Human transferrin receptor (TfR) was isolated from homogenates of placental tissues by affinity chromatography on transferrin-Sepharose, and then used to screen human scFv against it from a fully-synthesized phage scFv library. After verifying the specificity, gene fragment of one of the selected scFv was inserted into the plasmid pET22b(+) and transformed into E. coli BL21(DE3) . Expression of scFv in transformant was induced with 0.5mmol/L IPTG. ELISA assay on HeLa cells showed that scFv protein could recognize and bind to TfR on the surface of HeLa cells. The scFv was purified by one-step affinity chromatography with Ni+ -NTA agarose, and injected into Kunming mouse via tail veins. This scFv was detected in brain tissues 1h later by capillary depletion method, which indicates that scFv protein can permeate through the blood brain barrier by mediation of the TfR receptor. Our works lay the foundation for the treatment of tumors and central nervous system diseases.
Animals ; Antibodies, Anti-Idiotypic ; genetics ; isolation & purification ; metabolism ; Escherichia coli ; genetics ; metabolism ; HeLa Cells ; Humans ; Immunoglobulin Fragments ; biosynthesis ; genetics ; immunology ; Immunoglobulin Variable Region ; biosynthesis ; genetics ; immunology ; Mice ; Receptors, Transferrin ; genetics ; immunology ; Recombinant Proteins ; biosynthesis ; genetics ; Transferrin ; metabolism

Extracellular Signal-Regulated MAP Kinases ; metabolism ; Glomerular Mesangium ; immunology ; Glycosylation ; Humans ; Immunoglobulin A ; metabolism ; Phosphorylation ; Receptors, Fc ; analysis ; genetics ; Receptors, Transferrin ; analysis ; genetics

To study the effect of interleukin-15 (IL-15) on the proliferation, differentiation and apoptosis of MDS CD34(+) cells, CD34(+) cells of high enrichment were separated by MACS system, and cultured in liquid media with different concentration of IL-15 in treated group and without IL-15 in the control group. Apoptosis of hematopoietic precursors was assayed by propidium iodine staining and cell by FCM, and the other MDS CD34(+) cells were stained by cytochemical staining after culture. The results showed that after culture with IL-15 the proliferation and differentiation of MDS CD34(+) cells were obviously promoted. It was found the every lineage of mature cells developed, the expressions of cell surface antigens CD71, CD33 and CD19 all increased in the MDS CD34(+) cell treated with IL-15. It is suggested that IL-15 stimulates the proliferation and differentiation of MDS CD34(+) cells, and partly shows anti-apoptosis effects which may be applicable to the therapy MDS.
Antigens, CD ; immunology ; Antigens, CD19 ; immunology ; Antigens, CD34 ; immunology ; Antigens, Differentiation, Myelomonocytic ; immunology ; Apoptosis ; drug effects ; Bone Marrow Cells ; drug effects ; immunology ; pathology ; Cell Cycle ; drug effects ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Flow Cytometry ; Humans ; Interleukin-15 ; pharmacology ; Microscopy, Fluorescence ; Myelodysplastic Syndromes ; blood ; immunology ; pathology ; Receptors, Transferrin ; immunology ; Sialic Acid Binding Ig-like Lectin 3

