The Experts below are selected from a list of 8727 Experts worldwide ranked by ideXlab platform
Dale L Greiner - One of the best experts on this subject based on the ideXlab platform.
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abstract 5632 pbmc Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy
Immunology, 2020Co-Authors: Danying Cai, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, Jing Jiao, Hongyuan Yang, Mingshan Cheng, James G KeckAbstract:Immunotherapeutic antibodies and cell therapies have proven to be highly effective cancer therapy for solid tumors, leukemia and lymphomas. The immunotherapy acts in part by stimulating and redirecting the immune system to attack cancer cells, and cytokines can be released during the process. As a consequence cytokine release syndrome (CRS) is a common adverse effect caused by immunotherapy which could be very severe in patients. The animal models and in vitro human PBMC assays presently in use unfortunately can9t reliably predict the CRS in patients. To address the gap between pre-clinical testing and clinical trials we have developed a rapid, sensitive and reproducible Humanized Mouse model for quantitating CRS. Immunodeficient NSG™ mice were irradiated and injected with human PBMCs intravenously. In general PBMC-engrafted mice had 10-20% human immune cells (hCD45+) in blood with ~70% of the hCD45+ cells being CD3+ T cells and ~20% being CD56+ NK cells. PBMC-engrafted mice were used for treatment within 6 days. We demonstrated that a number of human cytokines including IFN-γ, IL-2, IL-4, IL-6, IL-10 and TNF-α were elevated in blood in the Humanized mice treated with monoclonal antibodies and bispecifics including anti-CD3, anti-CD28, anti-PD-1 and BiTE molecules. The cytokine release was dependent on the dose and time of treatment, and PBMCs from every human donor tested were capable of responding to produce cytokines. Notably the amount of cytokines produced varied from donor to donor in >40 different PBMCs tested so far and cytokine levels of >10-fold difference were frequently observed, indicating that the animal model could reveal individual differences in human donors. As a result human donors could be divided into three types as high, medium or low responders. PBMC-engrafted mice implanted with tumors could also be used. Tumor-bearing PBMC-Humanized model would be required to evaluate molecules such as BiTE since CRS activity was most evident when both targets for BiTE molecules were present during the assay. PBMC-engrafted NSG™ mice were used for CRS assessment prior to the development of acute graft-vs-host disease (GVHD) in all of the experiments. We were able to reproduce the data using a NSG™ strain [NSG-(Kb Db)null (IAnull)] doubly deficient in murine MHC class I and II molecules, or double knockout (KO) mice. The double KO mice are known to engraft human PBMCs in a manner very similar to NSG™ and have a significantly delayed onset of GVHD [Brehm et al., FASEB J. 33, 3137 (2019)]. Results from the double KO mice further validated cytokine release was not GvHD related and the NSG™ mice is a robust model for CRS assessment of immunotherapy in vivo. We have described a PBMC-Humanized model using NSG™ mice that offers rapid assessment of potential risks of therapeutic agents in causing CRS in vivo. The model could differentiate individual human differences based on the cytokine release. Citation Format: Danying Cai, Jing Jiao, Chunting Ye, Hongyuan Yang, Mingshan Cheng, Michael A. Brehm, Dale L. Greiner, Leonard D. Shultz, James G. Keck. PBMC-Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5632.
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abstract 4990 an in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing pbmc Humanized mice
Cancer Research, 2019Co-Authors: Mingshan Cheng, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, James G KeckAbstract:Monoclonal antibodies (mAbs), as either single agents or in combination, have shown remarkable efficacy for cancer immunotherapy. However the use of antibody-based immunotherapies can result in the development of severe adverse effects for many patients, including cytokine release syndrome (CRS). Two methodologies used routinely for CRS drug toxicity testing are in vitro assays with human PBMC and in vivo testing in animal models. Unfortunately, neither method reliably predicts the immune toxicity in humans. For example, in vitro testing does not mimic the complexities of the biological environment in humans, and testing of human-specific agents in either rodent or non-human primates is limited by the many species-specific differences in immune system function. This significant gap between pre-clinical testing of novel therapeutics and clinical trials demonstrates a critical need for translational protocols that more accurately predict immune toxicity. We have developed a novel Humanized Mouse model for testing CRS that is rapid, sensitive and reproducible. This model is based on human PBMC engraftment of NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG; JAX stock number 005557) mice, and assessment of CRS is performed within 6 days of PBMC injection. Within 6 days of PBMC injection, total human immune cell (CD45+) levels averaged 10 to 15% of cells in blood with approximately 70% and 25% of the human CD45+ cells being CD3+ T cells or CD56+ NK cells, respectively. To validate this model, PBMC-engrafted NSG mice were challenged with OKT3 (anti-CD3) by day 6 after PBMC injection, which is a timepoint prior to the development of robust xenogeneic GVHD. Severe clinical symptoms developed rapidly in OKT3-treated mice, including production of human cytokines and a significant drop in body temperature as compared to control PBS-treated mice. Using our validated Humanized Mouse model, induction of CRS was tested using clinically relevant mAb as either single agents, including pembrolizumab, anti-CD28, and ATG (anti-thymocyte globulin). We observed robust clinical readouts for these mAb treatments, with induction of rapid and distinct cytokine release profiles. Moreover our assay also identified donors that were “high” responders and “low” responders to specific mAb treatments. A direct comparison of our Humanized Mouse model to an in vitro based PBMC assay revealed several advantages for the Humanized assay, including higher sensitivity and more accurate recapitulation of clinical observations. Notably our Humanized Mouse model also demonstrated utility when evaluating combination therapies, including pembrolizumab/lenalidomide, pembrolizumab/ATG, and anti-CD28/ATG and enabled the identification of unique patterns of CRS. In conclusion, we have developed a translational Humanized Mouse model for preclinical assessment of CRS adverse events to mAb therapeutics. Citation Format: Chunting Ye, Mingshan Cheng, Michael Brehm, Dale Greiner, Leonard Shultz, James G. Keck. An in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing PBMC Humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4990.
