Retinitis pigmentosa (RP) is an inherited blinding disease characterized by progressive loss of retinal photoreceptors. There are numerous rodent models of retinal degeneration, but most are poor platforms for interventions that will translate into clinical practice. The rabbit possesses a number of desirable qualities for a model of retinal disease including a large eye and an existing and substantial knowledge base in retinal circuitry, anatomy, and ophthalmology. We have analyzed degeneration, remodeling, and reprogramming in a rabbit model of retinal degeneration, expressing a rhodopsin proline 347 to leucine transgene in a TgP347L rabbit as a powerful model to study the pathophysiology and treatment of retinal degeneration. We show that disease progression in the TgP347L rabbit closely tracks human cone-sparing RP, including the cone-associated preservation of bipolar cell signaling and triggering of reprogramming. The relatively fast disease progression makes the TgP347L rabbit an excellent model for gene therapy, cell biological intervention, progenitor cell transplantation, surgical interventions, and bionic prosthetic studies.

Hemorrhagic transformation (HT) is a feared complication of cerebral ischemic infarction, especially following the use of thrombolytic therapy. In this study, we examined whether docosahexaenoic acid (DHA; 22:6n-3), an omega-3 essential fatty acid family member, can protect the brain from injury and whether DHA can decrease the risk of HT enhanced by hyperglycemia after focal ischemic injury. Male Sprague-Dawley rats were injected with 50% dextrose (6ml/kg intraperitoneally) to induce hyperglycemia 10min before 1.5h of filament middle cerebral artery occlusion (MCAO) was performed. Treatment with DHA (10mg/kg) 5min before reperfusion reduced HT and further improved the 7-day neurological outcome. It also reduced infarct volume, which is consistent with the restricted DWI and T2WI hyperintensive area. Reduced Evans Blue extravasation and increased expression of collagen IV indicated the improved integrity of the blood-brain barrier (BBB) in DHA-treated rats. Moreover, DHA reduced the expression of the intercellular adhesion molecule-1 (ICAM-1) in the ischemic injured brain. Therefore, we conclude that DHA attenuated hyperglycemia-enhanced HT and improved neurological function by preserving the integrity of BBB and reducing inflammation.

Tuberculosis (TB) vaccine development has focused largely on targeting T helper type 1 (Th1) cells. However, despite inducing Th1 cells, the recombinant TB vaccine MVA85A failed to enhance protection against TB disease in humans. In recent years, Th17 cells have emerged as key players in vaccine-induced protection against TB. However, the exact cytokine and immune requirements that enable Th17-induced recall protection remain unclear. In this study, we have investigated the requirements for Th17 cell-induced recall protection against Mycobacterium tuberculosis (Mtb) challenge by utilizing a tractable adoptive transfer model in mice. We demonstrate that adoptive transfer of Mtb-specific Th17 cells into naive hosts, and upon Mtb challenge, results in Th17 recall responses that confer protection at levels similar to vaccination strategies. Importantly, although interleukin (IL)-23 is critical, IL-12 and IL-21 are dispensable for protective Th17 recall responses. Unexpectedly, we demonstrate that interferon-γ (IFN-γ) produced by adoptively transferred Th17 cells impairs long-lasting protective recall immunity against Mtb challenge. In contrast, CXCR5 expression is crucial for localization of Th17 cells near macrophages within well-formed B-cell follicles to mediate Mtb control. Thus, our data identify new immune characteristics that can be harnessed to improve Th17 recall responses for enhancing vaccine design against TB.

