Efficacy of cell-based immunotherapies on patients with glioma: an umbrella review of systematic reviews and meta-analysis protocol.

INTRODUCTION: Glial brain tumours are highly mortal and are noted as major neurosurgical challenges due to frequent recurrence or progression. Despite standard-of-care treatment for gliomas, the prognosis of patients with higher-grade glial tumours is still poor, and hence empowering antitumour immunity against glioma is a potential future oncological prospect. This review is designed to improve our understanding of the efficacy of cell-based immunotherapies for glioma. METHODS AND ANALYSIS: This systematic review will be performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search of main electronic databases: PubMed/MEDLINE, Scopus, ISI Web of Science EMBASE and ProQuest will be done on original articles, followed by a manual review of review articles. Only records in English and only clinical trials will be encountered for full-text review. All the appropriate studies that encountered the inclusion criteria will be screened, selected and then will undergo data extraction step by two independent authors. For meta-analyses, data heterogeneity for each parameter will be first evaluated by Cochran's Q and I2 statistics. In case of possible heterogeneity, a random-effects meta-analysis will be performed and for homogenous data, fixed-effects models will be selected for reporting the results of the proportional meta-analysis. Bias risk will be assessed through Begg's and Egger's tests and will also be visualised by Funnel plots. ETHICS AND DISSEMINATION: As this study will be a systematic review without human participants' involvement, no ethical registration is required and meta-analysis will be presented at a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022373297.

Bispecific antibodies targeting CTLA-4: game-changer troopers in cancer immunotherapy.

Antibody-based cancer immunotherapy has become a powerful asset in the arsenal against malignancies. In this regard, bispecific antibodies (BsAbs) are a ground-breaking novel approach in the therapy of cancers. Recently, BsAbs have represented a significant advancement in improving clinical outcomes. BsAbs are designed to target two different antigens specifically. Over a hundred various BsAb forms currently exist, and more are constantly being manufactured. An antagonistic regulator of T cell activation is cytotoxic T lymphocyte-associated protein 4 (CTLA-4) or CD152, a second counter-receptor for the B7 family of co-stimulatory molecules was introduced in 1996 by Professor James P. Allison and colleagues. Contrary to the explosive success of dual immune checkpoint blockade for treating cancers, a major hurdle still yet persist is that immune-related adverse events (irAEs) observed by combining immune checkpoint inhibitors (ICIs) or monoclonal antibodies such as ipilimumab (anti-CTLA-4) and nivolumab (anti-PD-1). A promising strategy to overcome this hurdle is using BsAbs. This article will summarize BsAbs targeting CTLA-4, their applications in cancer immunotherapy, and relevant clinical trial advances. We will also discuss the pre-clinical rationale for using these BsAbs, and provide the current landscape of the field.

Tissue-resident, extravascular Ly6c- monocytes are critical for inflammation in the synovium.

Monocytes are abundant immune cells that infiltrate inflamed organs. However, the majority of monocyte studies focus on circulating cells, rather than those in tissue. Here, we identify and characterize an intravascular synovial monocyte population resembling circulating non-classical monocytes and an extravascular tissue-resident monocyte-lineage cell (TR-MC) population distinct in surface marker and transcriptional profile from circulating monocytes, dendritic cells, and tissue macrophages that are conserved in rheumatoid arthritis (RA) patients. TR-MCs are independent of NR4A1 and CCR2, long lived, and embryonically derived. TR-MCs undergo increased proliferation and reverse diapedesis dependent on LFA1 in response to arthrogenic stimuli and are required for the development of RA-like disease. Moreover, pathways that are activated in TR-MCs at the peak of arthritis overlap with those that are downregulated in LFA1-/- TR-MCs. These findings show a facet of mononuclear cell biology that could be imperative to understanding tissue-resident myeloid cell function in RA.

SLAM-family receptors come of age as a potential molecular target in cancer immunotherapy.

