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Antimicrobial peptides (AMPs) are phylogenetically ancient substances released by living organisms for self protection against a broad variety of microbes. Moreover, AMPs are endowed with immune modulatory activities, linking innate and adaptive immunity together. Lantibiotics are AMPs of bacterial origin currently investigated for the generation of a new class of anti-infective compounds, owing to the phenomenon of antibiotic resistance against a broad variety of bacteria. Also, plants and marine AMPs are screened as novel drugs against human pathogens. Human AMPs encompass defensins and cathelicidins produced by various cell types mostly at mucosal sites. Besides their antimicrobial activity, both AMPs have been shown to trigger either inflammatory or anti-inflammatory pathways. Food-derived AMPs are mostly represented by lactoferrin and lysozyme both present in secretions, e.g., milk, and appear to be very exploitable for the generation of functional foods. Finally, the role of natural products ingested with food or administered as supplements on induction and production of AMPs will be discussed.

BACKGROUND Allergy to Anisakis simplex (s.) is spreading due to the increased consumption of raw, smoked or marinated fish. In man, Anisakis s. can directly attack the gastrointestinal mucosa, provoking a parasitosis known as anisakiasis, or giving rise to the formation of IgE and, finally, inducing IgE-mediated reactions like urticaria, angioedema and anaphylactic shock. During recent years, a dietary approach to Anisakis s. infestation has also been addressed. METHODS A total of 620 patients with urticaria, angioedema, or both and a history of anaphylaxis following consumption of raw, smoked or marinated fish were recruited, evaluated for specific IgE levels to Anisakis s. and subjected to Skin Prick test. Following 18 month fish-free diet, patients were reevaluated at 6, 12 and 18 months, respectively. Patients undergoing diet were selected among those who had a clinical history with multiple accesses to first aid. RESULTS After 6-month fish-free diet, we recorded an improvement of symptoms and a remarkable reduction of specific IgE levels. The extension of the diet over 6 months in some cases resulted in a further reduction of specific IgE levels. CONCLUSION Data obtained confirm the importance of a fish-free diet in patients with severe symptoms since a new antigenic exposure coincides with a relapse of symptoms and increased IgE levels. This last point should be kept in mind and carefully evaluated in patients at risk for anaphylaxis or angioedema.

The in vitro ability of polyphenols, extracted from red grape, to modulate peripheral blood mononuclear cell responses has been evaluated in 20 obese (Ob) people. With regard to cytokine release in response to phorbol myristate acetate (PMA), levels of interleukin-2 (IL-2), interferon-γ(IFN-γ), IL-4, IL-10, and IL-17 were higher in the Ob than in healthy (H) subjects.Vice versa, IL-21 concentrations were detected only in H people but they were undetectable in the Ob counterpart. In general terms, levels of IL-1β, IL-6, IL-8, and tumor necrosis factor-αwere higher in Ob people when compared to H controls. On the other hand, polyphenols did not modify IFN-γ, IL-4, and IL-17 levels. However, an increase in IL-2 was observed in H individuals, whereas its levels were decreased in the Ob counterpart. Polyphenols significantly increased IL-10 release from H donors, whereas a trend to increase was observed in Ob people. In addition, polyphenols were able to significantly increase levels of H IL-21, while this was not the case in Ob people. Since IL-21 is an inducer of Th17 cells, it is likely that polyphenols may suppress the sources of this cytokineviaproduction of IL-10. Accordingly, polyphenols decreased IL-1βand IL-6 release in comparison to H controls.

Immune decline with ageing accounts for the increased risk of infections, inflammatory chronic disease, autoimmunity and cancer in humans. Both innate and adaptive immune functions are compromised in aged people and, therefore, attempts to correct these dysfunctions represent a major goal of modern medicine. In this review, special emphasis will be placed on the aged innate immunity with special reference to polymorphonuclear cell, monocyte/ macrophage, dendritic cell and natural killer cell functions. As potential modifiers of the impaired innate immunity, some principal nutraceuticals will be illustrated, such as micronutrients, pre-probiotics and polyphenols. In elderly, clinical trials with the above products are scanty, however, some encouraging effects on the recovery of innate immune cells have been reported. In addition, our own results obtained with symbiotics and polyphenols extracted from red wine or fermented grape marc suggest the potential ability of these substances to modulate the innate immune response in ageing, thus reducing the inflammaging which characterizes immune senescence.

