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Abstract The skin is the first anatomical region that dengue virus (DENV) encounters during the natural infection. Although the role of some skin resident cells like dendritic cells and fibroblasts has been demonstrated to be crucial to elucidate the role of resident cells and molecules participating during the early events of the innate immune response, the participation of keratinocytes during DENV infection has not been fully elucidated. In this paper we aimed to evaluate the use of the HaCaT cell line as a model to study the immune responses of skin keratinocytes to DENV infection. We demonstrated productive DENV-2 infection of HaCaT cells and their capability to establish an antiviral response through production of type I and type III interferons (IFN-β and IFN-λ). The production of these cytokines by HaCaT cells correlated with upregulation of IFN-inducible transmembrane protein-3 (IFITM3) and viperin in bystander, uninfected cells. We also observed an increase in secretion of IL-6 and IL-8. Skin keratinocytes are known to secrete antimicrobial peptides (AMPs) during viral infections. In our model, DENV-2 infected HaCaT cells upregulate the production of cytoplasmic LL-37. We evaluated the dual role of LL-37, HBD2, and HBD3 antiviral activity and immunoregulation during DENV-2 infection of HaCaT cells and found that LL-37 significantly reduced DENV-2 replication. This indicates that the HaCaT cell line can be used as a model for studying the innate response of keratinocytes to DENV infection. Our results also suggest that skin keratinocytes play an important role in the skin microenvironment after DENV infection by secreting molecules like type I and type III IFNs, pro-inflammatory molecules, and LL-37, which may contribute to the protection against arboviral infections. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the deadliest and most common type of primary brain tumor in adults with a grim prognosis despite multimodal treatments. Dendritic cell (DC)-based immunotherapy has emerged as a promising therapeutic modality for GBM, whose efficacy is nonetheless fundamentally undermined by GBM-induced immunosuppression. Inducing emission of damage associated molecular patterns (DAMPs) is a highly effective strategy to subvert tumor-associated immunosuppression. The present work was carried out to explore the idea of subverting the GBM immunosuppressive microenvironment through DC-mediated delivery of doxorubicin-polyglycerol-nanodiamond composites (Nano-DOX), a potent DAMPs inducer demonstrated by our previous study, and thereby eliciting enhanced DC-driven anti-GBM immune response. In the in-vitro work on human cell models, Nano-DOX-loaded DC were shown to be functionally viable and release cargo drug to co-cultured GBM cells (GC). Nano-DOX-treated GC displayed not only profuse DAMPs emission but also antigen release. Enhanced activation and acquisition and presentation of GC-derived antigen were then demonstrated in DC in co-culture with GC and Nano-DOX. Consistently, co-culture with GC and Nano-DOX also activated mouse bone marrow-derived DC (mDC) which in turn stimulated mouse spleen-derived lymphocytes which ultimately suppressed co-cultured GC. Next, athymic mice bearing orthotopic human GBM xenografts were intravenously injected with Nano-DOX-loaded mDC and, 48 h later, spleen-derived lymphocytes. The presence of Nano-DOX, DAMPs emission and enhanced infiltration and activation of mDC and lymphocytes were detected in the GBM xenografts. Taken together, our results demonstrate the efficacy of DC-mediated delivery of Nano-DOX to stimulate GC immunogenicity and elicit anti-cancer immune response in the GBM. By this work, we present a novel approach with great application potential to subverting the GBM immunosuppressive microenvironment and to anti-GBM immunotherapy. Investigation has also been conducted probing the mechanisms by which Nano-DOX stimulates GC immunogenicity, which is described in a follow-up paper. [ABSTRACT FROM AUTHOR]

Created with BioRender.com [Display omitted] Cancer immunity is dependent on dynamic interactions between T cells and dendritic cells (DCs). Polymer-based nanoparticles target DC receptors to improve anticancer immune responses. In this paper, DC surface receptors and their specific coupling natural ligands and antibodies are reviewed and compared. Moreover, reaction mechanisms are described, and the synergistic effects of immune adjuvants are demonstrated. Also, extracellular-targeting antigen-delivery strategies and intracellular stimulus responses are reviewed to promote the rational design of polymer delivery systems. [ABSTRACT FROM AUTHOR]

Summary The mononuclear phagocytic system (MPS), comprised of monocytes, macrophages, and dendritic cells, is essential in tissue homeostasis and in determining the balance of the immune response through its role in antigen presentation. It has been identified as a therapeutic target in infectious disease, cancer, autoimmune disease and transplant rejection. Here, we review the current understanding of the immunophenotype and function of the MPS in normal human liver. Using well-defined selection criteria, a search of MEDLINE and EMBASE databases identified 76 appropriate studies. The majority (n = 67) described Kupffer cells (KCs), although the definition of KC differs between sources, and little data were available regarding their function. Only 10 papers looked at liver dendritic cells (DCs), and largely confirmed the presence of the major dendritic cell subsets identified in human blood. Monocytes were thoroughly characterized in four studies that utilized flow cytometry and fluorescent microscopy and highlighted their prominent role in liver homeostasis and displayed subtle differences from circulating monocytes. There was some limited evidence that liver DCs are tolerogenic but neither liver dendritic cell subsets nor macrophages have been thoroughly characterized, using either multi-colour flow cytometry or multi-parameter fluorescence microscopy. The lobular distribution of different subsets of liver MPS cells was also poorly described, and the ability to distinguish between passenger leukocytes and tissue resident cells remains limited. It was apparent that further research, using modern immunological techniques, is now required to accurately characterize the cells of the MPS in human liver. [ABSTRACT FROM AUTHOR]