OBJECTIVES: Immunologic studies have characterized the numbers and types of inflammatory cells in diseased inflammatory bowel disease (IBD) mucosa but have yielded conflicting results regarding intestinal lymphocytes activation in IBD. We investigated the levels of lymphocytes subsets, interleukin-2 receptor, transferrin receptor, and T cell receptors in mainly isolated lamina propria lymphocytes. Including intraepithelial lymphocytes of normal colonic mucosa or IBD (ulcerative colitis and Crohn's disease) mucosa to understand the pathogenesis of IBD. We have results from this study. RESULTS: 1) In comparing ulcerative colitis with control, IL-2R (p < 0.05), TR (p < 0.01), and CD3/HLA-DR (<0.05) showed a significant increase. 2) In comparing Crohn's disease with control, CD3 (P < 0.05), TCR alpha/beta (p < 0.01) and TCR gamma/delta (p < 0.05) showed a significant decrease. 3) In comparing Crohn's disease with ulcerative colitis, CD19 (p < 0.01), TR (p < 0.01), TCR alpha/beta (p < 0.01) and TCR gamma/delta (p < 0.05) showed a significant decrease. CONCLUSION: From these results, there are increased T cell markers, IL-2R, TR, and CD3/HLA-DR in UC, but differently, decreased CD3, TCR alpha/beta and TCR gamma/delta in CD compared with control. In addition, definitive differences in lymphocytes markers, CD19, TR, TCR alpha/beta and TCR gamma/delta, which are higher in UC than in CD, may elucidate the different immunopathogenesis between UC and CD.
Adult ; Antigens, CD3/analysis ; Colitis, Ulcerative/pathology ; Colitis, Ulcerative/immunology ; Colitis, Ulcerative/diagnosis* ; Comparative Study ; Crohn Disease/pathology ; Crohn Disease/immunology ; Crohn Disease/diagnosis* ; Diagnosis, Differential ; Female ; HLA-DR Antigens/analysis ; Human ; Immunophenotyping* ; Intestinal Mucosa/pathology ; Intestinal Mucosa/immunology* ; Male ; Middle Age ; Receptors, Antigen, T-Cell/analysis ; Receptors, Interleukin-2/analysis ; Receptors, Transferrin/analysis ; Sensitivity and Specificity ; Tissue Culture

This study was aimed to investigate the changes of CD34(+) and CD71(+)CD45(-) cell levels in MDS and AA patients. A total of 25 cases MDS and 43 cases of AA (18 cases SAA and 25 cases of NSAA) from January 2010 to October 2013 in the Department of Hematology, affiliated hospital of Hebei United University were enrolled in this study. The complete blood count, bone marrow smears, bone marrow biopsy, karyotype analysis and bone marrow blood cell immune genotyping (mainly the proportion of CD34(+) cells, CD71(+)CD45(-) cells in nucleated cells) were carried out for all patients; the changes of CD34(+) and CD71(+)CD45(-) cell levels in patients with MDS and AA (SAA NSAA) were compared; the differences of white blood cell count, platelet count and hemoglobin concentration in patients with count of CD71(+)CD45(-) ≥ 15% or <15% were analyzed. The results showed that the count of CD34(+) in MDS group was higher than that in AA (NSAA and SAA) group (P < 0.05). The count of CD71(+)CD45(-) cells in MDS group was higher than that in SAA (P < 0.05), there was no significant difference between NSAA group and MDS group. In MDS group with CD71(+)CD45(-) ≥ 15%, the platelet count was significantly higher than that in NSAA group (P < 0.05); and there was no statistical difference for leukocyte, platelet count and hemoglobin level between MDS and NSAA group with CD71(+)CD45(-) <15% (P > 0.05). It is concluded that the count of CD34(+) cells in MDS patients is significantly higher than that in AA and SAA patients. The count of CD71(+)CD45(-) cells in MDS group is significantly higher than that of SAA group. The platelet count in MDS patients with CD71(+)CD45(-) cells ≥ 15% is significantly higher than that of the NSAA group.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anemia, Aplastic ; pathology ; Antigens, CD ; immunology ; Antigens, CD34 ; immunology ; Blood Cell Count ; Bone Marrow ; Bone Marrow Cells ; cytology ; immunology ; Female ; Flow Cytometry ; Humans ; Leukocyte Common Antigens ; immunology ; Male ; Middle Aged ; Myelodysplastic Syndromes ; pathology ; Receptors, Transferrin ; immunology ; Young Adult

To obtain single chain variable fragment (scFv) and bivalent single chain variable fragment (bsFv) against transferrin receptor, up-stream and down-stream primers were designed according to the complementary sequences of FR1 region of variable heavy (VH) and FR4 of variable light (VL), respectively, which contained inter-linker G4S and the restriction endonuclease SfiI, AscI and NotI. Two pieces of scFv fragments were first amplified through PCR and then inserted into plasmid pAB1, which could express scFv protein once induced by IPTG in the host bacteria. To express scFv and bsFv, E. coli TG1 was cultured in LB broth and was induced by IPTG. The restriction enzyme digestion map and DNA sequencing demonstrated that scFv and bsFv genes were successfully inserted into the expression plasmid. SDS-PAGE and Western blotting revealed the protein band at 35kD and 60kD, which were consistent with the molecular weight of scFv and bsFv respectively. Flow cytometry showed that scFv and bsFv harbored the specific binding activity with TfR expressed in various tumor cells, and the avidity of bsFv was higher than that of the parent scFv.
Base Sequence ; Cloning, Molecular ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Genetic Vectors/genetics ; Hep G2 Cells ; K562 Cells ; Molecular Sequence Data ; Receptors, Transferrin/*immunology ; Recombinant Fusion Proteins/biosynthesis ; Recombinant Fusion Proteins/genetics ; Single-Chain Antibodies/*biosynthesis ; Single-Chain Antibodies/genetics