The innate lymphoid cells (ILCs) have been grouped into three main categories: ILC1s [T helper (h)1-like cells], ILC2s (Th2-like cells) and ILC3s (Th17-like cells), respectively. In particular, ILC3s are responsible for the secretion of both interleukin (IL)-17 and IL-22, which play either protective (antimicrobial and repairing activities) or harmful (inflammation and tumor growth) roles into the host. Here, some putative interventional studies will be hypothesized, taking into account that activation of innate cell receptors, arylhydrocarbon receptor and gut microbiota, respectively, contribute to both differentiation and function of ILC3s. A series of biological and natural compounds may represent putative regulators of these cells in the gut. In this respect, the modulating effects of agonist and antagonists of Toll-like receptors and nucleotide binding oligomerization domain-like receptors, polyphenols and probiotics will be described in detail.

There is growing evidence that the prevalence of overweight/obesity is increasing in both developed and developing countries. Furthermore, complications of overweight/obesity occurring during childhood may influence the healthy status in adulthood. On these grounds, here we have enrolled 15 overweight/obese, 15 normal weight and 15 underweight children. A series of parameters, such as eating habits thanks to the Body Mass Index (BMI), Youth Healthy Eating Index (YHEI), activity and inactivity, salivary nitric oxide concentration (NO), were determined and correlated between them. In particular, correlations of BMI with YHEI, activity/inactivity, and correlations of salivary NO concentration with YHEI, BMI and activity/inactivity were evaluated. In overweight and obese subjects, a positive correlation between BMI, YHEI, inactivity and salivary NO concentrations was shown, while an inverse correlation was documented between BMI and activity in overweight/obese group. In normal weight and in underweight children, respectively, a positive correlation between lower BMI, YHEI, salivary NO concentration, and higher physical activity was observed.

Polyphenols contained in FGM from Negroamaro (N) and Koshu (K) Vitis vinifera have been shown to exhibit several immunomodulating activities. For instance, mice affected by experimental colitis when administered with K-FGM showed an attenuation of the inflammatory process. In murine asthma, K-FGM reduced IgE production and eosinophil number in bronchial alveolar lavage fluid. In vitro, both N- and K-FGM were able to induce T regulatory cells in terms of Foxp-3 molecule expression and release of interleukin-10. In another set of experiments both N- and K-FGM were able to balance rate of proliferation/apoptosis/necrosis of normal human peripheral lymphocytes, thus indicating the property of these compounds to maintain immune homeostatic mechanisms in the host. On the other hand, N- and K-FGM inhibited human basophil degranulation, thus, confirming our previous results obtained with rat basophilic leukemia cells. Finally, N- and K-FGM also decreased oxidative burst of human polymorphonuclear cells and monocytes.Taken together, these findings imply the potential clinical usefulness of FGM administration in inflammatory/allergic conditions, such as chronic asthma.

Human ageing is characterized by several abnormalities of both innate and adaptive immune responses, thus leading to an increased frequency of infectious, inflammatory, allergic and autoimmune diseases. In elderly patients, among allergic diseases, asthma is a very common pathological event which complicates the dysfunction of many systems. Among a variety of natural products used to modulate the altered immune response, polyphenols have been shown to exert antiinflammatory activities in both young and aged persons. Here, special emphasis will be given to the the immune-modulating effects of Leucoselect® Phytosome® (a dietary supplement enriched in the flavonoid epigallocatechin) administered to frail elderly patients. Leucoselect® Phytosome® was able to upregulate the T helper (Th)1 response [increase in serum concentrations of interleukin (IL)-2 and interferon-γ]. On the other hand, IL-4 serum levels, as an index of Th2 function, fluctuated within normal ranges. Quite interestingly, in this cohort of frail aged patients from South Italy the balance between inflammation (IL-17) and anti-inflammation (IL-10) was preserved, thus suggesting that the Mediterranean diet might have been involved in the observed effects. In conclusion, these data support the ability of Leucoselect® Phytosome® to induce up-regulation of Th1 responses in frail elderly patients which may be beneficial in those patients affected by chronic allergic disorders.

Parkinson disease (PD) and Alzheimer disease (AD) are neurodegenerative processes whose frequency is dramatically increasing in the western world. Both diseases share a common pathogenic denominator characterized by an exaggerated activation of the systemic and cerebral immune system, respectively. For instance, lipopolysaccharides in PD and amyloid beta in AD trigger microglia and astrocytes to release reactive oxygen species (ROS) and proinflammatory cytokines. Infiltrating peripheral T cells once activated in the central nervous system also contribute to the neurodegenerative process. Besides innovative biotherapy, nutraceuticals or functional foods are currently investigated for their neuroprotective activities. Especially, vitamin D and polyphenols, seem to be promising therapeutic tools for inhibiting ROS formation and arresting cytokine-mediated neuroinflammation in PD and AD.

