About this Research Topic
Before and after cloning of the BST-1 gene, several monoclonal antibodies were made, recognizing identical molecules to human and murine BST-1, which revealed that multiple cell-lineages expressed BST-1 including bone marrow stromal cells derived from rheumatoid arthritis, mesenchymal stem cells and myeloid cells in humans. In murine systems, BST-1 is expressed by pro-B and Pro-T cells, mature myeloid cells, a subpopulation of reticular cells in lymphoid tissues, and endothelial stem cells.
One important function of BST-1 is supporting hematopoietic cells spanning from stem cells to effector cells through the metabolic regulation of micro-environments or niches by supplying enzymatic products. In this context, immune regulatory roles for BST-1 on fibroblastic reticular cells and follicular dendritic cells may be still overlooked or not completely understood.
The secondary function of BST-1 as a receptor to transduce signals was identified in early studies showing that cross-linking of BST-1 on human monocytic cell lines induced tyrosine- phosphorylation. Additionally, Ligation of BST-1 on human neutrophils inhibited migration. Mechanisms for this function is partly explained by the binding ability of BST-1 to extracellular matrix proteins, such as fibronectin, and physical association with CD11b/CD18 complexes. Moreover, in defense against Mycobacterium tuberculosis, BST-1 in macrophages facilitates the interaction of TLR2 with PKCz and ROS production. Increases of a soluble form of BST-1 are detected in rheumatoid arthritis, malignant mesothelioma, and tuberculosis, and its pathophysiological effects by regulating microenvironments or interfering with the receptor function are suggested. On mesenchymal stem cells, binding of a newly identified ligand, SCRG1 to BST-1 transduces signals to regulate migration and maintain stemness.
Thirdly, BST-1 is a protective role against psychotic behaviors; depression and anxiety. More recently, it has been shown that SNPs in BST1 locus are novel risk factors for Parkinson's disease, linking the immune system with the nervous system.
This Research Topic intends to provide a comprehensive overview of the immunological functions of a multi-talented ectoenzyme, BST-1. We welcome authors to submit Original Research and Review articles focusing on, but not limited to, the following subtopics:
1. Mechanistic studies of BST-1 in immune-competent cells, including B, and myeloid cells and stroma-like cells in microenvironments.
2. Role of BST-1 in immune-related diseases
3. Role of BST-1 in bridging the immune system to other systems (nervous, metabolic, digestive, urogenital and reproductive)
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