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Display Library (display + library)
Kinds of Display Library Selected AbstractsSpecific Fab fragments recovered by phage display technique recognizing human spermatozoaINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2009Dorota Fiszer Summary Human hybridoma cell lines are often unstable and loose ability for antibody production. Sometimes, they show low and varying levels of heavy and light chains synthesis. Therefore it is reasonable to preserve generated specificities of light and heavy chains by cloning them to phagemid vector and creating phage display library. The aim of this study was to construct phage display library of Fab fragments recognizing sperm surface antigens. The source of mRNA constituted seven hybridoma cell lines producing antisperm antibodies which was proved by ELISA, and agglutination test as well as by inhibition of sperm to penetrate hamster oocytes. Fragments of cDNA encoding ,/, and , chains were cloned into pComb3HSS phagemid vector and amplified in XL-1Blue. The library was panned against whole unfixed sperm cells. Three positive clones selected after fourth round of panning showed heavy chain belonging to VH4 family, two of them (G28, K61) possessed lambda chain from VL2 family and one (H43) kappa chain from VK1 family. As these Fabs revealed similarities to antibodies against some proteins involved in sperm motility and cell fusion it can be suggested that these Fabs may be a cause of infertility. Finally, we proved that it is feasible to preserve specificities produced by human hybridomas using phage display technique and we recovered some Fabs which may be of diagnostic and research value, and may also have some value for contraceptive vaccine. [source] Use of a Phage Display Technique to Identify Potential Osteoblast Binding Sites Within Osteoclast Lacunae,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2002Tzong-Jen Sheu Abstract There is a temporal coupling between the processes of bone resorption and bone formation in normal skeletal remodeling. That is, osteoblastic activity usually follows episodes of osteoclastic activity. However, what has not been universally appreciated is that there also is a spatial coupling between these processes. Bone formation only occurs in the immediate vicinity of the resorptive event. In this study, we describe a phage display technique that has been used to identify the mechanisms by which osteoblasts recognize components of the prior resorbed lacunar surface. Using a type V tartrate-resistant acid phosphatase (TRAP) as the bait and a random peptide M13 phage display library as the probe, we have identified specific sequences that show a very high affinity for TRAP. One of these peptides, designated clone 5, has a subnanomolar Kd for TRAP, interacts with TRAP in a Far-Western assay, binds exclusively to TRAP within osteoclast lacunae, is present in osteoblasts, and can effectively block osteoblast binding to resorption surfaces. The clone 5 peptide shows a high homology to glypican 4 (GPC4), a proteoglycan attachment receptor found in a number of cell types. [source] Phage display screening for peptidic chitinase inhibitors,JOURNAL OF MOLECULAR RECOGNITION, Issue 6 2008Cordula Petter Abstract A phage display library with disulfide-cyclized peptides was screened for peptides binding to chitinases from Serratia marcescens. One of those peptides was found to efficiently inhibit chitinase A and two others were inhibitors of chitinase B. Complete substitutional analysis of all three peptides using cellulose-bound peptide spot synthesis revealed key interaction positions and allowed optimization of the chitinase B inhibitory peptides towards higher affinity, with inhibitory constants in the lower nanomolar range. Inhibition by all peptides proved to be competitive and highly specific for the chitinase used to select them, as shown with a series of chitinases from different organisms. Copyright © 2008 John Wiley & Sons, Ltd. [source] Single-chain variable fragment antibodies against the neural adhesion molecule CHL1 (close homolog of L1) enhance neurite outgrowthJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2002Ling Dong Abstract The neural cell adhesion molecule CHL1 (close homolog of L1) plays important roles in neurite outgrowth and neuronal survival in vitro. Reproducible and functionally active CHL1 antibodies are critical for a better understanding of the functional properties of CHL1 in vitro and in vivo. We have isolated human single-chain variable fragment (scFv) antibodies against mouse CHL1 from a human synthetic phage display library. To improve the binding activity of such antibodies, a clone (C12) was selected for affinity maturation by combined random mutagenesis of the VH gene and site-directed cassette mutagenesis to introduce random mutations in the complementarity determining region 3 (CDR3) of the VL gene. From the mutant phage display library, we selected a clone (6C2) that gave the strongest signal as determined by ELISA. The dissociation constant of 6C2 (Kd 2.28 × 10,8 M) was increased approximately 85-fold compared with the wild-type clone C12 (Kd 1.93 × 10,6 M). 