Cell Therapies for Acute Radiation Syndrome.

The risks of severe ionizing radiation exposure are increasing due to the involvement of nuclear powers in combat operations, the increasing use of nuclear power, and the existence of terrorist threats. Exposure to a whole-body radiation dose above about 0.7 Gy results in H-ARS (hematopoietic acute radiation syndrome), which is characterized by damage to the hematopoietic system; higher doses result in further damage to the gastrointestinal and nervous systems.

Short-term assays for mesenchymal stromal cell immunosuppression of T-lymphocytes.

Introduction: Trauma patients are susceptible to coagulopathy and dysfunctional immune responses. Mesenchymal stromal cells (MSCs) are at the forefront of the cellular therapy revolution with profound immunomodulatory, regenerative, and therapeutic potential. Routine assays to assess immunomodulation activity examine MSC effects on proliferation of peripheral blood mononuclear cells (PBMCs) and take 3-7 days.

Refrigerated human mesenchymal stromal cells as an alternative to cryostorage for use in clinical investigation.

Background: Mesenchymal stromal cells (MSCs) and other therapeutic cells show efficacy for cardiac damage, neurological disease, chronic lung disease, pediatric graft versus host disease, and several inflammatory conditions. Based on their anti-inflammatory and immune-modulatory activities, responsiveness, and secretion of beneficial factors, cellular therapeutics may provide benefits in acute and chronic traumatic injury. However, the use of live cells presents logistical challenges, especially for military trauma.

Metabolic effects of radiation on red blood cells from cold stored whole blood.

Background: The risk of military and civilian radiation exposure is increasing, and determining the effects of exposure is a high priority. Irradiation of the nearby blood supply after a nuclear event may impede mobilization of blood products for resuscitation at a time of great need. RBCs are administered to patients with trauma and hemorrhage to transport and deliver oxygen and avoid tissue hypoxia.

Effects of radiation exposure and storage on the energy metabolome of platelets in whole blood.

Background: Exposure to radiation through battlefield use of nuclear weapons, terrorist attacks or accidents at nuclear power plants is a current concern for the military. Beyond the risk of exposure to personnel is the intentional or accidental irradiation of our blood banking supply system. It is unknown how large doses of ionizing radiation affect storage of blood and blood products, including platelets.

High-dose radiation exposure of cold-stored whole blood does not affect hemostatic function.

Background: Whole blood (WB) transfusion is routinely used to resuscitate severely injured military trauma patients. Blood can be stored refrigerated while still maintaining reasonable function but is susceptible to environmental influences, including radiation exposure. Immune-compromised patients are transfused with irradiated blood to inactivate donor lymphocyte function (25 Gy per Association for the Advancement of Blood and Biotherapies [AARB] standard 5.

Intravenous administration of mesenchymal stromal cells leads to a dose-dependent coagulopathy and is unable to attenuate acute traumatic coagulopathy in rats.

Background: Mesenchymal stromal cells (MSCs) express surface tissue factor (TF), which may affect hemostasis and detract from therapeutic outcomes of MSCs if administered intravenously. In this study, we determine a safe dose of MSCs for intravenous (IV) administration and further demonstrate the impact of IV-MSC on acute traumatic coagulopathy (ATC) in rats.

Methods: Tissue factor expression of rat bone marrow-derived mesenchymal stromal cell (BMSC) or adipose-derived mesenchymal stromal cell (AMSC) was detected by immunohistochemistry and enzyme-linked immunosorbent assay.

Interactions of human mesenchymal stromal cells with peripheral blood mononuclear cells in a Mitogenic proliferation assay.

Background: Immunomodulation by mesenchymal stromal cells (MSCs) is a potentially important therapeutic modality. MSCs suppress peripheral blood mononuclear cell (PBMC) proliferation in vitro, suggesting a mechanism for suppressing inflammatory responses in vivo. This study details the interactions of PBMCs and MSCs.

Neglected No More: Emerging Cellular Therapies in Traumatic Injury.

Traumatic injuries are a leading cause of death and disability in both military and civilian populations. Given the complexity and diversity of traumatic injuries, novel and individualized treatment strategies are required to optimize outcomes. Cellular therapies have potential benefit for the treatment of acute or chronic injuries, and various cell-based pharmaceuticals are currently being tested in preclinical studies or in clinical trials.

A streamlined proliferation assay using mixed lymphocytes for evaluation of human mesenchymal stem cell immunomodulation activity.

Background: Mesenchymal stromal cells (MSCs) have been proposed for treatment of acute respiratory distress syndrome (ARDS), graft versus host disease (GVHD), wound healing and trauma. A consensus is building that immunomodulation by MSCs is important for therapeutic potential. MSCs suppress peripheral blood mononuclear cell (PBMC) proliferation in vitro, potentially reflecting an ability to suppress PBMC inflammatory responses in vivo.

Use of multiple potency assays to evaluate human mesenchymal stromal cells.

Background: There is broad interest in the use of cell therapies and cell products for treatment of a variety of diseases and problems. Of interest to the military, cellular therapies have the potential to confer tremendous benefit for treatment of both acute and chronic injuries. Although many different cell therapy products are currently under investigation, mesenchymal stromal cells (MSCs) are good candidates, based on their ability to respond to inflammation, limit vascular permeability, and modulate immune responses to injury.

Human mesenchymal stromal cell source and culture conditions influence extracellular vesicle angiogenic and metabolic effects on human endothelial cells in vitro.

