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Hepatitis B virus core protein (HBc) has become a hot spot in drug carrier protein research due to its natural particle self-assembly ability and ease of modification. The truncation of the C-terminal polyarginine domain (CTD, aa 151-183) of HBc does not affect the self-assembly of the particles. However, it does affect the internal and external charges of the particles, which may subsequently affect drug encapsulation. Thus, the truncated C-terminal polyarginine domain (CTD) of HBc and the inserted RGD peptide were selected to construct and express three HBc variants (RH) encapsulated with ICG (RH/ICG) with different C-terminal lengths to compare the stability and drug activity of their nanoformulations. RH160/ICG was found to have a great advantages in encapsulation efficiency and biological imaging. Compared with other HBc variants, RH160/ICG significantly improved encapsulation efficiency, up to 32.77%±1.23%. Cytotoxicity and hemolysis assays further demonstrated the good biocompatibility of RH160/ICG. Cell uptake and in vivo imaging experiments in mice showed that RH160/ICG could efficiently deliver ICG in tumor cells and tumor sites with good imaging effect. This research provides a new direction for further expanding the diagnosis and treatment application of ICG and development of HBc-based nanoparticle drug carrier platform.
Subject(s)
Animals , Mice , Hepatitis B/drug therapy , Hepatitis B Core Antigens , Indocyanine Green/chemistry , Nanoparticles/chemistry , Viral Core ProteinsABSTRACT
@#The development of living cell drugs and their successful application in clinical treatments require full clarification of the fate of cells after transplantation, which is critical to the safety and efficacy of living cell drugs.In order to solve this problem, cell imaging technology has come into our sight, and the use of visualization technology for non-invasive tracing of living cell drugs could reveal the distribution, homing and activity of living cell drugs in the body, which helps to determine the best number of transplanted cells, optimize the administration scheme, improve the transplantation efficiency, enhance the targeting of transplanted cells, and reduce the potential off-target accumulation risk.This paper summarizes the research advances of non-invasive visual tracing in vivo for living cell drugs from the perspectives of radionuclide imaging, magnetic resonance imaging, magnetic particle imaging, computed tomography imaging, fluorescence imaging and multimodal imaging.The aim is to obtain the biological behavior of living cell drugs in vivo with the application of appropriate contrast agent and tracing technology, and provide a more reasonable scientific basis for the research and development of living cell drugs and their transplantation therapy.
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Liver disease is one of the main causes of human deaths in the world. Orthotopic liver transplantation is the most effective treatment for severe liver diseases, such as liver cirrhosis, hepatocellular carcinoma, etc. However, liver transplantation was limited because of donors shortage, and immunological. In recent years, stem cell therapy with the ability of multi-directional differentiation has potential application value in the treatment of patients with liver diseases. However, the mechanisms of stem cell therapy have not yet been fully understood. Stem cells can be detected under in vivo cell imaging. It can noninvasively trace the distribution, migration, proliferation and differentiation of stem cells, and it is an important link to study the mechanism of stem cells in the treatment of liver diseases. Therefore, this review briefly introduces the latest research progress of stem cell in vivo imaging techniques in the field of stem cell diagnosis and treatment of liver diseases.
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Microglia play multiple roles in such processes as brain development, homeostasis, and pathology. Due to their diverse mechanisms of functions, the complex sub-classifications, and the large differences between different species, especially compared with humans, very different or even opposite conclusions can be drawn from studies with different research models. The choice of appropriate research models and the associated tools are thus key ingredients of studies on microglia. Mice are the most commonly used animal models. In this review, we summarize in vitro and in vivo models of mouse and human-derived microglial research models, including microglial cell lines, primary microglia, induced microglia-like cells, transgenic mice, human-mouse chimeric models, and microglial replacement models. We also summarize recent developments in novel single-cell and in vivo imaging technologies. We hope our review can serve as an efficient reference for the future study of microglia.
