As a potential source of organs for xenotransplantation, pigs that are transgenic for human decay accelerating factor (DAF) have been bred in order to overcome hyperacute rejection. We investigated the protective effect of human DAF in a porcine working heart model perfused by human blood. Hearts of normal landrace pits served as controls. The following parameters were measured: stroke work index, coronary flow and arteriovenous oxygen consumption, 6-keto prostaglandin F1alpha and prostaglandin E2 as markers of endothelial cell activation; creatine phosphokinase and lactate dehydrogenase for evaluation of the extent of myocardial damage; TNFalpha and IL-6 as markers of mononuclear cell activation. Histological and ultrastructural investigations from myocardial tissue sections were done at the end of perfusion. Human (h) DAF appeared to inhibit complement-mediated endothelial cell activation of transgenic pig hearts successfully. This was in contrast to landrace pig hearts, which had a sixfold increase of prostaglandin levels during perfusion with human blood. The cardiac weight increase during perfusion time due to interstitial edema tended to be less in the hDAF group. Myocardial damage was minimal in transgenic hearts, whereas normal pig hearts produced a threefold increase of creatine phosphokinase and lactate dehydrogenase levels. In these hearts, electron microscopy revealed single cell necrosis of myocytes and vacuolization of mitochondria with cristae rupture. According to the results obtained in the working heart model, the breeding of pigs that are transgenic for hDAF represents a promising step to making heart xenotransplantation a clinical reality in the future.
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http://dx.doi.org/10.1097/00007890-199609270-00005 | DOI Listing |
Plant Commun
January 2025
Department of Plant Biology, Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, Almas allé 5, 756 51, Uppsala, Sweden. Electronic address:
Plants possess remarkable regenerative abilities to form de novo vasculature after damage and in response to pathogens that invade and withdraw nutrients. To look for common factors that affect vascular formation upon stress, we searched for Arabidopsis thaliana genes differentially expressed upon Agrobacterium infection, nematode infection and plant grafting. One such gene was cell wall related and highly induced by all three stresses and was named ENHANCED XYLEM AND GRAFTING1 (EXG1) since mutations in it promoted ectopic xylem formation in Vascular cell Induction culture System Using Arabidopsis Leaves (VISUAL) and enhanced graft formation.
View Article and Find Full Text PDFTurk J Haematol
January 2025
Tianjin Medical University General Hospital, Department of Hematology, Tianjin, P. R. China.
Objective: Immune-related pancytopenia (IRP) is characterized by autoantibody-mediated destruction or suppression of bone marrow cells, leading to pancytopenia. This study aimed to explore the role of TRAPPC4 (trafficking protein particle complex subunit 4) as a key autoantigen in IRP, including epitope identification and immune activation mechanisms.
Methods: A total of 90 participants were included in the study, divided into four groups: 30 newly diagnosed IRP patients, 25 IRP remission patients, 20 patients with control hematologic conditions (severe aplastic anemia [SAA] and myelodysplastic syndrome [MDS]), and 15 healthy controls.
Blood Rev
January 2025
Department of Hematology, First Hospital of Jilin University, Changchun, Jilin, China. Electronic address:
Multiple myeloma (MM) remains incurable and patients eventually face the relapse/refractory dilemma. B cell maturation antigen (BCMA)-targeted immunotherapeutic approaches have shown great effectiveness in patients with relapsed/refractory MM, mainly including chimeric antigen receptor T cells (CAR-T), bispecific T cell engagers (TCEs), and antibody-drug conjugates (ADCs). However, their impact on long-term survival remains to be determined.
View Article and Find Full Text PDFJ Dermatol Sci
December 2024
Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan; Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan. Electronic address:
Background: Altered Fli1 expression is associated with various autoimmune diseases, yet its impact on B cells remains unexplored.
Objective: This study investigated the direct effects of Fli1 depletion on B cell populations, focusing on age-associated B cells (ABCs).
Methods: Splenocytes of Fli1 BcKO (Cd19-Cre; Fli1) and Cd19-Cre mice were analyzed flow cytometrically.
J Dermatol Sci
January 2025
Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan; Department of Frontier Science and Interdisciplinary Research, Faculty of Medicine, Kanazawa University, Ishikawa, Japan. Electronic address:
Background: Melanocytes protect the body from ultraviolet radiation by synthesizing melanin. Tyrosinase, a key enzyme in melanin production, accumulates in the endoplasmic reticulum (ER) during melanin synthesis, potentially causing ER stress. However, regulating ER function for melanin synthesis has been less studied than controlling Tyrosinase activity.
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