The single-chain antibody gene (ox26-scFv) to transferrin receptor (TfR) was synthesized and amplified by three-step PCR. After sequencing, the gene was cloned into prokaryotic expression vector pTIG-Trx which carried thioredoxin (Trx) gene and a C-terminal His.tag. The Ox26-scFv proteins achieved 31% yields of total bacteria proteins at 20 degrees C, after 0.02mM IPTG induction using the strain E. coli BL21 (DE3). The soluble scFv proteins in cytoplasm suspension were about 35% and the inclusion bodies were about 65%. The soluble products were purified by immobilized metal chelation affinity chromatography (Ni-NTA), a single band with molecular weight 29 kD appeared on SDS-PAGE gel. Rat GH3 cell immunocytochemistry staining showed that Ox26-scFv protein could recognize and bind to transferrin receptor. Injected SD rats with Ox26-scFv proteins by tail veins, the antibodies were detected from brain tissues specially on the brain capillaries 4 h later which indicate that Ox26-scFv proteins have a good target function to brain capillaries and can permeate the blood-brain barrier mediated by the transferrin receptors.
Animals ; Antibodies ; administration & dosage ; genetics ; metabolism ; Antibody Formation ; Base Sequence ; Blood-Brain Barrier ; drug effects ; Drug Delivery Systems ; Genetic Vectors ; Molecular Sequence Data ; Rats ; Rats, Sprague-Dawley ; Receptors, Transferrin ; immunology

OBJECTIVETo construct the localization system involving anti-TfR monoclonal antibody (McAb) and AFP promoters and assess its effect on human hepatoma cell lines.

METHODSThe conjugate of anti-TfR McAb and polylysine (PLL) was made by SPDP and purified by molecular screen chromatography. DNA blocking test determined that the ratio of one pEBAF/tk to six Ab-PLL was the most suitable to couple them. The pEBAF/tk recombinant plasmid bearing HSV-TK gene was coupled to Ab-PLL by noncovalent bond. The pEBAF/tk was transferred into human hepatoma cell line HepG2, SMMC7721 and pulmonary cancer cell line A549 by receptor-mediated gene delivery (Ab-PLL-DNA) and liposome procedure. The growth inhibitory rates of HepG2, SMMC7721 and A549 cells were measured by MTT assay.

RESULTSThe inhibitory rates of HepG2/tk in 100 mg/L and 1 mg/L of GCV were 60.5% and 24.3%, respectively. The inhibitory rate of GCV to SMMC7721 was 23.2% in 3 days. The pulmonary cancer cell A549, A549/tk (Ab) and A549 /tk (lipo) could not be inhibited by the addition of GCV.

CONCLUSIONThe localization system employed in this paper has high specificity, effectiveness and safety for gene therapy. It would be a promising strategy for gene therapy.

Antibodies, Monoclonal ; therapeutic use ; Carcinoma, Hepatocellular ; therapy ; Cell Line, Tumor ; Ganciclovir ; therapeutic use ; Genetic Therapy ; Humans ; Liver Neoplasms ; therapy ; Receptors, Transferrin ; immunology ; Simplexvirus ; enzymology ; Thymidine Kinase ; genetics ; alpha-Fetoproteins ; genetics

OBJECTIVETo evaluate the value of serum soluble transferrin receptor (sTfR) concentration in predicting early response to immunosuppressive therapy (IST) in severe aplastic anemia (SAA).

METHODSClinical data and hematologic responses of 140 SAA patients treated with rabbit antithymocyte globulin (rATG) combination with cyclosporine in our hospital were retrospectively analyzed. Correlation of pre-IST baseline of sTfR and IST responses was statistically analyzed and receiver operating characteristic (ROC) curve was used to estimate the sensitivity and specificity of sTfR in prediction of early responses.

