Revamping the corneal permeability and antiglaucoma therapeutic potential of brinzolamide using transniosomes: optimization, in vitro and preclinical evaluation.

Aim: This study aims to explore potential of transniosomes, a hybrid vesicular system, as ocular drug-delivery vehicle. Materials & methods: Thin-film hydration technique was used to fabricate brinzolamide-loaded transniosomes (BRZ-TN) and optimized using Box-Behnken design, further exhaustively characterized for physicochemical evaluations, deformability, drug release, permeation and preclinical evaluations for antiglaucoma activity. Results: The BRZ-TN showed ultradeformability (deformability index: 5.71), exhibiting sustained drug release without irritation (irritancy score: 0) and high permeability compared with the marketed formulation or free drug suspension. The extensive in vivo investigations affirmed effective targeted delivery of transniosomes, with brinzolamide reducing intraocular pressure potentially. Conclusion: Our findings anticipated that BRZ-TN is a promising therapeutic nanocarrier for effectively delivering cargo to targeted sites by crossing corneal barriers.

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Myeloid-derived suppressor cells impede T cell functionality and promote Th17 differentiation in oral squamous cell carcinoma.

Oral tumor microenvironment is characterized by chronic inflammation signified with infiltrating leukocytes and soluble mediators which cause immune suppression. However, how immunosuppressive cells like myeloid-derived suppressor cells (MDSCs) maintain the immunosuppressive tumor microenvironment and influence T cell function in oral squamous cell carcinoma (OSCC) patients remains poorly understood. In the present study, we found that percentages of MDSCs were higher in oral cancer patients compared to healthy individuals and correlated with cancer stage. Monocytic MDSCs (M-MDSCs) were prevalent in the periphery, while granulocytic/polymorphonuclear subset dominated the tumor compartment. M-MDSCs suppressed the lymphocyte proliferation and decreased the CD3-ζ (zeta) chain expression and interferon gamma production. The percentage of M-MDSCs in peripheral blood correlated inversely with CD3-ζ chain expression in T cells of these patients. Interleukin 6 (IL-6)-induced phosphorylated STAT3-regulated programmed cell death ligand 1, CCAAT/enhancer-binding proteins alpha and beta and Interleukin 10 expression in MDSCs. MDSCs inhibited TGF-ß-driven generation of induced regulatory T cells in vitro. M-MDSCs secreted interleukins IL-6, IL-1ß, IL-23 and PGE2 and facilitated T-helper 17 (Th17) cell differentiation which utilizes nitric oxide synthase and cyclooxygenase 2 enzyme activity. Interestingly, OSCC patients showed increased levels of Th17 cells in peripheral blood and tumor tissue. Thus, increased frequency of MDSCs, Th17 cells and decreased expression of CD3-ζ chain portray T cell tolerance and chronic inflammatory state facilitating tumor growth.

Low major adverse cardiac event rates following bioresorbable vascular scaffold implantation: Impact of implantation technique on treatment outcomes.

BACKGROUND AND OBJECTIVE: Studies conducted across the world have reported that the rates of major adverse cardiac events (MACE) following the use of bioresorbable vascular scaffolds (BVS) are comparable to that noted with traditional drug eluting stents (DES). However, there is limited data on the immediate and medium-term clinical outcomes following the use of the Absorb BVS (Abbott Vascular, Santa Clara, SA) in the Indian context. This study was conducted to determine real-world evidence on the immediate and medium-term clinical outcomes in all patients undergoing percutaneous coronary intervention (PCI) with the Absorb BVS. METHODS: Data of all patients who were treated with Absorb BVS at our center were evaluated. Between December 2012 and October 2016, 142 patients underwent PCI with BVS. The MACE rates during hospitalization, at 30days, 3 months, 6 months after PCI, and every 6 months thereafter were the primary endpoints evaluated with median follow up of 13 months. RESULTS: Mean age of the study participants was 53.7±11.8years. Intravascular ultrasound imaging was performed in 15.34% of patients. Predilatation and postdilatation were performed in 81.8% and 84.6% of scaffolds, respectively. There were no episodes of MACE during hospitalization. However, 1 BVS-related MACE was observed at the 1-month (0.7%) as well as at the ≥12 month (0.8%) follow up visits. At the 6- and 12-month follow up visits, 2 (1.5%) and 3 (2.5%) non-BVS-related MACEs, respectively, were recorded. CONCLUSION: The use of Absorb BVS in this real-world experience was associated with very good immediate and medium-term clinical outcomes.

IL17 producing γδT cells induce angiogenesis and are associated with poor survival in gallbladder cancer patients.