6C2 detected CHL1 by Western blot analysis in mouse brain homogenates and detected CHL1 in CHL1-transfected cells by immunofluorescence. Furthermore, the wild-type and affinity-matured antibodies promoted neurite outgrowth of hippocampal and cerebellar neurons in vitro. Our results suggest that the affinity-matured CHL1 scFv antibody will serve a range of applications in vitro and in vivo. © 2002 Wiley-Liss, Inc. [source] Function-modulating human monoclonal antibodies against platelet-membrane receptors isolated from a phage-display libraryJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2003Y. Hagay Summary., Monoclonal antibodies to platelet membrane receptors have been used extensively for analysis of receptor structure and function. Function-blocking human antibodies are being used for the development of antiplatelet drugs. We isolated human monoclonal antibodies from a library of single-chain Fv (scFv) antibodies displayed on the surface of filamentous phage, by selection on whole platelets. Eight different platelet-binding clones were isolated, of which three bound to the platelet-membrane glycoprotein (GP) GPIb in an ELISA assay. Specific elution with a recombinant polypeptide of von Willebrand factor (VWF) spanning the GPIb, binding site, yielded the same three phage clones. Two of the three anti-GPIb clones could be purified as scFv monoclonal antibodies, and they competed with each other for binding to intact platelets, suggesting that they bind at or near the same site on GPIb. Their binding affinities differed, however, and the clone with higher affinity inhibited ristocetin-induced platelet aggregation. These data indicate that selection from a phage display library of human scFvs using whole platelets can be applied for the isolation of functional antiplatelet-GPIb antibodies useful for the development of new therapeutic and diagnostic strategies. [source] Identification of oligopeptides binding to peritoneal tumors of gastric cancerCANCER SCIENCE, Issue 10 2006Noriyuki Akita This is a report of in vivo intraperitoneal biopanning, and we successfully identified a novel peptide to target the multiple peritoneal tumors of gastric cancer. A phage display library was injected directly into the abdominal cavity of mice bearing peritoneal tumors of human gastric cancer, and phages associated with the tumors were subsequently reclaimed from isolated samples. The tumor-associated phages were amplified and the biopanning cycle was repeated five times to enrich for high affinity tumor-selective binding peptides. Finally, a tri-peptide motif, KLP, which showed homology with laminin 5 (a ligand for ,3,1 integrin), was identified as a binding peptide for peritoneal tumors of gastric cancer. Phage clones displaying the sequence KLP showed 64-fold higher binding to peritoneal tumors than control phage and were preferentially distributed in tumors rather than in normal organs after intraperitoneal injection into mice. In addition, the KLP phages were more likely to bind to cancer cells in malignant ascites derived from a patient with recurrent gastric cancer. Synthesized peptide containing the motif KLP (SWKLPPS) also showed a strong binding activity to peritoneal tumors without cancer growth effect. Liposomes conjugated with SWKLPPS peptide appeared significantly more often in tumors than control liposomes after intraperitoneal injection into mice. Furthermore, modification of liposomes with SWKLPPS peptide enhanced the antitumor activity of adriamycin on gastric cancer cells. The peptide motif KLP seems a potential targeting ligand for the treatment of peritoneal metastasis of gastric cancer. (Cancer Sci 2006; 97: 1075,1081) [source] Efficient generation of respiratory syncytial virus (RSV)-neutralizing human MoAbs via human peripheral blood lymphocyte (hu-PBL)-SCID mice and scFv phage display librariesCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 1 2000H. Nguyen RSV is one of the major causes of pneumonia and bronchiolitis in infants and young children and is associated with high mortality. RSV neutralizing human antibody (hu-Ab) is known to mediate resistance to viral infection as well as to be an effective treatment for severe lower respiratory tract RSV infection. We have previously demonstrated that human primary and secondary immune responses can be established in severe combined immunodeficient mice engrafted with human peripheral blood lymphocytes (hu-PBL-SCID). By combining this animal model with the single-chain Fv antibody (scFv) phage display library technique, we were able to investigate further its clinical potential by generating a panel of human scFvs that exhibit both high F glycoprotein (RSV-F) binding affinities (,108 M,1) and strong neutralizing activities against RSV infection in vitro. Sequencing analysis of the randomly isolated anti-RSV-F scFv clones revealed that they were derived from different VH families with mutations in the complementarity-determining region 1 (CDR1). The results suggest that: (i) RSV-F-specific human immune responses and affinity maturation can be induced in hu-PBL-SCID mice; and (ii) this approach can be applied to generate large numbers of human scFvs with therapeutic potential. Despite the fact that hu-PBL-SCID mouse and human scFv phage display library have individually been established, our approach contributes a simple and significant step toward the generalization of antigen-specific human monoclonal antibody (hu-MoAb) production and their clinical applications. [source] | ||||||||||