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Background: Hemorrhagic shock is well documented as a leading cause of preventable fatalities among military casualties. During military operations plasma can be transfused while waiting for whole blood. This study was conducted to assess the safety and efficacy of two new freeze‐dried plasma formulations in a porcine model of traumatic hemorrhagic shock. Study Design and Methods: In the face of species‐specific transfusion, transfusible blood products were derived from porcine sources. The efficacy of three lyophilized plasma (LP) formulations was evaluated: lyophilized plasma (LP), concentrated lyophilized plasma (CLP), and platelet‐rich concentrated lyophilized plasma (PCLP). Pigs were subjected to multi‐trauma and hemorrhagic shock. Ninety minutes post‐shock induction, the animals were treated with one of the three lyophilized products. Monitoring included systolic blood pressure and cardiac output. Point‐of‐care and laboratory diagnostic tests were used to assess renal function, real‐time hemostasis (ROTEM), and coagulation. Histological examinations of kidney, lung, and muscle tissues were conducted 4 h after shock induction. Results: CLP and PCLP significantly improved systolic blood pressure and cardiac output and positively influenced base excess, creatinine, various ROTEM, and coagulation markers compared with standard LP without histologic modification. No adverse effect was associated with the transfusion of any of the plasma products throughout the experimental procedures. Conclusion: Both CLP and PCLP exhibit promising therapeutic potential for managing hemorrhagic shock in scenario where whole blood supplies are limited. However, the distinct physiological and coagulation characteristics of the swine model necessitate further investigation using humanized preclinical models to fully understand their clinical applicability and constraints. [ABSTRACT FROM AUTHOR]

Perinatal sources of mesenchymal stromal cells (MSCs) have raised growing interest because they are readily and widely available with minimal ethical/legal issues and can easily be stored for allogeneic settings. In addition, perinatal tissues are known to be important in mediating the fetomaternal tolerance of pregnancy, which confer upon perinatal-MSCs (P-MSCs) a particular interest in immunomodulation. It has been recently shown that it is possible to deeply modify the secreted factor profiles of MSCs with different cytokine stimuli such as interferon gamma or tumor necrosis factor alpha to license MSCs for a better immunosuppresive potential. Therefore, we aimed to compare adult bone marrow-MSCs with MSCs from perinatal tissues (cord blood, umbilical cord, amnion, and chorion) on their in vitro immunological and stromacytic efficiencies under different priming conditions. Our results showed that P-MSCs had a potential to modulate the in vitro immune response and be useful for hematopoietic progenitor cell ex vivo expansion. However, we showed contrasted effects of cytokine priming embedded in an important between-donor variability. In conclusion, our study highlights the importance to elaborate predicitive in vitro tests to screen between-donor variability of perinatal tissues for banking allogeneic standardized MSCs. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are multipotent cells that can be obtained from several sources such as bone marrow and adipose tissue. Depending on the culture conditions, they can differentiate into osteoblasts, chondroblasts, adipocytes, or neurons. In this regard, they constitute promising candidates for cell-based therapy aimed at repairing damaged tissues. In addition, MSCs display immunomodulatory properties through the expression of soluble factors including HLA-G. We here analyse both immunogenicity and immunosuppressive capacity of MSCs derived from bone marrow and adipose tissue before and after osteodifferentiation. Results show that HLA-G expression is maintained after osteodifferentiation and can be boosted in inflammatory conditions mimicked by the addition of IFN-γ and TNF-α. Both MSCs and osteodifferentiated MSCs are hypoimmunogenic and exert immunomodulatory properties in HLA-mismatched settings as they suppress T cell alloproliferation in mixed lymphocyte reactions. Finally, addition of biomaterials that stimulate bone tissue formation did not modify MSC immune properties. As MSCs combine both abilities of osteoregeneration and immunomodulation, they may be considered as allogenic sources for the treatment of bone defects. [ABSTRACT FROM AUTHOR]

Exposure to blast is one of the major causes of death and disability in recent military conflicts. Therefore, it is crucial to evaluate the protective capability of the ballistic-proof equipment worn by soldiers against the effects of blast overpressure (i.e., primary blast injuries). A focus will be made on thoracic protective equipment (TPE). An anthropomorphic mannequin, called BOPMAN, and anesthetized swine both wearing soft, hard or no ballistic protection, were subjected to an open-field high-intensity blast. For swine, thoracic wall motion (acceleration and velocity) was recorded during blast exposure and severity of lung injury was evaluated postmortem. Different data were collected from BOPMAN thoracic responses, including reflected and internal pressure, as well as the force at the rear face of the instrumented part. The severity of blast-induced lung injuries (contusion extent, Axelsson Severity Scale) and the thoracic wall motion were decreased in animals protected with thoracic ceramic hard plates as compared to those wearing soft or no protection. There was a clear trend towards greater lung injury in animals protected with the soft body armor used, even when compared to unprotected animals. In line with these experimental data, the measured force as well as the force impulse measured using BOPMAN were also decreased with a ceramic hard plate protection and increased when a soft ballistic pack was used compared to no protection. Comparison of data collected on BOPMAN and swine equipped with the same protection level revealed that those two force parameters were well correlated with the level of blast-induced lung injury (force, R 2 = 0.74 and force impulse, R 2 = 0.77, p < 0.05). Taken together, our results suggest that the force and the force impulse data from BOPMAN may help estimate the efficiency of existing TPE regarding lung protection under blast exposure and may represent an important tool for development of future TPE., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Boutillier, Cardona, Magnan, Ogier, De Mezzo, Montespan, Menini, Mosnier, Naz and Prat.)