Unveiling the Link: Exploring Mitochondrial Dysfunction as a Probable Mechanism of Hepatic Damage in Post-Traumatic Stress Syndrome.

PTSD is associated with disturbed hepatic morphology and metabolism. Neuronal mitochondrial dysfunction is considered a subcellular determinant of PTSD, but a link between hepatic mitochondrial dysfunction and hepatic damage in PTSD has not been demonstrated. Thus, the effects of experimental PTSD on the livers of high anxiety (HA) and low anxiety (LA) rats were compared, and mitochondrial determinants underlying the difference in their hepatic damage were investigated. Rats were exposed to predator stress for 10 days. Then, 14 days post-stress, the rats were evaluated with an elevated plus maze and assigned to HA and LA groups according to their anxiety index. Experimental PTSD caused dystrophic changes in hepatocytes of HA rats and hepatocellular damage evident by increased plasma ALT and AST activities. Mitochondrial dysfunction was evident as a predominance of small-size mitochondria in HA rats, which was positively correlated with anxiety index, activities of plasma transaminases, hepatic lipids, and negatively correlated with hepatic glycogen. In contrast, LA rats had a predominance of medium-sized mitochondria. Thus, we show links between mitochondrial dysfunction, hepatic damage, and heightened anxiety in PTSD rats. These results will provide a foundation for future research on the role of hepatic dysfunction in PTSD pathogenesis.

Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

mRNA-based precision targeting of neoantigens and tumor-associated antigens in malignant brain tumors.

BACKGROUND: Despite advancements in the successful use of immunotherapy in treating a variety of solid tumors, applications in treating brain tumors have lagged considerably. This is due, at least in part, to the lack of well-characterized antigens expressed within brain tumors that can mediate tumor rejection; the low mutational burden of these tumors that limits the abundance of targetable neoantigens; and the immunologically "cold" tumor microenvironment that hampers the generation of sustained and productive immunologic responses. The field of mRNA-based therapeutics has experienced a boon following the universal approval of COVID-19 mRNA vaccines. mRNA-based immunotherapeutics have also garnered widespread interest for their potential to revolutionize cancer treatment. In this study, we developed a novel and scalable approach for the production of personalized mRNA-based therapeutics that target multiple tumor rejection antigens in a single therapy for the treatment of refractory brain tumors. METHODS: Tumor-specific neoantigens and aberrantly overexpressed tumor-associated antigens were identified for glioblastoma and medulloblastoma tumors using our cancer immunogenomics pipeline called Open Reading Frame Antigen Network (O.R.A.N). Personalized tumor antigen-specific mRNA vaccine was developed for each individual tumor model using selective gene capture and enrichment strategy. The immunogenicity and efficacy of the personalized mRNA vaccines was evaluated in combination with anti-PD-1 immune checkpoint blockade therapy or adoptive cellular therapy with ex vivo expanded tumor antigen-specific lymphocytes in highly aggressive murine GBM models. RESULTS: Our results demonstrate the effectiveness of the antigen-specific mRNA vaccines in eliciting robust anti-tumor immune responses in GBM hosts. Our findings substantiate an increase in tumor-infiltrating lymphocytes characterized by enhanced effector function, both intratumorally and systemically, after antigen-specific mRNA-directed immunotherapy, resulting in a favorable shift in the tumor microenvironment from immunologically cold to hot. Capacity to generate personalized mRNA vaccines targeting human GBM antigens was also demonstrated. CONCLUSIONS: We have established a personalized and customizable mRNA-therapeutic approach that effectively targets a plurality of tumor antigens and demonstrated potent anti-tumor response in preclinical brain tumor models. This platform mRNA technology uniquely addresses the challenge of tumor heterogeneity and low antigen burden, two key deficiencies in targeting the classically immunotherapy-resistant CNS malignancies, and possibly other cold tumor types.

Adeno-associated virus delivered CXCL9 sensitizes glioblastoma to anti-PD-1 immune checkpoint blockade.

