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Journal of Magnetic Resonance Imaging :... Jan 2020Differentiation of early postoperative complications affects treatment options after lung transplantation.
Can texture analysis in ultrashort echo-time MRI distinguish primary graft dysfunction from acute rejection in lung transplants? A multidimensional assessment in a mouse model.
BACKGROUND
Differentiation of early postoperative complications affects treatment options after lung transplantation.
PURPOSE
To assess if texture analysis in ultrashort echo-time (UTE) MRI allows distinction of primary graft dysfunction (PGD) from acute transplant rejection (ATR) in a mouse lung transplant model.
STUDY TYPE
Longitudinal.
ANIMAL MODEL
Single left lung transplantation was performed in two cohorts of six mice (strain C57BL/6) receiving six syngeneic (strain C57BL/6) and six allogeneic lung transplants (strain BALB/c (H-2K )).
FIELD STRENGTH/SEQUENCE
4.7T small-animal MRI/eight different UTE sequences (echo times: 50-5000 μs) at three different postoperative timepoints (1, 3, and 7 days after transplantation).
ASSESSMENT
Nineteen different first- and higher-order texture features were computed on multiple axial slices for each combination of UTE and timepoint (24 setups) in each mouse. Texture features were compared for transplanted (graft) and contralateral native lungs between and within syngeneic and allogeneic cohorts. Histopathology served as a reference.
STATISTICAL TESTS
Nonparametric tests and correlation matrix analysis were used.
RESULTS
Pathology revealed PGD in the syngeneic and ATR in the allogeneic cohort. Skewness and low-gray-level run-length features were significantly different between PGD and ATR for all investigated setups (P < 0.03). These features were significantly different between graft and native lung in ATR for most setups (minimum of 20/24 setups; all P < 0.05). The number of significantly different features between PGD and ATR increased with elapsing postoperative time. Differences in significant features were highest for an echo-time of 1500 μs.
DATA CONCLUSION
Our findings suggest that texture analysis in UTE-MRI might be a tool for the differentiation of PGD and ATR in the early postoperative phase after lung transplantation.
LEVEL OF EVIDENCE
1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2020;51:108-116.
Topics: Acute Disease; Animals; Diagnosis, Differential; Disease Models, Animal; Graft Rejection; Image Interpretation, Computer-Assisted; Lung; Lung Transplantation; Magnetic Resonance Imaging; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Primary Graft Dysfunction
PubMed: 31150142
DOI: 10.1002/jmri.26817 -
Frontiers in Immunology 2022Despite advances in treating high-risk neuroblastoma, 50-60% of patients still suffer relapse, necessitating new treatment options. Bispecific trifunctional antibodies...
INTRODUCTION
Despite advances in treating high-risk neuroblastoma, 50-60% of patients still suffer relapse, necessitating new treatment options. Bispecific trifunctional antibodies (trAbs) are a promising new class of immunotherapy. TrAbs are heterodimeric IgG-like molecules that bind CD3 and a tumor-associated antigen simultaneously, whereby inducing a TCR-independent anti-cancer T cell response. Moreover, via their functional Fc region they recruit and activate cells of the innate immune system like antigen-presenting cells potentially enhancing induction of adaptive tumor-specific immune responses.
METHODS
We used the SUREK trAb, which is bispecific for GD2 and murine Cd3. Tumor-blind trAb and the monoclonal ch14.18 antibody were used as controls. A co-culture model of murine dendritic cells (DCs), T cells and a neuroblastoma cell line was established to evaluate the cytotoxic effect and the T cell effector function in vitro. Expression of immune checkpoint molecules on tumor-infiltrating T cells and the induction of an anti-neuroblastoma immune response using a combination of whole cell vaccination and trAb therapy was investigated in a syngeneic immunocompetent neuroblastoma mouse model (NXS2 in A/J background). Finally, vaccinated mice were assessed for the presence of neuroblastoma-directed antibodies. We show that SUREK trAb-mediated effective killing of NXS2 cells in vitro was strictly dependent on the combined presence of DCs and T cells.
RESULTS
Using a syngeneic neuroblastoma mouse model, we showed that vaccination with irradiated tumor cells combined with SUREK trAb treatment significantly prolonged survival of tumor challenged mice and partially prevent tumor outgrowth compared to tumor vaccination alone. Treatment led to upregulation of programmed cell death protein 1 (Pd-1) on tumor infiltrating T cells and combination with anti-Pd-1 checkpoint inhibition enhanced the NXS2-directed humoral immune response.