RESULTSSerum concentration of sTfR in very SAA (VSAA) patients were significantly lower than SAA and transfusion dependent non-SAA cases (P=0.001). The responders, especially at 3 months, had significantly higher pre- IST baseline of sTfR [median, 0.89 (range, 0.21-2.42) mg/L] than that [median, 0.58 (range, 0.13-1.88) mg/L] of non-responders (P=0.005). The cutoff level of 0.91 mg/L and 0.88 mg/L for predicting responses at 3 and 6 months were established based on the ROC curve, with the degree of accuracy of 65.0% and 60.7% respectively. Multivariate analysis showed that pre-IST baseline of sTfR was the independent factor of predicting response at 3 months (P=0.007) and at 6 months (P=0.021).

CONCLUSIONAs a indicator of bone marrow failure severity, sTfR could predict early response to IST therapy in aplastic anemia.

Adolescent ; Adult ; Aged ; Anemia, Aplastic ; therapy ; Antilymphocyte Serum ; therapeutic use ; Child ; Child, Preschool ; Cyclosporine ; therapeutic use ; Female ; Humans ; Immunosuppression ; Male ; Middle Aged ; Receptors, Transferrin ; immunology ; therapeutic use ; Retrospective Studies ; Sensitivity and Specificity ; Treatment Outcome ; Young Adult

Cord blood represents a large source of hematopoietic stem/progenitor cells. It can be induced to proliferate directly into erythroid progenitors in a appropriate ex vivo culture condition, then to generate mature red blood cells after injection into the body. The combination of Flt3 ligand, TPO, SCF and EPO is ideal for cord blood MNC to proliferate into erythroid progenitors. This study was aimed to evaluate the effect of FL, SCF and TPO on CD34(+) expansion. and to investigate influence of the cytokine combination on the proliferation of the CD34(+) cells. Mononuclear cells (MNC) were cultured in serum-free liquid culture system. Experiments were divided into 3 groups. In the group A as control no cytokines were added in the culture system; in the group B the cells cultured with SCF + FL + TPO + EPO + IGF-1; in the group C the cells were cultured with SCF + FL + TPO. EPO and IGF-1 were added at day 6. Part of the renewed MNCs and colony-forming units were counted, the proportion of CD34(+), CD34(+) CD71(+), CD71(+) GPA(+) cells was detected by FACS. The result showed that after 10 days, the the total cord blood cells increased 6.89-folds in group B and 3.06-folds in group C (P < 0.05). The CD34(+) cells increased 4.83-folds in group B and 2.47-folds in group C (P < 0.05). The colony-forming cells (CFCs) increased 4.3-folds in group B and 2.5-folds in group C (P < 0.05). Erythroid progenitors (BFU-E) and CFU-E increased 5.4-folds in group B and 3.1-folds in group C (P < 0.05). The CD34(+)CD71(+) cells increased 8.72-folds in group B and 3.37-folds in group C (P < 0.05). The CD71(+) GPA(+) cells increased 53.4-folds in group B and 30.29-folds in group C. They were different at any time point (P < 0.05). It is concluded that in the group with FL + SCF + TPO, CD34(+) cells and CFC can greatly be expanded from cord blood MNC in the serum-free culture system. In the group with FL + SCF + TPO + EPO + IGF-1, erythroid progenitors can greatly be expanded in the serum-free culture system, supplying EPO at day 0 was better than supplying at day 6. Since the largest number of colony-forming cells such as BFU-E and CFU-E were gained in the TPO + SCF + FL + EPO + IGF-1 group at day 10, the harvest time after cultivation in vitro should be selected at day 10.
Antigens, CD ; blood ; Antigens, CD34 ; blood ; Cell Proliferation ; drug effects ; Cells, Cultured ; Erythroid Cells ; cytology ; immunology ; Fetal Blood ; cytology ; immunology ; Flow Cytometry ; Hematopoietic Stem Cells ; cytology ; immunology ; Humans ; Insulin-Like Growth Factor I ; pharmacology ; Leukocytes, Mononuclear ; cytology ; immunology ; Receptors, Transferrin ; blood ; Stem Cell Factor ; pharmacology ; Thrombopoietin ; pharmacology ; Time Factors