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Besides the advantages of high sensitivity, non-invasive, and real-time imaging that the general optical imaging technologies have, the second near-infrared (1 000-1 700 nm) in vivo imaging is regarded as one of the most promising optical imaging technologies in clinical applica-tion at present due to its advantages such as low autofluorescence background, deep tissue penetration and clear imaging. In the second near-infrared imaging system, the fluorescence probe is the most critical technical difficulty and the current research hotspot. Thereinto, due to the unique physical and chemical properties of nanomaterials, the second near-infrared fluorescent nanoprobe is an ideal contrast agent for the current second near-infrared optical imaging technology. The reported inorganic materials that can be used as the second near-infrared fluores-cent nanoprobes include quantum dots, rare earth nanoparticles, and single-walled carbon nanotubes, and the reported organic materials are mainly conjugated polymers. In this paper, the research progresses of the second near-infrared fluorescence nanoprobes mentioned above are re-viewed in order to better understand their application to the field of biomedicine, and promote the further research and clinical application of the second near-infrared in vivo imaging to the biomedical field.
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Tumor tissue is highly heterogeneous and complex in structure. Numerous barriers make it difficult for anti-tumor drugs to reach the center of the tumor tissue, which affects the efficacy. Currently, various strategies to improve intra-tumoral drug delivery are emerging in an endless stream, but the clinical conversion efficiency is low. Hence, it is essential to improve the early evaluation system of intra-tumoral drug delivery. Reasonable evaluation of intra-tumoral drug delivery can rely on three-dimensional cell models, in-vivo imaging technology and appropriate mathematical model to comprehensively reveal the drug delivery process in tumor tissues, predict and screen various influencing factors, and feedback to guide the optimization of intra-tumoral delivery of drugs. This article reviews the evaluation methods of intra-tumoral delivery of anti-tumor drugs, aiming to evaluate the transport of anti-tumor drugs in tumor tissues more accurately and reasonably, and to provide reference and ideas for the synthesis, preparation design, drug combination and optimization of clinical drug regimen of anti-tumor drugs.
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Objective@#To evaluate the effectiveness of reactive oxygen species (ROS)-responsive nanomedicine in suppressing corneal neovascularization (CNV) in vivo.@*Methods@#ROS-responsive nanomedicine (ROS-TK-5/siVEGF), which consists of vascular endothelial growth factor (VEGF) small interfering RNA (siRNA) and thioketal linkage was synthesized by the Michael addition.The cumulative release of siVEGF from nanomedicine under oxidant conditions was assessed by agarose gel electrophoresis.Thirty-nine VEGFR2-luc-KI transgenic mice were used in this study, of which 30 mice were randomly divided into a normal control group, a PBS control group, an ROS-TK-5/NC group, an ROS-TK-5/siVEGF group, and a ranibizumab group, with 6 mice in each group.The ROS levels in the corneal tissue after alkali burning were tested by dihydroethidium (DHE) staining in the other 9 mice.In each group, alkali-burned mice were subconjunctivally injected with 10 μl of a different formula every two days.The effectiveness of nanomedicine in attenuating CNV was evaluated by slit-lamp microscopy and an in vivo imaging system (IVIS) at 7, 14, and 21 days after alkali burning. The use and care of the animals complied with the Statement of the Association for Research in Vision and Ophthalmology (ARVO) and the Guidelines of the Animal Experimental Committee of Liberation Army General Hospital.The study protocol was approved by the Ethics Committee of Liberation Army General Hospital (No.2018-X14-82).