Despite conventional treatment modalities, gallbladder cancer (GBC) remains a highly lethal malignancy. Prognostic biomarkers and effective adjuvant immunotherapy for GBC are not available. In the recent past, immunotherapeutic approaches targeting tumor associated inflammation have gained importance but the mediators of inflammatory circuit remain unexplored in GBC patients. In the current prospective study, we investigated the role of IL17 producing TCRγδ(+) (Tγδ17), CD4(+) (Th17), CD8(+) (Tc17) and regulatory T cells (Tregs) in pathogenesis of GBC. Analysis by multi-color flow cytometry revealed that compared to healthy individuals (HI), Tγδ17, Th17 and Tc17 cells were increased in peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TIL) of GBC patients. Tregs were decreased in PBMCs but increased in TILs of GBC patients. The suppressive potential of Tregs from GBC patients and HI were comparable. Serum cytokines profile of GBC patients showed elevated levels of cytokines (IL6, IL23 and IL1ß) required for polarization and/or stabilization of IL17 producing cells. We demonstrated that Tγδ17 cells migrate toward tumor bed using CXCL9-CXCR3 axis. IL17 secreted by Tγδ17 induced productions of vascular endothelial growth factor and other angiogenesis related factors in GBC cells. Tγδ17 cells promote vasculogenesis as studied by chick chorioallantoic membrane assay. Survival analysis showed that Tγδ17, Th17 and Treg cells in peripheral blood were associated with poor survival of GBC patients. Our findings suggest that Tγδ17 is a protumorigenic subtype of γδT cells which induces angiogenesis. Tγδ17 may be considered as a predictive biomarker in GBC thus opening avenues for targeted therapies.

The Jekyll and Hyde story of IL17-Producing γδT Cells.

In comparison to conventional αßT cells, γδT cells are considered as specialized T cells based on their contributions in regulating immune response. γδT cells sense early environmental signals and initiate local immune-surveillance. The development of functional subtypes of γδT cells takes place in the thymus but they also exhibit plasticity in response to the activating signals and cytokines encountered in the extrathymic region. Thymic development of Tγδ1 requires strong TCR, CD27, and Skint-1 signals. However, differentiation of IL17-producing γδT cells (Tγδ17) is independent of Skint-1 or CD27 but requires notch signaling along with IL6 and TGFß cytokines in the presence of weak TCR signal. In response to cytokines like IL23, IL6, and IL1ß, Tγδ17 outshine Th17 cells for early activation and IL17 secretion. Despite expressing similar repertoire of lineage transcriptional factors, cytokines, and chemokine receptors, Tγδ17 cells differ from Th17 in spatial and temporal fashion. There are compelling reasons to consider significant role of Tγδ17 cells in regulating inflammation and thereby disease outcome. Tγδ17 cells regulate mobilization of innate immune cells and induce keratinocytes to secrete anti-microbial peptides thus exhibiting protective functions in anti-microbial immunity. In contrast, dysregulated Tγδ17 cells inhibit Treg cells, exacerbate autoimmunity, and are also known to support carcinogenesis by enhancing angiogenesis. The mechanism associated with this dual behavior of Tγδ17 is not clear. To exploit, Tγδ17 cells for beneficial use requires comprehensive analysis of their biology. Here, we summarize the current understanding on the characteristics, development, and functions of Tγδ17 cells in various pathological scenarios.

Insights into the Relationship between Toll Like Receptors and Gamma Delta T Cell Responses.

The tumor microenvironment is an important aspect of cancer biology that contributes to tumor initiation, tumor progression and responses to therapy. The composition and characteristics of the tumor microenvironment vary widely and are important in determining the anti-tumor immune response. Successful immunization requires activation of both innate and adaptive immunity. Generally, immune system is compromised in patients with cancer due to immune suppression, loss of tumor antigen expression and dysfunction of antigen presenting cells (APC). Thus, therapeutic immunization leading to cancer regression remains a significant challenge. Certain cells of the immune system, including dendritic cells (DCs) and gamma delta (γδ) T cells are capable of driving potent anti-tumor responses. The property of MHC-unrestricted cytotoxicity, high potential of cytokine release, tissue tropism and early activation in infections and malignant disease makes γδ T cells as an emerging candidate for immunotherapy. Various strategies are being developed to enhance anti-tumor immune responses of γδ T cells and DCs one of them is the use of novel adjuvants like toll like receptors (TLR) agonists, which enhance γδ T cell function directly or through DC activation, which has ability to prime γδ T cells. TLR agonists are being used clinically either alone or in combination with tumor antigens and has shown initial success in both enhancing immune responses and eliciting anti-tumor activity. TLR activated γδ T cells and DCs nurture each other's activation. This provides a potent base for first line of defense and manipulation of the adaptive response against pathogens and cancer. The available data provides a strong rationale for initiating combinatorial therapy for the treatment of diseases and this review will summarize the application of adjuvants (TLRs) for boosting immune response of γδ T cells to treat cancer and infectious diseases and their use in combinatorial therapy.