabolism

To investigate the effect of in vivo rhG-CSF on the CXCR-4 expression of hematopoietic progenitor or stem cells in bone marrow and peripheral blood, the expressions of CXCR-4 on CD34(+) cells and mononuclear cells of bone marrow and peripheral blood from healthy donor before and after mobilization were detected by three-color fluorescence analysis. The results showed that a significantly higher expression of CXCR4 on CD34(+) cells of bone marrow and mononuclear cells of peripheral blood, as compared to those before mobilization. There were no significant differences of CXCR-4 expression of CD34(+) cells in peripheral blood after mobilization, as compared with steady state bone marrow, and no dynamic change of mononuclear cells expressing CXCR-4 in bone marrow before and after mobilization. Significant positive correlation were found between the percentage of CD34(+) cells in bone marrow before mobilization and that in bone marrow and peripheral blood after mobilization; furthermore, the percentage of CD34(+) cells of bone marrow before mobilization had a positive correlation with both the count of CD34(+) cells per kilogram on the day of collection in bone marrow and peripheral blood after mobilization. It is concluded that the mobilization of hematopoietic cells may be involved in the signaling of SDF-1/CXCR-4 according to the increase of the surface expression of CXCR-4 on CD34(+) cells in bone marrow and on the MNC in peripheral blood after mobilization; meanwhile, the high surface expression of CXCR-4 may contribute to the MNC engraftment, monitoring the percentage of CD34(+) cells in bone marrow before mobilization can be regarded as a predictive factor for mobilization outcome.
Adolescent ; Adult ; Aged ; Antigens, CD34 ; blood ; Blood Donors ; Bone Marrow Cells ; cytology ; drug effects ; metabolism ; Female ; Flow Cytometry ; methods ; Granulocyte Colony-Stimulating Factor ; administration & dosage ; pharmacology ; Hematopoietic Stem Cell Mobilization ; methods ; Hematopoietic Stem Cell Transplantation ; Hematopoietic Stem Cells ; cytology ; drug effects ; metabolism ; Humans ; Male ; Middle Aged ; Peripheral Blood Stem Cell Transplantation ; Receptors, CXCR4 ; biosynthesis ; blood ; Recombinant Proteins

OBJECTIVETo investigate the coreceptors CCR5 and CXCR4 expressions on the peripheral blood T lymphocytes in HIV/AIDS patients, with an analysis of their clinical value.

METHODSThirty HIV/AIDS patients and 16 normal controls were selected and flow-cytometry was used to detect the coreceptors CCR5 and CXCR4 expressions in whole blood samples taken from the patients and controls. An analysis was made of the correlation of the coreceptor expression with CD4 T cell counts and the activation of CD4+/ CD8+ T cells (HLA-DR+/CD38+).

RESULTSThe CCR5 expression on CD8+ lymphocytes and the CXCR4 expression on the CD4+/ CD8+ T lymphocytes of the HIV/AIDS group were higher than those of the normal controls (P < 0.01). The CCR5 and CXCR4 expressions on the CD4+/CD8+ T lymphocytes of the HIV/AIDS patients was significantly correlated with the activation of CD4+/CD8+ T cells (HLA-DR+/CD38+) (P < 0.05).

CONCLUSIONThe expressions of CCR5 and CXCR4 are significantly correlated with the immune system reaction to HIV and the disease progression in HIV infected patients.

Acquired Immunodeficiency Syndrome ; blood ; Adolescent ; Adult ; Case-Control Studies ; Child ; Child, Preschool ; Female ; HIV Infections ; blood ; Humans ; Male ; Middle Aged ; Receptors, CCR5 ; biosynthesis ; Receptors, CXCR4 ; biosynthesis ; T-Lymphocytes ; metabolism