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Humanized Mouse models of immunological diseases and precision medicine
Mammalian Genome, 2019Co-Authors: Leonard D. Shultz, Dale L Greiner, James Keck, Lisa Burzenski, Sonal Jangalwe, Shantashri Vaidya, Michael A BrehmAbstract:With the increase in knowledge resulting from the sequencing of the human genome, the genetic basis for the underlying differences in individuals, their diseases, and how they respond to therapies is starting to be understood. This has formed the foundation for the era of precision medicine in many human diseases that is beginning to be implemented in the clinic, particularly in cancer. However, preclinical testing of therapeutic approaches based on individual biology will need to be validated in animal models prior to translation into patients. Although animal models, particularly murine models, have provided significant information on the basic biology underlying immune responses in various diseases and the response to therapy, murine and human immune systems differ markedly. These fundamental differences may be the underlying reason why many of the positive therapeutic responses observed in mice have not translated directly into the clinic. There is a critical need for preclinical animal models in which human immune responses can be investigated. For this, many investigators are using Humanized mice, i.e., immunodeficient mice engrafted with functional human cells, tissues, and immune systems. We will briefly review the history of Humanized mice, the remaining limitations, approaches to overcome them and how Humanized Mouse models are being used as a preclinical bridge in precision medicine for evaluation of human therapies prior to their implementation in the clinic.
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development of a Humanized Mouse model that recapitulates the fibrotic response to biomaterial implants
Journal of Immunology, 2017Co-Authors: Atieh Sadraei, Joshua C Doloff, Rita Bortell, Michael A Brehm, Dale L Greiner, Shady Farah, Dustin Anderson, Robert LangerAbstract:Implanted biomedical devices reside within tens of millions of patients in the United States alone, and are involved in millions of new surgeries every year. They comprise a major component of modern medicine and are essential for many clinical applications ranging from hip/knee replacement, tissue repair/reconstruction, controlled release, sensing, and cell transplantation. Limiting therapeutic performance and lifespan, immune-mediated foreign body rejection results in sequestration behind dense layers of fibrotic scar tissue. Current approaches for management of long-term biomedical device implantation often involve broad-spectrum anti-inflammatories. However, these agents are not specific to individual immune populations, and have side effects in vivo . To avoid such issues, improved biomaterials need to be identified with reduced immunogenicity. Deeper understanding of immune-mediated foreign body responses was leveraged to generate a variant of the Humanized Mouse model, previously unreported in the field of host rejection of biomaterial implants, that is capable of recapitulating fibrosis. Here, we present this model in comparison to wildtype systems, including rodents and non-human primates. Cellular and cytokine responses were determined with numerous biomaterials—hydrogel alginate, ceramic glass, and polymer polystyrene, across multiple implant sites. This model allows us to investigate human immune cells interacting directly with implantables, without putting patients at risk. It is our hope this model can be used as a pre-clinical diagnostic tool for screening implantable synthetic as well as natural materials for immunogenicity.