The signaling lymphocytic activation molecule (SLAM) family receptors were discovered in immune cells for the first time. The SLAM-family receptors are a significant player in cytotoxicity, humoral immune responses, autoimmune diseases, lymphocyte development, cell survival, and cell adhesion. There is growing evidence that SLAM-family receptors have been involved in cancer progression and heralded as a novel immune checkpoint on T cells. Previous studies have reported the role of SLAMs in tumor immunity in various cancers, including chronic lymphocytic leukemia, lymphoma, multiple myeloma, acute myeloid leukemia, hepatocellular carcinoma, head and neck squamous cell carcinoma, pancreas, lung, and melanoma. Evidence has deciphered that the SLAM-family receptors may be targeted for cancer immunotherapy. However, our understanding in this regard is not complete. This review will discuss the role of SLAM-family receptors in cancer immunotherapy. It will also provide an update on recent advances in SLAM-based targeted immunotherapies.

Advances in therapeutic targeting of immune checkpoints receptors within the CD96-TIGIT axis: clinical implications and future perspectives.

INTRODUCTION: The development of therapeutic antibodies targeting immune checkpoint molecules (ICMs) that induce long-term remissions in cancer patients has revolutionized cancer immunotherapy. However, a major drawback is that relapse after an initial response may be attributed to innate and acquired resistance. Additionally, these treatments are not beneficial to all patients. Therefore, the discovery and targeting of novel ICMs and their combination with other immunotherapeutics are urgently needed. AREAS COVERED: There has been increasing evidence of the CD96-TIGIT axis as ICMs in cancer immunotherapy in the last five years. This review will highlight and discuss the current knowledge about the role of CD96 and TIGIT in hematological and solid tumor immunotherapy in the context of empirical studies and clinical trials, and provide a comprehensive list of ongoing cancer clinical trials on the blockade of these ICMs, as well as the rationale behind combinational therapies with anti-PD-1/PD-L1 agents, chemotherapy drugs, and radiotherapy. Moreover, we share our perspectives on anti-CD96/TIGIT-related combination therapies. EXPERT OPINION: CD96-TIGIT axis regulates anti-tumor immune responses. Thus, the receptors within this axis are the potential candidates for cancer immunotherapy. Combining the inhibition of CD96-TIGIT with anti-PD-1/PD-L1 mAbs and chemotherapy drugs has shown relatively effective results in the context of preclinical studies and tumor models.

Next-Generation Anti-Angiogenic Therapies as a Future Prospect for Glioma Immunotherapy; From Bench to Bedside.

Glioblastoma (grade IV glioma) is the most aggressive histopathological subtype of glial tumors with inordinate microvascular proliferation as one of its key pathological features. Extensive angiogenesis in the tumor microenvironment supplies oxygen and nutrients to tumoral cells; retains their survival under hypoxic conditions; and induces an immunosuppressive microenvironment. Anti-angiogenesis therapy for high-grade gliomas has long been studied as an adjuvant immunotherapy strategy to overcome tumor growth. In the current review, we discussed the underlying molecular mechanisms contributing to glioblastoma aberrant angiogenesis. Further, we discussed clinical applications of monoclonal antibodies, tyrosine kinase inhibitors, and aptamers as three major subgroups of anti-angiogenic immunotherapeutics and their limitations. Moreover, we reviewed clinical and preclinical applications of small interfering RNAs (siRNAs) as the next-generation anti-angiogenic therapeutics and summarized their potential advantages and limitations. siRNAs may serve as next-generation anti-angiogenic therapeutics for glioma. Additionally, application of nanoparticles as a delivery vehicle could increase their selectivity and lower their off-target effects.

Recent advances in passive immunotherapies for COVID-19: The Evidence-Based approaches and clinical trials.

In late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged, causing a global pandemic called COVID-19. Currently, there is no definitive treatment for this emerging disease. Global efforts resulted in developing multiple platforms of COVID-19 vaccines, but their efficacy in humans should be wholly investigated in the long-term clinical and epidemiological follow-ups. Despite the international efforts, COVID-19 vaccination accompanies challenges, including financial and political obstacles, serious adverse effects (AEs), the impossibility of using vaccines in certain groups of people in the community, and viral evasion due to emerging novel variants of SARS-CoV-2 in many countries. For these reasons, passive immunotherapy has been considered a complementary remedy and a promising way to manage COVID-19. These approaches arebased on reduced inflammation due to inhibiting cytokine storm phenomena, immunomodulation,preventing acute respiratory distress syndrome (ARDS), viral neutralization, anddecreased viral load. This article highlights passive immunotherapy and immunomodulation approaches in managing and treating COVID-19 patients and discusses relevant clinical trials (CTs).