The continuous antigenic triggering has greatly contributed to the evolution of the immune system and, therefore, animals have developed cells able to cope with a broad variety of microbial antigens and or their toxins, e.g., endotoxins. At the same time, intestinal commensals have evolved along with human progress and introduction of new foods, thus empowering both regional and systemic immune response. In this review, some important steps in the evolution of the immune system will be analyzed such as organization of lymphoid organs, formation of germinal centers, leukocyte attraction to tissue function of Toll like receptors and role of antimicrobial peptides. In particular, the major phylogenetic acquisitions of living organisms in the assessment of the immune machinery will be emphasized. Finally, fish will be taken into consideration as animal models of human diseases also in view of drug design strategies. Special attention will be focused on vaccinated salmon and zebrafish models.

The environmental impact as well as malnutrition are responsible for an increased incidence of inflammatory diseases with a consequential loss of immune homeostasis. Therefore, administration of nutraceuticals is aimed at reconstituting the immune balance in terms of the so-called immune nutrition. Among many known nutraceuticals, more recently, donkey's and goat's milks have been used as good alternatives to human and bovine milk in various clinical conditions such as allergy, atopy and inflammatory diseases. In fact, both milks possess immunomodulating capacities and release nitric oxide, a potent vasodilator endowed with anti-atherogenic properties. In this review, emphasis will be placed on the consumption of fermented milk and, in particular, on its ability to modulate the aged immune system, even including the intestinal mucosal immune response in elderly. Therefore, for their specific properties donkey's and goat's milk administration to aged people should be encouraged.

Farmed fish are exposed to a continuous antigenic pressure by microbial and environmental agents, which may lead to a condition of chronic inflammation. In view of the notion that polyphenols, largely contained in fruits and vegetables, are endowed with antioxidant and anti-inflammatory activities, farmed sea bass (Dicentrarchus labraxL.) have been administered with red grape polyphenol-enriched feed. Polyphenols were extracted from the seeds ofCanosinaNero di TroiaVitis viniferaand mixed with conventional feed at two different concentrations (100 and 200 mg/kg, resp.). Fish samples collected at days 223 and 273, respectively, were evaluated for intestinal and spleen cytokine release as well as for spleen macrophage (MØ) and melanomacrophage center (MMC) areas and distribution. Data will show that in treated fish decrease of intestinal interleukin- (IL-) 1βand IL-6 and increase of splenic interferon- (IFN-)γoccur. On the other hand, in the spleen reduction of MØ number seems to parallel increase in MMCs. Collectively, these data suggest that polyphenol-administered sea bass generate lower levels of intestinal proinflammatory cytokines, while producing larger amounts of spleen IFN-γ, as an expression of a robust and protective adaptive immune response. Increase of MMCs corroborates the evidence for a protective spleen response induced by feed enriched with polyphenols.

Childhood obesity is characterized by a low-grade inflammation status depending on the multicellular release of cytokines, adipokines, and reactive oxygen species. In particular, the imbalance between anti-inflammatory T regulatory cells and inflammatory T helper 17 cells seems to sustain such a phlogistic condition. Alterations of gut microbiota since childhood also contribute to the maintenance of inflammation. Therefore, besides preventive measures and caloric restrictions, dietary intake of natural products endowed with anti-oxidant and anti-inflammatory activities may represent a valid interventional approach for preventing and/or attenuating the pathological consequences of obesity. In this regard, the use of prebiotics, probiotics, polyphenols, polyunsaturated fatty acids, vitamins, and melatonin in human clinical trials will be described.

The balance between T helper (h)1 and Th2 responsiveness seems to represent a key event in the evolution of hepatitis C virus (HCV) infection. In particular, Th1 cytokines [interleukin (IL-2) and interferon (IFN-γ)] have been demonstrated to mediate the antiviral immune response. Serum levels of Th1 cytokines (IL-2 and IFN-γ) as well as of Th2 products (IL-4 and IL-10) were determined in a group of HCV-positive patients before and after treatment with IFN-α and Ribavirin (RIB). Results indicate that responder patients exhibited increased levels of IFN-γ and IL-10, while this enhancement was not observed in non-responder patients. In this respect, the major effect exerted by the combined therapy with IFN-α / RIB could be represented by the attainment of a re-equilibrium between inflammatory (Th1) and antiinflammatory (Th2) mechanisms. In this framework, according to current literature, novel therapeutical approaches to treat HCV infection are represented by administration of recombinant IL-2 and IL-10.