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Humanized Mouse models of clinical disease
Annual Review of Pathology-mechanisms of Disease, 2017Co-Authors: Nicole C Walsh, Michael A Brehm, Dale L Greiner, Laurie L. Kenney, Sonal Jangalwe, Kenedwin Aryee, Leonard D. ShultzAbstract:Immunodeficient mice engrafted with functional human cells and tissues, that is, Humanized mice, have become increasingly important as small, preclinical animal models for the study of human diseases. Since the description of immunodeficient mice bearing mutations in the IL2 receptor common gamma chain (IL2rgnull) in the early 2000s, investigators have been able to engraft murine recipients with human hematopoietic stem cells that develop into functional human immune systems. These mice can also be engrafted with human tissues such as islets, liver, skin, and most solid and hematologic cancers. Humanized mice are permitting significant progress in studies of human infectious disease, cancer, regenerative medicine, graft-versus-host disease, allergies, and immunity. Ultimately, use of Humanized mice may lead to the implementation of truly personalized medicine in the clinic. This review discusses recent progress in the development and use of Humanized mice and highlights their utility for the study of human diseases.
Leonard D. Shultz - One of the best experts on this subject based on the ideXlab platform.
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abstract 5632 pbmc Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy
Immunology, 2020Co-Authors: Danying Cai, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, Jing Jiao, Hongyuan Yang, Mingshan Cheng, James G KeckAbstract:Immunotherapeutic antibodies and cell therapies have proven to be highly effective cancer therapy for solid tumors, leukemia and lymphomas. The immunotherapy acts in part by stimulating and redirecting the immune system to attack cancer cells, and cytokines can be released during the process. As a consequence cytokine release syndrome (CRS) is a common adverse effect caused by immunotherapy which could be very severe in patients. The animal models and in vitro human PBMC assays presently in use unfortunately can9t reliably predict the CRS in patients. To address the gap between pre-clinical testing and clinical trials we have developed a rapid, sensitive and reproducible Humanized Mouse model for quantitating CRS. Immunodeficient NSG™ mice were irradiated and injected with human PBMCs intravenously. In general PBMC-engrafted mice had 10-20% human immune cells (hCD45+) in blood with ~70% of the hCD45+ cells being CD3+ T cells and ~20% being CD56+ NK cells. PBMC-engrafted mice were used for treatment within 6 days. We demonstrated that a number of human cytokines including IFN-γ, IL-2, IL-4, IL-6, IL-10 and TNF-α were elevated in blood in the Humanized mice treated with monoclonal antibodies and bispecifics including anti-CD3, anti-CD28, anti-PD-1 and BiTE molecules. The cytokine release was dependent on the dose and time of treatment, and PBMCs from every human donor tested were capable of responding to produce cytokines. Notably the amount of cytokines produced varied from donor to donor in >40 different PBMCs tested so far and cytokine levels of >10-fold difference were frequently observed, indicating that the animal model could reveal individual differences in human donors. As a result human donors could be divided into three types as high, medium or low responders. PBMC-engrafted mice implanted with tumors could also be used. Tumor-bearing PBMC-Humanized model would be required to evaluate molecules such as BiTE since CRS activity was most evident when both targets for BiTE molecules were present during the assay. PBMC-engrafted NSG™ mice were used for CRS assessment prior to the development of acute graft-vs-host disease (GVHD) in all of the experiments. We were able to reproduce the data using a NSG™ strain [NSG-(Kb Db)null (IAnull)] doubly deficient in murine MHC class I and II molecules, or double knockout (KO) mice. The double KO mice are known to engraft human PBMCs in a manner very similar to NSG™ and have a significantly delayed onset of GVHD [Brehm et al., FASEB J. 33, 3137 (2019)]. Results from the double KO mice further validated cytokine release was not GvHD related and the NSG™ mice is a robust model for CRS assessment of immunotherapy in vivo. We have described a PBMC-Humanized model using NSG™ mice that offers rapid assessment of potential risks of therapeutic agents in causing CRS in vivo. The model could differentiate individual human differences based on the cytokine release. Citation Format: Danying Cai, Jing Jiao, Chunting Ye, Hongyuan Yang, Mingshan Cheng, Michael A. Brehm, Dale L. Greiner, Leonard D. Shultz, James G. Keck. PBMC-Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5632.