@*Results@#After treathrent with an aqueous solution without ROS, only 5%-10% of the siVEGF was released from the nanoparticles within 10 hours.In contrast, about 70% of the siVEGF was released from the nanoparticles after treatment with 10 mmol/L H2O2 within 10 hours.The relative fluorescent intensities in the corneal stromal layer at 7 days and 14 days after alkali burning were 5.403±0.306 and 2.930±0.255, respectively, which was significantly greater than those in the normal control group (1.003±0.015) (both at P<0.05). The CNV areas were statistically different among the four groups at various time points (Fgroup=49.855, P<0.01; Ftime=65.556, P<0.01). The CNV area was significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared with the PBS control and ROS-TK-5/NC groups at 7 days and 14 days after modeling, and the CNV area was more effectively reduced in the ROS-TK-5/siVEGF group than the ranibizumab group at 7 days and 14 days after modeling (all at P<0.05). At day 21 after modeling, the CNV area was significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups (all at P<0.05). IVIS showed that the corneal fluorescent intensity was statistically different among the four groups at various times (Fgroup=27.193, P=0.003; Ftime=51.062, P<0.01). The corneal fluorescent intensities were significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups at 7 days and 14 days after modeling; in addition, the corneal fluorescent intensity was more effectively reduced in the ROS-TK-5/siVEGF group in comparison with the ranibizumab group at 7 days and 14 days after modeling (all at P<0.05). At 21 days after modeling, the corneal fluorescent intensity was significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups (all at P<0.05).@*Conclusions@#ROS-TK-5/siVEGF nanomedicine effectively attenuates alkali burn-induced CNV formation and appears to have a better effect in comparison with ranibizumab at an early stage.
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Objective To evaluate the effectiveness of reactive oxygen species (ROS)-responsive nanomedicine in suppressing corneal neovascularization (CNV) in vivo.Methods ROS-responsive nanomedicine (ROS-TK-5/siVEGF),which consists of vascular endothelial growth factor (VEGF) small interfering RNA (siRNA) and thioketal linkage was synthesized by the Michael addition.The cumulative release of siVEGF from nanomedicine under oxidant conditions was assessed by agarose gel electrophoresis.Thirty-nine VEGFR2-1uc-KI transgenic mice were used in this study,of which 30 mice were randomly divided into a normal control group,a PBS control group,an ROS-TK-5/NC group,an ROS-TK-5/siVEGF group,and a ranibizumab group,with 6 mice in each group.The ROS levels in the corneal tissue after alkali burning were tested by dihydroethidium (DHE) staining in the other 9 mice.In each group,alkali-burned mice were subconjunctivally injected with 10 μl of a different formula every two days.The effectiveness of nanomedicine in attenuating CNV was evaluated by slit-lamp microscopy and an in vivo imaging system (IVIS) at 7,14,and 21 days after alkali burning.The use and care of the animals complied with the Statement of the Association for Research in Vision and Ophthalmology (ARVO) and the Guidelines of the Animal Experimental Committee of Liberation Army General Hospital.The study protocol was approved by the Ethics Committee of Liberation Army General Hospital (No.2018-X14-82).Results After treathrent with an aqueous solution without ROS,only 5％-10％ of the siVEGF was released from the nanoparticles within 10 hours.In contrast,about 70％ of the siVEGF was released from the nanoparticles after treatment with 10 mmol/L H2O2 within 10 hours.The relative fluorescent intensities in the corneal stromal layer at 7 days and 14 days after alkali burning were 5.403±0.306 and 2.930±0.255,respectively,which was significantly greater than those in the normal control group (1.003±0.015) (both at P＜0.05).The CNV areas were statistically different among the four groups at various time points (Fgroup =49.855,P＜0.01;Ftime =65.556,P＜0.01).The CNV area was significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared with the PBS control and ROS-TK-5/NC groups at 7 days and 14 days after modeling,and the CNV area was more effectively reduced in the ROS-TK-5/siVEGF group than the ranibizumab group at 7 days and 14 days after modeling (all at P＜0.05).At day 21 after modeling,the CNV area was significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups (all at P＜ 0.05).IVIS showed that the corneal fluorescent intensity was statistically different among the four groups at various times (Fgroup =27.193,P =0.003;Ftime =51.062,P ＜ 0.01).The corneal fluorescent intensities were significantly reduced in the ROS-TK-5/siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups at 7 days and 14 days after modeling;in addition,the corneal fluorescent intensity was more effectively reduced in the ROS-TK-5/siVEGF group in comparison with the ranibizumab group at 7 days and 14 days after modeling (all at P＜ 0.05).At 21 days after modeling,the corneal fluorescent intensity was significantly reduced in the ROS-TK-5/ siVEGF and ranibizumab groups compared to the PBS control and ROS-TK-5/NC groups (all at P ＜ 0.05).Conclusions ROS-TK-5/siVEGF nanomedicine effectively attenuates alkali burn-induced CNV formation and appears to have a better effect in comparison with ranibizumab at an early stage.