A comprehensive update to Dendritic Cell therapy for glioma: a systematic review and meta-analysis.

BACKGROUND: Gliomas are major challenges of neuro-oncology due to high mortality. Clinical applications of dendritic cells (DCs) have yielded promising results in the clinical trial pipelines over decades. RESEARCH DESIGN: In this systematic review, we critically discuss the current status, future perspective, and challenges of DC therapy for gliomas . and summarize the study population, blinding, comparators, dosage, treatment regimens, efficacy, and safety issues of the clinical trials published on DC therapy for gliomas and also report the results of our meta-analysis on safety and immunological efficacy of DC therapy for gliomas. RESULTS: The results of our meta-analysis indicated that the most frequent grade I/II adverse event (AE) reported in phase I or phase I/II trials was fatigue (∼16% and 24%). Moreover, in phase II trials, fatigue and cytopenia were the most common AEs (∼9% and 14%). Meanwhile, Grade III/IV AEs were rare . Moreover, our meta-analysis indicated ∼64% CD8+ T cells infiltration into tumor site after DC therapy and also ∼45% IFNγ increase. CONCLUSIONS: DC therapy could serve as a potential immunotherapy for gliomas; however, limitations exist to draw certain conclusions due to diversity of the criteria applied to assess clinical response and limited data on patients' survival.

A systematic update to circulating extracellular vesicles proteome; transcriptome and small RNA-ome as glioma diagnostic, prognostic and treatment-response biomarkers.

Brain gliomas are major neurosurgical challenges due to high mortality and morbidity. Hence, development of novel biomarkers is of great value to plan appropriate treatment strategy. Evaluation of the molecular content of extracellular vesicles (EVs) as novel non-invasive biomarker repertoires can provide a real-time portrait of disease status. This study aims to provide a systematic, comprehensive and critical report of the diagnostic and prognostic significance of EV biomarkers (proteins, DNAs and RNAs) for brain gliomas, discuss their biogenesis and passage through the blood brain barrier, and also highlight the high throughput methods used for EV biomarker discovery; as well as discussing potential limitations of EV isolation and characterization methods as glioma diagnostic, prognostic or treatment response biomarkers. Moreover, we critically appraise the bias risk in the previous studies, discuss the limitations EV biomarker discovery faces to enter neurosurgical practice in the future, and highlight the need for more optimized protocols for EV isolation and biomarker discovery in high throughput studies. The current systematic review was conducted upon PRISMA guidelines [10].

Potential Antiviral Immune Response Against COVID-19: Lessons Learned from SARS-CoV.

Virus and host innate immune system interaction plays a significant role in forming the outcome of viral diseases. Host innate immunity initially recognizes the viral invasion and induces a rapid inflammatory response, and this recognition activates signaling cascades that trigger the release of antiviral mediators. This chapter aims to explore the mechanisms by which newly emerged coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) activates the host immune system. Since SARS-CoV-2 shares similarities with SARS-CoV that caused the epidemic of SARS in 2003, the pathogenesis of both viruses could be at least very similar. For this, this chapter provides a synthesis of literature concerning antiviral immunity in SARS-CoV and SARS-CoV-2. It includes the presentation of epitopes linked to SARS-CoV-2 as well as the ability of SARS-CoV-2 to cause proteolytic activation and interact with angiotensin-converting enzyme 2 (ACE2) via molecular mimicry. This chapter characterizes various mechanisms that this virus may engage in escaping the host immunity, ended by a discussion of humoral immune responses against SARS-CoV-2.

Crosstalk between nonclassical monocytes and alveolar macrophages mediates transplant ischemia-reperfusion injury through classical monocyte recruitment.