Apoptosis has essential roles in a variety of cellular and developmental processes. Although the pathway is well studied, how the activities of individual components in the pathway are regulated is less understood. In Drosophila, a key component in apoptosis is Drosophila inhibitor of apoptosis protein 1 (DIAP1), which is required to prevent caspase activation. Here, we demonstrate that Drosophila CG42593 (ubr3), encoding the homolog of mammalian UBR3, has an essential role in regulating the apoptosis pathway. We show that loss of ubr3 activity causes caspase-dependent apoptosis in Drosophila eye and wing discs. Our genetic epistasis analyses show that the apoptosis induced by loss of ubr3 can be suppressed by loss of initiator caspase Drosophila Nedd2-like caspase (Dronc), or by ectopic expression of the apoptosis inhibitor p35, but cannot be rescued by overexpression of DIAP1. Importantly, we show that the activity of Ubr3 in the apoptosis pathway is not dependent on its Ring-domain, which is required for its E3 ligase activity. Furthermore, we find that through the UBR-box domain, Ubr3 physically interacts with the neo-epitope of DIAP1 that is exposed after caspase-mediated cleavage. This interaction promotes the recruitment and ubiquitination of substrate caspases by DIAP1. Together, our data indicate that Ubr3 interacts with DIAP1 and positively regulates DIAP1 activity, possibly by maintaining its active conformation in the apoptosis pathway.

CD44, a transmembrane glycoprotein expressed in a variety of cells and tissues, has been implicated in tumour metastasis. But the molecular mechanisms of CD44-mediated tumour cell metastasis remain to be elucidated.

Killing cancer cells through the induction of apoptosis is one of the main mechanisms of chemotherapy. However, numerous cancer cells have primary or acquired apoptosis resistance, resulting in chemoresistance. In this study, using a novel chalcone derivative chalcone-24 (Chal-24), we identified a novel anticancer mechanism through autophagy-mediated necroptosis (RIP1- and RIP3-dependent necrosis). Chal-24 potently killed different cancer cells with induction of necrotic cellular morphology while causing no detectable caspase activation. Blocking the necroptosis pathway with either necrostatin-1 or by knockdown of RIP1 and RIP3 effectively blocked the cytotoxicity of Chal-24, suggesting that Chal-24-induced cell death is associated with necroptosis. Chal-24 robustly activated JNK and ERK and blockage of which effectively suppressed Chal-24-induced cytotoxicity. In addition, Chal-24 strongly induced autophagy that is dependent on JNK-mediated phosphorylation of Bcl-2 and Bcl-xL and dissociation of Bcl-2 or Bcl-xL from Beclin-1. Importantly, suppression of autophagy, with either pharmacological inhibitors or small interfering RNAs targeting the essential autophagy components ATG7 and Beclin-1, effectively attenuated Chal-24-induced cell death. Furthermore, we found that autophagy activation resulted in c-IAP1 and c-IAP2 degradation and formation of the Ripoptosome that contributes to necroptosis. These results thus establish a novel mechanism for killing cancer cells that involves autophagy-mediated necroptosis, which may be employed for overcoming chemoresistance.

The biological role of monocytes and macrophages in B-cell non-Hodgkin lymphoma (NHL) is not fully understood. We have previously reported that monocytes from patients with B-cell NHL have an immunosuppressive CD14(+)HLA-DR(low/-) phenotype that correlates with a poor prognosis. However, the underlying mechanism by which CD14(+)HLA-DR(low/-) monocytes develop in lymphoma is unknown. In the present study, we found that interleukin (IL)-10, which is increased in the serum of patients with B-cell NHL, induced the development of the CD4(+)HLA-DR(low/-) population. Using peripheral blood samples from patients with B-cell NHL, we found that absolute numbers of CD14(+) monocytic cells with an HLA-DR(low/-) phenotype were higher than healthy controls and correlated with a higher International Prognostic Index score. IL-10 serum levels were elevated in lymphoma patients compared with controls and were associated with increased peripheral monocyte counts. Treatment of monocytes with IL-10 in vitro significantly decreased HLA-DR expression and resulted in the expansion of CD14(+)HLA-DR(low/-) population. We found that lymphoma B cells produce IL-10 and supernatants from cultured lymphoma cells increased the CD14(+)HLA-DR(low/-) population. Furthermore, we found that IL-10-induced CD14(+)HLA-DR(low/-) monocytes inhibited the activation and proliferation of T cells. Taken together, these results suggest that elevated IL-10 serum levels contribute to increased numbers of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell NHL.

