With its abilities of trans-synaptic tracing and self-replication and wide host range, pseudorabies virus (PRV) has been applied in the field of neuroanatomy since the 1970s. Four decades of PRV application have made many advances in researches on neuronal tracing with PRV. Mechanism studies focused on investigating infection of primary neurons and tracing direction in secondary neurons, while application studies focused on development of new pathological strains and innovation of tracing techniques. To date, the mechanism and application of viral tracing are not completely figured out yet. Integration of molecular biology technology will improve the efficiency in related researches.
Animals ; Cell Tracking ; Herpesvirus 1, Suid ; genetics ; physiology ; Humans ; Neurons ; virology ; Pseudorabies ; virology

In cell image sequences, due to the nonlinear and nonGaussian motion characteristics of active cells, the accurate prediction and tracking is still an unsolved problem. We applied extended Kalman particle filter (EKF-PF) here in our study, attempting to solve the problem. Firstly we confirmed the existence and positions of the active cells. Then we established a motion model and improved it via adding motion angle estimation. Next we predicted motion parameters, such as displacement, velocity, accelerated velocity and motion angle, in region centers of the cells being tracked. Finally we obtained the motion traces of active cells. There were fourteen active cells in three image sequences which have been tracked. The errors were less than 2.5 pixels when the prediction values were compared with actual values. It showed that the presented algorithm may basically reach the solution of accurate predition and tracking of the active cells.
Algorithms ; Artificial Intelligence ; Cell Movement ; Cell Tracking ; methods ; Forecasting ; Image Enhancement ; methods ; Image Interpretation, Computer-Assisted ; methods ; Models, Theoretical

The present study aimed to determine the role of tissue injury in migration of mesenchymal stem cells (MSCs) intravenously transplanted into heart and to establish experimental basis for improving stem cell therapy in its targeting and effectiveness. MSCs were isolated from bone marrow of male Sprague-Dawley rats and purified by density centrifuge and adhered to the culture plate in vitro. Female rats were divided randomly into four groups. Myocardial ischemia (MI) transplanted group received MSCs infusion through tail vein 3 h after MI and compared with sham-operated group or normal group with MSCs infusion, or control group received culture medium infusion. MI was created in female rats by ligating the left anterior descending coronary artery. The heart was harvested 1 week and 8 weeks after transplantation. The characteristics of migration of MSCs to heart were detected with expression of sry gene of Y chromosome by using fluorescence in situ hybridization (FISH). Ultrastructural changes of the ischemic myocardium of the recipient rats were observed by transmission electron microscope (TEM). One week or 8 weeks after transplantation, sry positive cells were observed in the cardiac tissue in both of MI transplanted group and sham-operated group, the number of sry positive cells being significantly higher in MI transplanted group (P<0.01). No significant difference was found in the number of sry positive cells between 1 week and 8 weeks after transplantation. No sry positive cells were observed in the hearts of control and normal group. In addition, the ultrastructure of some cells located in the peri-infarct area of MI rats with MSCs transplantation was similar to that of MSCs cultured in vitro. These results indicate that MSCs are capable of migrating towards ischemic myocardium in vivo and the fastigium of migration might appear around 1 week after MI. The tissue injury and its degree play an important role in the migration of MSCs.
Animals ; Cell Movement ; Cell Tracking ; Female ; Male ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; cytology ; Myocardial Ischemia ; therapy ; Myocardium ; ultrastructure ; Rats ; Rats, Sprague-Dawley

Analysis of neural stem cells' movements is one of the important parts in the fields of cellular and biological research. The main difficulty existing in cells' movement study is whether the cells tracking system can simultaneously track and analyze thousands of neural stem cells (NSCs) automatically. We present a novel cells' tracking algorithm which is based on segmentation and data association in this paper, aiming to improve the tracking accuracy further in high density NSCs' image. Firstly, we adopted different methods of segmentation base on the characteristics of the two cell image sequences in our experiment. Then we formed a data association and constituted a coefficient matrix by all cells between two adjacent frames according to topological constraints. Finally we applied The Hungarian algorithm to implement inter-cells matching optimally. Cells' tracking can be achieved according to this model from the second frame to the last one in a sequence. Experimental results showed that this approaching method has higher accuracy compared with that using the topological constraints tracking alone. The final tracking accuracies of average of sequence I and sequence II have been improved 10.17% and 4%, respectively.
Algorithms ; Animals ; Cell Count ; Cell Movement ; Cell Tracking ; statistics & numerical data ; Image Processing, Computer-Assisted ; methods ; Microscopy, Fluorescence ; Models, Theoretical ; Neural Stem Cells ; cytology