CONCLUSION
Here, we provide first preclinical evidence that a tumor vaccination combined with SUREK trAb therapy induces an endogenous anti-neuroblastoma immune response reducing tumor recurrence. Furthermore, a combination with anti-Pd-1 immune checkpoint blockade might even further improve this promising immunotherapeutic concept in order to prevent relapse in high-risk neuroblastoma patients.
Topics: Animals; Mice; Immune Checkpoint Inhibitors; Neoplasm Recurrence, Local; Antibodies, Bispecific; T-Lymphocytes; Antineoplastic Agents; Neuroblastoma
PubMed: 36700232
DOI: 10.3389/fimmu.2022.1023206 -
Frontiers in Immunology 2023Established mouse models of HER2+ cancer are based on the over-expression of rodent Neu/Erbb2 homologues, which are incompatible with human HER2 (huHER2) targeted...
BACKGROUND
Established mouse models of HER2+ cancer are based on the over-expression of rodent Neu/Erbb2 homologues, which are incompatible with human HER2 (huHER2) targeted therapeutics. Additionally, the use of immune-deficient xenograft or transgenic models precludes assessment of native anti-tumour immune responses. These hurdles have been a challenge for our understanding of the immune mechanisms behind huHER2-targeting immunotherapies.
METHODS
To assess the immune impacts of our huHER2-targeted combination strategy, we generated a syngeneic mouse model of huHER2+ breast cancer, using a truncated form of huHER2, HER2T. Following validation of this model, we next treated tumour-bearing with our immunotherapy strategy: oncolytic vesicular stomatitis virus (VSVΔ51) with clinically approved antibody-drug conjugate targeting huHER2, trastuzumab emtansine (T-DM1). We assessed efficacy through tumour control, survival, and immune analyses.
RESULTS
The generated truncated HER2T construct was non-immunogenic in wildtype BALB/c mice upon expression in murine mammary carcinoma 4T1.2 cells. Treatment of 4T1.2-HER2T tumours with VSVΔ51+T-DM1 yielded robust curative efficacy compared to controls, and broad immunologic memory. Interrogation of anti-tumour immunity revealed tumour infiltration by CD4+ T cells, and activation of B, NK, and dendritic cell responses, as well as tumour-reactive serum IgG.
CONCLUSIONS
The 4T1.2-HER2T model was used to evaluate the anti-tumour immune responses following our complex pharmacoviral treatment strategy. These data demonstrate utility of the syngeneic HER2T model for assessment of huHER2-targeted therapies in an immune-competent setting. We further demonstrated that HER2T can be implemented in multiple other syngeneic tumour models, including but not limited to colorectal and ovarian models. These data also suggest that the HER2T platform may be used to assess a range of surface-HER2T targeting approaches, such as CAR-T, T-cell engagers, antibodies, or even retargeted oncolytic viruses.
Topics: Humans; Mice; Animals; Female; Ado-Trastuzumab Emtansine; Breast Neoplasms; Trastuzumab; Rhabdoviridae; Antibodies, Monoclonal, Humanized; Disease Models, Animal
PubMed: 37153626
DOI: 10.3389/fimmu.2023.1181014 -
Journal of Hepatology Nov 2018A major limitation in the field of liver transplantation is the shortage of transplantable organs. Chimeric animals carrying human tissue have the potential to solve...
BACKGROUND & AIMS
A major limitation in the field of liver transplantation is the shortage of transplantable organs. Chimeric animals carrying human tissue have the potential to solve this problem. However, currently available chimeric organs retain a high level of xenogeneic cells, and the transplantation of impure organs needs to be tested.
METHODS
We created chimeric livers by injecting Lewis rat hepatocytes into C57Bl/6 mice, and further transplanted them into newly weaned Lewis rats (45 ± 3 g) with or without suboptimal immunosuppression (tacrolimus 0.6 mg/kg/day for 56 or 112 days). Control donors included wild-type C57Bl/6 mice (xenogeneic) and Lewis rats (syngeneic).
RESULTS
Without immunosuppression, recipients of chimeric livers experienced acute rejection, and died within 8 to 11 days. With immunosuppression, they all survived for >112 days with normal weight gain compared to syngeneic controls, while all xenogeneic controls died within 98 days due to rejection with Banff scores >6 (p = 0.0014). The chimeric grafts underwent post-transplant remodelling, growing by 670% on average. Rat hepatocytes fully replaced mouse hepatocytes starting from day 56 (absence of detectable mouse serum albumin, histological clearance of mouse hepatocytes). In addition, rat albumin levels reached those of syngeneic recipients. Four months after transplantation of chimeric livers, we observed the development of diffuse mature rat bile ducts through transdifferentiation of hepatocytes (up to 72% of cholangiocytes), and patchy areas of portal endothelium originating from the host (seen in one out of five recipients).
