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Botta, D.

Publications and source records attributed to Botta, D..

6 recordsLinked to original sources

Intranasal immunization with live-attenuated RSV-vectored SARS-CoV-2 vaccines elicits antigen-specific systemic and mucosal immunity and protects against viral challenge and natural infection

The emergence of new SARS-CoV-2 variants and breakthrough infections underscores the need for next-generation vaccines capable of protecting from natural infection and/or preventing virus transmission to others. Intranasal vaccination offers a promising approach by eliciting local immune responses in the nasal mucosa, the primary site of infection and reservoir for transmissible virus. We evaluated two live-attenuated, respiratory syncytial virus vectored vaccines in which the RSV F and G surface glycoproteins were replaced with a chimeric SARS-CoV-2 Spike protein from either the ancestral USA/WA-1/2020 strain (MV-014-212) or the Delta variant (MV-014-212-delta). A single intranasal dose of either vaccine elicited systemic and mucosal immunity in K18-hACE2 mice, including serum neutralizing antibodies, Spike-specific memory B cells and plasmablasts, and Spike-specific CD8 lung-resident memory T cells. Although MV-014-212-delta vaccination provided the best protection against Delta variant virus challenge, both vaccines decreased viral loads in nasal discharge, lung and brain, and reduced weight loss and mortality. In naturally acquired infection studies, vaccinated hamsters exposed to infected cagemates exhibited minimal weight loss, limited viral replication within the nasal mucosa, and attenuated lung pathology. Therefore, intranasal RSV-vectored vaccines can elicit broad protective respiratory immunity, suggesting that this platform could be leveraged for other respiratory pathogens.

immunology↗

Mucosal delivery of influenza antigens using a replication deficient adenovirus supports broadly reactive antibody responses and heterologous viral immunity in the respiratory tract of animals

Systemically administered influenza vaccines provide strain-limited protection, while influenza infection of the respiratory epithelium supports development of lung resident memory B and T cells and more broadly reactive antibody responses. To test whether local antigen delivery is critical for establishing broad immunity, we directly compared respiratory tract and systemic delivery of influenza antigens to mice and hamsters using a replication-deficient adenovirus serotype 5 vector (Ad5[E1-,E2b-,E3-]). Both immunization routes elicited antibody responses in the lower respiratory tract and antigen-specific B and T cells in the draining lymph node. However, only intranasal immunization established lung-resident memory B and T cells, induced IgA responses in the upper respiratory tract directly at the site of viral entry and supported generation of IgA and IgG antibodies that bound antigenically drifted and distantly related influenza strains, including those of avian origin. Intranasal immunization accelerated viral clearance following heterologous virus challenge and was associated with limited pulmonary inflammation and fibrosis. Thus, intranasal immunization with the immunologically stealthy Ad5[E1-,E2b-,E3-] platform supports respiratory and systemic immunity to divergent influenza strains in the absence of overt lung immunopathology, suggesting that local antigen delivery may be key to development of more broadly protective "universal" flu vaccines.

immunology↗

Endothelial Histone Deacetylase 1 Activity Impairs Kidney Microvascular NO Signaling in Rats Fed a High Salt Diet

AimWe aimed to identify new mechanisms by which a high salt diet (HS) decreases NO production in kidney microvascular endothelial cells. Specifically, we hypothesized HS impairs NO signaling through a histone deacetylase 1 (HDAC1)-dependent mechanism. MethodsMale Sprague Dawley rats were fed normal salt diet (NS; 0.49% NaCl) or high salt diet (4% NaCl) for two weeks. NO signaling was assessed by measuring L-NAME induced vasoconstriction of the afferent arteriole using the blood perfused juxtamedullary nephron (JMN) preparation. In this preparation, kidneys were perfused with blood from a donor rat on a matching or different diet to that of the kidney donor. Kidney endothelial cells were isolated with magnetic activated cell sorting and HDAC1 activity was measured. ResultsWe found that HS impaired NO signaling in the afferent arteriole. This was restored by inhibition of HDAC1 with MS-275. Consistent with these findings, HDAC1 activity was increased in kidney endothelial cells. We further found the loss of NO to be dependent upon the diet of the blood donor rather than the diet of the kidney donor and the plasma from HS fed rats to be sufficient to induce dysfunction suggesting a humoral factor, we termed Plasma Derived Endothelial-dysfunction Mediator (PDEM), mediates the endothelial dysfunction. The antioxidants, PEG-SOD and PEG-catalase, as well as the NOS cofactor, tetrahydrobiopterin, restored NO signaling. ConclusionWe conclude that HS activates endothelial HDAC1 through PDEM leading to decreased NO signaling. This study provides novel insights into the molecular mechanisms by which a HS decreases renal microvascular endothelial NO signaling.

