The Proinflammatory Interleukin-21 Elicits Anti-Tumor Response and Mediates Autoimmunity

Localization and Activity of iNOS in Normal Human Lung Tissue and Lung Cancer Tissue

Inducible nitric oxide synthase (iNOS) is one of three enzymes generating nitric oxide (NO) from the amino acid L-arginine. iNOS-derived NO plays an important role in several physiological and pathophysiological conditions. NO is a free radical which produces many reactive intermediates that account for its bioactivity. In the human lung, the alveolar macrophage is an important producer of cytokines and this production may be modified by NO. Moreover, high concentrations of NO have been shown to increase nuclear factor KB (NF-kB) activation. Recent investigations of NO expression in tumor tissue indicated that, at least for certain tumors, NO may mediate one or more roles during the growth of human cancer. We have studied iNOS in two tissue groups: normal human lung tissue and human lung cancer tissue. We localized iNOS in these tissues by immunohistochemistry and tested the mRNA expression by RT-PCR, the protein level by Western blot, and the protein activity by radiometric analysis. The results demonstrate different expression, localization and activity of iNOS in normal versus tumor tissue. This is suggestive of a role for NO production from iNOS in human lung cancer because high concentrations of this short molecule may transform to highly reactive compounds such as peroxynitrite (ONOO-); moreover, through the upregulator NF-kB, they can induce a chronic inflammatory state representing an elevated risk for cell transformation to cancer.

Involvement of NK Cells against Tumors and Parasites

Host resistance against pathogens depends on a complex interplay of innate and adaptive immune mechanisms. Acting as an early line of defence, the immune system includes activation of neutrophils, tissue macrophages, monocytes, dendritic cells, eosinophils and natural killer (NK) cells. NK cells are lymphoid cells that can be activated without previous stimulation and are therefore like macrophages in the first line of defence against tumor cells and a diverse range of pathogens. NK cells mediate significant activity and produce high levels of proinflammatory cytokines in response to infection. Their cytotoxicity production is induced principally by monocyte-, macrophage- and dendritic cell-derived cytokines, but their activation is also believed to be cytokine-mediated. Recognition of infection by NK cells is accomplished by numerous activating and inhibitory receptors on the NK cells’ surface that selectively trigger the cytolytic activity in a major histocompability complex-independent manner. NK cells have trypanocidal activity of fibroblast cells and mediate direct destruction of extracellular epimastigote and trypomastigote forms of T. cruzi and T. lewisi in vitro; moreover, they kill plasmodia-infected erythrocytes directly through cell-cell interaction. This review provides a more detailed analysis of how NK cells recognize and respond to parasites and how they mediate cytotoxicity against tumor cells. Also the unique role of NK cells in innate immunity to infection and the relationship between parasites and carcinogenesis are discussed.

The Efficacy of Four Ways of Administrating Dexamethasone during Surgical Extraction of Partially Impacted Lower Third Molars

Glucocorticoids are drugs noted for their potent anti-inflammatory effect and long lasting half-life. Various studies have been carried out to identify which of these molecules is best for reducing the post-operative sequelae after surgical extraction of the impacted lower third molar. This study examines four different ways of administering dexamethasone after surgical extraction of impacted lower third molars: endoalveolar application, submucous injection, intravenous administration and intramuscular injection, with the aim of identifying which method gives the least discomfort to the patient in regard to reduction of pain, edema and post-operative lock-jaw. Results show that a greater reduction of the post-operative sequelae was obtained in the group of patients treated with dexamethasone intravenously. Satisfying results were also obtained in the group treated with a topical administration of dexamethasone in powder form and in the group which was given dexamethasone through an intramuscular injection. These last two groups had similar results. Instead, the results obtained in the group that received dexamethasone through local submucous injection were not satisfactory.

Microbiological Aspects and Inflammatory Response of Pulp Tissue in Traumatic Dental Lesions

Traumatic dental lesions are more frequently found in the pediatric population, with a major involvement, in 80% of the cases, of the superior central incisors. The exposure of the dental pulp leads to major morphological changes in dental tissue, such as discolouring, acute pulp inflammation, chronic inflammation and necrosis. This article reviews the various studies published on the different types of inflammatory response of the pulp tissue following traumatic events, from the microbiological and histological point of view of various techniques.