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Objective To investigate the effects of adoptive reinfusion of regulatory T cell (Treg) on the recovery of islet function and graft survival time after islet allograft transplantation. Methods The diabetic model was established using C57BL/6 mice as recipients, and Balb/c mice were chosen as donors for islet allografts transplantation beneath the renal capsule. The recipient mice were divided into 3 groups and 3 mice in each group according to different processing Methods: Treg experiment group (Treg group, 1×106 Treg cells were injected via tail vein at 1 d before operation), positive control group [sirolimus (SRL) group, SRL at a dose of 300 μg/(kg·d) was intragastrically given every day from 1 d before operation] and blank control group (control group, an equivalent volume of normal saline was intragastrically given every day from 1 d before operation). Enzyme-linked immune absorbent assay (ELISA) was used to detect the changes of blood glucose and C-peptide in mice within 14 days after transplantation. In vivo imaging technique was used to dynamically monitor the survival of mice within 14 days after transplantation. Results In each group, the blood glucose levels at postoperative 3 d were significantly decreased compared with those before transplantation (all P < 0.001). At postoperative 1 d, the C-peptide levels showed an explosive rise to varying degree in each group. At postoperative 3 d, the C-peptide levels in each group were significantly higher than that before operation (all P < 0.001). At the end of the observation period at 14 d after operation, the C-peptide levels in the SRL and Treg groups were (427±50) pmol/L and (833±57) pmol/L, relatively higher than that in the control group. But the blood glucose levels were (14.5±0.5) mmol/L and (12.1±0.6) mmol/L, significantly lower than that in the control group (all P < 0.001). Compared with the SRL group, the explosive release amount of C-peptide was significantly lower, the declining trend was more remarkably stable, and the C-peptide level was considerably higher in the Treg group at the end of the observation period (all P < 0.001). At postoperative 14 d, the grafts were almost completely apoptotic in the control group, over 50% of the grafts survived in the SRL group, and over 80% of the grafts survived in the Treg group. Conclusions Adoptive reinfusion of Treg cells can effectively protect islet grafts, prolong the survival time of grafts, and maintain the normal levels of blood glucose and C-peptide in the recipient mice.
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PURPOSE: This study was carried out to identify a peptide that selectively binds to kidney injury molecule-1 (KIM-1) by screening a phage-displayed peptide library and to use the peptide for the detection of KIM-1overexpressing tumors in vivo. MATERIALS AND METHODS: Biopanning of a phage-displayed peptide library was performed on KIM-1–coated plates. The binding of phage clones, peptides, and a peptide multimer to the KIM-1 protein and KIM-1–overexpressing and KIM-1–low expressing cells was examined by enzyme-linked immunosorbent assay, fluorometry, and flow cytometry. A biotin-peptide multimer was generated using NeutrAvidin. In vivo homing of the peptide to KIM-1–overexpressing and KIM1–low expressing tumors in mice was examined by whole-body fluorescence imaging. RESULTS: A phage clone displaying the CNWMINKEC peptide showed higher binding affinity to KIM-1 and KIM-1–overexpressing 769-P renal tumor cells compared to other phage clones selected after biopanning. The CNWMINKEC peptide and a NeutrAvidin/biotin-CNWMINKEC multimer selectively bound to KIM-1 over albumin and to KIM-1–overexpressing 769-P cells and A549 lung tumor cells compared to KIM-1–low expressing HEK293 normal cells. Co-localization and competition assays using an anti–KIM-1 antibody demonstrated that the binding of the CNWMINKEC peptide to 769-P cells was specifically mediated by KIM-1. The CNWMINKEC peptide was not cytotoxic to cells and was stable for up to 24 hours in the presence of serum. Whole-body fluorescence imaging demonstrated selective homing of the CNWM-INKEC peptide to KIM-1–overexpressing A498 renal tumor compared to KIM1–low expressing HepG2 liver tumor in mice. CONCLUSION: The CNWMINKEC peptide is a promising probe for in vivo imaging and detection of KIM-1‒overexpressing tumors.
