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Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of aggressive lymphoma. The relapsed/refractory DLBCL patients have poor outcomes and DLBCL is still lack of effective treatment standard regimens. How to effectively treat relapsed/refractory DLBCL patients has become a research hotspot, and the current treatment methods include bispecific antibody therapy, chimeric antigen receptor T-cell (CAR-T) therapy, antibody-drug conjugates (ADC) therapy. This paper reviews the progress of targeted drugs/cell treatment for DLBCL at the 64th American Society of Hematology annual meeting.
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Genetic engineering has made sizeable contributions to technical innovation, agriculture, and the development of pharmaceuticals. Various approaches were evolved to control the genetic cloth of cells using both viral and nonviral vector architectures. Gene therapy aims to reverse pathological traits with the aid of the use of viral and nonviral gene shipping mechanisms. Gene transfer motors have made massive strides in becoming more environmentally pleasant, much less risky, and nonimmunogenic, as well as making an allowance for lengthy-time period transgene expression. One of the most tough components of correctly enforcing gene healing treatments in the clinical putting is adjusting gene expression extremely tightly and constantly as and while it's required. This research work will cognizance on using viral vectors for gene concentrated on biological applications with various gene expressions. Due to improvements in viral vector engineering and superior gene regulatory systems to permit and adjust tightly therapeutic gene expression, the technology for using genes to offer a preferred treatment has confirmed to be an effective approach
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Objective:To investigate the effects of miRNA-26a (miR-26a) on the target gene HMGA2 on the proliferation and migration of hepatoma cells and the underlying mechanism. Methods:Liver cancer tissue samples ( n = 30) and adjacent normal tissue samples ( n = 30) pathologically confirmed by Wenzhou Hospital of Traditional Chinese Medicine between September 2018 and September 2019 were collected. MiR-26a mimics, control mimics (miR-Control), high-mobility group A2 protein (HMGA2) siRNA or negative control siRNA (Control) were transfected into human hepatoma cell lines HepG2 or Huh-7 cells. The expression of miR-26a in hepatocellular carcinoma tissue was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). MTT assay and scratch test were performed to determine the ability of cell proliferation and migration. RT-qPCR and western blotting were performed to detect miR-26a and HMGA2 mRNA expression. The relationship between miR-26a and HMGA2 mRNA was analyzed using Bioinformatics and luciferase reporter gene assay. Results:RT-qPCR results showed that the expression level of miR-26a in hepatocellular carcinoma tissue was 0.11 ± 0.02, which was significantly lower than that in normal tissues (0.25 ± 0.03, t = 21.268, P < 0.05). The expression level of miR-26a in stage III + IV was 0.05 ± 0.01, which was significantly lower than that in stage I + II (0.09 ± 0.01, t = 15.491, P < 0.05). Cell experiment showed that in the miR-26a group, the proliferation ability of Huh-7 cells was (3.10 ± 0.30) and (4.10 ± 0.40), and the proliferation ability of HepG2 cells was (3.08 ± 0.31) and (4.11 ± 0.40), which was significantly lower than that in the control group [(3.90 ± 0.40), (5.50 ± 0.60), (3.92 ± 0.41), (5.49 ± 0.58), t = 8.764, 10.634, 11.148, 10.728, all P < 0.05]. In the miR-26a group, the migration ability was (0.50 ± 0.06), (0.65 ± 0.07), which was significantly lower than that in the control group [(1.00 ± 0.10), (0.96 ± 0.10), t = 23.483, 13.910, both P < 0.05]. Bioinformatics and in vitro experiments showed that HMGA2 was a direct target of miR-26a. Restoring the expression of HMGA2 in miR-26a mimics-transfected cells, compared with that in the miR-26a group [(0.24 ± 0.02), (0.31 ± 0.03);(0.45 ± 0.05)], could significantly reverse the inhibitory effect of miR-26a on tumor cell proliferation and migration [(0.31 ± 0.03), (0.40 ± 0.04);(0.93 ± 0.08), t = 10.634, 9.859, 27.868, all P < 0.05). Conclusion:miR-26a inhibits the proliferation and migration of hepatoma cells by directly targeting HMGA2. The abnormal decrease of miR-26a and the increase of HMGA2 may be the important factors that participate in the occurrence and development of liver cancer.