Primary graft dysfunction (PGD) is the predominant cause of early graft loss following lung transplantation. We recently demonstrated that donor pulmonary intravascular nonclassical monocytes (NCM) initiate neutrophil recruitment. Simultaneously, host-origin classical monocytes (CM) permeabilize the vascular endothelium to allow neutrophil extravasation necessary for PGD. Here, we show that a CCL2-CCR2 axis is necessary for CM recruitment. Surprisingly, although intravital imaging and multichannel flow cytometry revealed that depletion of donor NCM abrogated CM recruitment, single cell RNA sequencing identified donor alveolar macrophages (AM) as predominant CCL2 secretors. Unbiased transcriptomic analysis of murine tissues combined with murine KOs and chimeras indicated that IL-1ß production by donor NCM was responsible for the early activation of AM and CCL2 release. IL-1ß production by NCM was NLRP3 inflammasome dependent and inhibited by treatment with a clinically approved sulphonylurea. Production of CCL2 in the donor AM occurred through IL-1R-dependent activation of the PKC and NF-κB pathway. Accordingly, we show that IL-1ß-dependent paracrine interaction between donor NCM and AM leads to recruitment of recipient CM necessary for PGD. Since depletion of donor NCM, IL-1ß, or IL-1R antagonism and inflammasome inhibition abrogated recruitment of CM and PGD and are feasible using FDA-approved compounds, our findings may have potential for clinical translation.

Targeting CD38-dependent NAD+ metabolism to mitigate multiple organ fibrosis.

The processes underlying synchronous multiple organ fibrosis in systemic sclerosis (SSc) remain poorly understood. Age-related pathologies are associated with organismal decline in nicotinamide adenine dinucleotide (NAD+) that is due to dysregulation of NAD+ homeostasis and involves the NADase CD38. We now show that CD38 is upregulated in patients with diffuse cutaneous SSc, and CD38 levels in the skin associate with molecular fibrosis signatures, as well as clinical fibrosis scores, while expression of key NAD+-synthesizing enzymes is unaltered. Boosting NAD+ via genetic or pharmacological CD38 targeting or NAD+ precursor supplementation protected mice from skin, lung, and peritoneal fibrosis. In mechanistic experiments, CD38 was found to reduce NAD+ levels and sirtuin activity to augment cellular fibrotic responses, while inhibiting CD38 had the opposite effect. Thus, we identify CD38 upregulation and resulting disrupted NAD+ homeostasis as a fundamental mechanism driving fibrosis in SSc, suggesting that CD38 might represent a novel therapeutic target.

Maintenance DNA methylation is essential for regulatory T cell development and stability of suppressive function.

Tregs require Foxp3 expression and induction of a specific DNA hypomethylation signature during development, after which Tregs persist as a self-renewing population that regulates immune system activation. Whether maintenance DNA methylation is required for Treg lineage development and stability and how methylation patterns are maintained during lineage self-renewal remain unclear. Here, we demonstrate that the epigenetic regulator ubiquitin-like with plant homeodomain and RING finger domains 1 (Uhrf1) is essential for maintenance of methyl-DNA marks that stabilize Treg cellular identity by repressing effector T cell transcriptional programs. Constitutive and induced deficiency of Uhrf1 within Foxp3+ cells resulted in global yet nonuniform loss of DNA methylation, derepression of inflammatory transcriptional programs, destabilization of the Treg lineage, and spontaneous inflammation. These findings support a paradigm in which maintenance DNA methylation is required in distinct regions of the Treg genome for both lineage establishment and stability of identity and suppressive function.

Residual endotoxin induces primary graft dysfunction through ischemia/reperfusion-primed alveolar macrophages.

Despite the widespread use of antibiotics, bacterial pneumonias in donors strongly predispose to the fatal syndrome of primary graft dysfunction (PGD) following lung transplantation. We report that bacterial endotoxin persists in human donor lungs after pathogen is cleared with antibiotics and is associated with neutrophil infiltration and PGD. In mouse models, depletion of tissue-resident alveolar macrophages (TRAMs) attenuated neutrophil recruitment in response to endotoxin as shown by compartmental staining and intravital imaging. Bone marrow chimeric mice revealed that neutrophils were recruited by TRAM through activation of TLR4 in a MyD88-dependent manner. Intriguingly, low levels of endotoxin, insufficient to cause donor lung injury, promoted TRAM-dependent production of CXCL2, increased neutrophil recruitment, and led to PGD, which was independent of donor NCMs. Reactive oxygen species (ROS) increased in human donor lungs starting from the warm-ischemia phase and were associated with increased transcription and translocation to the plasma membrane of TLR4 in donor TRAMs. Consistently, scavenging ROS or inhibiting their production to prevent TLR4 transcription/translocation or blockade of TLR4 or coreceptor CD14 on donor TRAMs prevented neutrophil recruitment in response to endotoxin and ameliorated PGD. Our studies demonstrate that residual endotoxin after successful treatment of donor bacterial pneumonia promotes PGD through ischemia/reperfusion-primed donor TRAMs.