The brain and the immune system interact in complex ways after ischemic stroke, and the long-term effects of immune response associated with stroke remain controversial. As a linkage between innate and adaptive immunity, interleukin-17 A (IL-17 A) secreted from gamma delta (γδ) T cells has detrimental roles in the pathogenesis of acute ischemic stroke. However, to date, the long-term actions of IL-17 A after stroke have not been investigated. Here, we found that IL-17 A showed two distinct peaks of expression in the ischemic hemisphere: the first occurring within 3 days and the second on day 28 after stroke. Our data also showed that astrocyte was the major cellular source of IL-17 A that maintained and augmented subventricular zone (SVZ) neural precursor cells (NPCs) survival, neuronal differentiation, and subsequent synaptogenesis and functional recovery after stroke. IL-17 A also promoted neuronal differentiation in cultured NPCs from the ischemic SVZ. Furthermore, our in vitro data revealed that in primary astrocyte cultures activated astrocytes released IL-17 A via p38 mitogen-activated protein kinase (MAPK). Culture media from reactive astrocytes increased neuronal differentiation of NSCs in vitro. Blockade of IL-17 A with neutralizing antibody prevented this effect. In addition, after screening for multiple signaling pathways, we revealed that the p38 MAPK/calpain 1 signaling pathway was involved in IL-17 A-mediated neurogenesis in vivo and in vitro. Thus, our results reveal a previously uncharacterized property of astrocytic IL-17 A in the maintenance and augment of survival and neuronal differentiation of NPCs, and subsequent synaptogenesis and spontaneous recovery after ischemic stroke.

Among a panel of 788 clinical influenza H3N2 isolates, two isolates were characterized by an oseltamivir-resistant phenotype linked to the absence of any detectable NA activity. Here, we established that the two H3NA- isolates lack any detectable full-length NA segment, and one of these could be rescued by reverse genetics in the absence of any NA segment sequence. We found that the absence of NA segment induced a moderate growth defect of the H3NA- viruses as on cultured cells. The glycoproteins density at the surface of H3NA- virions was unchanged as compared to H3N2 virions. The HA protein as well as residues 188 and 617 of the PB1 protein were shown to be strong determinants of the ability of H3NA- viruses to grow in the absence of the NA segment. The significance of these findings about naturally occurring seven-segment influenza A viruses is discussed.

In 2006, the Canadian National Advisory Committee on Blood and Blood Products (NAC) developed a transfusion policy framework for the use of off-label recombinant factor VIIa (rFVIIa) in massive bleeding. Because the number of randomised controlled trials has doubled, the NAC undertook a review of the policy framework in 2011. On the basis of the review of 29 randomised controlled trials, there remains little evidence to support the routine use of rFVIIa in massive bleeding. Mortality benefits have not been demonstrated. Contrarily, an increase in arterial thromboembolic events has been observed with the use of off-label rFVIIa. Given the absence of evidence of benefit and with evidence of the risk of harm, the NAC recommends that recombinant VIIa no longer be used for the off-label indications of prevention and treatment of bleeding in patients without haemophilia.

Stress is a potent etiological factor in the onset of major depressive disorder and posttraumatic stress disorder (PTSD). Therefore, significant efforts have been made to identify factors that produce resilience to the outcomes of a later stressor, in hopes of preventing untoward clinical outcomes. The NMDA receptor antagonist ketamine has recently emerged as a prophylactic capable of preventing neurochemical and behavioral outcomes of a future stressor. Despite promising results of preclinical studies performed in male rats, the effects of proactive ketamine in female rats remains unknown. This is alarming given that stress-related disorders affect females at nearly twice the rate of males. Here we explore the prophylactic effects of ketamine on stress-induced anxiety-like behavior and the neural circuit-level processes that mediate these effects in female rats. Ketamine given one week prior to an uncontrollable stressor (inescapable tailshock; IS) reduced typical stress-induced activation of the serotonergic (5-HT) dorsal raphe nucleus (DRN) and eliminated DRN-dependent juvenile social exploration (JSE) deficits 24 h after the stressor. Proactive ketamine altered prelimbic cortex (PL) neural ensembles so that a later experience with IS now activated these cells, which it ordinarily would not. Ketamine acutely activated a PL to DRN (PL-DRN) circuit and inhibition of this circuit with Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) at the time of IS one week later prevented stress prophylaxis, suggesting that persistent changes in PL-DRN circuit activity are responsible, at least in part, for mediating long-term effects associated with ketamine.