Abstract: B cells not only play a pivotal role in humoral immunity, but also are involved in a broad spectrum of immune responses, including antigen presentation and T-cell function regulation. The identification of cell-surface CD molecules derived from a series of Human Leukocyte Differentiation Antigens (HLDA) Workshops has been instrumental to the discovery and functional characterization of human B-cell populations. Moreover, many events regulating B-cell development, activation, and effector functions are orchestrated by these cell-surface molecules. During the Ninth HLDA Workshop (HLDA9) eighteen new CDs were allocated to cell-surface molecules expressed on B cells: CD210a (IL10RA), CD215 (IL15RA), CD270 (TNFRSF14), CD307a (FCRL1), CD307b (FCRL2), CD307c (FCRL3), CD307d (FCRL4), CD351 (FCAMR), CD352 (SLAMF6), CD353 (SLAMF8), CD354 (TREM1), CD355 (CRTAM), CD357 (TNFRSF18), CD358 (TNFRSF21), CD360 (IL21RA), CD361 (EVI2B), CD362 (SDC2), and CD363 (S1PR1). Here we present their expression patterns on leukocytes, including T lymphocytes, NK cells, granulocytes, monocytes, plasmacytoid and monocyte-derived dendritic cells, and several B-cell subsets. These new CD molecules are expressed on B cells at various stages of differentiation; from bone marrow precursor pro-B cells to plasma cells. Three of them, CD307a, CD307b and CD307d, exhibit a B-cell restricted expression pattern, whereas the rest are also present on other leukocytes. In this paper we also review the structural characteristics, expression, and function of these new CD molecules. The availability of monoclonal antibodies directed against novel B cell-surface molecules will have broad implications not only for B-cell biology, but also for the development of new diagnostic and therapeutic tools. [Copyright &y& Elsevier]

Abstract: In the present work, the capacity of new pro-GSH molecules to increase the intra-macrophage thiol content in vitro and in vivo as well as to shift the immune response to Th1 in ovalbumin (Ova)-sensitized mice were examined. The molecules were the N-butanoyl GSH derivative, GSH-C4, and a pro-drug of N-acetylcysteine (NAC) and beta-mercaptoethylamine (MEA), I-152. In vitro, 2h-incubation with both molecules was found to increase intra-macrophage thiol content; in vivo, Ova-sensitized mice pre-treated by intraperitoneal administration of the pro-GSH molecules showed an increase in plasma anti-Ova IgG2a and IgG2b, characterizing Th1 immune response, and a decrease in IgG1, typical of the Th2 response. Such findings were connected to a shift to a Th1 response also involving splenocyte IFN-γ production as revealed by ELISPOT assay and higher levels of IL-12 in circulation. Although immune responses are in vivo mediated both by dendritic cells and macrophages, the data reported in this paper corroborate the suggestion that the pro-GSH molecules, increasing the intra-cellular thiol pool, modulate the Th1/Th2 balance favouring Th1-type responses and may be employed as Th1-directing adjuvants in new vaccination protocols and as immunomodulators in those diseases where Th1 response patterns are compromised in favour of Th2. [ABSTRACT FROM AUTHOR]

Abstract: Dendritic cells (DCs) are bone marrow-derived professional antigen presenting cells. Due to their role as potent inducers of immune responses, these cells are widely used as adjuvant in experimental clinical settings for cancer immune therapy. We have developed a DC-based vaccine using autologous blood monocytes loaded with allogeneic tumor cell lysate rich in cancer/testis antigens. This vaccine has at present been tested for activity in three phase II clinical trials including two cohorts of patients with advanced colorectal cancer (CRC) and one cohort of patients with advanced non-small-cell-lung-cancer (NSCLC). In the present paper we retrospectively compare the maturation profile based on surface marker expression on DCs generated from the three patient cohorts and between cancer patient cohorts and a cohort of healthy donors. Vaccines were generated under cGMP conditions and phenotypic profiles of DC were analyzed by flow cytometry and the obtained data were used as a basis to set guideline values for our quality control of GMP produced DC vaccines. Each vaccine batch was analyzed for the expression of the surface maturation and differentiation molecules CD14, CD1a, CD83, CD86, MHC class II and CCR7, and the optimal expression pattern is considered as CD14low, CD1a, CD83high, CD86high, MHC class IIhigh and CCR7high. In accordance with data from other studies including other types of cancer patients, especially breast cancer patients, we found that the maturation status of the DC batches depends on cancer type and correlates with clinical status of cancer patients included. [Copyright &y& Elsevier]

Abstract: This paper provides a review of the role of dendritic cells (DC) in microparticle-mediated immune response and the advantages of associating DNA to microparticles in order to increase the potency of DNA vaccination in vivo. To begin with, different methods for the preparation of DNA-loaded microparticle with poly(lactide) (PLA)/poly(lactide-co-glycolide) (PLGA) polymers are presented. Further, the effects of DNA-loaded microparticles on DC in vitro are extensively examined including transfection and stimulation of DC, a key feature of the immune response. Finally, in vivo tracking of DNA-loaded microparticles and induction of immune responses upon DNA-loaded microparticle administration in different animal models and with various routes of administration are reviewed. [Copyright &y& Elsevier]