Subject(s)
Animals , Mice , Bacteriophages , Clone Cells , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Fluorometry , Kidney Neoplasms , Kidney , Liver , Lung , Mass Screening , Optical Imaging , Peptide Library , PeptidesABSTRACT
Objective@#To establish a nude mouse model of subcutaneous lung cancer using dual fluorescence reporting genes of luciferase (Luc) and near-infrared fluorescent protein (iRFP).@*Methods@#The Luc and iRFP expressed lentiviral vector was constructed by Gateway method. After verified by sequencing, the lentivirus particle was prepared and infected into lung cancer A549 cells. Successfully infected A549 (mA549) cells were selected by puromycin and amplified. The expression of Luc and iRFP were observed under fluorescence microscope, and the expression of c-Met protein on the cell surface was detected by immunofluorescence. Twelve female nude mice were randomly divided into 2 groups, 6 in each group. A549 and mA549 cells were inoculated subcutaneously into the right forelimb of nude mice. The growth and fluorescence expression of the tumor were observed by in vivo imaging. The tumor formation was evaluated by hematoxylin-eosin (HE) staining and immunohistochemistry.@*Results@#The Luc and iRFP stably expressed mA549 cell line was successfully constructed. The expressions of iRFP and Luc in mA549 cells were observed under fluorescence microscope. The results of immunofluorescence showed that c-Met protein expressed in both A549 cells and mA549 cells. The growth period of mA549 xenograft in nude mice was moderate and the tumorigenesis rate was 100%. The growth trend of mA549 cells in vivo was not significantly different from that of A549 cells (P>0.05). HE staining and immunohistochemistry results showed that the tumor issues displayed typical histopathological features of tumor. Immunohistochemistry results showed that both A549 and mA549 tumors expressed c-Met protein.@*Conclusion@#A stable, real-time monitoring model of iRFP-Luc-A549 lung cancer cell xenograft in nude mice was successfully constructed.
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Objective: To evaluate the effect of two-photon in vivo imaging on detecting the blood brain barrier (BBB) injury in the ultra-early stage of cerebral ischemic stroke. Methods: Twelve clean grade C57BL/6 healthy male mice aged 8-12 weeks were randomly divided into Sham group and middle cerebral artery occlusion (MCAO) group,which were sham operated or middle cerebral artery occluded,respectively. After 60 min of ischemia,MCAO mice were treated with reperfusion for 30-60 min after the suture being removed. The vessels and the neutrophils of mice in the two groups were labeled intravenously with Alexa-Fluora-488 conjugated dextran and rhodamine 6G,respectively. The integrity of BBB was detected by intravenous injection of tetramethylrhodamine-5-maleimide (TMR). Before and after the stroke,the real-time changes of the fluorescence intensity of the inside and outside cerebral vessels of mice in the MCAO group were observed by two-photon fluorescence microscopy. Results: The fluorescence intensity of TMR in the external cerebrovascular of mice in the MACO group was significantly increased within 30-60 min after stroke (P=0.000),suggesting there existed tracer leakage. Compared with the Sham group,the movement of neutrophils in the blood vessels of mice in the MACO group was significantly slowed down (P=0.000). Conclusion: Two-photon in vivo imaging can be used to detect the BBB injury in the ultra-early stage of cerebral ischemic stroke,which provides a certain reference value for clinical application.
