A novel synthetic hexapeptide (SFKLRY-NH2) that displays angiogenic activity has been identified by positional scanning of a synthetic peptide combinatorial library (PS-SPCL). This study was carried out to investigate the irritation of the SFKLRY-NH2 on the skin. The tests were performed on the basis of Korea Food and Drug Administration (KFDA) guidelines. In results, cell toxicity is not appeared for SFKLRY-NH2 in HaCaT cells and B16F10 cells. SFKLRY-NH2 induced no skin irritation at low concentration (10 microM), mild irritation at high concentration (10mM). We consider that this result is helpful for saying about the safety of SFKLRY-NH2 in clinical use.
Korea ; Oligopeptides ; Peptide Library ; Skin ; United States Food and Drug Administration

We developed a novel method for constructing nearly random peptide library. Genomic DNAs extracted from tissue or cells of large genome species were digested with frequent cutter to produce short DNA fragments. These short fragments can be considered nearly random. Nearly random peptide libraries can be constructed by cloning the short fragments into appropriate expression vectors and transformation into host cells. Genomic DNA from one species can be digested with different restriction enzymes and ligated to different reading frames to produce several different libraries. In this study, we digested tobacco genomic DNA with two enzymes and cloned into three different reading frames to make totally six nearly random peptide libraries.
DNA, Plant ; genetics ; Genome, Plant ; genetics ; Peptide Library ; Tobacco ; genetics

Tumor is a serious threat to human health. At present, surgical resection, chemoradiotherapy, targeted therapy and immunotherapy are the main therapeutic strategies. Monoclonal antibody has gradually become an indispensable drug type in the clinical treatment of cancer due to its high efficiency and low toxicity. Phage antibody library technology (PALT) is a novel monoclonal antibody preparation technique. The recombinant immunoglobulin variable region of heavy chain (VH)/variable region of light chain (VL) gene is integrated into the phage vector, and the antibody is expressed on the phage surface in the form of fusion protein to obtain a diverse antibody library. Through the process of adsorption-elution-amplification, the antibody library can be screened to obtain the antibody molecule with specific binding antigen as well as its gene sequence. PALT has the advantages of short antibody production cycle, strong plasticity of antibody structure, large antibody yield, high diversity and direct production of humanized antibodies. It has been used in screening tumor markers and preparation of antibody drugs for breast cancer, gastric cancer, lung cancer and liver cancer. This article reviews the recent progress and the application of PALT in tumor therapy.
Humans ; Bacteriophages/genetics* ; Immunoglobulin Variable Region/genetics* ; Gene Library ; Antibodies, Monoclonal/therapeutic use* ; Immunotherapy ; Peptide Library

OBJECTIVETo identify and characterize the polypeptides specifically binding to human B type natriuretic peptide (BNP) screened from 12TM phage display peptide library.

METHODSThe BNP-binding peptides were screened from 12TM phage display peptide library and identified by ELISA.

RESULTSAfter 4 rounds of screening, 10 of the 16 phage clones were identified as the positive clones which could bind to BNP. Five amino acid sequences were obtained in the 10 positive clones. Dose-dependent ELISA results demonstrated that the screened polypeptides could specifically bind to BNP.

CONCLUSIONThese screened polypeptides can bind specifically to BNP, which provides a basis for further research on expression and purification of anti-BNP polypeptides and the development of the detection kit of BNP.

Humans ; Natriuretic Peptide, Brain ; metabolism ; Peptide Library ; Peptides ; analysis ; isolation & purification ; metabolism ; Protein Binding

Autoantigens ; blood ; Gene Library ; Hepatitis, Autoimmune ; genetics ; immunology ; Hepatocytes ; immunology ; Humans ; Peptide Library ; Polymerase Chain Reaction ; methods

OBJECTIVESTo construct and screen a primarily phage display library of HCV C and E1 genes evolved with an artificial pattern.

METHODSTwo genes of about 1 kb with different genotypes were evolved by DNA shuffling. The re-assembled HCV C and E1 genes were cloned into a phage vector. After being rescued with helper phage M13KO7, a phage display library was constructed. Then the library was screened with anti-C and E1 McAb. Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) was carried out on twenty individual phage clones selected randomly to detect their binding and reactive activity with high-titer HCV-positive sera. Normal sera were used as controls.

RESULTSThe phage display library of HCV C and E1 genes which evolved with an artificial pattern was constructed. Their capacity amounted to 1.64 x 10(6), and 86 percent of the clones contained C and E1 genes. After four rounds of panning, the phage library was specifically enriched. Twelve positive clones were successfully screened.