PURPOSE: Both human NIS and mutant D2R transgenes are proposed as reporting system in transplanted cell tracking. Using hepatoma cell lines, we constructed a dual reporter system containing human sodium-iodide symporter (hNIS) and dopamine 2 receptor (D2R) and compared its characteristics. MATERIALS AND METHODS: The recombinant plasmid (pIRES-hNIS/D2R) was constructed with IRES (internal ribosome entry site) under control of the CMV promoter. pIRES-hNIS/D2R was transfected to human hepatoma SK-Hep1 cell line with lipofectamine. HEP-ND (SK-Hep1-hNIS/D2R) cells stably expressing hNIS and D2R was established by selection with G418 for two weeks. RT-PCR was performed to investigate the expression of both hNIS and D2R genes. The expressions of hNIS and D2R were measured by 125I uptake assays and receptor binding assays. Specific binding of D2R to [3H]spiperone was verified by Scatchard plot with (+) butaclamol as a specific inhibitor. K (d) and B (max) values were estimated. The correlation between hNIS and D2R expression was compared by using each clone. RESULTS: Similar quantities of hNIS and D2R genes were expressed on HEP-ND as RT-PCR assays. HEP-ND cells showed 30 to 40 fold higher radioiodine uptakes than those of parental SK-Hep1 cells. 125I uptake in HEP-ND cells was completely inhibited by KClO4, a NIS inhibitor. Specific binding to HEP-ND cells was saturable and the K (d) and B (max) values for HEP-ND cells were 2.92 nM, 745.25 fmol/mg protein and 2.91nM, 1323 fmole/mg protein in two clones, respectively. The radioiodine uptake by hNIS activity and D2R binding was highly correlated. CONCLUSION: We developed a dual positron and gamma imaging reporter system of hNIS and D2R in a stably transfected cell line. We expect that D2R and hNIS genes can complement mutually as a nuclear reporting system or that D2R can be used as reporter gene when hNIS gene were used as a treatment gene.
Butaclamol ; Carcinoma, Hepatocellular ; Cell Line ; Cell Tracking ; Clone Cells ; Complement System Proteins ; Dopamine* ; Electrons ; Genes, Reporter ; Humans ; Ion Transport* ; Parents ; Plasmids ; Ribosomes ; Sodium Iodide* ; Sodium* ; Transgenes*

Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic wholebody imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments.
Animals ; Apoptosis ; Cell Proliferation ; Cell Tracking ; Dendritic Cells ; Genes, Reporter ; Immunotherapy ; Lymphocytes ; Macrophages ; Molecular Imaging ; Optical Imaging ; Organothiophosphorus Compounds ; Track and Field

Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic wholebody imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments.
Animals ; Apoptosis ; Cell Proliferation ; Cell Tracking ; Dendritic Cells ; Genes, Reporter ; Immunotherapy ; Lymphocytes ; Macrophages ; Molecular Imaging ; Optical Imaging ; Organothiophosphorus Compounds ; Track and Field

The aim of this study was to label rabbit bone derived mesenchymal stem cells (BMSCs) with superparamagnetic iron oxide particles (SPIO) and to study the effects of magnetic labeling on the multi-differentiation of BMSCs. Rabbit BMSCs were isolated, purified, expanded, then coincubated with SPIO(25 microg/ml) complexed to protamine sulfate (Pro) transfection agents overnight. Prussian blue staining and transmission electron microscopy were performed to show intracellular iron. Cell differentiation was evaluated. Both labeled and unlabeled BMSCs were subjected to osteogenic, adipogenic and chondrogenic differentiation to assess their differentiation capacity for 21 d. Osteogenic cells were stained with alizarin red to reveal calcium deposition, adipogenic cells were stained with oil redO' respectively. Chondrogenic cells stained with Safranin-O, glycosamino glycans, and type II collagen production was assessed by standard immunohistochemistry. Cell with immunohistochemistry staining were detected by polarized light microscopy and analysed by Image-Pro Plus software. The results showed that intracytoplasmic nanoparticles were stained with Prussian blue and observed by transmission electron microscopy clearly except the unlabeled control. As compared with the nonlabeled cells, it showed no statistically significant difference on the differentiation of the labeled BMSCs. And the differentiation of the labeled cells were unaffected by the endosomal incorporation of SPIO. In summary, BMSCs can be labeled with SPIO without significant change in cell multi-differentiation capacity.
Adipocytes ; cytology ; Animals ; Bone Marrow Cells ; cytology ; Cell Differentiation ; physiology ; Cell Proliferation ; Cell Tracking ; Cells, Cultured ; Chondrocytes ; cytology ; Dextrans ; Ferric Compounds ; Magnetite Nanoparticles ; Mesenchymal Stromal Cells ; cytology ; Osteoblasts ; cytology ; Rabbits ; Staining and Labeling