Human peripheral blood mononuclear cells (PBMCs) were treated with Helicobacter pylori (Hp) organisms alone or with Hp-stimulated AGS cells (a gastric adenocarcinoma cell line). Hp organisms were able per se to increase the percentage of CD8 +/- CD95 +/- cells, while number of CD25+ cells and HLA-DR molecule expression increased following pretreatment with Hp-stimulated AGS cells. A comparison was made with a test system in which PBMCs were stimulated with Escherichia coli (Ec) organisms and colo-cells (a colon carcinoma cell line). In this case, CD95+ cells and CD25+ cells increased when the combination Ec organisms/colo-cells was present in the culture. On the other hand, Hp bacteria in combination with colo-cells were not able to induce activation and/or apoptotic surface markers on PBMCs, while Ec-stimulated AGS cells increased the expression of CD95 on PBMC. Finally, the direct interaction of AGS cells with Hp was able to induce higher expression of CD95 on gastric epithelial cells than Hp-stimulated PBMCs. Taken together, these data support the interplay between bacteria and epithelial cells in the course of Hp-mediated gastropathy.

Ulcerative colitis (UC) and Crohn's disease (CD) [inflammatory bowel disease (IBD)] are both characterized by an exaggerated immune response at the gut associated lymphoreticular tissue level. Such an abnormal and dysregulated immune response may be directed against luminal and/or enteric bacterial antigens, as also supported by murine models of inflammatory bowel disease (IBD) caused by organisms such as Citrobacter rodentium and Helicobacter hepaticus.Bacterial endotoxins or lipopolysaccharides (LPS) have been detected in the plasma of IBD patients and an abnormal microflora and/or an increased permeability of the intestinal mucosa have been invoked as cofactors responsible for endotoxemia. At the same time, the evidence that phagocytosis and killing exerted by polymorphonuclear cells and monocytes and the T-cell dependent antibacterial activity are decreased in IBD patients may also explain the origin of LPS in these diseases.In IBD, pro-inflammatory cytokines and chemokines have been detected in elevated amounts in mucosal tissue and/or in peripheral blood, thus suggesting a monocyte/macrophage stimulation by enteric bacteria and/or their constituents ( e.g. LPS).On these grounds, in experimental models and in human IBD, anti-cytokine monoclonal antibodies and interleukin receptor antagonists are under investigation for their capacity to neutralize the noxious effects of immune mediators. Finally, the administration of lactobacilli is beneficial in human IBD and, in murine colitis, this treatment leads to a normalization of intestinal flora, reducing the number of colonic mucosal adherent and translocated bacteria.

Atherosclerosis is an inflammatory disease characterized by lipid accumulation as well as vascular injury due to a massive infiltration of immune cells in the endothelial wall. Microbial and self- antigens are responsible for a persistent activation of immune and non-immune cells, thus leading to a condition of arterial chronic inflammation with plaque formation and rupture in complicated cases. In particular, the effects of bacteria, viruses and their toxic products as well as of glycated lipoproteins will be illustrated with special reference to the main inflammatory pathways triggered by a persistent antigenic load in the host. Taking into consideration this broad variety of antigens implicated in the pathogenesis of atherosclerosis, therapeutic approaches such as antibiotics, dietary intervention and immune therapies will be discussed.

Hashimoto's thyroiditis, the most common form of autoimmune thyroid disease, is characterised by lymphocytic infiltration of the thyroid gland, gradual destruction of the organ and production of thyroid specific auto antibodies (antithyroid peroxidase and antithyroglobulin antibodies). There are evidences that cast doubt on the pathogenetic role of these antibodies in thyroid autoimmunity. It is very likely that cellular destruction is mediated by other cellular mechanisms, such as auto reactive T-lymphocytes, natural killer and cytokines. However, other studies performed in animal models have led to the conclusion that organ specific autoimmune thyroiditis should be regarded as a polygenic disease with a penetrance that is strongly influenced by environmental factors. According to our recent results, patients affected by autoimmune thyroiditis exhibited a decreased percentage of NK and CD25 + bearing cells significantly in comparison to normal controls. Altogether these data indicated that in the patients with autoimmune thyroid disease a certain degree of peripheral immune deficiency was present.