CONCLUSIONThe capacity and diversity of the constructed library are enough for screening. The results demonstrate the superiority of the specific binding and reactive activity and affinity of the 12 phage clones from the HCV positive sera.

DNA, Viral ; genetics ; Gene Library ; Hepacivirus ; genetics ; Peptide Library ; Viral Core Proteins ; genetics ; Viral Envelope Proteins ; genetics

The application of in vitro selection method to isolate nucleic acids, peptides and proteins according to their functions has been studied intensively in recent years. In vitro display technologies are not limited by cellular transformation efficiencies; thus, very large libraries of up to 10(13)-10(14) members can be built. The most popular in vitro display technologies are ribosome display and mRNA display; ribosome display achieves the mRNA-ribosome-nascent peptide complexes by stalling the translating ribosome in an in vitro translation reaction. In mRNA display, the mRNA-protein complex is achieved by binding the two macromolecules through a small adaptor molecule, typically puromycin; these mRNA-peptide fusions can then be purified and subjected to in vitro selection. In vitro display technologies provide a different approach to the in vitro selection and directed evolution of peptides and proteins. This review focuses on the principle and method of ribosome display and mRNA display technologies, and discusses their applications.
Animals ; Directed Molecular Evolution ; Gene Library ; Humans ; Peptide Library ; Protein Interaction Mapping ; methods ; RNA, Messenger ; chemistry ; genetics ; Ribosomes ; chemistry ; genetics

Antibodies are immunoglobulins specifically introduced by immunity response of high animals, with the responsibility for recognising and cleaning out specific antigens. Antibody is not only a powerful weapon against pathogen invasion in the organism, but also a tool for specific molecular recognition used in basic scientific research. The diversity of antibody molecules resulted in the concept of antibody library; each individual animal is a natural antibody library. In the post-genome era, in order to fit various "omics", especially for proteomics requirement of high throughput technology, some gene engineering antibody libraries and antibody alternative libraries have been constructed based on phage display technology. Yet, more and more in vitro display systems such as ribosome display, mRNA display have been used for antibody library study, and that present more advantages than phage display. This mini review outlines the genesis, development and application prospect of antibody libraries according to the published reviews and research articles, and offers up to date development and application prospect of antibody library technology.
Animals ; Antibodies ; genetics ; physiology ; Antibody Diversity ; genetics ; Antibody Specificity ; Combinatorial Chemistry Techniques ; Gene Library ; Humans ; Peptide Library

Human cytomegalovirus encodes an unusual protein kinase UL97 which can phosphorylate exogenous substrates, including histone H2B and nucleoside analogs such as ganciclovir. The previous result interestingly showed that the peptides phosphorylated by UL97 have K/R at the 5 positions (P+5) downstream from the pSer. To confirm the importance of the basic residue in the position, we used two peptide libraries, 4S4K (MAXXXXSXXXXKXANNN) and 4S6N (MAXXXXSXXXXXXNNN). The activity of phosphorylation by UL97 was higher in the peptide library 4S4K than 4S6N, suggesting the importance of basic residue at P+5 position. The screening with a peptide library 4S4K showed slight tendencies for N in the P+1 and P+2, M in the P+2, K in the P+4 and P+6 positions and several amino acids in the other positions. This result will give information to develop an optimal peptide for screening a novel UL97 inhibitor.
Amino Acids ; Cytomegalovirus* ; Ganciclovir ; Histones ; Humans* ; Mass Screening* ; Peptide Library* ; Peptides ; Phosphorylation ; Protein Kinases* ; Substrate Specificity*

Cytokines such as erythropoietin (EPO) and thrombopoitein (TPO) and so on, which stimulate hematopoiesis, can regulate self-renewal, proliferation, differentiation, maturation and programmed cell death of hematopoietic cells through specifically binding to surface receptors. Recently random phage display peptide libraries and other screening methods have been used to isolate mimetic including small peptides and non-peptides molecules, which can mimic the same effects as cytokines, such as EPO and TPO, and demonstrate the similar potency and activity as EPO and TPO in a panel of in vitro biological assays and in animal experiments. These approaches are critical to further research of interactive mechanisms between cytokine and receptor, receptor activation and rational design of other desired cytokine mimetic. This review concisely introduced recent advances in research on mimetic of EPO, TPO and other cytokines and future directions.
Animals ; Cytokines ; pharmacology ; Erythropoietin ; pharmacology ; Hematopoiesis ; drug effects ; physiology ; Humans ; Peptide Library ; Peptides ; pharmacology ; Thrombopoietin ; pharmacology