Stem cell therapy is a potentially promising option for erectile dysfunction; however, its risk of tumorigenicity is a clinical hurdle and the risk is positively related to the number of injected cells. Our previous study showed that nanotechnology improved adipose-derived stem cell (ADSC) therapy for erectile dysfunction of cavernous nerve injury (CNI) by attracting cells in the corpus cavernosum. These results indicated the possibility of using a reduced dosage of ADSCs for intracavernous injection. In this exploratory study, we used lower dosage (2 × 10⁵ cells) of ADSCs for intracavernous injection (ICI) and the nanotechnology approach. Intracavernous pressure and mean arterial pressure were measured at day 28 to assess erectile function. The low-dose ADSC therapy group showed favorable treatment effects, and nanotechnology further improved these effects. In vivo imaging of ICI cells revealed that the fluorescein signals of NanoShuttle-bound ADSCs (NanoADSCs) were much stronger than those of ADSCs at days 0, 1, and 3. Both immunofluorescence and Western blot analysis showed a significant increase in smooth muscle, endothelium, and nerve tissue in the ADSC group compared to that in the CNI group; further improvement was achieved with assisted nanotechnology. These findings demonstrate that nanotechnology can be used to further improve the effect of small dosage of ADSCs to improve erectile function. Abundant NanoADSCs remain in the corpus cavernosum in vivo for at least 3 days. The mechanism of erectile function improvement may be related to the regeneration of the smooth muscle, endothelium, and nerve tissues.
Animals ; Cell Tracking ; Disease Models, Animal ; Erectile Dysfunction/therapy* ; Male ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stem Cells ; Penis/innervation* ; Peripheral Nerve Injuries/complications* ; Rats ; Rats, Sprague-Dawley ; Treatment Outcome

BACKGROUND: Mesenchymal stem cells (MSCs) obtained from bone marrow or adipose tissue can successfully repair emphysematous animal lungs, which is a characteristic of chronic obstructive pulmonary disease. Here, we describe the cellular distribution of MSCs that were intravenously injected into mice with elastase-induced emphysema. The distributions were also compared to the distributions in control mice without emphysema. METHODS: We used fluorescence optical imaging with quantum dots (QDs) to track intravenously injected MSCs. In addition, we used a human Alu sequence-based real-time polymerase chain reaction method to assess the lungs, liver, kidney, and spleen in mice with elastase-induced emphysema and control mice at 1, 4, 24, 72, and 168 hours after MSCs injection. RESULTS: The injected MSCs were detected with QD fluorescence at 1- and 4-hour postinjection, and the human Alu sequence was detected at 1-, 4- and 24-hour postinjection in control mice (lungs only). Injected MSCs remained more in mice with elastase-induced emphysema at 1, 4, and 24 hours after MSCs injection than the control lungs without emphysema. CONCLUSION: In conclusion, our results show that injected MSCs were observed at 1 and 4 hours post injection and more MSCs remain in lungs with emphysema.
Adipose Tissue ; Animals ; Bone Marrow ; Cell Tracking ; Emphysema* ; Fluorescence ; Humans ; Injections, Intravenous ; Kidney ; Liver ; Lung ; Mesenchymal Stromal Cells* ; Mice ; Optical Imaging ; Pulmonary Disease, Chronic Obstructive ; Quantum Dots ; Real-Time Polymerase Chain Reaction ; Spleen