CONCLUSIONS
Taken together, these data demonstrate the efficacy of transplanting rat-to-mouse chimeric livers into rats, with a high potential for post-transplant recipient-oriented graft remodelling. Validation in a large animal model is still needed.
LAY SUMMARY
Chimeric animals are composed of cells from different species. Chimeric animals carrying human tissue have the potential to increase the availability of transplantable organs. We transplanted rat-to-mouse liver grafts into newly weaned rats. The chimeric grafts underwent post-transplant remodelling with rat hepatocytes replacing all mouse hepatocytes within 56 days. In addition, we observed the post-transplant development of diffuse mature rat bile ducts through the transformation of hepatocytes, and patchy areas of portal endothelium originating from the host. These data demonstrate the efficacy of transplanting rat-to-mouse chimeric livers into rats, with a high potential for post-transplant graft remodelling.
Topics: Animals; Chimera; Female; Graft Rejection; Hepatocytes; Immunosuppressive Agents; Liver Transplantation; Male; Mice; Mice, Inbred C57BL; Rats; Rats, Inbred Lew; Rats, Wistar; Transplantation, Heterologous
PubMed: 30031887
DOI: 10.1016/j.jhep.2018.07.008 -
Cell and Tissue Research Feb 2023Systemic sclerosis associated with lung interstitial lung disease (SSc-ILD) is the most common cause of death among patients with SSc. Mesenchymal stem cell (MSCs)...
Systemic sclerosis associated with lung interstitial lung disease (SSc-ILD) is the most common cause of death among patients with SSc. Mesenchymal stem cell (MSCs) transplantations had been treated by SSc patients that showed in the previous case report. The therapeutic mechanisms and effects of MSCs on SSc-ILD are still obscure. In this study, we investigated the therapeutic effects and mechanisms of treatment of BM-MSC derived from C57BL/6 on the topoisomerase I (TOPO I) induced SSc-ILD-like mice model. The mice were immunized with a mixture of recombinant human TOPO I in PBS solution (500 U/mL) and completed Freund's adjuvant [CFA; 1:1 (volume/volume)] twice per week for 9 weeks. On week 10, the mice were sacrificed to analyze the related pathological parameters. Lung and skin pathologies were analyzed using histochemical staining. CD4 T-helper (T) cell differentiation in lung and skin-draining lymph nodes was detected using flow cytometry. Our results revealed that allogeneic and syngeneic MSCs exhibited similar repressive effects on TOPO I-induced IgG1 and IgG2a in the SSc group. After intravascular (IV) treatment with syngeneic or allogeneic MSCs, the dermal thickness and fibrosis dramatically condensed and significantly reduced airway hyperresponsiveness. These findings showed that both allogeneic and syngeneic MSCs have therapeutic potential for SSc-ILD.
Topics: Humans; Animals; Mice; DNA Topoisomerases, Type I; Mice, Inbred C57BL; Fibrosis; Scleroderma, Systemic; Lung Diseases, Interstitial; Lung; Pneumonia; Mesenchymal Stem Cells
PubMed: 36447073
DOI: 10.1007/s00441-022-03716-8 -
International Journal of Molecular... Mar 2021We evaluated the effect of manganese ferrite nanoparticles (MFN) on radiosensitization and immunologic responses using the murine hepatoma cell line Hepa1-6 and the...
We evaluated the effect of manganese ferrite nanoparticles (MFN) on radiosensitization and immunologic responses using the murine hepatoma cell line Hepa1-6 and the syngeneic mouse model. The clonogenic survival of Hepa1-6 cells was increased by hypoxia, while being restricted by ionizing radiation (IR) and/or MFN. Although MFN suppressed HIF-1α under hypoxia, the combination of IR and MFN enhanced apoptosis and DNA damage in Hepa1-6 cells. In the Hepa1-6 syngeneic mouse model, the combination of IR and MFN notably limited the tumor growth compared to the single treatment with IR or MFN, and also triggered more frequent apoptosis in tumor tissues than that observed under other conditions. Increased expression of PD-L1 after IR was not observed with MFN alone or the combination of IR and MFN in vitro and in vivo, and the percentage of tumor-infiltrating T cells and cytotoxic T cells increased with MFN, regardless of IR, in the Hepa1-6 syngeneic mouse model, while IR alone led to T cell depletion. MFN might have the potential to overcome radioresistance by alleviating hypoxia and strengthening antitumor immunity in the tumor microenvironment.
