A genetically engineered, stem-cell-derived cellular vaccine.

Despite rapid clinical translation of COVID-19 vaccines in response to the global pandemic, an opportunity remains for vaccine technology innovation to address current limitations and meet challenges of inevitable future pandemics. We describe a universal vaccine cell (UVC) genetically engineered to mimic natural physiological immunity induced upon viral infection of host cells. Cells engineered to express the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike as a representative viral antigen induce robust neutralizing antibodies in immunized non-human primates.

Multiomics analysis couples mRNA turnover and translational control of glutamine metabolism to the differentiation of the activated CD4 T cell.

The ZFP36 family of RNA-binding proteins acts post-transcriptionally to repress translation and promote RNA decay. Studies of genes and pathways regulated by the ZFP36 family in CD4 T cells have focussed largely on cytokines, but their impact on metabolic reprogramming and differentiation is unclear. Using CD4 T cells lacking Zfp36 and Zfp36l1, we combined the quantification of mRNA transcription, stability, abundance and translation with crosslinking immunoprecipitation and metabolic profiling to determine how they regulate T cell metabolism and differentiation.

Immunomodulatory role of mitochondrial DAMPs: a missing link in pathology?

In accordance with the endosymbiotic theory, mitochondrial components bear characteristic prokaryotic signatures, which act as immunomodulatory molecules when released into the extramitochondrial compartment. These endogenous immune triggers, called mitochondrial damage-associated molecular patterns (mtDAMPs), have been implicated in the pathogenesis of various diseases, yet their role remains largely unexplored. In this review, we summarise the available literature on mtDAMPs in diseases, with a special focus on respiratory diseases.

The timing of differentiation and potency of CD8 effector function is set by RNA binding proteins.

CD8 T cell differentiation into effector cells is initiated early after antigen encounter by signals from the T cell antigen receptor and costimulatory molecules. The molecular mechanisms that establish the timing and rate of differentiation however are not defined. Here we show that the RNA binding proteins (RBP) ZFP36 and ZFP36L1 limit the rate of differentiation of activated naïve CD8 T cells and the potency of the resulting cytotoxic lymphocytes.

Virus Induced Lymphocytes (VIL) as a novel viral antigen-specific T cell therapy for COVID-19 and potential future pandemics.

The a priori T cell repertoire and immune response against SARS-CoV-2 viral antigens may explain the varying clinical course and prognosis of patients having a mild COVID-19 infection as opposed to those developing more fulminant multisystem organ failure and associated mortality. Using a novel SARS-Cov-2-specific artificial antigen presenting cell (aAPC), coupled with a rapid expansion protocol (REP) as practiced in tumor infiltrating lymphocytes (TIL) therapy, we generate an immune catalytic quantity of Virus Induced Lymphocytes (VIL). Using T cell receptor (TCR)-specific aAPCs carrying co-stimulatory molecules and major histocompatibility complex (MHC) class-I immunodominant SARS-CoV-2 peptide-pentamer complexes, we expand virus-specific VIL derived from peripheral blood mononuclear cells (PBMC) of convalescent COVID-19 patients up to 1000-fold.

Cardiolipin-mediated PPARγ S112 phosphorylation impairs IL-10 production and inflammation resolution during bacterial pneumonia.

Bacterial pneumonia is a global healthcare burden, and unwarranted inflammation is suggested as an important cause of mortality. Optimum levels of the anti-inflammatory cytokine IL-10 are essential to reduce inflammation and improve survival in pneumonia. Elevated levels of the mitochondrial-DAMP cardiolipin (CL), reported in tracheal aspirates of pneumonia patients, have been shown to block IL-10 production from lung MDSCs.

PI3Kδ hyper-activation promotes development of B cells that exacerbate Streptococcus pneumoniae infection in an antibody-independent manner.

Streptococcus pneumoniae is a major cause of pneumonia and a leading cause of death world-wide. Antibody-mediated immune responses can confer protection against repeated exposure to S. pneumoniae, yet vaccines offer only partial protection.

Severe asthma in humans and mouse model suggests a CXCL10 signature underlies corticosteroid-resistant Th1 bias.

We previously showed that Th1/type 1 inflammation marked by increased IFN-γ levels in the airways can be appreciated in 50% of patients with severe asthma, despite high dose corticosteroid (CS) treatment. We hypothesized that a downstream target of IFN-γ, CXCL10, which recruits Th1 cells via the cognate receptor CXCR3, is an important contributor to Th1high asthma and CS unresponsiveness. We show high levels of CXCL10 mRNA closely associated with IFNG levels in the BAL cells of 50% of severe asthmatics and also in the airways of mice subjected to a severe asthma model, both in the context of high-dose CS treatment.