High CO2 Levels Impair Lung Wound Healing.

Delayed lung repair leads to alveolopleural fistulae, which are a major cause of morbidity after lung resections. We have reported that intrapleural hypercapnia is associated with delayed lung repair after lung resection. Here, we provide new evidence that hypercapnia delays wound closure of both large airway and alveolar epithelial cell monolayers because of inhibition of epithelial cell migration. Cell migration and airway epithelial wound closure were dependent on Rac1-GTPase activation, which was suppressed by hypercapnia directly through the upregulation of AMP kinase and indirectly through inhibition of injury-induced NF-κB-mediated CXCL12 (pleural CXC motif chemokine 12) release, respectively. Both these pathways were independently suppressed, because dominant negative AMP kinase rescued the effects of hypercapnia on Rac1-GTPase in uninjured resting cells, whereas proteasomal inhibition reversed the NF-κB-mediated CXCL12 release during injury. Constitutive overexpression of Rac1-GTPase rescued the effects of hypercapnia on both pathways as well as on wound healing. Similarly, exogenous recombinant CXCL12 reversed the effects of hypercapnia through Rac1-GTPase activation by its receptor, CXCR4. Moreover, CXCL12 transgenic murine recipients of orthotopic tracheal transplantation were protected from hypercapnia-induced inhibition of tracheal epithelial cell migration and wound repair. In patients undergoing lobectomy, we found inverse correlation between intrapleural carbon dioxide and pleural CXCL12 levels as well as between CXCL12 levels and alveolopleural leak. Accordingly, we provide first evidence that high carbon dioxide levels impair lung repair by inhibiting epithelial cell migration through two distinct pathways, which can be restored by recombinant CXCL12.

Clinical relevance of lung-restricted antibodies in lung transplantation.

Lung transplant is a definitive treatment for several end-stage lung diseases. However, the high incidence of allograft rejection limits the overall survival following lung transplantation. Traditionally, alloimmunity directed against human leukocyte antigens (HLA) has been implicated in transplant rejection. Recently, the clinical impact of non-HLA lung-restricted antibodies (LRA) has been recognized and extensive research has demonstrated that they may play a dominant role in the development of lung allograft rejection. The immunogenic lung-restricted antigens that have been identified include amongst others, collagen type I, collagen type V, and k-alpha 1 tubulin. Pre-existing antibodies against these lung-restricted antigens are prevalent in patients undergoing lung transplantation and have emerged as one of the predominant risk factors for primary graft dysfunction which limits short-term survival following lung transplantation. Additionally, LRA have been shown to predispose to chronic lung allograft rejection, the predominant cause of poor long-term survival. This review will discuss ongoing research into the mechanisms of development of LRA as well as the pathogenesis of associated lung allograft injury.

Long-Term Impact of Cytomegalovirus Serologic Status on Lung Transplantation in the United States.

BACKGROUND: Cytomegalovirus (CMV) infection has been associated with poor outcomes after solid organ transplantation. The long-term impact of donor and recipient CMV serological status on lung transplant outcomes remains unclear. Accordingly, we evaluated the impact of donor and recipient CMV status on long-term patients as well as allograft survival after single (SLT) and double lung transplantation (BLT). METHODS: The Scientific Registry of Transplant Recipients was used to track all adult lung transplants in United States from May 2005 to June 2016. Patient mortality and bronchiolitis obliterans syndrome were determined up to 5 years using Cox proportional hazards modeling. Additionally, landmark analysis was performed conditional on survival at 1 year. RESULTS: Compared with donor negative-recipient CMV-IgG negative (D-R-), donor positive-recipient negative (D+R-) and donor positive-recipient positive (D+R+) groups had increased mortality at 1 and 5 years after BLT, with the former demonstrating highest risk. Although mortality was not increased with CMV seropositive donors after SLT at 1 year, both D+R- and D+R+ groups demonstrated greater mortality at 5 years. Risk of bronchiolitis obliterans syndrome was not affected by CMV serological status. Conditional landmark analysis confirmed that lungs from CMV seropositive donors conferred highest risk for long-term mortality. CONCLUSIONS: CMV seronegative recipients undergoing either BLT or SLT from CMV seropositive donors have the highest risk of long-term mortality that extends beyond the first year. Further studies are needed to determine the causes of higher mortality observed in the CMV seronegative recipients and risks and benefits of extension of CMV prophylaxis, particularly in the high-risk group.