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abstract 4990 an in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing pbmc Humanized mice
Cancer Research, 2019Co-Authors: Mingshan Cheng, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, James G KeckAbstract:Monoclonal antibodies (mAbs), as either single agents or in combination, have shown remarkable efficacy for cancer immunotherapy. However the use of antibody-based immunotherapies can result in the development of severe adverse effects for many patients, including cytokine release syndrome (CRS). Two methodologies used routinely for CRS drug toxicity testing are in vitro assays with human PBMC and in vivo testing in animal models. Unfortunately, neither method reliably predicts the immune toxicity in humans. For example, in vitro testing does not mimic the complexities of the biological environment in humans, and testing of human-specific agents in either rodent or non-human primates is limited by the many species-specific differences in immune system function. This significant gap between pre-clinical testing of novel therapeutics and clinical trials demonstrates a critical need for translational protocols that more accurately predict immune toxicity. We have developed a novel Humanized Mouse model for testing CRS that is rapid, sensitive and reproducible. This model is based on human PBMC engraftment of NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG; JAX stock number 005557) mice, and assessment of CRS is performed within 6 days of PBMC injection. Within 6 days of PBMC injection, total human immune cell (CD45+) levels averaged 10 to 15% of cells in blood with approximately 70% and 25% of the human CD45+ cells being CD3+ T cells or CD56+ NK cells, respectively. To validate this model, PBMC-engrafted NSG mice were challenged with OKT3 (anti-CD3) by day 6 after PBMC injection, which is a timepoint prior to the development of robust xenogeneic GVHD. Severe clinical symptoms developed rapidly in OKT3-treated mice, including production of human cytokines and a significant drop in body temperature as compared to control PBS-treated mice. Using our validated Humanized Mouse model, induction of CRS was tested using clinically relevant mAb as either single agents, including pembrolizumab, anti-CD28, and ATG (anti-thymocyte globulin). We observed robust clinical readouts for these mAb treatments, with induction of rapid and distinct cytokine release profiles. Moreover our assay also identified donors that were “high” responders and “low” responders to specific mAb treatments. A direct comparison of our Humanized Mouse model to an in vitro based PBMC assay revealed several advantages for the Humanized assay, including higher sensitivity and more accurate recapitulation of clinical observations. Notably our Humanized Mouse model also demonstrated utility when evaluating combination therapies, including pembrolizumab/lenalidomide, pembrolizumab/ATG, and anti-CD28/ATG and enabled the identification of unique patterns of CRS. In conclusion, we have developed a translational Humanized Mouse model for preclinical assessment of CRS adverse events to mAb therapeutics. Citation Format: Chunting Ye, Mingshan Cheng, Michael Brehm, Dale Greiner, Leonard Shultz, James G. Keck. An in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing PBMC Humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4990.
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Humanized Mouse models of immunological diseases and precision medicine
Mammalian Genome, 2019Co-Authors: Leonard D. Shultz, Dale L Greiner, James Keck, Lisa Burzenski, Sonal Jangalwe, Shantashri Vaidya, Michael A BrehmAbstract:With the increase in knowledge resulting from the sequencing of the human genome, the genetic basis for the underlying differences in individuals, their diseases, and how they respond to therapies is starting to be understood. This has formed the foundation for the era of precision medicine in many human diseases that is beginning to be implemented in the clinic, particularly in cancer. However, preclinical testing of therapeutic approaches based on individual biology will need to be validated in animal models prior to translation into patients. Although animal models, particularly murine models, have provided significant information on the basic biology underlying immune responses in various diseases and the response to therapy, murine and human immune systems differ markedly. These fundamental differences may be the underlying reason why many of the positive therapeutic responses observed in mice have not translated directly into the clinic. There is a critical need for preclinical animal models in which human immune responses can be investigated. For this, many investigators are using Humanized mice, i.e., immunodeficient mice engrafted with functional human cells, tissues, and immune systems. We will briefly review the history of Humanized mice, the remaining limitations, approaches to overcome them and how Humanized Mouse models are being used as a preclinical bridge in precision medicine for evaluation of human therapies prior to their implementation in the clinic.
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Humanized Mouse models of clinical disease
Annual Review of Pathology-mechanisms of Disease, 2017Co-Authors: Nicole C Walsh, Michael A Brehm, Dale L Greiner, Laurie L. Kenney, Sonal Jangalwe, Kenedwin Aryee, Leonard D. ShultzAbstract:Immunodeficient mice engrafted with functional human cells and tissues, that is, Humanized mice, have become increasingly important as small, preclinical animal models for the study of human diseases. Since the description of immunodeficient mice bearing mutations in the IL2 receptor common gamma chain (IL2rgnull) in the early 2000s, investigators have been able to engraft murine recipients with human hematopoietic stem cells that develop into functional human immune systems. These mice can also be engrafted with human tissues such as islets, liver, skin, and most solid and hematologic cancers. Humanized mice are permitting significant progress in studies of human infectious disease, cancer, regenerative medicine, graft-versus-host disease, allergies, and immunity. Ultimately, use of Humanized mice may lead to the implementation of truly personalized medicine in the clinic. This review discusses recent progress in the development and use of Humanized mice and highlights their utility for the study of human diseases.