Topics: Animals; Carcinoma, Hepatocellular; Cell Line, Tumor; Ferric Compounds; Liver Neoplasms; Lymphocytes, Tumor-Infiltrating; Manganese Compounds; Mice; Nanoparticles; Radiation, Ionizing; Radiation-Sensitizing Agents; T-Lymphocytes; Tumor Microenvironment
PubMed: 33807943
DOI: 10.3390/ijms22052637 -
Journal of Hepatology Aug 2016Human liver chimeric mice are useful models of human hepatitis virus infection, including hepatitis B and C virus infections. Independently, immunodeficient mice...
BACKGROUND & AIMS
Human liver chimeric mice are useful models of human hepatitis virus infection, including hepatitis B and C virus infections. Independently, immunodeficient mice reconstituted with CD34(+) hematopoietic stem cells (HSC) derived from fetal liver reliably develop human T and B lymphocytes. Combining these systems has long been hampered by inefficient liver reconstitution of human fetal hepatoblasts. Our study aimed to enhance hepatoblast engraftment in order to create a mouse model with syngeneic human liver and immune cells.
METHODS
The effects of human oncostatin-M administration on fetal hepatoblast engraftment into immunodeficient fah(-/-) mice was tested. Mice were then transplanted with syngeneic human hepatoblasts and HSC after which human leukocyte chimerism and functionality were analyzed by flow cytometry, and mice were challenged with HBV.
RESULTS
Addition of human oncostatin-M enhanced human hepatoblast engraftment in immunodeficient fah(-/-) mice by 5-100 fold. In contrast to mice singly engrafted with HSC, which predominantly developed human T and B lymphocytes, mice co-transplanted with syngeneic hepatoblasts also contained physiological levels of human monocytes and natural killer cells. Upon infection with HBV, these mice displayed rapid and sustained viremia.
CONCLUSIONS
Our study provides a new mouse model with improved human fetal hepatoblast engraftment and an expanded human immune cell repertoire. With further improvements, this model may become useful for studying human immunity against viral hepatitis.
LAY SUMMARY
Important human pathogens such as hepatitis B virus, hepatitis C virus and human immunodeficiency virus only infect human cells which complicates the development of mouse models for the study of these pathogens. One way to make mice permissive for human pathogens is the transplantation of human cells into immune-compromised mice. For instance, the transplantation of human liver cells will allow the infection of these so-called "liver chimeric mice" with hepatitis B virus and hepatitis C virus. The co-transplantation of human immune cells into liver chimeric mice will further allow the study of human immune responses to hepatitis B virus or hepatitis C virus. However, for immunological studies it will be crucial that the transplanted human liver and immune cells are derived from the same human donor. In our study we describe the efficient engraftment of human fetal liver cells and immune cells derived from the same donor into mice. We show that liver co-engraftment resulted in an expanded human immune cell repertoire, including monocytes and natural killer cells in the liver. We further demonstrate that these mice could be infected with hepatitis B virus, which lead to an expansion of natural killer cells. In conclusion we have developed a new mouse model that could be useful to study human immune responses to human liver pathogens.
Topics: Animals; Hepatitis B; Hepatocytes; Humans; Killer Cells, Natural; Mice; Mice, SCID; Monocytes
PubMed: 27151182
DOI: 10.1016/j.jhep.2016.04.022 -
Otolaryngology--head and Neck Surgery :... Jan 2024Decellularized tracheal grafts possess the biological cues necessary for tissue regeneration. However, conventional decellularization approaches to target the removal of...
OBJECTIVE
Decellularized tracheal grafts possess the biological cues necessary for tissue regeneration. However, conventional decellularization approaches to target the removal of all cell populations including chondrocytes lead to a loss of mechanical support. We have created a partially decellularized tracheal graft (PDTG) that preserves donor chondrocytes and the mechanical properties of the trachea. In this study, we measured PDTG chondrocyte retention with a murine microsurgical model.
STUDY DESIGN
Murine in vivo time-point study.
SETTING
Research Institute affiliated with Tertiary Pediatric Hospital.
METHODS
PDTG was created using a sodium dodecyl sulfate protocol. Partially decellularized and syngeneic grafts were orthotopically implanted into female C57BL/6J mice. Grafts were recovered at 1, 3, and 6 months postimplant. Pre- and postimplant grafts were processed and analyzed via quantitative immunofluorescence. Chondrocytes (SOX9+, DAPI+) present in the host and graft cartilage was evaluated using ImageJ.
RESULTS
Partial decellularization resulted in the maintenance of gross tracheal architecture with the removal of epithelial and submucosal structures on histology. All grafts demonstrated SOX9+ chondrocytes throughout the study time points. Chondrocytes in PDTG were lower at 6 months compared to preimplant and syngeneic controls.
