Mr Monoclonal Antibody Targeted Contrast Agent Experiments

Experimental study on MR monoclonal antibodytargeted contrast agentAbstractIn MR diagnosis, the problem of differentiate benign tumor from malignancant tumor is often confronted,the MR tumor-specific contrast agent can differentiate tumor and in the early in the detection of metastatic lymphadenopathy and others metastatic.CL-3 monoclonal antibody-coated magnetite nanoparticles was used,to evaluated optimal measures for the preparation of nanoparticles.The contast study on McAb-PMP and McAb-DMP was assessed. McAb-PMP was labeled with Na?11 using the Iodogen method,The distribution and radioimmunoimaging of 131j.. McAb-PMP in nude mice bearing human colonic cancer were carried out.the contrast enhancement of tissue-specificity with McAb-PMP was observed.The competition-constraint contrast enhancement was carried out.The major results of this study are as follows:1 .polyethyleneglycol(PEG)-magnetite (PMP) consisting of magnetite particles and PEG with terminal carboxy or amino groups and dextran-magnetite particle (DMP) were prepared.Influence of preparation conditions on effective diameters of McAb-PMP and McAb-DMP nanoparticles was unanimous.The content of magnetite of McAb-PMP was luger than that of McAb-PMP.It reduces monoclonal antibody concentration in MR animal experimental study.2.A nude mice model with bearing LS- 174 cell derived from human colonic cancer and QGY-7703 cell from hepatocarcinoma were established.The CEA experssion high positive of LS-l74T cells and tumorxenograft was measured by immunohistochemistry.It is basis of biodistribution and MR contast enhancement of McAb-PMP.3.The immunoactivity of 1311-McAb-PMP with Iodogen method was not changed.It is efficacious,convenient,credibility method for study of immunological magnetite nanoparticles distribution.The method avoids isotopes at the begin of immunological magnetitic nanoparticles prepartion experiment.Immunoactivity of ?11-McAb-PMP meets the stardard of radioimmunoimaging.Satisfactory imaging was obtained at 48th hour after injection and becoming more clearly.RII and N/NT was unanimous.4.McAb-PMP shows significant reducing of signal intensity of colonic cancer on SE T2WI, The enhancing effect of McAb-PMP compared with that of the contrast group.Because of McAb-PMP immunoreactive with CEA antigen of colon cancer, magnetite nanoparticles changes relaxativity. The competition-constraint contrast enhancement shows that McAb-PMP conjugate CEA antigen of tumor.The new monoclonal antibody-coated targeted MR contrast agents for colonic cancer was prepared.5.Targeting MRI is probably a feasible and promising modality in the early detection of cancer and their metastises. The result of present study laid foundation for future study of using peptide labeled magnetite targeted others cancer.The present study was undergone by O.2T Magneton Open MRI system. Immunological magnetite nanoparticles are potential imaging agents for immunor-specific MR diagnosis, MRII will substitute Rh and has the potential of becoming a new diagnostic method for tumor.