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Humanized Mouse model of mast cell mediated passive cutaneous anaphylaxis and passive systemic anaphylaxis
The Journal of Allergy and Clinical Immunology, 2016Co-Authors: Paul J. Bryce, Leonard D. Shultz, Laurie L. Kenney, Rustom Falahati, John Leung, Christopher Bebbington, Nenad Tomasevic, Rebecca Krier, Chia Lin Hsu, Dale L GreinerAbstract:Background Mast cells are a critical component of allergic responses in humans, and animal models that allow the in vivo investigation of their contribution to allergy and evaluation of new human-specific therapeutics are urgently needed. Objective To develop a new Humanized Mouse model that supports human mast cell engraftment and human IgE-dependent allergic responses. Methods This model is based on the NOD- scid IL2rg null SCF/GM-CSF/IL3 (NSG-SGM3) strain of mice engrafted with human thymus, liver, and hematopoietic stem cells (termed Bone marrow, Liver, Thymus [BLT]). Results Large numbers of human mast cells develop in NSG-SGM3 BLT mice and populate the immune system, peritoneal cavity, and peripheral tissues. The human mast cells in NSG-SGM3 BLT mice are phenotypically similar to primary human mast cells and express CD117, tryptase, and FceRI. These mast cells undergo degranulation in an IgE-dependent and -independent manner, and can be readily cultured in vitro for additional studies. Intradermal priming of engrafted NSG-SGM3 mice with a chimeric IgE containing human constant regions resulted in the development of a robust passive cutaneous anaphylaxis response. Moreover, we describe the first report of a human mast cell antigen-dependent passive systemic anaphylaxis response in primed mice. Conclusions NSG-SGM3 BLT mice provide a readily available source of human mast cells for investigation of mast cell biology and a preclinical model of passive cutaneous anaphylaxis and passive systemic anaphylaxis that can be used to investigate the pathogenesis of human allergic responses and to test new therapeutics before their advancement to the clinic.
Ramesh Akkina - One of the best experts on this subject based on the ideXlab platform.
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zika viral infection and neutralizing human antibody response in a blt Humanized Mouse model
Virology, 2018Co-Authors: Kimberly Schmitt, Paige Charlins, Milena Veselinovic, Lauren Kinnerbibeau, Shuang Hu, James Curlin, Leila Remlingmulder, Ken E Olson, Tawfik A Aboellail, Ramesh AkkinaAbstract:Abstract Many murine and non-human primate animal models have been recently developed to understand Zika viral pathogenesis. However, a major limitation with these models is the inability to directly examine the human-specific immune response. Here, we utilized a BLT Humanized Mouse model endowed with a transplanted human immune system. Plasma viremia could be detected within 48 h after viral challenge and viremia persisted for as long as 220 days in some mice. Neutralizing human antibody was detected in infected mice and Mouse sera showed reactivity with the viral envelope and capsid proteins in a radio-immunoprecipitation assay. Human monocytes/macrophages, B cells and hematopoietic stem cells in the bone marrow were found to be virus infected. These data establish that BLT mice are permissive for Zika viral infection and are capable of generating viral-specific human immune responses thus providing a human surrogate model for future testing of vaccine and antiviral therapeutic candidates.
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improvements and limitations of Humanized Mouse models for hiv research nih niaid meet the experts 2015 workshop summary
AIDS Research and Human Retroviruses, 2016Co-Authors: Ramesh Akkina, Atef Allam, Alejandro B Balazs, Joel N Blankson, John C Burnett, Sofia Casares, Victor J Garcia, Kim J Hasenkrug, Fatah Kashanchi, Scott G KitchenAbstract:The number of Humanized Mouse models for the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and other infectious diseases has expanded rapidly over the past 8 years. Highly immunodeficient Mouse strains, such as NOD/SCID/gamma chain(null) (NSG, NOG), support better human hematopoietic cell engraftment. Another improvement is the derivation of highly immunodeficient mice, transgenic with human leukocyte antigens (HLAs) and cytokines that supported development of HLA-restricted human T cells and heightened human myeloid cell engraftment. Humanized mice are also used to study the HIV reservoir using new imaging techniques. Despite these advances, there are still limitations in HIV immune responses and deficits in lymphoid structures in these models in addition to xenogeneic graft-versus-host responses. To understand and disseminate the improvements and limitations of Humanized Mouse models to the scientific community, the NIH sponsored and convened a meeting on April 15, 2015 to discuss the state of knowledge concerning these questions and best practices for selecting a Humanized Mouse model for a particular scientific investigation. This report summarizes the findings of the NIH meeting.
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hiv pre exposure prophylaxis mucosal tissue drug distribution of rt inhibitor tenofovir and entry inhibitor maraviroc in a Humanized Mouse model
Virology, 2014Co-Authors: Milena Veselinovic, Leila Remlingmulder, Kuo Hsiung Yang, Jonathan Lecureux, Craig Sykes, Angela D M Kashuba, Ramesh AkkinaAbstract:Abstract Pre-exposure prophylaxis (PrEP) strategies utilizing anti-retroviral drugs show considerable promise for HIV prevention. However there is insufficient pharmacokinetic (PK) data on drug concentrations required for protection at the relevant mucosal tissues where the infection is initiated. Here we evaluated the utility of a Humanized Mouse model to derive PK data on two leading drugs, the RT inhibitor Tenofovir (TFV) and CCR5 inhibitor Maraviroc (MVC). Following oral dosing, both the drugs and the intracellular active TFV-diphosphate could be detected in vaginal, rectal and intestinal tissues. The drug exposures (AUC24 h) were found to be higher in vaginal tissue compared to plasma with even higher levels detected in rectal and intestinal tissues. The overall trends of drug concentrations seen in Humanized mice reflect those seen in the human thus establishing the utility of this model complementing the present non-human primate (NHP) models for future pre-clinical evaluations of promising HIV PrEP drug candidates.