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Objective To establish a conditional knockout mouse model of transcription factor carbohydrate response element-binding protein (ChREBP), so as to provide a technical approach for exploring the biological function of ChREBP in vivo. Methods and results Using Cre/loxP gene targeting strategy, we constructed the gene targeting vector and franked the 8th exon of ChREBP gene with loxP site in embryonic stem cells (ES cells) via homologous recombination. We microinjected the recombined ES clones into blastocysts and implanted into the uterus of pseudopregnant mice to obtain the chimeric mice and ChREBPflox/+ mice. By crossbreeding ChREBPflox/+ mice with Alb-Cre mice, we generated liver-specific ChREBP knockout mice. Conclusion The generation of ChREBP conditional knockout mouse model provides an important means to reveal the physiological function and pathological significance of ChREBP in different tissues.
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The establishment and development of gene knockout mice have provided powerful support for the study of gene function and the treatment of human diseases. Gene targeting and gene trap are two techniques for generating gene knockout mice from embryonic stem cells. Gene targeting replaces endogenous knockout gene by homologous recombination. There are two ways to knock out target genes: promoter trap and polyA trap. In recent years, many new gene knockout techniques have been developed, including Cre/loxP system, CRISP/Cas9 system, latest ZFN technology and TALEN technology. This article focuses on the several new knockout mouse techniques.
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Animals , Humans , Mice , Disease Models, Animal , Embryonic Stem Cells , Gene Knockout Techniques , Gene Targeting , Homologous Recombination , Mice, KnockoutABSTRACT
Objective:To explore the effect of intervention of E-cadherin (E-cad) and B-lymphoma Moloney murine leukemia virus insertion region-1 (Bmi-1) mediated by transcription activator-like effector nuclease (TALEN) on the biological behaviors ofnasopharyngeal carcinoma cells.Methods:Multi-locus gene targeting vectors pUC-DS1-CMV-E-cad-2A-Neo-DS2 and pUC-DS1-Bmi-1 shRNA-Zeo-DS2 were constructed,and the E-cad and Bmi-1 targeting vectors were transferred with TALEN plasmids to CNE-2 cells individually or simultaneously.The integration of target genes were detected by PCR,the expressions of E-cad and Bmi-1 were detected by Western blot.The changes of cell proliferation were detected by cell counting kit-8 (CCK-8) assay.T-he cell cycle and apoptosis were detected by flow cytometry.The cell migration and invasion were detected by Transwell assay.Results:The E-cad and Bmi-1 shRNA expression elements were successfully integrated into the genome of CNE-2 cells,the protein expression level of E-cad was up-regulated,and the protein expression level of Bmi-1 was down-regulated.The intervention of E-cad and Bmi-1 didn't affect the proliferation,cell cycle and apoptosis of CNE-2 cells,but it significantly inhibited the migration and invasion ability of CNE-2 cells.Furthermore,the intervention of E-cad and Bmi-1 together significantly inhibited the migration ability of nasopharyngeal carcinoma cells compared with the intervention of E-cad or Bmi-1 alone (all P＜0.01).Conclusion:The joint intervention of E-cad and Bmi-1 mediated by TALEN can effectively inhibit the migration and invasion of nasopharyngeal carcinoma cells in vitro,which may lay the preliminary experimental basis for gene therapy of human cancer.
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In the past 4 years, CRISPR/Cas9-mediated genome editing becomes the revolutionary tool in life sciences. This tool enables us to edit plant genes with unprecedented throughput, scalability, speed and low cost. In addition to targeted knock-in and knock-out applications, CRISPR/Cas9 also provides an efficient platform for targeted gene activation and suppression. At the same time, accuracy, capacity and efficiency of CRISPR/Cas9 genome editing have been improved for sophisticated genetic manipulation. Furthermore, the genome editing toolbox is expanded by new technologies like CRISPR/Cpf1-mediated genome editing and single base editing. Owing to these recent progresses, CRISPR technology is close to the dream tool for plant sciences and will accelerate the crop genetic improvement through precise genome editing.