Camouflaging antigens on the surface of cells seems an appealing way to prevent activation of the immune system. We explored the possibility of preventing hyperacute rejection by chemically camouflaging endothelial cells (EC). In vitro as well as in vivo experiments were performed. First, the ability of mPEG coating to prevent antibody-antigen interactions was evaluated. Second, we tested the degree to which mPEG coating prevents activation of EC by stimuli such as TNF-alpha and LPS. Third, in vivo experiments were performed to test the ability of mPEG coating to prolong xenograft survival. We demonstrate that binding of several antibodies to EC or serum proteins can be inhibited by mPEG. Furthermore, binding of TNF-alpha as well as LPS to EC is blocked since mPEG treatment of EC inhibits the subsequent up-regulation of E-selectin by these stimuli. However, in vivo experiments revealed that currently this method alone is not sufficient to prevent hyperacute rejection.

The heavy metal cadmium (Cd) is nephrotoxic. Recent studies show that autophagy plays an essential role in Cd-induced kidney injury. However, the mechanisms of Cd-induced kidney injury accompanied by autophagy are still obscure. In the present study, we first confirmed that Cd induced kidney damage and dysfunction, along with autophagy, both in vivo and in vitro. Then, we observed that cyclooxygenase-2 (COX-2) and the eIF2α-ATF4 pathway of endoplasmic reticulum (ER) stress were induced by Cd in both kidney tissues and cultured cells. Further studies showed that inhibition of COX-2 with celecoxib or RNA interference (RNAi) inhibited the Cd-induced autophagy in kidney cells. In addition, blocking ER stress with 4-phenylbutyrate or RNAi partially counteracted COX-2 overexpression and autophagy induced by Cd, which suggested that ER stress was required for Cd-induced kidney autophagy. Significantly, our results showed that Cd activated ATF4 and induced its translocation to the nucleus. Knockdown of ATF4 inhibited Cd-induced COX-2 overexpression. While COX-2 overexpression is involved in renal dysfunction, there is no prior report on the role of COX-2 in autophagy regulation. The results of the current study suggest a novel molecular mechanism that the ER stress eIF2α-ATF4 pathway-mediated COX-2 overexpression contributes to Cd-induced kidney autophagy and injury. The present study implies that COX-2 may be a potential target for therapy against Cd-induced nephrotoxicity.

Bisphenol A (BPA) is widely used in plastic products, through which humans are exposed to it. Accumulating evidence suggests that BPA exposure is associated with β-cell dysfunction. Mitochondrial defects can cause impairment and failure of β cells, but there is little information about the effects of BPA on the mitochondrial function of β cells. In this study, we assessed the role of mitochondria-mediated mechanisms underlying BPA-induced β-cell dysfunction and resulting β-cell apoptosis. INS-1 cells were cultured with 0, 0.0020, 0.020, 0.20, or 2.0 μM BPA. Cell viability, glucose-stimulated insulin secretion (GSIS), and mitochondrial function were examined. The mitochondrial apoptotic pathway was also analyzed at molecular level. We found that BPA suppressed cell viability and disturbed GSIS in a dose-dependent manner. Positive Annexin- propidium iodide (PI) staining and altered expression of Bcl-2 family members and caspases in INS-1 cells indicated that the cells progressively became apoptotic after BPA exposure. Additionally, BPA-induced apoptosis was associated with mitochondrial defects in β cells, as evidenced by depletion of ATP, release of cytochrome c, loss of mitochondrial mass and membrane potential, and alterations in expression of genes involved in mitochondrial function and metabolism. Taken together, these findings provide strong evidence that BPA triggers INS-1 cells dysfunction and apoptosis may be meditated via the mitochondrial pathway.

Malaria remains a serious public health problem with significant morbidity and mortality. This study was conducted to identify whether ficolin-A could play an active role of against malaria infection.