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oral pre exposure prophylaxis by anti retrovirals raltegravir and maraviroc protects against hiv 1 vaginal transmission in a Humanized Mouse model
PLOS ONE, 2010Co-Authors: Preston C Neff, Thomas Ndolo, Apurva Tandon, Yuichiro Habu, Ramesh AkkinaAbstract:Sexual HIV-1 transmission by vaginal route is the most predominant mode of viral transmission, resulting in millions of new infections every year. In the absence of an effective vaccine, there is an urgent need to develop other alternative methods of pre-exposure prophylaxis (PrEP). Many novel drugs that are currently approved for clinical use also show great potential to prevent viral sexual transmission when administered systemically. A small animal model that permits rapid preclinical evaluation of potential candidates for their systemic PrEP efficacy will greatly enhance progress in this area of investigation. We have previously shown that RAG-hu Humanized Mouse model permits HIV-1 mucosal transmission via both vaginal and rectal routes and displays CD4 T cell loss typical to that seen in the human. Thus far systemic PrEP studies have been primarily limited to RT inhibitors exemplified by tenofovir and emtricitabine. In these proof-of-concept studies we evaluated two new classes of clinically approved drugs with different modes of action namely, an integrase inhibitor raltegravir and a CCR5 inhibitor maraviroc as potential systemically administered chemo-prophylactics. Our results showed that oral administration of either of these drugs fully protects against vaginal HIV-1 challenge in the RAG-hu Mouse model. Based on these results both these drugs show great promise for further development as orally administered PrEPs.
Michael A Brehm - One of the best experts on this subject based on the ideXlab platform.
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abstract 5632 pbmc Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy
Immunology, 2020Co-Authors: Danying Cai, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, Jing Jiao, Hongyuan Yang, Mingshan Cheng, James G KeckAbstract:Immunotherapeutic antibodies and cell therapies have proven to be highly effective cancer therapy for solid tumors, leukemia and lymphomas. The immunotherapy acts in part by stimulating and redirecting the immune system to attack cancer cells, and cytokines can be released during the process. As a consequence cytokine release syndrome (CRS) is a common adverse effect caused by immunotherapy which could be very severe in patients. The animal models and in vitro human PBMC assays presently in use unfortunately can9t reliably predict the CRS in patients. To address the gap between pre-clinical testing and clinical trials we have developed a rapid, sensitive and reproducible Humanized Mouse model for quantitating CRS. Immunodeficient NSG™ mice were irradiated and injected with human PBMCs intravenously. In general PBMC-engrafted mice had 10-20% human immune cells (hCD45+) in blood with ~70% of the hCD45+ cells being CD3+ T cells and ~20% being CD56+ NK cells. PBMC-engrafted mice were used for treatment within 6 days. We demonstrated that a number of human cytokines including IFN-γ, IL-2, IL-4, IL-6, IL-10 and TNF-α were elevated in blood in the Humanized mice treated with monoclonal antibodies and bispecifics including anti-CD3, anti-CD28, anti-PD-1 and BiTE molecules. The cytokine release was dependent on the dose and time of treatment, and PBMCs from every human donor tested were capable of responding to produce cytokines. Notably the amount of cytokines produced varied from donor to donor in >40 different PBMCs tested so far and cytokine levels of >10-fold difference were frequently observed, indicating that the animal model could reveal individual differences in human donors. As a result human donors could be divided into three types as high, medium or low responders. PBMC-engrafted mice implanted with tumors could also be used. Tumor-bearing PBMC-Humanized model would be required to evaluate molecules such as BiTE since CRS activity was most evident when both targets for BiTE molecules were present during the assay. PBMC-engrafted NSG™ mice were used for CRS assessment prior to the development of acute graft-vs-host disease (GVHD) in all of the experiments. We were able to reproduce the data using a NSG™ strain [NSG-(Kb Db)null (IAnull)] doubly deficient in murine MHC class I and II molecules, or double knockout (KO) mice. The double KO mice are known to engraft human PBMCs in a manner very similar to NSG™ and have a significantly delayed onset of GVHD [Brehm et al., FASEB J. 33, 3137 (2019)]. Results from the double KO mice further validated cytokine release was not GvHD related and the NSG™ mice is a robust model for CRS assessment of immunotherapy in vivo. We have described a PBMC-Humanized model using NSG™ mice that offers rapid assessment of potential risks of therapeutic agents in causing CRS in vivo. The model could differentiate individual human differences based on the cytokine release. Citation Format: Danying Cai, Jing Jiao, Chunting Ye, Hongyuan Yang, Mingshan Cheng, Michael A. Brehm, Dale L. Greiner, Leonard D. Shultz, James G. Keck. PBMC-Humanized Mouse model for the assessment of cytokine release syndrome caused by checkpoint and bispecific immunotherapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5632.