There are numerous mechanisms by which glioblastoma cells evade immunological detection, underscoring the need for strategic combinatorial treatments to achieve appreciable therapeutic effects. However, developing combination therapies is difficult due to dose-limiting toxicities, blood-brain-barrier, and suppressive tumor microenvironment. Glioblastoma is notoriously devoid of lymphocytes driven in part by a paucity of lymphocyte trafficking factors necessary to prompt their recruitment and activation. Herein, we develop a recombinant adeno-associated virus (AAV) gene therapy that enables focal and stable reconstitution of the tumor microenvironment with C-X-C motif ligand 9 (CXCL9), a powerful call-and-receive chemokine for lymphocytes. By manipulating local chemokine directional guidance, AAV-CXCL9 increases tumor infiltration by cytotoxic lymphocytes, sensitizing glioblastoma to anti-PD-1 immune checkpoint blockade in female preclinical tumor models. These effects are accompanied by immunologic signatures evocative of an inflamed tumor microenvironment. These findings support AAV gene therapy as an adjuvant for reconditioning glioblastoma immunogenicity given its safety profile, tropism, modularity, and off-the-shelf capability.

CXCL9 recombinant adeno-associated virus (AAV) virotherapy sensitizes glioblastoma (GBM) to anti-PD-1 immune checkpoint blockade.

The promise of immunotherapy to induce long-term durable responses in conventionally treatment resistant tumors like glioblastoma (GBM) has given hope for patients with a dismal prognosis. Yet, few patients have demonstrated a significant survival benefit despite multiple clinical trials designed to invigorate immune recognition and tumor eradication. Insights gathered over the last two decades have revealed numerous mechanisms by which glioma cells resist conventional therapy and evade immunological detection, underscoring the need for strategic combinatorial treatments as necessary to achieve appreciable therapeutic effects. However, new combination therapies are inherently difficult to develop as a result of dose-limiting toxicities, the constraints of the blood-brain barrier, and the suppressive nature of the GBM tumor microenvironment (TME). GBM is notoriously devoid of lymphocytes driven in part by a paucity of lymphocyte trafficking factors necessary to prompt their recruitment, infiltration, and activation. We have developed a novel recombinant adeno-associated virus (AAV) gene therapy strategy that enables focal and stable reconstitution of the GBM TME with C-X-C motif ligand 9 (CXCL9), a powerful call-and-receive chemokine for cytotoxic T lymphocytes (CTLs). By precisely manipulating local chemokine directional guidance, AAV-CXCL9 increases tumor infiltration by CD8-postive cytotoxic lymphocytes, sensitizing GBM to anti-PD-1 immune checkpoint blockade (ICB). These effects are accompanied by immunologic signatures evocative of an inflamed and responsive TME. These findings support targeted AAV gene therapy as a promising adjuvant strategy for reconditioning GBM immunogenicity given its excellent safety profile, TME-tropism, modularity, and off-the-shelf capability, where focal delivery bypasses the constrains of the blood-brain barrier, further mitigating risks observed with high-dose systemic therapy.

Immunotherapy reverses glioma-driven dysfunction of immune system homeostasis.

BACKGROUND: Glioma-induced immune dysregulation of the hematopoietic system has been described in a limited number of studies. In this study, our group further demonstrates that gliomas interrupt the cellular differentiation programming and outcomes of hematopoietic stem and progenitor cells (HSPCs) in the bone marrow. HSPCs from glioma-bearing mice are reprogrammed and driven towards expansion of myeloid lineage precursors and myeloid-derived suppressor cells (MDSCs) in secondary lymphoid organs. However, we found this expansion is reversed by immunotherapy. Adoptive cellular therapy (ACT) has been demonstrably efficacious in multiple preclinical models of central nervous system (CNS) malignancies, and here we describe how glioma-induced dysfunction is reversed by this immunotherapeutic platform. METHODS: The impact of orthotopic KR158B-luc glioma on HSPCs was evaluated in an unbiased fashion using single cell RNAseq (scRNAseq) of lineage- cells and phenotypically using flow cytometry. Mature myeloid cell frequencies and function were also evaluated using flow cytometry. Finally, ACT containing total body irradiation, tumor RNA-pulsed dendritic cells, tumor-reactive T cells and HSPCs isolated from glioma-bearing or non-tumor-bearing mice were used to evaluate cell fate differentiation and survival. RESULTS: Using scRNAseq, we observed an altered HSPC landscape in glioma-bearing versus non-tumor-bearing mice . In addition, an expansion of myeloid lineage subsets, including granulocyte macrophage precursors (GMPs) and MDSCs, were observed in glioma-bearing mice relative to non-tumor-bearing controls. Furthermore, MDSCs from glioma-bearing mice demonstrated increased suppressive capacity toward tumor-specific T cells as compared with MDSCs from non-tumor-bearing hosts. Interestingly, treatment with ACT overcame these suppressive properties. When HSPCs from glioma-bearing mice were transferred in the context of ACT, we observed significant survival benefit and long-term cures in orthotopic glioma models compared with mice treated with ACT using non-glioma-bearing HSPCs.