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The established immunodeficient animal models could be used as valuable resource for mechanism re-search of related disease in humans, drug discovery and development, translational research and stem cell research.How-ever, it is difficult and low-efficient to establish the genetic modified animal models using traditional technologies.The re-ports for immunodeficient animal models are few in middle-size and large animals.Recently, several effective gene-targeting tools, including ZFNs, TALENs, CRISPR/Cas9, develop quickly and provide technology basis for the establishment of im-munodeficient animal models.In this paper, the technology principles and research progresses of ZFNs, TALENs, CRISPR/Cas9 are introduced.The significant progresses of these emerging technologies achieved in immunodeficient ani-mal models are also elaborated, including KO Rag1/Rag2 rabbit, KO Rag1/Rag2 pig, KO IL2rg pig, KO Ppar-g/Rag1 monkey, and so on.In addition to being models for researching SCID-related diseases in humans, and evaluating the effica-cy and safety of stem-cell engraftment, these models may be also useful to develop surgical procedures for placement of grafts before clinical trials in humans, to produce humanized animals and bridge the gap between laboratory animal and medicical research.The immunodeficient animal models described here represent a step toward the comprehensive evalua-tion of preclinical cellular regenerative strategies.
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Zinc finger protein ZBTB20 is a novel member of the ZBTB zinc finger protein family and shares closest homology with BCL-6 and PLZF. Recent studies on genetically modified mice and patient cohort have revealed that ZBTB20 plays indispensable roles in multiple organs and systems, including the nervous system, liver, pancreatic islets, and immune system. ZBTB20 is an essential regulatory factor in a variety of physiological processes, such as ontogenesis, pain sensation, learning and memory, as well as glucose and lipid metabolism. Meanwhile, recent researches have also showed a close relationship between the abnormality or dysfunction of ZBTB20 and pathophysiological procedures of diseases, such as maldevelopment, mental retardation, tumors and metabolic disorders. As a key repressor governing AFP gene transcription, ZBTB20 exerts a great influence on the gene inactivation of liver AFP after birth and is closely related to the prognosis of hepatocellular carcinogenesis. In humans, the deletion of ZBTB20 is detected in diverse tumors and its point mutation leads to Primrose syndrome. This review summarizes the current knowledge concerning the biological functions of ZBTB20.
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Objective To construct a knock-in targeting vector for expressing of Cre recombinase specifically in islet β cell and provide the key material for knock-in mice with Crr recombinase expressed in islet β cells, providing a knock-out animal model for studying the function of islet β cells. Methods In our study, we constructed a knock-in targeting vector using the third exon of insulin 2 (Ins2) as a target site with λ phage Red recombination system. Through a first homologous recombination, we cloned an about 12 kb genomic DNA fragment from the bacterial artificial chromosome (BAC) which contained Ins2 genomic DNA into a low copy vector pBR322-2s through gap repair. Meantime, a mini-targeting vector containing internal ribosome entry site (.IRES), DNA sequences encoding Crr recombinase and positive-negative-selection (PNS) gene was generated. After second recombination, the final Ins2-Cre targeting vector was generated. Results With the third exon of Ins2 used as the target, we successfully constructed the knock-in targeting vector expressing Cre recombinase which was controlled by endogenous Ins2 gene. Conclusion We have successfully constructed the knock-in targeting vector expressing Cre recombinase, it will provide an important material forcreating animal model of Cre recombinase which is specially expressed in islet β cells.