CONCLUSION
PDTG retained donor graft chondrocytes at all time points. However, PDTG exhibits a reduction in chondrocytes at 6 months. The impact of these histologic changes on cartilage extracellular matrix regeneration and repair remains unclear.
Topics: Humans; Child; Female; Mice; Animals; Chondrocytes; Trachea; Tissue Engineering; Mice, Inbred C57BL; Cartilage; Tissue Scaffolds
PubMed: 37365963
DOI: 10.1002/ohn.409 -
Neurosurgical Focus Feb 2022Glioblastoma is the most common primary malignant brain neoplasm with dismal 10-year survival rates of < 1%. Despite promising preliminary results from several novel...
Glioblastoma is the most common primary malignant brain neoplasm with dismal 10-year survival rates of < 1%. Despite promising preliminary results from several novel therapeutic agents, clinical responses have been modest due to several factors, including tumor heterogeneity, immunosuppressive tumor microenvironment, and treatment resistance. Novel immunotherapeutics have been developed to reverse tumor-induced immunosuppression in patients with glioblastomas. In order to recapitulate the tumor microenvironment, reliable in vivo syngeneic murine models are critical for the development of new targeted agents as these models demonstrate rapid tumor induction and reliable tumor growth over multiple generations. Despite the clear advantages of murine models, choosing an appropriate model from an immunological perspective can be difficult and have significant ramifications on the translatability of the results from murine to human trials. Herein, the authors reviewed the 4 most commonly used immunocompetent syngeneic murine glioma models (GL261 [C57BL/6], SB28 [C57BL/6], CT-2A [C57BL/6], and SMA-560 [VM/Dk]) and compared their strengths and weaknesses from an immunological standpoint.
Topics: Animals; Brain Neoplasms; Cell Line, Tumor; Glioblastoma; Glioma; Humans; Immunotherapy; Mice; Mice, Inbred C57BL; Tumor Microenvironment
PubMed: 35104794
DOI: 10.3171/2021.11.FOCUS21556 -
Transplantation Apr 2018Candidates for vascularized composite allotransplantation (VCA) are frequently sensitized, putting them at risk for antibody-mediated rejection. Current desensitization...
BACKGROUND
Candidates for vascularized composite allotransplantation (VCA) are frequently sensitized, putting them at risk for antibody-mediated rejection. Current desensitization strategies are imperfect and require a living-donor setting. Here we investigated the impact of sensitization on and the efficacy of a desensitization protocol utilizing syngeneic hematopoietic stem cell transplantation (HSCT) to prevent antibody-mediated rejection in VCA.
METHODS
Skin transplants from Dark Agouti to Lewis rats were performed for sensitization. Orthotopic hind limb transplants from Dark Agouti donors were performed to sensitized and nonsensitized recipients, and the animals were treated with either daily tacrolimus or no immunosuppression. A desensitization protocol consisting of total body irradiation, fludarabine, and syngeneic HSCT was applied to sensitized animals. Graft rejection was monitored by clinical assessment and histological analysis. Serum levels of donor-specific antibodies (DSA IgG) were measured using flow cytometry.
RESULTS
Sensitized recipients exhibited accelerated rejection by 5.5 ± 1.2 days without immunosuppression and 10.2 ± 3.6 days with daily tacrolimus compared with 8.7 ± 1.2 days and longer than 30 days in nonsensitized recipients, respectively. Serum levels of DSA IgG were markedly elevated (37.3 ± 3.34-fold from baseline) in sensitized recipients after VCA and correlated with histologic evidence of rejection and C4d deposition. Desensitization significantly reduced DSA compared with sensitized controls (2.6 ± 0.5-fold vs 6.0 ± 1.2-fold, P < 0.01) and along with daily tacrolimus led to improved VCA survival longer than 30 days without evidence of C4d deposition (n = 6).
CONCLUSIONS
In summary, sensitization leads to accelerated rejection of VCA, and syngeneic HSCT combined with conventional immunosuppression effectively reduces DSA and improves allograft survival in sensitized rats.
Topics: Animals; Complement C4b; Composite Tissue Allografts; Desensitization, Immunologic; Graft Rejection; Graft Survival; Hematopoietic Stem Cell Transplantation; Hindlimb; Immunosuppressive Agents; Isoantibodies; Male; Models, Animal; Myeloablative Agonists; Peptide Fragments; Rats, Inbred Lew; Skin Transplantation; Tacrolimus; Time Factors; Transplantation, Isogeneic; Vascularized Composite Allotransplantation; Vidarabine
PubMed: 29298238
DOI: 10.1097/TP.0000000000002070