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Objective: Human hepatoma SMMC-7721 cells were transplanted into nude mice to study the tissue distribution of nanostructured lipid carrier modified by hyaluronic acid (HA-OUR-NLC) loaded with three components in Panax ginseng (oleanolic acid, ursolic acid, and ginsenosider Rg3, OUR). Methods: FITC and DiR were used as fluorescent probes to dynamically monitor the HA-OUR-NLC targeted behavior of various tissues and organs through fluorescence endoscopic confocal imaging and in vivo imaging studies. Results: RUE values of oleanolic acid, ursolic acid, and ginsenosider Rg3 in tumors were significantly increased in HA-OUR-NLC group, reaching 2.51 ± 1.23, 2.27 ± 1.43, and 2.77 ± 0.25, respectively, which indicated that nanoparticles modified by hyaluronic acid could enhance drug uptake in tumors. The DiR accumulation in tumors of DiR-HA-OUR-NLC was higher than that of DiR-OUR-NLC by the visualized fluorescence of in vivo imaging. Conclusion: It indicated that nanoparticles modified by hyaluronic acid loaded with three components in P. ginseng can be enriched in the tumor site of liver cancer, which is in line with the expectation and can significantly improve the tumor targeting of the drug delivery system.
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The multiple drug delivery system of components of traditional Chinese medicine is a system composed of multiple components and multiple units. According to the characteristics of each component, different drug delivery units are designed and combined to achieve the purpose of improving bioavailability and enhancing drug efficacy. In this study, supercritical extracts, phenolic acids, and polysaccharides derived from Angelica sinensis were examined as research objects, and a pellet-based vehicle was applied to construct a multiple drug delivery system for the treatment and chemoprevention of colitis and colorectal cancer. The extrusion-spheronization method was used to prepare pellets of Angelica polysaccharides which should be released in the stomach. The yield in 18-24 mesh and plane critical angle served as the index. The Box-Behnken design and the orthogonal design were used to optimize the formulation and parameters of pellets. According to a previous study, the colon specific pellets loading supercritical extracts and phenolic acid extracts were prepared by the optimized process. These two units of pellets were combined into the multiple drug delivery system of effective components of Angelica sinensis, and the quality evaluation and in vitro release study were conducted. The dynamic observation of pellets in mice was evaluated using small animal in vivo imaging system. The prescription of the Angelica polysaccharides gastric releasing pellets was:microcrystalline cellulose 6.5 g, polysaccharide 3.3 g, silica 0.2 g and 7 mL of 60% ethanol as wetting agent. The process parameters were as follows:extrusion rate at 75 r·min-1, rounding rate at 1 800 r·min-1, and rounding time for 3 min. Both in vivo and in vitro studies indicate that the prepared multiple drug delivery system of effective components of Angelica sinensis produced good release properties. The polysaccharide pellets could be rapidly released in the artificial gastric fluid and in the stomach. The colon specific pellets showed good targeting. They released little in the artificial gastric fluid within 2 hours, released less than 20% in the artificial intestinal fluid for 4 hours, and released more than 90% in artificial colon fluid for 6 hours.