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Objective To evaluate the inhibitory effects of shRNAs targeting genes encoding viral capsomeres VP1-VP4 on enterovirus 71 (EV71) replication when used alone or in combination.Methods Short hairpin RNAs (shRNAs) targeting genes encoding VP1-VP4 protein of EV71 were designed and then respectively inserted into lentiviral vector pLKD-CMV-GFP-U6 to construct the recombinant plasmids.The expression plasmids together with psPAX2 and pMD2.G were transfected into 293T cells to induce the expression of recombinant lentiviruses,which were collected on the third day after transfection.The titers of recombined lentiviruses were determined by real-time PCR.The effects of shRNAs used alone or in combination on the expression of EV71 at mRNA and protein levels were respectively detected by real-time PCR and Western blot.Results The inhibitory effects of shRNAs on EV71 replication showed no significant differences among various strains (isolated from fatal cases,severe cases,mild cases and FY0805) (P＞0.05).Their inhibition rates were 51.6％ (sh-VP1-1),85.1％ (sh-VP1-2),76.4％ (sh-VP1-3),57.5％ (sh-VP2-1),81.4％ (sh-VP2-2),79.5％ (sh-VP2-3),68.9％ (sh-VP3) and 56.7％ (sh-VP4) respectively,and they were in a dosage dependent manner.sh-VP1-2 in combination with sh-VP2-2 showed the highest inhibition rate reaching up to 96.6％.Moreover,shRNAs used in combination showed better effects than any one used alone even at double dosage.Conclusion All shRNAs targeting viral capsid VP1-VP4 genes showed inhibitory effects on EV71 replication with inhibition rates over 50％ and the effects could be strengthened when using shRNAs in combination.
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Objective To generate Rtn4-A/B knockout mouse model and to explore the biological function of the Rtn4-B gene. Methods The targeting construct for inactivating Rtn4-A/B gene was prepared by bacterial artificial chromosome (BAC). The vector was linearized and electroporated into 129SvEv mouse embryonic stem cells (ES cells). Then the Rtn4-A./B knockout ES cells weremicroinjected into blastula of C57BL/6J mice after superovulation. F1 hybrid mice were bred to obtain mouse aggregation chimeras, and were identifiedby PCR amplification of tail genomic DNA. Results Fourteen clones of gene-targeted ES cells were identified after gene knockout and five male chimeras with a higher than 50 chimeric ratio were produced after microinjection into the blastula. Finally four Rn4-A/B hybrid mice were obtained. Conclusion A Rtn4-A/B deficient mouse strainhas been successfully generated by homologous recombination using genetically modified ES cells.
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La forma de estudiar la genética ha progresado notablemente en las últimas décadas. Sus orígenes se remontan al estudio de los caracteres hereditarios, seguido por el descubrimiento de los genes y los cromosomas hasta conocer la estructura del ADN. Este último evento impulsó el desarrollo de la tecnología del ADN recombinante y de la secuenciación masiva y automatizada, los cuales permitieron determinar posterior-mente la anatomía de los genomas. Todos estos descubrimientos han promovido la evolución de la biomedicina hacia las eras genómica y posgenómica en las que el uso de la genética reversa impera sobre la genética básica o directa. Además, surge la genética molecular, la genómica funcional y las diversas tecnologías -ómicas- que en conjunto pretenden comprender de manera integral la función de todos los componentes del genoma y sus productos. La biogerontología, disciplina que estudia los mecanismos biológicos del envejecimiento, es uno de los campos que se han desarrollado notoriamente en los últimos 15 años y refleja los avances científicos de la era posgenómica. Actualmente se han identificado varios gerontogenes y vías moleculares que modifican longevidad y regulan procesos y enfermedades relacionadas con envejecimiento. Dentro de estos genes se encuentran las sirtuinas, una familia de genes conservada evolutivamente que codifica para proteínas con actividad de desacetilasa dependiente de NAD+ y que tienen un papel importante en envejecimiento. En este trabajo revisamos diferentes aproximaciones de genética reversa que se han empleado para identificar algunas de las funciones de estos genes en mamíferos.
The way to study genetics has notably progressed in the last decades. Their origins date back to the study of hereditary features, followed by the discovery of genes and chromosomes up to the knowledge of DNA structure. This last event led to the development of recombinant DNA technology and the massive and automated sequencing, which allowed later to determine the anatomy of genomes. All of these discoveries have pushed the evolution of biomedicine towards the genomic and postgenomic eras, in which the use of reverse genetics prevails over the basic or direct one. Furthermore, it emerges the molecular genetics, the functional genomics and the diverse -omics- technologies that together pretend to understand, in an integrative way, the function of all of the genome components and its products. Biogerontology, discipline that studies the biological mechanisms of aging, is one of the fields that has developed notoriously in the last 15 years and reflects the scientific advances of the postgenomic era. Currently, there have been identified several gerontogenes and molecular pathways that modify and regulate age-related processes and diseases. Among these genes are the sirtuins, an evolutionarily preserved family of genes, which codify for proteins with NAD+ dependent deacetylase activity and that play an important role on aging. In this work, we review different reverse genetics approaches that have been used in order to identify some of the functions of these genes in mammals.