IRF5 distinguishes severe asthma in humans and drives Th1 phenotype and airway hyperreactivity in mice.

Severe asthma (SA) is a significant problem both clinically and economically, given its poor response to corticosteroids (CS). We recently reported a complex type 1-dominated (IFN-γ-dominated) immune response in more than 50% of severe asthmatics despite high-dose CS treatment. Also, IFN-γ was found to be critical for increased airway hyperreactivity (AHR) in our model of SA.

The mito-DAMP cardiolipin blocks IL-10 production causing persistent inflammation during bacterial pneumonia.

Bacterial pneumonia is a significant healthcare burden worldwide. Failure to resolve inflammation after infection precipitates lung injury and an increase in morbidity and mortality. Gram-negative bacteria are common in pneumonia and increased levels of the mito-damage-associated molecular pattern (DAMP) cardiolipin can be detected in the lungs.

Mitochondrial H2O2 in Lung Antigen-Presenting Cells Blocks NF-κB Activation to Prevent Unwarranted Immune Activation.

Inhalation of environmental antigens such as allergens does not always induce inflammation in the respiratory tract. While antigen-presenting cells (APCs), including dendritic cells and macrophages, take up inhaled antigens, the cell-intrinsic molecular mechanisms that prevent an inflammatory response during this process, such as activation of the transcription factor NF-κB, are not well understood. Here, we show that the nuclear receptor PPARγ plays a critical role in blocking NF-κB activation in response to inhaled antigens to preserve immune tolerance.

Cutting Edge: Dual Function of PPARγ in CD11c+ Cells Ensures Immune Tolerance in the Airways.

The respiratory tract maintains immune homeostasis despite constant provocation by environmental Ags. Failure to induce tolerogenic responses to allergens incites allergic inflammation. Despite the understanding that APCs have a crucial role in maintaining immune tolerance, the underlying mechanisms are poorly understood.

Challenges and future in vaccines, drug development, and immunomodulatory therapy.

Pulmonary diseases and infections are among the top contributors to human morbidity and mortality worldwide, and despite the successful history of vaccines and antimicrobial therapeutics, infectious disease still presents a significant threat to human health. Effective vaccines are frequently unavailable in developing countries, and successful vaccines have yet to be developed for major global maladies, such as tuberculosis. Furthermore, antibiotic resistance poses a growing threat to human health.

Cutting Edge: MMP-9 inhibits IL-23p19 expression in dendritic cells by targeting membrane stem cell factor affecting lung IL-17 response.

We reported previously that c-kit ligation by membrane-bound stem cell factor (mSCF) boosts IL-6 production in dendritic cells (DCs) and a Th17-immune response. However, Th17 establishment also requires heterodimeric IL-23, but the mechanisms that regulate IL-23 gene expression in DCs are not fully understood. We show that IL-23p19 gene expression in lung DCs is dependent on mSCF, which is regulated by the metalloproteinase MMP-9.

Immunosuppressive MDSCs induced by TLR signaling during infection and role in resolution of inflammation.

Ligand-mediated activation of toll-like receptors (TLRs) not only induces inflammation but also immune suppression, which is an emerging area of investigation. Multiple negative feedback intracellular mechanisms have been described that are brought into play to prevent uncontrolled TLR activation. However, the identification of TLR-induced regulatory myeloid cells is a relatively recent development that has ramifications in pathogen-induced disease state as well as in cancer.

Interleukin-12p40 modulates human metapneumovirus-induced pulmonary disease in an acute mouse model of infection.

The mechanisms that regulate the host immune response induced by human metapneumovirus (hMPV), a newly-recognized member of the Paramyxoviridae family, are largely unknown. Cytokines play an important role in modulating inflammatory responses during viral infections. IL-12p40, a known important mediator in limiting lung inflammation, is induced by hMPV and its production is sustained after the resolution phase of infection suggesting that this cytokine plays a role in the immune response against hMPV.

Neem leaf glycoprotein suppresses regulatory T cell mediated suppression of monocyte/macrophage functions.

We have shown that neem leaf glycoprotein (NLGP) inhibits the regulatory T cell (Tregs) induced suppression of tumoricidal functions of CD14(+)CD68(+) monocyte/macrophages (MO/Mφ) from human peripheral blood. Cytotoxic efficacy of MO/Mφ toward macrophage sensitive cells, U937, is decreased in presence of Tregs (induced), however, it was increased further by supplementation of NLGP in culture. Associated Treg mediated inhibition of perforin/granzyme B expression and nitric oxide release from MO/Mφ was normalized by NLGP.

