Background: Recently, growing evidence has indicated an important role of the complement system, a crucial component of immunity, in mediating neuroinflammation and promoting neuronal apoptosis following closed head injury (CHI). We previously reported that transplanted induced neural stem cells (iNSCs) pre-treated with CHI mouse serum could enhance complement receptor type 1-related protein y (Crry) expression and ameliorate complement-mediated damage in mouse CHI models. However, the mechanism underlying the elevated levels of Crry expression remains elusive.
Methods: CHI models were established using a standardized weight-drop device. We collected CHI mouse serum at 12 h post-trauma. RT-QPCR assay, western blot analysis, complement deposition assay, Akt inhibition assay, flow cytometry, cell transplantation, and functional assay were utilized to clarify the mechanism of Crry expression in iNSCs receiving CHI mouse serum treatment.
Results: We observed dramatic increases in the levels of Crry expression and Akt activation in iNSCs receiving CHI mouse serum treatment. Remarkably, Akt inhibition led to the reduction of Crry expression in iNSCs. Intriguingly, the treatment of iNSC-derived neurons with recombinant complement receptor 2-conjugated Crry (CR2-Crry), which inhibits all complement pathways, substantially enhanced Crry expression and Akt activation in neurons after CHI mouse serum treatment. In subsequent in vitro experiments of pre-treatment of iNSCs with CR2-Crry, we observed significant increases in the levels of Crry expression and Akt activation in iNSCs and iNSC-derived astrocytes and neurons post-treatment with CHI mouse serum. Additionally, an in vivo study showed that intracerebral-transplanted iNSCs pre-treated with CR2-Crry markedly enhanced Crry expression in neurons and protected neurons from complement-dependent damage in the brains of CHI mice.
Conclusion: INSCs receiving CR2-Crry pre-treatment increased the levels of Crry expression in iNSCs and iNSC-derived astrocytes and neurons and attenuated complement-mediated injury following CHI.
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http://dx.doi.org/10.1186/s13287-021-02186-z | DOI Listing |
Neural Regen Res
May 2025
Department of Neurosurgery, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China.
JOURNAL/nrgr/04.03/01300535-202505000-00025/figure1/v/2024-07-28T173839Z/r/image-tiff Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair. We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling, influencing their activation such that they can promote neurological recovery.
View Article and Find Full Text PDFJCI Insight
May 2024
Division of Nephrology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
Stem Cell Reports
February 2024
Department of Immunobiology, University of Arizona College of Medicine, Tucson, AZ 85724, USA; Department of Surgery, University of Arizona College of Medicine, Tucson, AZ 85724, USA; BIO5 Institute, University of Arizona, Tucson, AZ 85724, USA. Electronic address:
Successful allogeneic human pluripotent stem cell (hPSC)-derived therapies must overcome immunological rejection by the recipient. To build reagents to define these barriers, we genetically ablated β2M, TAP1, CIITA, CD74, MICA, and MICB to limit expression of HLA-I, HLA-II, and natural killer (NK) cell activating ligands in hPSCs. Transplantation of these cells that also expressed covalent single chain trimers of Qa1 and H2-K to inhibit NK cells and CD55, Crry, and CD59 to inhibit complement deposition led to persistent teratomas in wild-type mice.
View Article and Find Full Text PDFJ Neuroimmunol
December 2023
Neuroimmunology, Stress, and Endocrinology (NISE) Laboratory, University of Ottawa, Ottawa, ON K1N 6N5, Canada; LIFE Research Institute, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada. Electronic address:
CD46 is a complementary regulatory protein ubiquitously expressed in human cells, controlling complement system activation. CD46 has further been identified to have several other functions including regulatory T cell induction and intestinal epithelial (IEC) barrier regulation. Activation of CD46 in the IEC can impact intestinal barrier permeability and immune system functioning.
View Article and Find Full Text PDFJ Neuroinflammation
October 2023
Rheumatology and Rare Disease Research Center, The Wohl Institute for Translational Medicine, Hadassah-Hebrew University Medical Center and School of Medicine, Jerusalem, Israel.
Background: Homozygous CD59-deficient patients manifest with recurrent peripheral neuropathy resembling Guillain-Barré syndrome (GBS), hemolytic anemia and recurrent strokes. Variable mutations in CD59 leading to loss of function have been described and, overall, 17/18 of patients with any mutation presented with recurrent GBS. Here we determine the localization and possible role of membrane-bound complement regulators, including CD59, in the peripheral nervous systems (PNS) of mice and humans.
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