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Objective To assess the adhesive behavior of dual-targeted microbubbles carrying both Sialyl Lewisx and anti-ICAM-1 monoclonal antibodies in vitro. Methods Selectin-targeted (with Sialyl Lewisx) microbubbles (MB-S),ICAM-1-targeted (with anti-ICAM-1 monoclonal antibodies) microbubbles (MB-Ⅰ),and dual-targeted (with both ligands) microbubbles(MB-D) were prepared by attaching the ligands to the biotinylated lipid-microbubbles via multi-step avidin biotin bridging chemistry. A parallel plate flow chamber combined with a novel automated tracking algorithm,were used to analyze the transient velocities,rolling and firmly adherent numbers of microbubbles at various shear stress (0. 6,2.0 and 4.0 dyn/cm2)over 6 min. Microbubbles detachments were tested by ramping up the shear stress at 30 s intervals. Results At 0.6 dyn/cm2 shear stress, the rolling numbers of MB-S and MB-D were remarkably more than that of MB-I( P＜0.05), while at 2.0 and 4.0 dyn/cm2 MB-S performed higher rolling efficiency as compared with either MB-I and MB-D ( P＜ 0.05). In all flow conditions, the adhesive numbers of MB-D to the targets were obviously greater than those of MB-S and MB-I ( P＜ 0.05). Half-maximal detachment decreased gradually in MB-I, MB-D and MB-S by turns ( P＜ 0.05). Conclusions MB-I, MB-S and MB-D have different adhesive behaviors. MB-I exhibites primarily firm adhesion with low rolling efficiency, while MB-S reveales unstable or transient adhesion with high rolling efficiency,and MB-D exhibites firm adhesion with high rolling efficiency. MB-D may be suitable for molecular imaging in high-flow vessels.
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Objective To prepare the liver targeting nano-liquid perfluorocarbon ultrasound contrast agent and observe its general characteristics;to observe the targeting combined effects of the human liver cells L02 and the targeted ultrasound contrast agent ;to evaluate the gathering imaging effects of the targeted ultrasound contrast agent. Methods Amine method was used to prepared asialoglycoprotein Gal specific ligand polylysine (Gal-PLL), rotary evaporator and sonicated liquid fluorocarbon were used to prepare nano lipid ultrasound contrast agent. Human liver cell L02 were cultured, the combined effects were observed according to the reacting time of the cells and the targeted nano-lipid ultrasound contrast agent. The nanolipid ultrasound contrast agent and the degassed_ water_ were loaded into cysts and their ultrasound imaging effects were observed by ultrasound diagnostic apparatus Philips iU22. Results The particle size of the liquid fluorocarbon nano-targeted lipid ultrasound contrast agent was extremely small, uniform, cylindrical and spherical. The cysts in vitro showed that the side of the targeted liquid perfluorocarbon nano-lipid ultrasound contrast agent showed high echo. Conclusions The targeted liquid perfluorocarbon nano-lipid ultrasound contrast agent can be effectively targeted to the human liver cells L02 due to carrying home-made Gal-PLL. The targeted ultrasound contrast agents can be imaging by ultrasound and be confirmed in vitro.The size of the contrast agent was small, therefore, it can be considered an ideal ultrasonic molecular probe and achieve the ultrasound molecular imaging in cell level.
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Carrying out targeting an oncolytic adenovirus strategy in gene therapy of pancreatic cancer is a new direction.Currently,related research including vitro test and animal models vivo test,targeted strategies on molecular biology and gene level are carried out.Some of oncolytic adenovirus drugs have entered phase Ⅲ clinical trials.Oncolytic adenoviruses alone or in combination with other treatments,can enhanced anti-tumor effect.
