Fe65-engineered neuronal exosomes encapsulating corynoxine-B ameliorate cognition and pathology of Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the predominant impairment of neurons in the hippocampus and the formation of amyloid plaques, hyperphosphorylated tau protein, and neurofibrillary tangles in the brain. The overexpression of amyloid-ß precursor protein (APP) in an AD brain results in the binding of APP intracellular domain (AICD) to Fe65 protein via the C-terminal Fe65-PTB2 interaction, which then triggers the secretion of amyloid-ß and the consequent pathogenesis of AD. Apparently, targeting the interaction between APP and Fe65 can offer a promising therapeutic approach for AD. Recently, exosome, a type of extracellular vesicle with diameter around 30-200 nm, has gained much attention as a potential delivery tool for brain diseases, including AD, due to their ability to cross the blood-brain barrier, their efficient uptake by autologous cells, and their ability to be surface-modified with target-specific receptor ligands. Here, the engineering of hippocampus neuron cell-derived exosomes to overexpress Fe65, enabled the development of a novel exosome-based targeted drug delivery system, which carried Corynoxine-B (Cory-B, an autophagy inducer) to the APP overexpressed-neuron cells in the brain of AD mice. The Fe65-engineered HT22 hippocampus neuron cell-derived exosomes (Fe65-EXO) loaded with Cory-B (Fe65-EXO-Cory-B) hijacked the signaling and blocked the natural interaction between Fe65 and APP, enabling APP-targeted delivery of Cory-B. Notably, Fe65-EXO-Cory-B induced autophagy in APP-expressing neuronal cells, leading to amelioration of the cognitive decline and pathogenesis in AD mice, demonstrating the potential of Fe65-EXO-Cory-B as an effective therapeutic intervention for AD.

Consistent neutralization of circulating omicron sub-variants by hybrid immunity up to 6 months after booster vaccination.

The current COVID-19 vaccination program requires frequent booster vaccination to maintain sufficient neutralization levels against immune evasive SARS-CoV-2 variants. However, prior studies found more potent and durable immune response in convalescing individuals, raising the possibility of less frequent booster vaccination for them. Here, we conducted a longitudinal immunological study based on two prospective cohorts of booster vaccinated convalescing COVID-19 patients or healthcare workers (HCW) without COVID-19 history in Xiangyang, China. Comparing to 1-month post-boosting, pseudovirus neutralization titers (pVNT50) of ancestral Wuhan-Hu-1 and circulating omicron sub-variants BA.5, BF.7, BA.4.6, BA.2.75, and BA.2.75.2 spikes were stable or even increased in convalescing samples at 6-month post-boosting, when HCW samples showed substantial drop of neutralization titers across the spectrum. Variant-to-Wuhan-Hu-1 pVNT50 ratios showed no significant variation during the 17 months from pre-vaccination to 6-month post-boosting in convalescing individuals, indicating that the high durability of hybrid immunity was likely sustained by continuously improving neutralization potency that compensated immune decay. Our data provide mechanistic insight into prior epidemiological findings that vaccine-elicited humoral immune response was more durable in convalescing individuals than those without SARS-CoV-2 infection, and suggest further research into potential extension of boosting intervals for convalescing individuals.

EBV latent membrane protein 1 augments γδ T cell cytotoxicity against nasopharyngeal carcinoma by induction of butyrophilin molecules.

Nasopharyngeal carcinoma (NPC) is a diverse cancer with no well-defined tumor antigen, associated with oncogenic Epstein-Barr Virus (EBV), and with usually late-stage diagnosis and survival <40%. Current radiotherapy and chemotherapy have low effectiveness and cause adverse effects, which calls for the need of new therapy. In this regard, adoptive immunotherapy using γδ T cells has potential, but needs to be coupled with butyrophilin 2A1 and 3A1 protein expression to achieve tumoricidal effect. Methods: Human γδ T cells were expanded (with Zol or PTA) and used for cytotoxicity assay against NPC cells, which were treated with the EBV EBNA1-targeting peptide (L2)P4. Effect of (L2)P4 on BTN2A1/BTN3A1 expression in NPC cells was examined by flow cytometry and Western blot. An NPC-bearing NSG mice model was established to test the effectiveness of P4 and adoptive γδ T cells. Immunofluorescence was performed on NPC tissue sections to examine the presence of γδ T cells and expression of BTN2A1 and BTN3A1. EBV gene expression post-(L2)P4 treatment was assessed by qRT-PCR, and the relationship of LMP1, NLRC5 and BTN2A1/BTN3A1 was examined by transfection, reporter assay, Western blot, and inhibition experiments. Results: Zol- or PTA-expanded the Vδ2 subset of γδ T cells that exerted killing against certain NPC cells. (L2)P4 reactivates latent EBV, which increased BTN2A1 and BTN3A1 expression and conferred higher susceptibility towards Vδ2 T cells cytotoxicity in vitro, as well as enhanced tumor regression in vivo by adoptive transfer of Vδ2 T cells. Mechanistically, (L2)P4 induced EBV LMP1, leading to IFN-γ/p-JNK and NLRC5 activation, and subsequently stimulated the expression of BTN2A1 and BTN3A1. Conclusions: This study demonstrated the effectiveness of using the EBV-targeting probe (L2)P4 and adoptive γδ T cells as a promising combinatorial immunotherapy against NPC. The identification of the LMP1-IFN-γ/p-JNK-NLRC5-BTN2A1/BTN3A1 axis may lead to new insight and therapeutic targets against NPC and other EBV+ tumors.