Single-Cell Transcriptomic Analysis of Human Lung Provides Insights into the Pathobiology of Pulmonary Fibrosis.

Rationale: The contributions of diverse cell populations in the human lung to pulmonary fibrosis pathogenesis are poorly understood. Single-cell RNA sequencing can reveal changes within individual cell populations during pulmonary fibrosis that are important for disease pathogenesis. Objectives: To determine whether single-cell RNA sequencing can reveal disease-related heterogeneity within alveolar macrophages, epithelial cells, or other cell types in lung tissue from subjects with pulmonary fibrosis compared with control subjects. Methods: We performed single-cell RNA sequencing on lung tissue obtained from eight transplant donors and eight recipients with pulmonary fibrosis and on one bronchoscopic cryobiospy sample from a patient with idiopathic pulmonary fibrosis. We validated these data using in situ RNA hybridization, immunohistochemistry, and bulk RNA-sequencing on flow-sorted cells from 22 additional subjects. Measurements and Main Results: We identified a distinct, novel population of profibrotic alveolar macrophages exclusively in patients with fibrosis. Within epithelial cells, the expression of genes involved in Wnt secretion and response was restricted to nonoverlapping cells. We identified rare cell populations including airway stem cells and senescent cells emerging during pulmonary fibrosis. We developed a web-based tool to explore these data. Conclusions: We generated a single-cell atlas of pulmonary fibrosis. Using this atlas, we demonstrated heterogeneity within alveolar macrophages and epithelial cells from subjects with pulmonary fibrosis. These results support the feasibility of discovery-based approaches using next-generation sequencing technologies to identify signaling pathways for targeting in the development of personalized therapies for patients with pulmonary fibrosis.

Spleen-derived classical monocytes mediate lung ischemia-reperfusion injury through IL-1ß.

Ischemia-reperfusion injury, a form of sterile inflammation, is the leading risk factor for both short-term mortality following pulmonary transplantation and chronic lung allograft dysfunction. While it is well recognized that neutrophils are critical mediators of acute lung injury, processes that guide their entry into pulmonary tissue are not well understood. Here, we found that CCR2+ classical monocytes are necessary and sufficient for mediating extravasation of neutrophils into pulmonary tissue during ischemia-reperfusion injury following hilar clamping or lung transplantation. The classical monocytes were mobilized from the host spleen, and splenectomy attenuated the recruitment of classical monocytes as well as the entry of neutrophils into injured lung tissue, which was associated with improved graft function. Neutrophil extravasation was mediated by MyD88-dependent IL-1ß production by graft-infiltrating classical monocytes, which downregulated the expression of the tight junction-associated protein ZO-2 in pulmonary vascular endothelial cells. Thus, we have uncovered a crucial role for classical monocytes, mobilized from the spleen, in mediating neutrophil extravasation, with potential implications for targeting of recipient classical monocytes to ameliorate pulmonary ischemia-reperfusion injury in the clinic.

A Beginner's Guide to Analysis of RNA Sequencing Data.

Since the first publications coining the term RNA-seq (RNA sequencing) appeared in 2008, the number of publications containing RNA-seq data has grown exponentially, hitting an all-time high of 2,808 publications in 2016 (PubMed). With this wealth of RNA-seq data being generated, it is a challenge to extract maximal meaning from these datasets, and without the appropriate skills and background, there is risk of misinterpretation of these data. However, a general understanding of the principles underlying each step of RNA-seq data analysis allows investigators without a background in programming and bioinformatics to critically analyze their own datasets as well as published data. Our goals in the present review are to break down the steps of a typical RNA-seq analysis and to highlight the pitfalls and checkpoints along the way that are vital for bench scientists and biomedical researchers performing experiments that use RNA-seq.