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Objective To evaluate the adhesion mechanisms and microvascular behaviors of P-selectin targeted microbubbles and isotype control microbubbles.Methods The targeted microbubbles with FITC fluorescence and antibodies of P-selectin (MBp), and the isotype control microbubbles with FITC fluorescence and isotype antibodies(MBiso) were constructed.MBp and MBiso were injected intravenously in random to wild-type mice with TNF-α stimulus.The mechanisms and behaviors of MBp and MBiso in cremasteric venules were assessed by fluorescence microscopy.And then velocity variation of ultrasound microbubbles in microvascular was analyzed by tracking fixed-point technology of image-pro-plus software.Results The retention of microbubbles directly to venular endothelium amounted to (8.4 ± 2.1 )/view in MBp-group,while it was only (0.8 ± 0.8)/view in MBiso-group.Difference was evident between of the two groups( P ＜0.01 ).The numbers of MBp and MBiso attachment to activated leukocytes were (3.6± 0.6)/view and (2.2± 0.8)/view separately.There was no obvious difference between the two groups( P ＞0.05).The variation curves of velocity in MBp and MBiso targeting to venular endothelium were different.The flowing rate decreased gradually in MBp-group,while it decreased rapidly in MBiso-group.Conclusions MBp and MBiso have different behaviors targeting to venular endothelium, MBp could adhere to vascular endothelial efficiently and specifically, these results suggest MBp may be used to assess inflammation of vascular endothelial or other tissue injury effectively.
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MicroRNA-143(miR-143)is a non-coding small RNA composed of approximate 22 nuelcotides,participating in post-transcription gene regulation. MiR-143 is lowly expressed in many human cancer cells. Recent studies show that miR-143 is involved in cell differentiation ,proliferation and apoptosis,closely related to tumorigenesis. Extracellular signal-regulated kinase 5 (ERK5), fibronectin type Ⅲ domain containing 3B(FNDC3B) ,DNA methyltranferase 3A(DNMT3A) ,and K-ras are putative targets of miR-143. MiR-143 plays a role in the mechanism of tumor growth, invasion, metastasis, and drug resistance by regulating target genes. Furthermore,the combining therapy of miR-143 and antitumor drug will open a novel approach for the treatment of tumor.
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Objective To prepare a new kind of targeted liposome ultrasound contrast agent with small peptide K237 as the ligand which can combine specifically with KDR which is the main receptor of VEGF.and to test its capability in vitro. Methods Targeted bubbles(P-Bio-Av-Bio-Mbs) were formed through "biotin-avidin" bridge grafting, then they were incubated respectively with LOVO, HUVECs and LS174T which were KDR positive or negative expressed in various cells,meanwhile incubated LOVO cells with FITC- P-Bio-Av-Bio-Mbs,FITC-P-Mbs and FITC-Mbs respectively. After that, the rosette formation rate and fluorescence intensity of the combination between microbubbles and cells were observed with microscope and fluorescence microscope. After being incubated with small peptide K237 of 10 μg and 50 μg, LOVO cells were incubated with P-Bio-Av-Bio-Mbs for observing the distribution of microbubbles. Results In KDR sharply positive expressed LOVO cells, the surrounding rosette formation rate was as high as 90. 52% with the fluorescence intensity of grade 3, and it was 53. 46% with grade 2 fluorescence intensity rate in KDR positive expressed HUVECs cells, while in KDR negative expressed LS174T cells, there were few microbubbles surrounded with rosette formation rate of 5. 57% and fluorescence intensity rate of grade 0-1, therefore there were significant statistic differences in rosette formation rate among groups ( P < 0.05). After LOVO cells combined with FITC-P-Bio-Av-Bio-Mbs, FITC-P-Mbs and FITC-Mbs respectively,there were significant differences in their rosette formation rate, namely 89.62%, 7. 56% , 0 with the fluorescence rate of 3,0 - 1 and 0 respectively. Targeted cells pretreated with 10 pg K237 showed significant decreased rosette formation,and there was no formation in 50 ?g pretreated group. Conclusions KDR-Targeted liposome contrast agent with small peptide K237 liganded has been successfully prepared through biotin-avidin mediation and could combine specifically and high efficiently with targeted cells in vitro. The KDR-targeted molecular imaging of tumor neovascularizaiton may provide a new approach for early diagnosis of carcinoma.