RNA-sequencing reveals transcriptional signature of pathological remodeling in the diaphragm of rats after myocardial infarction.

The diaphragm is the main inspiratory muscle, and the chronic phase post-myocardial infarction (MI) is characterized by diaphragm morphological, contractile, and metabolic abnormalities. However, the mechanisms of diaphragm weakness are not fully understood. In the current study, we aimed to identify the transcriptome changes associated with diaphragm abnormalities in the chronic stage MI. We ligated the left coronary artery to cause MI in rats and performed RNA-sequencing (RNA-Seq) in diaphragm samples 16 weeks post-surgery. The sham group underwent thoracotomy and pericardiotomy but no artery ligation. We identified 112 differentially expressed genes (DEGs) out of a total of 9664 genes. Myocardial infarction upregulated and downregulated 42 and 70 genes, respectively. Analysis of DEGs in the framework of skeletal muscle-specific biological networks suggest remodeling in the neuromuscular junction, extracellular matrix, sarcomere, cytoskeleton, and changes in metabolism and iron homeostasis. Overall, the data are consistent with pathological remodeling of the diaphragm and reveal potential biological targets to prevent diaphragm weakness in the chronic stage MI.

Immunologic activity and safety of autologous HIV RNA-electroporated dendritic cells in HIV-1 infected patients receiving antiretroviral therapy.

Immunogenicity, manufacturing feasibility, and safety of a novel, autologous dendritic cell (DC)-based immunotherapy (AGS-004) was evaluated in ten human immunodeficiency virus type 1 (HIV-1)-infected adults successfully treated with antiretroviral therapy (ART). Personalized AGS-004 was produced from autologous monocyte-derived DCs electroporated with RNA encoding CD40L and HIV antigens (Gag, Vpr, Rev, and Nef) derived from each subjects' pre-ART plasma. Patients received monthly injections of AGS-004 in combination with ART. AGS-004 was produced within a mean of 6 weeks and yielded 4-12 doses/subject Full or partial HIV-specific proliferative immune responses occurred in 7 of 9 evaluable subjects. Responses were specific for the AGS-004 presented HIV antigens and preferentially targeted CD8(+) T cells. Mild adverse events included flu-like symptoms, fatigue, and injection site reactions. No evidence of autoimmunity, changes in viral load, or significant changes in absolute CD4(+) and CD8(+) T cell counts were observed. This pilot study supports the further clinical investigation of AGS-004.

Immune Escape After Adoptive T-cell Therapy for Malignant Gliomas.

PURPOSE: Immunotherapy has been demonstrably effective against multiple cancers, yet tumor escape is common. It remains unclear how brain tumors escape immunotherapy and how to overcome this immune escape. EXPERIMENTAL DESIGN: We studied KR158B-luc glioma-bearing mice during treatment with adoptive cellular therapy (ACT) with polyclonal tumor-specific T cells. We tested the immunogenicity of primary and escaped tumors using T-cell restimulation assays. We used flow cytometry and RNA profiling of whole tumors to further define escape mechanisms. To treat immune-escaped tumors, we generated escape variant-specific T cells through the use of escape variant total tumor RNA and administered these cells as ACT. In addition, programmed cell death protein-1 (PD-1) checkpoint blockade was studied in combination with ACT. RESULTS: Escape mechanisms included a shift in immunogenic tumor antigens, downregulation of MHC class I, and upregulation of checkpoint molecules. Polyclonal T cells specific for escape variants displayed greater recognition of escaped tumors than primary tumors. When administered as ACT, these T cells prolonged median survival of escape variant-bearing mice by 60%. The rational combination of ACT with PD-1 blockade prolonged median survival of escape variant glioma-bearing mice by 110% and was dependent upon natural killer cells and T cells. CONCLUSIONS: These findings suggest that the immune landscape of brain tumors are markedly different postimmunotherapy yet can still be targeted with immunotherapy.

Autologous HIV-1 clade-B Nef peptides elicit increased frequency, breadth and function of CD8+ T-cells compared to consensus peptides.