Cholesterol oxidase (COD), an enzyme catalyzing the oxidation of cholesterol, has been applied to track the distribution of membrane cholesterol. Little investigations about the effect of COD on tumor cells have been performed. In the present study, we provided evidence that COD from Bordetella species (COD-B), induced apoptosis of lung cancer cells in vitro and in vivo. COD-B treatment inhibited Akt and ERK1/2 phosphorylation in dose- and time-dependent manner, which was not reversed and was even aggravated by cholesterol addition. Further investigation indicated that COD-B treatment promoted the generation of reactive oxygen species (ROS) and that cholesterol addition further elevated ROS levels. Moreover, COD-B treatment resulted in JNK and p38 phosphorylation, downregulation of Bcl-2, upregulation of Bax, activated caspase-3 and cytochrome C release, which likely responded to freshly produced hydrogen peroxide that accompanied cholesterol oxidation. Catalase pretreatment could only partially prevent COD-B-induced events, suggesting that catalase inhibited H2O2-induced signal transduction but had little effect on signal pathways involved in cholesterol depletion. Our results demonstrated that COD-B led to irreversible cell apoptosis by decreasing cholesterol content and increasing ROS level. In addition, COD-B may be a promising candidate for a novel anti-tumor therapy.

The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors.

The Treponema pallidum membrane protein Tp47 induces immunocyte adherence to vascular cells and contributes to vascular inflammation. However, it is unclear whether microvesicles are functional inflammatory mediators between vascular cells and immunocytes. Microvesicles that were isolated from Tp47-treated THP-1 cells using differential centrifugation were subjected to adherence assays to determine the adhesion-promoting effect on human umbilical vein endothelial cells (HUVECs). Intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) levels in Tp47-induced microvesicle (Tp47-microvesicle)-treated HUVECs were measured, and the related intracellular signaling pathways of Tp47-microvesicle-induced monocyte adhesion were investigated. Tp47-microvesicles promoted THP-1 cell adhesion to HUVECs (P < 0.01) and upregulated ICAM-1 and VCAM-1 expression in HUVECs (P < 0.001). The adhesion of THP-1 cells to HUVECs was inhibited by anti-ICAM-1 and anti-VCAM-1 neutralizing antibodies. Tp47-microvesicle treatment of HUVECs activated the extracellular signal-regulated kinase 1/2 (ERK1/2) and NF-κB signaling pathways, whereas ERK1/2 and NF-κB inhibition suppressed the expression of ICAM-1 and VCAM-1 and significantly decreased the adhesion of THP-1 cells to HUVECs. IMPORTANCE Tp47-microvesicles promote the adhesion of THP-1 cells to HUVECs through the upregulation of ICAM-1 and VCAM-1 expression, which is mediated by the activation of the ERK1/2 and NF-κB pathways. These findings provide insight into the pathophysiology of syphilitic vascular inflammation.

Although obesity is associated with low-grade inflammation and metabolic disorders, clinical studies suggested some obese people were metabolically healthy with smaller adipocyte size compared with metabolically abnormal obese (MAO). This indicated adipocyte size may be an important predictor underlay the distinction between MAO and metabolically healthy obese. As recent study has shown that adipocytes expressed class II major histocompatibility complex (MHCII), which functioned as APCs during obesity. However, the relationship between adipocyte hypertrophy and MHCII expression was not involved. Here we hypothesize that hypertrophic adipocytes could be associated with upregulating MHCII to influence adipose tissue metabolism.

Deleted in liver cancer 1 (DLC1) is a RhoGTPase activation protein-containing tumor suppressor that associates with various types of cancer. Although DLC2 shares a similar domain structure with that of DLC1, the function of DLC2 is not well characterized. Here, we describe the expression and ablation of DLC2 in mice using a reporter-knockout approach. DLC2 is expressed in several tissues and in endothelial cells (ECs) of blood vessels. Although ECs and blood vessels show no histological abnormalities and mice appear overall healthy, DLC2-mutant mice display enhanced angiogenic responses induced by matrigel and by tumor cells. Silencing of DLC2 in human ECs has reduced cell attachment, increased migration, and tube formation. These changes are rescued by silencing of RhoA, suggesting that the process is RhoA pathway dependent. These results indicate that DLC2 is not required for mouse development and normal vessel formation, but may protect mouse from unwanted angiogenesis induced by, for example, tumor cells.