Background: Mesenchymal stem/stromal cell (MSC)-derived extracellular vesicles (EVs) are a possible cell-free alternative to MSCs because they retain the regenerative potential of MSCs, while still mitigating some of their limitations (such as the possible elicitation of host immune responses). The promotion and restoration of angiogenesis, however, is an important component in treating trauma-related injuries, and has not been fully explored with EVs. Herein, we describe the effects of monolayer adipose-derived EVs, spheroid adipose-derived EVs (SAd-EVs), monolayer bone marrow-derived EVs (MBM-EVs), and spheroid bone marrow-derived EVs (SBM-EVs) on human umbilical vein endothelial cell (HUVEC) tube formation and mitochondrial respiration.

Human primary fibroblasts perform similarly to MSCs in assays used to evaluate MSC safety and potency.

Background: Cellular therapeutic agents may benefit trauma patients by modulating the immune response to injury, and by reducing inflammation and vascular leakage. Administration of allogeneic mesenchymal stromal cells (MSCs) shows some benefit in preclinical and clinical trials, but less testing has been performed with other cell types. Human primary fibroblasts (FBs) were compared to MSCs in assays designed to evaluate MSCs to determine if these assays actually evaluate properties unique to MSCs or whether related cell types perform similarly.

Tissue Source and Cell Expansion Condition Influence Phenotypic Changes of Adipose-Derived Stem Cells.

Stem cells derived from the subcutaneous adipose tissue of debrided burned skin represent an appealing source of adipose-derived stem cells (ASCs) for regenerative medicine. Traditional tissue culture uses fetal bovine serum (FBS), which complicates utilization of ASCs in human medicine. Human platelet lysate (hPL) is one potential xeno-free, alternative supplement for use in ASC culture.

Procoagulant activity of human mesenchymal stem cells.

Background: Allogeneic mesenchymal stem cells (MSCs) show great potential for the treatment of military and civilian trauma based on their reduced immunogenicity and ability to modulate inflammation and immune function in the recipient. Although generally considered to be safe, MSCs express tissue factor (TF), a potent activator of coagulation. In the current study, we evaluated multiple MSC populations for tissue factor expression and procoagulant activity to characterize safety considerations for systemic use of MSCs in trauma patients who may have altered coagulation homeostasis.

Adaptations to chronic rapamycin in mice.

Rapamycin inhibits mechanistic (or mammalian) target of rapamycin (mTOR) that promotes protein production in cells by facilitating ribosome biogenesis (RiBi) and eIF4E-mediated 5'cap mRNA translation. Chronic treatment with encapsulated rapamycin (eRapa) extended health and life span for wild-type and cancer-prone mice. Yet, the long-term consequences of chronic eRapa treatment are not known at the organ level.

p53 and rapamycin are additive.

Mechanistic target of rapamycin (mTOR) is a kinase found in a complex (mTORC1) that enables macromolecular synthesis and cell growth and is implicated in cancer etiology. The rapamycin-FK506 binding protein 12 (FKBP12) complex allosterically inhibits mTORC1. In response to stress, p53 inhibits mTORC1 through a separate pathway involving cell signaling and amino acid sensing.

p53 as an intervention target for cancer and aging.

p53 is well known for suppressing tumors but could also affect other aging processes not associated with tumor suppression. As a transcription factor, p53 responds to a variety of stresses to either induce apoptosis (cell death) or cell cycle arrest (cell preservation) to suppress tumor development. Yet, the effect p53 has on the non-cancer aspects of aging is complicated and not well understood.

SULT2B1b sulfotransferase: induction by vitamin D receptor and reduced expression in prostate cancer.

An elevated tumor tissue androgen level, which reactivates androgen receptor in recurrent prostate cancer, arises from the intratumor synthesis of 5α-dihydrotestosterone through use of the precursor steroid dehydroepiandrosterone (DHEA) and is fueled by the steroidogenic enzymes 3β-hydroxysteroid dehydrogenase (3β-HSD1), aldoketoreductase (AKR1C3), and steroid 5-alpha reductase, type 1 (SRD5A1) present in cancer tissue. Sulfotransferase 2B1b (SULT2B1b) (in short, SULT2B) is a prostate-expressed hydroxysteroid SULT that converts cholesterol, oxysterols, and DHEA to 3β-sulfates. DHEA metabolism involving sulfonation by SULT2B can potentially interfere with intraprostate androgen synthesis due to reduction of free DHEA pool and, thus, conversion of DHEA to androstenedione.

Rapamycin extends life span of Rb1+/- mice by inhibiting neuroendocrine tumors.

Chronic treatment of mice with an enterically released formulation of rapamycin (eRapa) extends median and maximum life span, partly by attenuating cancer. The mechanistic basis of this response is not known. To gain a better understanding of thesein vivo effects, we used a defined preclinical model of neuroendocrine cancer, Rb1+/- mice.

Ubiquitin-dependent degradation of Id1 and Id3 is mediated by the COP9 signalosome.

Recently, evidence is accumulating pointing to a function of the COP9 signalosome (CSN) in regulation of ubiquitination by specific ubiquitin ligases. Here, we demonstrate by mammalian two-hybrid analysis that the transcriptional regulators and substrates of the ubiquitin system Id1 and Id3, but not Id2 and Id4, bind to the CSN subunit CSN5. Pull-down experiments revealed that Id3 physically interacts with the CSN complex.

STAT6 mediates interleukin-4 growth inhibition in human breast cancer cells.

In addition to acting as a hematopoietic growth factor, interleukin-4 (IL-4) inhibits growth of some transformed cells in vitro and in vivo. In this study, we show that insulin receptor substrate (IRS)-1, IRS-2, and signal transducer and activator of transcription 6 (STAT6) are phosphorylated following IL-4 treatment in MCF-7 breast cancer cells. STAT6 DNA binding is enhanced by IL-4 treatment.