Association of human cytomegalovirus in urine with end-organ diseases in stage 2/3 HIV-1-infected individuals.

BACKGROUND: Human cytomegalovirus (HCMV) is prevalent in human immunodeficiency virus type 1 (HIV-1)-infected individuals but is suppressed by the host immune system bolstered by antiretroviral therapy. During stage 4 of HIV-1 infection, HCMV becomes a major risk factor for end-organ diseases (EODs). However, the implications of detecting HCMV in patients with stage 2/3 HIV-1 infection have not been established. OBJECTIVES: Conduct a retrospective study of the relationship between HCMV-DNA detection and EODs in patients with stage 2/3 HIV-1 infection. STUDY DESIGN: We cross-sectionally analyzed data from 134,881 HIV-1-infected patients who visited the Third People's Hospital of Shenzhen (Guangdong, China) between January 2011 and June 2022. Only patients with available data on CD4 counts, HIV-RNA and HCMV-DNA copy numbers, and hospitalized stage 2/3 patients with detailed clinical assessments of EODs were included in this study. The chi-square test and Cox regression model were used to examine the association between HCMV-DNA detection and EOD incidence. Longitudinal analysis was performed to examine the effect of anti-HCMV treatment on the incidence of lung and cardiovascular EODs. RESULTS: HCMV-DNA had been tested in the blood and urine of 98.6% and 31.8% of the HIV-1-infected patients, respectively. An increased percentage of HCMV was detected in urine (> 2.4-fold) than in blood at different HIV-1 infection stages. In stage 2/3 patients (n = 454), a higher incidence of EODs was observed in those who tested positive for HCMV-DNA in urine (P < 0.0001) than in those who tested positive for HCMV-DNA in blood (P = 0.0977). Using a model for incidence of EODs, we found that HCMV-DNA detection in urine was associated with an increased incidence of lung EOD; the adjusted hazard ratio (HR) was 1.939 (95% confidence interval [CI]: 1.326-2.761, P = 0.0003) for the HCMVurine+ subgroup and 0.933 (95% CI: 0.523-1.623, P = 0.8605) for the HCMVurine- subgroup. A significant HR was also observed for cardiovascular EOD, which was 0.696 (95% CI: 0.492-0.953, P = 0.0302) for the HCMVurine+ group and 1.56 (95% CI: 0.766-3.074, P = 0.2033) for the HCMVurine- group. Longitudinal analysis showed that treatment for HCMV reduced the incidence rates of lung and cardiovascular EODs in the stage 2/3 patients. CONCLUSIONS: The presence of HCMV in urine is associated with the early prognosis of EODs in patients with stage 2/3 HIV-1 infection and its detection should be implemented as a routine test.

Klotho an Autophagy Stimulator as a Potential Therapeutic Target for Alzheimer's Disease: A Review.

Alzheimer's disease (AD) is an age-associated neurodegenerative disease; it is the most common cause of senile dementia. Klotho, a single-pass transmembrane protein primarily generated in the brain and kidney, is active in a variety of metabolic pathways involved in controlling neurodegeneration and ageing. Recently, many studies have found that the upregulation of Klotho can improve pathological cognitive deficits in an AD mice model and have demonstrated that Klotho plays a role in the induction of autophagy, a major contributing factor for AD. Despite the close association between Klotho and neurodegenerative diseases, such as AD, the underlying mechanism by which Klotho contributes to AD remains poorly understood. In this paper, we will introduce the expression, location and structure of Klotho and its biological functions. Specifically, this review is devoted to the correlation of Klotho protein and the AD phenotype, such as the effect of Klotho in upregulating the amyloid-beta clearance and in inducing autophagy for the clearance of toxic proteins, by regulating the autophagy lysosomal pathway (ALP). In summary, the results of multiple studies point out that targeting Klotho would be a potential therapeutic strategy in AD treatment.