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Stroke is the most common cerebrovascular disease, the second leading cause of death behind heart disease and is a major cause of long-term disability worldwide. Currently, systemic immunomodulatory therapy based on intravenous cells is attracting attention. The immune response to acute stroke is a major factor in cerebral ischaemia (CI) pathobiology and outcomes. Over the past decade, the significant contribution of the spleen to ischaemic stroke has gained considerable attention in stroke research. The changes in the spleen after stroke are mainly reflected in morphology, immune cells and cytokines, and these changes are closely related to the stroke outcomes. Autonomic nervous system (ANS) activation, release of central nervous system (CNS) antigens and chemokine/chemokine receptor interactions have been documented to be essential for efficient brain-spleen cross-talk after stroke. In various experimental models, human umbilical cord blood cells (hUCBs), haematopoietic stem cells (HSCs), bone marrow stem cells (BMSCs), human amnion epithelial cells (hAECs), neural stem cells (NSCs) and multipotent adult progenitor cells (MAPCs) have been shown to reduce the neurological damage caused by stroke. The different effects of these cell types on the interleukin (IL)-10, interferon (IFN), and cholinergic anti-inflammatory pathways in the spleen after stroke may promote the development of new cell therapy targets and strategies. The spleen will become a potential target of various stem cell therapies for stroke represented by MAPC treatment. [ABSTRACT FROM AUTHOR]

Background: Protein C receptor (Procr) has recently been shown to mark resident adult stem cells in the mammary gland, vascular system, and pancreatic islets. More so, high Procr expression was also detected and used as indicator for subsets of triple-negative breast cancers (TNBCs). Previous study has revealed Procr as a target of Wnt/β-catenin signaling; however, direct upstream regulatory mechanism of Procr remains unknown. To comprehend the molecular role of Procr during physiology and pathology, elucidating the upstream effectors of Procr is necessary. Here, we provide a system for screening negative regulators of Procr, which could be adapted for broad molecular analysis on membrane proteins., Results: We established a screening system which combines CRISPR-Cas9 guided gene disruption with fluorescence activated cell sorting technique (FACS). CommaDβ (murine epithelial cells line) was used for the initial Procr upstream effector screening using lentiviral CRISPR-gRNA library. Shortlisted genes were further validated through individual lentiviral gRNA infection followed by Procr expression evaluation. Adam17 was identified as a specific negative inhibitor of Procr expression. In addition, MDA-MB-231 cells and Hs578T cells (human breast cancer cell lines) were used to verify the conserved regulation of ADAM17 over PROCR expression., Conclusion: We established an efficient CRISPR-Cas9/FACS screening system, which identifies the regulators of membrane proteins. Through this system, we identified Adam17 as the negative regulator of Procr membrane expression both in mammary epithelial cells and breast cancer cells., (© 2021. The Author(s).)

Background: β 7 integrins are responsible for the efficient recruitment of lymphocytes from the blood and their retention in gut-associated lymphoid tissues. Integrin α 4 β 7 binds MAdCAM-1, mediating rolling adhesion of lymphocytes on blood vessel walls when inactive and firm adhesion when activated, thereby controlling two critical steps of lymphocyte homing to the gut. By contrast, integrin α E β 7 mediates the adhesion of lymphocytes to gut epithelial cells by interacting with E-cadherin. Integrin β 7 blocking antibodies have shown efficacy in clinical management of inflammatory bowel disease (IBD); however, fully blocking β 7 function leads to the depletion of colonic regulatory T (Treg) cells and exacerbates dextran sulfate sodium (DSS)-induced colitis by evoking aberrant innate immunity, implying its potential adverse effect for IBD management. Thus, a better therapeutic strategy targeting integrin β 7 is required to avoid this adverse effect., Results: Herein, we inhibited integrin α 4 β 7 activation in vivo by creating mice that carry in their integrin β 7 gene a mutation (F185A) which from structural studies is known to lock α 4 β 7 in its resting state. Lymphocytes from β 7 -F185A knock-in (KI) mice expressed α 4 β 7 integrins that could not be activated by chemokines and showed significantly impaired homing to the gut. The β 7 -F185A mutation did not inhibit α E β 7 activation, but led to the depletion of α E β 7 + lymphocytes in the spleen and a significantly reduced population of α E β 7 + lymphocytes in the gut of KI mice. β 7 -F185A KI mice were resistant to T cell transfer-induced chronic colitis, but did not show an increased susceptibility to DSS-induced innate colitis, the adverse effect of fully blocking β 7 function., Conclusions: Our findings demonstrate that specific inhibition of integrin α 4 β 7 activation is a potentially better strategy than fully blocking α 4 β 7 function for IBD treatment.