Tannic Acid Induces in vitro Acantholysis of Keratinocytes via IL-1α and TNF-α

The mechanism of acantholysis in pemphigus vulgaris (PV) is an intriguing argument since several chemical mediators are implicated. We previously reported a central role for IL-1α and TNF-α, both able to regulate complement activation and plasminogen activators. Very little is known about what triggers the disease (drugs, viruses or food). In this study, we evaluate the molecular role of tannins in acantholysis. By HPLC chromatography we measured tannic acid (TA) and gallic acid (GA) in blister fluid of 4 groups of patients divided according to their dietary habits, including a regular diet, a diet rich in tannins, a diet free of tannins, and a group of pemphigus patients. Blister fluid was obtained from patients using a suction blister apparatus. We show that people with a diet rich in tannins have increased tannin metabolites (TA and GA) in the skin in respect to controls (tannin-rich diet: GA = 194.52±2.39 nmol/ml; TA = 348.28±1.4 nmol/ml versus tannin-Mediterranean diet: GA = 15.28±1.63 nmol/ml; TA = 22.81±1.68 nmol/ml). PV patients showed similar values to the Mediterranean diet population (PV patients: GA = 95.8±1.97 nmol/ml; TA = 199.09±4.15 nmol/ml versus Mediterranean diet: GA = 83.53±2.35 nmol/ml; TA = 195.1±2.50 nmol/ml). In an in vitro acantholysis system using TA and PV-IgG we show that TA 0.1 mM in NHEK culture is able to induce acantholysis. This effect was able to amplify the acantholytic action of PV-IgG in vitro. A blocking study using anti IL-1α and anti TNF-α antibodies showed a reduction in TA-induced acantholysis. Taken together, these results suggest that a diet rich in tannins could be a trigger in genetically predisposed patients. If these data are confirmed, a complementary diet poor in tannins may be useful in patients affected by PV.

Expression of Co-stimulatory molecules on langerhans cells in lesional epidermis of human atopic dermatitis

Langerhans cells (LC) are immature dendritic cells (DC) present in the skin epithelium. To understand the molecular and cellular mechanisms governing the inflammatory reaction in atopic dermatitis (AD), the expression of the LC specific marker CD1a, a member of major histocompatibility (MHC)-like glycoproteins, and the co-stimulatory molecules CD80 and CD86, expressed on functionally mature dendritic cells, were counted in lesional biopsies and normal epidermis by an immunohistochemical method. CD1a specific staining was observed in both normal and AD lesion specimens. CD80 and CD86 positive cells with morphological characteristics of the LC were found in lesional AD epidermis, suggesting a high level of functional maturity of these cells and their involvement in chronic inflammatory disease.

Molecular classification of nodal metastasis in primary larynx squamous cell carcinoma

Classification and prognosis of larynx squamous cell carcinoma (LSCC) depends on clinical and histopathological examination. Currently, expression profiling harbors the potential to investigate, classify, and better manage cancer. Gene expression profiles of 22 primary LSCCs were analyzed by microarrays containing 19,200 cDNAs. GOAL functionally classified differentially expressed genes, and a novel "in silico" procedure identified physical gene clusters differentially transcribed. A signature of 158 genes differentiated tumors with nodal metastasis. A novel statistical method allowed categorization of metastatic tumors into 2 distinct subgroups of differential gene expression patterns. Among genes correlated to nodal metastatic progression, we verified in vitro that NM23-H3 reduced cell motility and TRIM8 were a growth suppressor. Six chromosomal regions were specifically downregulated in metastatic tumors. This large-scale gene expression analysis in LSCC provides information on changes in genomic activity associated with lymphonodal metastasis and identifies molecules that might prove useful as novel therapeutic targets.

Hypertonic Saline Solution in Children with Adenoidal Hyperytrophy: Preliminary Evidence

Adenoidal hypertrophy (AH) is a frequent problem in children. A preliminary study evidenced that intranasal hypertonic solutions may exert an anti-inflammatory activity. The aim of the study is to evaluate the effect of intranasal hypertonic or isotonic solutions in children affected with AH. For this purpose, 78 children with AH were evaluated in a randomised and controlled study. Inclusion criteria for the study required that each patient had to have a III or IV degree of AH on the initial endoscopic examination. Children were treated with intranasal hypertonic or isotonic saline solution for 8 weeks. After treatment, endoscopy was performed to evaluate AH degree. Hypertonic treatment was associated with significant (p<0.05) reduction of AH degree. There was a consistent reduction of children with III degree of AH. No adverse events were reported. This preliminary study demonstrates that an 8-week treatment with intranasal hypertonic solution is associated with significant reduction of AH. Therefore, this study evidences that hypertonic solution may exert an anti-inflammatory activity and is safe.