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abstract 4990 an in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing pbmc Humanized mice
Cancer Research, 2019Co-Authors: Mingshan Cheng, Michael A Brehm, Leonard D. Shultz, Dale L Greiner, James G KeckAbstract:Monoclonal antibodies (mAbs), as either single agents or in combination, have shown remarkable efficacy for cancer immunotherapy. However the use of antibody-based immunotherapies can result in the development of severe adverse effects for many patients, including cytokine release syndrome (CRS). Two methodologies used routinely for CRS drug toxicity testing are in vitro assays with human PBMC and in vivo testing in animal models. Unfortunately, neither method reliably predicts the immune toxicity in humans. For example, in vitro testing does not mimic the complexities of the biological environment in humans, and testing of human-specific agents in either rodent or non-human primates is limited by the many species-specific differences in immune system function. This significant gap between pre-clinical testing of novel therapeutics and clinical trials demonstrates a critical need for translational protocols that more accurately predict immune toxicity. We have developed a novel Humanized Mouse model for testing CRS that is rapid, sensitive and reproducible. This model is based on human PBMC engraftment of NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG; JAX stock number 005557) mice, and assessment of CRS is performed within 6 days of PBMC injection. Within 6 days of PBMC injection, total human immune cell (CD45+) levels averaged 10 to 15% of cells in blood with approximately 70% and 25% of the human CD45+ cells being CD3+ T cells or CD56+ NK cells, respectively. To validate this model, PBMC-engrafted NSG mice were challenged with OKT3 (anti-CD3) by day 6 after PBMC injection, which is a timepoint prior to the development of robust xenogeneic GVHD. Severe clinical symptoms developed rapidly in OKT3-treated mice, including production of human cytokines and a significant drop in body temperature as compared to control PBS-treated mice. Using our validated Humanized Mouse model, induction of CRS was tested using clinically relevant mAb as either single agents, including pembrolizumab, anti-CD28, and ATG (anti-thymocyte globulin). We observed robust clinical readouts for these mAb treatments, with induction of rapid and distinct cytokine release profiles. Moreover our assay also identified donors that were “high” responders and “low” responders to specific mAb treatments. A direct comparison of our Humanized Mouse model to an in vitro based PBMC assay revealed several advantages for the Humanized assay, including higher sensitivity and more accurate recapitulation of clinical observations. Notably our Humanized Mouse model also demonstrated utility when evaluating combination therapies, including pembrolizumab/lenalidomide, pembrolizumab/ATG, and anti-CD28/ATG and enabled the identification of unique patterns of CRS. In conclusion, we have developed a translational Humanized Mouse model for preclinical assessment of CRS adverse events to mAb therapeutics. Citation Format: Chunting Ye, Mingshan Cheng, Michael Brehm, Dale Greiner, Leonard Shultz, James G. Keck. An in vivo method for determining cancer immunotherapy induced cytokine release syndrome utilizing PBMC Humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4990.
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Humanized Mouse models of immunological diseases and precision medicine
Mammalian Genome, 2019Co-Authors: Leonard D. Shultz, Dale L Greiner, James Keck, Lisa Burzenski, Sonal Jangalwe, Shantashri Vaidya, Michael A BrehmAbstract:With the increase in knowledge resulting from the sequencing of the human genome, the genetic basis for the underlying differences in individuals, their diseases, and how they respond to therapies is starting to be understood. This has formed the foundation for the era of precision medicine in many human diseases that is beginning to be implemented in the clinic, particularly in cancer. However, preclinical testing of therapeutic approaches based on individual biology will need to be validated in animal models prior to translation into patients. Although animal models, particularly murine models, have provided significant information on the basic biology underlying immune responses in various diseases and the response to therapy, murine and human immune systems differ markedly. These fundamental differences may be the underlying reason why many of the positive therapeutic responses observed in mice have not translated directly into the clinic. There is a critical need for preclinical animal models in which human immune responses can be investigated. For this, many investigators are using Humanized mice, i.e., immunodeficient mice engrafted with functional human cells, tissues, and immune systems. We will briefly review the history of Humanized mice, the remaining limitations, approaches to overcome them and how Humanized Mouse models are being used as a preclinical bridge in precision medicine for evaluation of human therapies prior to their implementation in the clinic.