OBJECTIVE: To determine the function and phenotype of CD8(+) T-cells targeting consensus and autologous sequences of entire HIV-1 Nef protein. METHODS: Multiparameter flow cytometry-based analysis was used to evaluate the responses of two treatment naïve HIV-infected individuals, during primary and the chronic phases of infection. RESULTS: A greater breadth and magnitude of CD8 IFN-γ responses to autologous compared to clade-B consensus peptides was observed in both subjects. Cross recognition between autologous and consensus peptides decreased in both subjects during progression from primary to chronic infection. The frequencies of TEMRA and TEM CD8(+) T-cells targeting autologous peptides were higher than those targeting consensus peptides and were more polyfunctional (IFN-γ(+) Gr-B(+) CD107a(+)). CONCLUSIONS: Our data indicate superior sensitivity and specificity of autologous peptides. The functional and maturational aspects of "real" versus "cross-recognized" responses were also found to differ, highlighting the importance of a sequence-specific approach towards understanding HIV immune response.

Thioredoxin induced antioxidant gene expressions in human lens epithelial cells.

Thioredoxin (Trx) is one of the major redox-regulating proteins. It catalyzes dithiol/disulfide exchange reactions and displays many unique intracellular and extracellular activities thereby controlling multiple mammalian cell functions. In the present study we examine the effect of exogenous Trx on the expression of several antioxidant genes in human lens epithelial (HLE B3) cells. mRNA levels for gene expression were monitored by RT-PCR and real-time PCR while protein levels were measured by western blot analysis. We have found that recombinant human Trx (hTrx)-treated HLE B3 cells have a simultaneous increase in mRNA expressions of mitochondrial manganese superoxide dismutase (MnSOD), thioltranferase 1 (TTase 1) or glutaredoxin 1 (Grx1), mitochondrial thioltransferase (TTase 2) or glutaredoxin 2 (Grx2), and thioredoxin peroxidase IV (Prx IV). The increased MnSOD and TTase 1 mRNA expressions were accompanied with their respective increases in protein levels. Other antioxidant genes, including Cu/ZnSOD, catalase, glutathione peroxidase 1 (GPx1), thioredoxin reductase 1 (TrxR1), thioredoxin peroxidase III (Prx III), and gamma-glutamyl cysteine synthetase were not affected. The ability of Trx to induce selectively these antioxidant genes in the absence of oxidative stress suggest a cytokine/growth factor-like new physiological role of hTrx in HLE B3 cells. Our data also provide evidence of a strong antioxidant defense system in HLE B3 cells that can be activated by extracellular hTrx, as well as of a possible link between the thioredoxin (Trx) and glutathione (GSH) redox regulating systems in these cells.

Developmental changes in opioid peptides and their receptors in Cpe(fat)/Cpe(fat) mice lacking peptide processing enzyme carboxypeptidase E.

Carboxypeptidase E (CPE) is involved in the biosynthesis of a number of neuropeptides including opioid peptides. A point mutation in this gene results in a loss of enzyme activity, decrease in mature neuroendocrine peptides, and development of late onset obesity as seen in Cpe(fat)/Cpe(fat) mice. In this study, we examined the processing of peptides derived from prodynorphin and proenkephalin in various brain regions of these mice during development. At 6 to 8 weeks, an age prior to the onset of obesity, levels of dynorphin peptides are decreased in all brain regions, whereas levels of ir-Met-enkephalin are differentially altered. There is an accumulation of C-terminally extended forms of all three opioid peptides in Cpe(fat)/Cpe(fat) mice, consistent with a lack of CPE activity. Thus, it appears that there is no direct correlation between the level of mature opioid peptides and the development of obesity in these mice. Since altered levels of peptides can influence the opioid receptor system, we examined the functional activity of mu and kappa opioid receptors using [35S]guanosine-5'-O-(gamma-thio)-triphosphate binding assays. We find no differences in kappa receptor activity in Cpe(fat)/Cpe(fat) compared with control littermate mice. In contrast, the mu receptor activity is differentially altered in select regions of Cpe(fat)/Cpe(fat) mice in response to a mu-specific ligand. Taken together, these results suggest that the lack of CPE activity leads to alterations in the level of opioid peptides during development and that changes in peptide levels differentially affect opioid receptor activity in vivo.