Expression and secretion of CXCL8 (IL-8), release of tryptase and transcription of histidine decarboxylase mRNA by anti-IgE-activated human umbilical cord blood-derived cultured mast cells

Activation of cytokine receptors and alterations in cytokines are thought to play important roles in neuronal dysfunction and in the pathogenesis of the nervous system diseases. CXCL8 (IL-8) is a CXC chemokine with chemotactic and inflammatory properties. Chemokines control mast cell infiltration in several inflammatory diseases, including stress and neurological dysfunctions. Using isolated human umbilical cord blood-derived cultured mast cells (HUCMC) from hematopoietic stem cells CD34+, mast cells were immunologically activated with anti-IgE at concentrations of 1, 5, 10 and 20 microg/ml leading to the dose-dependent production of IL-8 (p < 0.05). The increase in IL-8 mRNA expression was also noted when the cells were treated with anti-IgE at 10 microg/ml for 6 h. Immunologically activated HUCMC provoked the generation of tryptase in a dose- and time-dependent manner. We also found increased histidine decarboxylase (HDC) expression in activated HUCMC after 6 h of incubation, a rate-limiting enzyme responsible for the generation of histamine from histidine. Taken together, these results confirm that anti-IgE-activated mast cells release inflammatory mediators including CXCL8, a CXC chemokine which regulates several biological effects of mast cells, e.g. chemoattraction, and possibly causes cell arrest.

Anti-chemokine therapy for inflammatory diseases

Chemokines are inflammatory proteins acting via G-protein coupled chemokine receptors that trigger different signaling pathways. Monocyte chemoattractant protein-1 (CCL2/MCP-1) and regulated on activation, normal T expressed and secreted (CCL5/RANTES) are the two major members of the CC chemokine beta subfamily. The roles of RANTES and MCP-1 are emerging in regulating the recruitment of inflammatory cells into tissue during inflammation. The inhibition of MCP-1 and RANTES with corresponding antibodies or other inhibitors may provide benefits in different clinical scenarios including cancer, inflammation, CNS disorders, parasitic disease, autoimmune and heart diseases. RANTES and MCP-1 may represent targets for diagnostic procedures and therapeutic intervention, and may be useful as a prognostic factor in the above diseases.

In vitro stem cell cultures from human dental pulp and periodontal ligament: new prospects in dentistry

In spite of the vast knowledge of tooth development and of the various kinds of specialized bone/tooth-associated cells, the characteristics and properties of their precursor cell populations present in the postnatal organism are little known, as is their possible therapeutic use. Taken together dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) possess stem-cell-like qualities, including self-renewal capability and multi-lineage differentiation. Regenerative medicine is based on stem cells, signals and scaffolds. Transplantation of those cells, which can be obtained from an easily accessible tissue resource and expanded in vitro, holds promise as a therapeutic approach for reconstruction of tissues and bone in vivo.

Inhibitory effect of quercetin on tryptase and MCP-1 chemokine release, and histidine decarboxylase mRNA transcription by human mast cell-1 cell line

Mast cells are important in reactions of allergic disease and are also involved in a variety of neuroinflammatory diseases. Mast cells can be immunologically activated by IgE through their Fc receptors, as well as by neuropeptides and cytokines to secrete mediators. Here we used a human mast cell-1 (HMC-1) cell line cultured and treated with a physiological activator, anti-IgE, and a nonphysiological activator, calcium ionophore A23187, for tryptase and MCP-1 generation and transcription of histidine decarboxylase. We used quercetin, a potent antioxidant, cytoprotective and anti-inflammatory compound capable of inhibiting histamine and some cytokines released from several cell types, as an inhibitor of immunological and nonimmunological stimulus for mast cells. In this study quercetin inhibits, in a dose-response manner, tryptase and MCP-1. Moreover, using RT-PCR quercetin inhibited the transcription of histidine decarboxylase, the rate-limiting enzyme responsible for the generation of histamine from histidine, and MCP-1. Our data suggest that quercetin is an important and good candidate for reducing the release of pro-inflammatory mast cell mediators activated by physiological and nonphysiological stimulators.