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OBJECTIVE: Poly(lactide-co-glycolide) (PLGA) nanoparticles are promising materials for the development of new drug-releasing systems. The purpose of this study was to evaluate the in vivo retention time of materials loaded in nanoparticles as compared with that of the material alone by in vivo imaging in nude mice. MATERIALS AND METHODS: Mice (n = 20) were injected with 0.1 mL fluorescent material 1,1′-dioctadecyl-3,3,3′,3′ tetramethylindotricarbocyanine iodide (DiR)-loaded PLGA nanoparticles (200 nm) into the right paraspinal muscle, and the same volume of pure DiR solution was injected into the left paraspinal muscle. Fluorescence images were obtained using an in vivo optical imaging system. Fluorescent images were taken 1 day after the injection, and seven more images were taken at 1-week intervals. Image analysis was done with ImageJ program, and one region of interest was chosen manually, which corresponded to the highest signal-intensity area of fluorescence signal intensity. RESULTS: After 7 weeks, 12 mice showed a right-sided dominant signal, representing the DiR loaded PLGA nanoparticles; 5 mice showed a left-side dominant signal, representing the free DiR solution; and 3 mice showed no signal at all beginning 1 day after the injection. During the 7-week period, the mean signal intensities of the free DiR solution and DiR-loaded PLGA nanoparticles diverged gradually. On day 1, the mean signal intensity of free DiR solution was significantly higher than that of DiR-loaded PLGA (p < 0.001). Finally, by week 7, DiR-loaded PLGA express significantly high signal intensity compared with free DiR solution (p = 0.031). CONCLUSION: The results of the current study suggested that therapeutic agents bound to PLGA nanoparticles may exhibit prolonged retention times.
Subject(s)
Animals , Mice , Fluorescence , Mice, Nude , Nanoparticles , Optical Imaging , Paraspinal Muscles , Polyglactin 910ABSTRACT
PURPOSE: Study on the pathogen and the pathogen-related disease require the information at both cellular and organism level. However, lack of appropriate high-quality antibodies and the difference between the experimental animal models make it difficult to analyze in vivo mechanism of pathogen-related diseases. For more reliable research on the infection and immune-response of pathogen-related diseases, accurate analysis is essential to provide spatiotemporal information of pathogens and immune activity to avoid false-positive or mis-interpretations. In this regards, we have developed a method for tracking Francisella tularensis in the animal model without using the specific antibodies for the F. tularensis. MATERIALS AND METHODS: A dual reporter plasmid using GFP-Lux with putative bacterioferritin promoter (pBfr) was constructed and transformed to F. tularensis live vaccine strain to generate F. tularensis LVS (FtLVS)-GFP-Lux for both fluorescence and bioluminescence imaging. For vaccination to F. tularensis infection, FtLVS and lipopolysaccharide (LPS) from FtLVS were used. RESULTS: We visualized the bacterial replication of F. tularensis in the cells using fluorescence and bioluminescence imaging, and traced the spatio-temporal process of F. tularensis pathogenesis in mice. Vaccination with LPS purified from FtLVS greatly reduced the bacterial replication of FtLVS in animal model, and the effect of vaccination was also successfully monitored with in vivo imaging. CONCLUSION: We successfully established dual reporter labeled F. tularensis for cellular and whole body imaging. Our simple and integrated imaging analysis system would provide useful information for in vivo analysis of F. tularensis infection as well as in vitro experiments, which have not been fully explained yet with various technical problems.
Subject(s)
Animals , Mice , Antibodies , Fluorescence , Francisella tularensis , Francisella , Immunodeficiency Virus, Feline , In Vitro Techniques , Methods , Models, Animal , Plasmids , Vaccination , Whole Body ImagingABSTRACT
Objective To evaluate the feasibility of needle-based confocal laser endomicroscopy (nCLE) for imaging of intra-abdominal tissues and organs in rabbit models in vivo. Methods The nCLE miniprobe was inserted through the 19-gauge needle into various intra-abdominal tissues and organs[omentum majus, liver, pancreas and psoas major (skeletal muscle)]. The nCLE images were acquired and real-time sequences of respective locations were recorded. Finally, nCLE image characteristics were compared with histopathologic findings. Results nCLE was successfully performed in intra-abdominal tissues and organs of five rabbit models. The microscopic structures of cells, glands and microvessels in the omentum majus, liver, pancreas and psoas major ( skeletal muscle) were visualized clearly, respectively. Characteristics of various intra-abdominal tissues and organs were displayed on nCLE images, which were correlated well with histological findings. Conclusion Imaging of intra-abdominal tissues and organs with nCLE in vivo is feasible in future clinical practice.