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development of a Humanized Mouse model that recapitulates the fibrotic response to biomaterial implants
Journal of Immunology, 2017Co-Authors: Atieh Sadraei, Joshua C Doloff, Rita Bortell, Michael A Brehm, Dale L Greiner, Shady Farah, Dustin Anderson, Robert LangerAbstract:Implanted biomedical devices reside within tens of millions of patients in the United States alone, and are involved in millions of new surgeries every year. They comprise a major component of modern medicine and are essential for many clinical applications ranging from hip/knee replacement, tissue repair/reconstruction, controlled release, sensing, and cell transplantation. Limiting therapeutic performance and lifespan, immune-mediated foreign body rejection results in sequestration behind dense layers of fibrotic scar tissue. Current approaches for management of long-term biomedical device implantation often involve broad-spectrum anti-inflammatories. However, these agents are not specific to individual immune populations, and have side effects in vivo . To avoid such issues, improved biomaterials need to be identified with reduced immunogenicity. Deeper understanding of immune-mediated foreign body responses was leveraged to generate a variant of the Humanized Mouse model, previously unreported in the field of host rejection of biomaterial implants, that is capable of recapitulating fibrosis. Here, we present this model in comparison to wildtype systems, including rodents and non-human primates. Cellular and cytokine responses were determined with numerous biomaterials—hydrogel alginate, ceramic glass, and polymer polystyrene, across multiple implant sites. This model allows us to investigate human immune cells interacting directly with implantables, without putting patients at risk. It is our hope this model can be used as a pre-clinical diagnostic tool for screening implantable synthetic as well as natural materials for immunogenicity.
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Humanized Mouse models of clinical disease
Annual Review of Pathology-mechanisms of Disease, 2017Co-Authors: Nicole C Walsh, Michael A Brehm, Dale L Greiner, Laurie L. Kenney, Sonal Jangalwe, Kenedwin Aryee, Leonard D. ShultzAbstract:Immunodeficient mice engrafted with functional human cells and tissues, that is, Humanized mice, have become increasingly important as small, preclinical animal models for the study of human diseases. Since the description of immunodeficient mice bearing mutations in the IL2 receptor common gamma chain (IL2rgnull) in the early 2000s, investigators have been able to engraft murine recipients with human hematopoietic stem cells that develop into functional human immune systems. These mice can also be engrafted with human tissues such as islets, liver, skin, and most solid and hematologic cancers. Humanized mice are permitting significant progress in studies of human infectious disease, cancer, regenerative medicine, graft-versus-host disease, allergies, and immunity. Ultimately, use of Humanized mice may lead to the implementation of truly personalized medicine in the clinic. This review discusses recent progress in the development and use of Humanized mice and highlights their utility for the study of human diseases.
Alexander Ploss - One of the best experts on this subject based on the ideXlab platform.
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recapitulation of treatment response patterns in a novel Humanized Mouse model for chronic hepatitis b virus infection
Virology, 2017Co-Authors: Benjamin Y Winer, Michael V Wiles, Tiffany Huang, Benjamin E Low, Cindy Avery, Mihaialexandru Pais, Gabriela Hrebikova, Evelyn Siu, Luis Chiriboga, Alexander PlossAbstract:There are ~350 million chronic carriers of hepatitis B (HBV). While a prophylactic vaccine and drug regimens to suppress viremia are available, chronic HBV infection is rarely cured. HBV's limited host tropism leads to a scarcity of susceptible small animal models and is a hurdle to developing curative therapies. Mice that support engraftment with human hepatoctyes have traditionally been generated through crosses of murine liver injury models to immunodeficient backgrounds. Here, we describe the disruption of fumarylacetoacetate hydrolase directly in the NOD Rag1-/- IL2RγNULL (NRG) background using zinc finger nucleases. The resultant human liver chimeric mice sustain persistent HBV viremia for >90 days. When treated with standard of care therapy, HBV DNA levels decrease below detection but rebound when drug suppression is released, mimicking treatment response observed in patients. Our study highlights the utility of directed gene targeting approaches in zygotes to create new Humanized Mouse models for human diseases.
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Humanized mice for modeling human infectious disease challenges progress and outlook
Cell Host & Microbe, 2009Co-Authors: Alexander Ploss, Nicolas Legrand, Rudi Balling, Pablo D Becker, Chiara Borsotti, Nicolas Brezillon, Jennifer DebarryAbstract:Over 800 million people worldwide are infected with hepatitis viruses, human immunodeficiency virus (HIV), and malaria, resulting in more than 5 million deaths annually. Here we discuss the potential and challenges of Humanized Mouse models for developing effective and affordable therapies and vaccines, which are desperately needed to combat these diseases.