physiology↗

Spatial heterogeneity of glioblastoma cells reveals sensitivity to NAD+ depletion at tumor edge

Even after total resection of glioblastoma core lesions by surgery and aggressive post-surgical treatments, life-threatening tumors inevitably recur. A characteristic obstacle in effective treatment is high intratumoral heterogeneity, both longitudinally and spatially. Recurrence occurs predominantly at the brain parenchyma-tumor core interface, a region termed tumor edge. Given the difficulty of accessing it surgically, the composition of the tumor edge, harboring both cancerous and non-cancerous cells, remains largely unknown. Here, to identify phenotypic diversity among heterogeneous glioblastoma core and edge lesions, we uncovered the existence of three phenotypically-distinct clonal subpopulations within individual tumors from glioblastoma patients. Clones from the tumor core shared the same phenotype, exclusively generating tumor-core cells. In contrast, two distinct clonal subtypes were identified at the tumor edge: one generated only edge-lesion cells and the other expanded more broadly to establish both edge- and core-lesions. Using multiple xenograft experimental models in mouse brains, tumor edge development was found to require that both somatic and tumor cells express the NADase CD38, combinedly elevating glioblastoma malignancy. In vitro data suggested that intracellular NADase activity at the edge was provoked through intercellular communication between edge clones and normal astrocytes. Systemic treatment of tumor-bearing mice with 78c, a small-molecule CD38 inhibitor, attenuated the formation of glioblastoma edge lesions, suggesting its clinical potential to pharmacologically eliminate tumor-edge lesions. Collectively, these findings provide novel phenotypic and mechanistic insights into clonal heterogeneity within glioblastoma, particularly in the surgically unresectable, currently understudied tumor edge.

cancer biology↗

Single-dose intranasal administration of AdCOVID elicits systemic and mucosal immunity against SARS-CoV-2 in mice

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the urgent need for effective preventive vaccination to reduce burden and spread of severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) in humans. Intranasal vaccination is an attractive strategy to prevent COVID-19 as the nasal mucosa represents the first-line barrier to SARS-CoV-2 entry before viral spread to the lung. Although SARS-CoV-2 vaccine development is rapidly progressing, the current intramuscular vaccines are designed to elicit systemic immunity without conferring mucosal immunity. Here, we show that AdCOVID, an intranasal adenovirus type 5 (Ad5)-vectored vaccine encoding the receptor binding domain (RBD) of the SARS-CoV-2 spike protein, elicits a strong and focused immune response against RBD through the induction of mucosal IgA, serum neutralizing antibodies and CD4+ and CD8+ T cells with a Th1-like cytokine expression profile. Therefore, AdCOVID, which promotes concomitant systemic and local mucosal immunity, represents a promising COVID-19 vaccine candidate.

immunology↗

IFNγ induces epigenetic programming of human T-bethi B cells and promotes TLR7/8 and IL-21 induced differentiation

Although B cells expressing the IFN{gamma}R or the IFN{gamma}-inducible transcription factor T-bet drive autoimmunity in Systemic Lupus Erythematosus (SLE)-prone mouse models, the role for IFN{gamma} signaling in human antibody responses is unknown. We show that elevated levels of IFN{gamma} in SLE patients correlate with expansion of the T-bet expressing IgDnegCD27negCD11c+CXCR5neg (DN2) pre-antibody secreting cell (pre-ASC) subset. We demonstrate that naive B cells form T-bethi pre-ASCs following stimulation with either Th1 cells or with IFN{gamma}, IL-2, anti-Ig and TLR7/8 ligand and that IL-21 dependent ASC formation is significantly enhanced by IFN{gamma} or IFN{gamma}-producing T cells. IFN{gamma} promotes ASC development by synergizing with IL-2 and TLR7/8 ligands to induce genome-wide epigenetic reprogramming of B cells, which results in increased chromatin accessibility surrounding IRF4 and BLIMP1 binding motifs and epigenetic remodeling of IL21R and PRDM1 loci. Finally, we show that IFN{gamma} signals poise B cells to differentiate by increasing their responsiveness to IL-21.

immunology↗