Dysregulated CC receptor/ligand in monocytes/macrophages from tongue squamous cell carcinoma patients is partially rectified by interferon α-2b.

In an aim to rectify dysregulated CC chemokine receptor (CCR5)/ligand (RANTES, MIP-1α, MIP-1β) status of monocytes/macrophages in tongue squamous cell carcinoma (TSCC; n = 12) patients, we have tested interferon α2b (IFNα2b), a novel immunomodulator with wide use in the management of several forms of cancer. IFNα2b can upregulate reduced CCR5 expression and increases the suppressed secretory status of its ligands, as evidenced from in vitro studies on monocytes/macrophages from the peripheral blood of TSCC patients as well as healthy individuals. Isolated monocytes of TSCC patients (n = 5) undergoing chemotherapeutic treatment along with IFNα2b immunotherapy demonstrated significant upregulation in CCR5 expression and secretion of corresponding ligands.

Defective dendritic cell generation from monocytes is a potential reason for poor therapeutic efficacy of interferon α2b (IFNα2b) in cervical cancer.

Despite being a pleiotropic cytokine, the therapeutic potential of interferon α2b (IFNα2b) is debatable. Thus, the need for identifying predictive marker(s) for patients who are most likely to benefit from the treatment is pivotal for avoiding the exposure of nonresponsive patients to the toxicity of the treatment. To account for the attenuated efficacy of the drug, we have verified its dendritic cell (DC) maturating ability from monocytes of cervical cancer stage IIIB (CaCx-IIIB) patients.

Neem leaf glycoprotein inhibits CD4+CD25+Foxp3+ Tregs to restrict murine tumor growth.

Background: The presence of Tregs in tumors is associated with compromised tumor-specific immune responses and has a clear negative impact on survival of cancer patients. Thus, downregulation of Tregs is considered as a promising cancer immunotherapeutic approach. We have reported previously that neem leaf glycoprotein (NLGP) prophylaxis restricts tumor growth in mice by immune activation.

Cigarette smoke suppresses TLR-7 stimulation in response to virus infection in plasmacytoid dendritic cells.

Exposure to environmental tobacco smoke (ETS) is associated with an increase in the frequency and severity of respiratory infections, including bronchiolitis, a clinical syndrome of infancy caused by viruses such as respiratory syncytial virus (RSV). The mechanisms by which ETS increases the risk of viral respiratory infections are largely unknown. A major effector integrating early antiviral and immunostimulatory activities is interferon-α (IFN-α), which is highly produced by plasmacytoid dendritic cells (pDC).

Neem leaf glycoprotein partially rectifies suppressed dendritic cell functions and associated T cell efficacy in patients with stage IIIB cervical cancer.

Myeloid-derived dendritic cells (DCs) generated from monocytes obtained from stage IIIB cervical cancer (CaCx IIIB) patients show dysfunctional maturation; thus, antitumor T cell functions are dysregulated. In an objective to optimize these dysregulated immune functions, the present study is focused on the ability of neem leaf glycoprotein (NLGP), a nontoxic preparation of the neem leaf, to induce optimum maturation of dendritic cells from CaCx IIIB patients. In vitro NLGP treatment of immature DCs (iDCs) obtained from CaCx IIIB patients results in upregulated expression of various cell surface markers (CD40, CD83, CD80, CD86, and HLA-ABC), which indicates DC maturation.

An adhesion protein of Salmonella enterica serovar Typhi is required for pathogenesis and potential target for vaccine development.

More than half of all Salmonella enterica serovar Typhi genes still remain unannotated. Although pathogenesis of S. Typhi is incompletely understood, treatment of typhoid fever is complicated by the emergence of drug resistance.

Restoration of dysregulated CC chemokine signaling for monocyte/macrophage chemotaxis in head and neck squamous cell carcinoma patients by neem leaf glycoprotein maximizes tumor cell cytotoxicity.

Previous studies have shown that the CC chemokine receptor CCR5 is downregulated on monocyte/macrophage (MO/Mphi) surfaces in head and neck squamous cell carcinoma (HNSCC) patients (stage IIIB). Ligands (RANTES, MIP-1alpha and MIP-1beta) of this chemokine receptor were also secreted in lesser quantity from MO/Mphi of HNSCC patients in comparison with healthy individuals. In an aim to restore this dysregulated receptor-ligand signaling, we have used neem leaf glycoprotein (NLGP), a novel immunomodulator reported from our laboratory.