Background: The clinical presentation of common symptoms during depressive episodes in bipolar disorder (BD) and major depressive disorder (MDD) poses challenges for accurate diagnosis. Disorder-specific neuroanatomical features may aid the development of reliable discrimination between these two clinical conditions., Methods: For our sample of 16 BD patients, 19 MDD patients and 29 healthy volunteers, we adopted vertex-wise cortical based brain imaging techniques to examine cortical thickness and surface area, two components of cortical volume with distinct genetic determinants. Based on specific characteristics of neuroanatomical features, we then used support vector machine (SVM) algorithm to discriminate between patients with BD and MDD., Results: Compared to MDD patients, BD patients showed significantly larger cortical surface area in the left bankssts, precuneus, precentral, inferior parietal, superior parietal and the right middle temporal gyri. In addition, larger volumes of subcortical regions were found in BD patients. In SVM discriminative analyses, the overall accuracy was 74.3 %, with a sensitivity of 62.5 % and a specificity of 84.2 % (p = 0.028). Compared to controls, larger surface area in the temporo-parietal regions were observed in BD patients, and thinner cortices in fronto-temporal regions were observed in MDD patients, especially in the medial orbito-frontal area., Conclusions: These findings have demonstrated distinct spatially distributed variations in cortical thickness and surface area in patients with BD and MDD, suggesting potentially varying etiological and neuropathological processes in these two conditions. The employment of multimodal classification on disorder-specific biological features has shed light to the development of potential classification tools that could aid diagnostic decisions.

Background: Accumulating evidence suggests that neuroinflammation plays an important role in the progression of Parkinson's disease (PD). Excessively activated microglia produce several pro-inflammatory enzymes and pro-inflammatory cytokines, leading to damage to surrounding neurons and eventually inducing neurodegeneration. Therefore, the inhibition of microglial overactivation may be a potential therapeutic strategy to prevent the further progression of PD. β-Hydroxybutyric acid (BHBA) has been shown to suppress lipopolysaccharide (LPS)-induced inflammation in BV-2 cells and to protect dopaminergic neurons in previous studies, but the underlying mechanisms remain unclear. Thus, in this study, we further investigated this mechanism in LPS-induced in vivo and in vitro PD models., Methods: For the in vitro experiments, primary mesencephalic neuron-glia cultures were pretreated with BHBA and stimulated with LPS. [(3)H]dopamine (DA) uptake, tyrosine hydroxylase-immunoreactive (TH-ir) neurons and morphological analysis were evaluated and analyzed in primary mesencephalic neuron-glia cultures. In vivo, microglial activation and the injury of dopaminergic neurons were induced by LPS intranigral injection, and the effects of BHBA treatment on microglial activation and the survival ratio and function of dopaminergic neurons were investigated. Four our in vitro mechanistic experiment, primary microglial cells were pretreated with BHBA and stimulated with LPS; the cells were then assessed for the responses of pro-inflammatory enzymes and pro-inflammatory cytokines, and the NF-κB signaling pathway was evaluated and analyzed., Results: We found that BHBA concentration-dependently attenuated the LPS-induced decrease in [(3)H]DA uptake and loss of TH-ir neurons in the primary mesencephalic neuron/glia mixed culture. BHBA treatment significantly improved the motor dysfunction of the PD model rats induced by intranigral injection of LPS, and this beneficial effect of BHBA was attributed to the inhibition of microglial overactivation and the protection of dopaminergic neurons in the substantia nigra (SN). Our in vitro mechanistic study revealed that the inhibitory effect of BHBA on microglia was mediated by G-protein-coupled receptor 109A (GPR109A) and involved the NF-κB signaling pathway, causing the inhibition of pro-inflammatory enzyme (iNOS and COX-2) and pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) production., Conclusions: In conclusion, the present study supports the effectiveness of BHBA in protecting dopaminergic neurons against inflammatory challenge.