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@#Objective To observe the growth of orthotopic transplanted tumor in nude mice after stomatin-like protein 2 (SLP-2) expression decreased, and to further study the role of SLP-2 in the development and progression of esophageal squamous cell carcinoma. Methods Using RNA interference technique, esophageal squamous cell carcinoma cell lines with specific expression of SLP-2 and stable expression of luciferase were established. The healthy female nude mice with weight ranging from 19 to 22 g were randomly divided into 3 groups (n=12), 6 mice were used to establish subcutaneous xenografts, and the other 6 mice were used to establish the orthotopic transplanted tumor model (Group 1: cell infected with SLP-2-1 plasmid; group 2: cell infected with SLP-2-2 plasmid; group 3: cell infected with SHGFP plasmid). Index of the experiment end was weight loss and poor general situation in any mouse. Before the nude mice were sacrificed, the luciferase value of the tumor was detected by using in vivo imaging technique. After the nude mice were sacrificed, the primary tumor was removed for pathology examination. Results There was no significant difference in region of interest (ROI) value between the group 1 and group 2 (P=0.943). The ROI value for both groups 1 and 2 was significantly lower than that in the group 3 (P=0.002, P=0.000). The primary tumor infiltrated into the muscularis propria of esophageal was observed in all groups. Conclusion SLP-2 is involved in the development and progression of esophageal squamous cell carcinoma, and the decrease of SLP-2 expression can inhibit the growth of esophageal squamous cell carcinoma.
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Photoacoustic imaging (PAI) is a newly emerging imaging modality for preclinical and clinical applications. The conventional PAI systems use Q-switched Nd:YAG/OPO (Optical Parametric Oscillator) nanosecond lasers as excitation sources. Such lasers are expensive, bulky, and imaging speed is limited because of low pulse repetition rate. In recent years, the semiconductor laser technology has advanced to generate high-repetitions rate near-infrared pulsed lasers diodes (PLDs) which are reliable, less-expensive, hand-held, and light-weight, about 200 g. In this article, we review the development and demonstration of PLD based PAI systems for preclinical and clinical applications reported in recent years.
Subject(s)
Lasers, SemiconductorABSTRACT
Objective To establish a stable and real-time monitorable nude mouse model of orthotopic glioma xenograft.Methods U251 glioma cell line was infected by a lentiviral vector containing green fluorescent protein (GFP) and luciferase (Luc) gene.Cells stably expressing fluorescence of GFP and Luc were sorted by flow cytometry.CCK-8 test and Transwell tumor invasion and migration assay were used to compare the biological features between the cells stably expressing GFP-Luc fluorescence and cells without fluorescence.Then the cells were implanted intracranially in the right caudate nucleus of athymic Balb/c nude mice to establish the tumor model.The growth of intracerebral tumor was monitored over time by a bioluminescence imaging (BLI) system.Hematoxylin-eosin (HE) staining was used to evaluate the histopathological features and tumorigenicity of the transplanted glioma cells in the brain of nude mice.Results U251 glioma cell line with stably expressing GFP-Luc fluorescence and the corresponding orthotopic xenograft model were successfully established.There was no statistically significant difference in the proliferation,invasion and migration abilities between the cells with stably expressing GFP-Luc fluorescence and the control cells.This model showed a high tumor formation rate and stable tumor growth,and takes a moderate time to establish this model.Conclusions Compared with the traditional glioma cells,GFP-Luc-transfected human glioma cells are more feasible for the studies of glioma in vivo.The tumor growth and pathological characteristics in this U251-GFP-Luc glioma model are similar to human glioma,and the growth of this tumor can be real-time monitored.It can be used as an ideal animal model for experimental studies of glioma.