Growth factors and IL-17 in hereditary angioedema.

Hereditary angioedema (HAE) is a rare autosomal dominant disorder, due to C1-inhibitor deficiency, which causes episodic swellings of subcutaneous tissues, bowel walls and upper airways which are disabling and potentially life-threatening. We evaluated n = 17 patients with confirmed HAE diagnosis in basal and crisis state and n = 19 healthy subjects. The samples were tested for IL-17, FGFb, G-CSF and GM-CSF, using Bio-plex kit. Data analysis was performed via nonparametric Spearman's correlations and two sets of linear mixed models. When comparing HAE subjects during basal and crisis states, we found out significantly (i.e., p value <0.05) higher values in crisis states rather than in basal states for the three growth factors and cytokine IL-17. When comparing healthy subjects versus HAE patients at basal state, we found out significantly higher values in HAE subjects only for GM-CSF, FGFb and IL-17, but not for G-CSF. In HAE patients, there is a connection between IL-17 and growth factors. The low-grade inflammation in absence of attacks is demonstrated by constant higher amount of IL-17, FGFb and GM-CSF with respect to healthy patients. This could indicate that in this disease there is a level of activation that maintains the system in a "tick-over state," that can be activate by several stimuli that are able to induce a increase in inflammatory mediators during the acute attack.

B cells compartment in centenarian offspring and old people.

Immunosenescence is considered a major contributory factor to the increased frequency of morbidity and mortality among elderly. On the other hand centenarians are considered the best example of successful ageing. To gain insight into mechanisms of immunosenescence and its clinical relevance, a possible model is represented by centenarians and/or their offspring. Nowadays centenarians are not more a curiosity, but in Europe are 1/8000 inhabitants and it has been demonstrated that the centenarian offspring, who are typically in their 70s and 80s, have a survival advantage when compared with age-matched controls whose parents died at an average life expectancy. Then again, studies on immunosenescence focus mainly on T cell impairment, although B cells are also affected. So, in the present preliminary report, we have studied B cell compartment in two classes of individuals, old people and centenarian offspring. B cell compartment was analysed using IgD and CD27 antibodies which characterize naïve B cells (IgD(+) CD27(-)), memory unswitched B cells (IgD(+)CD27(+)), memory switched B cells(IgD(-)CD27(+)) and double negative B cells (DN) (IgD(-)CD27(-)), i.e. exhausted memory cells. As expected, in both cohorts we observed a decreased B cell count. However, in centenarian offspring, naïve B cells are more abundant whereas exhausted memory cells (DN B cells, IgD(-)CD27(-)) do not show the increase that we have previously demonstrated in healthy elderly donors. These data are similar to that found in previously experiments on young subjects. So, our preliminary results show that centenarian offspring do not have the typical trend of memory/naive B cell subsets observed in elderly people and this is in agreement with the higher levels of IgM in the serum of centenarian offspring in comparison with data obtained in age-matched controls. This reservoir of naive B cell might be one of the causes that make centenarian offspring able to keep fighting off new infections, hence prolonging their life. So, B cell subset changes could represent a hallmark of successful or unsuccessful ageing and could be used as a biomarker of human life span, potentially useful for the evaluation of anti-ageing treatment.

Age-related inflammation: the contribution of different organs, tissues and systems. How to face it for therapeutic approaches.

A typical feature of ageing is a chronic, low-grade inflammation characterized by a general increase in the production of pro-inflammatory cytokines and inflammatory markers ("inflamm-ageing"). This status may slowly damage one or several organs, especially when unfavorable genetic polymorphisms and epigenetic alterations are concomitant, leading to an increased risk of frailty together with the onset of age-related chronic diseases. The contribution of different tissues (adipose tissue, muscle), organs (brain, liver), immune system and ecosystems (gut microbiota) to age-related inflammation ("inflamm-ageing") will be discussed in this review in the context of its onset/progression leading to site-restricted and systemic effects. Moreover, some of the possible strategies and therapies to counteract the different sources of molecular mediators which lead to the age-related inflammatory phenotype will be presented.

Immune-inflammatory responses and oxidative stress in Alzheimer's disease: therapeutic implications.

Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease which in Western society mainly accounts for clinical dementia. AD has been linked to inflammation and oxidative stress. Neuro-pathological hallmarks are senile plaques, resulting from the accumulation of several proteins and an inflammatory reaction around deposits of amyloid, a fibrillar protein, Abeta, product of cleavage of a much larger protein, the beta-amyloid precursor protein (APP) and neurofibrillary tangles. Inflammation clearly occurs in pathologically vulnerable regions of AD and several inflammatory factors influencing AD development, i.e. environmental factors (pro-inflammatory phenotype) and/or genetic factors (pro-inflammatory genotype) have been described. Irrespective of the source and mechanisms that lead to the generation of reactive oxygen species, mammalian cells have developed highly regulated inducible defence systems, whose cytoprotective functions are essential in terms of cell survival. When appropriately activated, each one of these systems has the possibility to restore cellular homeostasis and rebalance redox equilibrium. Increasing evidence, support the notion that reduction of cellular expression and activity of antioxidant proteins and consequent augment of oxidative stress are fundamental causes for ageing processes and neurodegenerative diseases., including AD. The better understanding of different molecular and cellular inflammatory mechanisms is crucial for complete knowledge of AD pathophysiology, hence for its prevention and drug therapy. Accordingly, two lines of preventive therapeutics can be outlined, the first based on anti-inflammatory drugs, the second one on anti-oxidative properties.

A pilot study on prostate cancer risk and pro-inflammatory genotypes: pathophysiology and therapeutic implications.

Host genetic factors are crucial risk determinants for many human cancers. In this framework, an interesting model is represented by prostate cancer (PC), which is featured by a complex pathophysiology with a strong genetic component. Multiple genes seem to influence PC risk and several single nucleotide polymorphisms (SNPs) of candidate genes modifying PC susceptibility have been identified. It is noteworthy the potential association of common SNPs in pro-inflammatory genes with PC risk, since chronic inflammation is assumed to play a key role in prostate carcinogenesis. With the aim to identify candidate genes as an experimental basis to develop new strategies for both prevention and treatment of PC, we have investigated the potential role of common SNPs of a gene cluster (TLR4, TLR2, PTGS2 and 5-Lo), involved in innate and inflammatory response, in PC cases, age-matched controls and centenarians from Sicily. Six SNPs were genotyped and their association with PC risk determined. Statistical analysis evidenced a significant association of some pro-inflammatory gene SNPs with an increased risk of PC. Furthermore, significant differences were observed comparing the three groups in the combined presence of a "high responder" pro-inflammatory profile. Overall, the present results suggest the likely association of these SNPs and PC risk, clearly motivating the need of larger studies to confirm the role of these genes in PC development and/or progression.

Role of TLR4 receptor polymorphisms in Boutonneuse fever.

The genetics of the interaction between host and microbes plays an essential role in the survival of the individual and attainment of longevity. The activation of toll-like receptor (TLR)4 plays a key role in natural and clonotypic immune responses. We evaluated whether TLR4 genotype is a component of genetic background protective versus rickettsiosis and whether this background influences longevity. We genotyped for +896A/G TLR4 polymorphism 78 patients affected with Boutonneuse fever, 78 age-matched controls and 78 advanced age individuals from Sicily. The +869G allele, that attenuates receptor signalling, was significantly overrepresented in patients in comparison with age-matched controls. By analyzing data according to gender, this allele was significantly higher in female patients when compared to advanced age women. Pro-inflammatory responses are programmed to resist fatal infections. So, it is not surprising that the genetic background of people that survive to an advanced age may be protective against infections. However, this seems to occur in women but not in men. In a previous study, the +896G TLR4 allele was overrepresented in advanced age men and underrepresented in men affected by myocardial infarction. Thus, previous and present results tend to agree with the suggestion that men and women may follow different trajectories to reach longevity. For men it might be more important to control atherogenesis, whereas for women it might be more important to control infectious diseases.

Association between platelet endothelial cellular adhesion molecule 1 (PECAM-1/CD31) polymorphisms and acute myocardial infarction: a study in patients from Sicily.

Adhesion of circulating cells to the arterial surface is among the first detectable events in atherogenesis. Cellular adhesion molecules, expressed by the vascular endothelium and by circulating leucocytes, mediate cell recruitment and their transendothelial migration. Platelet endothelial cellular adhesion molecule 1 (PECAM-1/CD31), involved in this migration, has been associated with the developmental course of atherosclerosis. A few studies have investigated an association between coronary heart disease and single nucleotide polymorphisms (SNPs) located in functionally important domains of the PECAM-1/CD31 gene. In particular, Ser563Asn and Gly670Arg SNPs have been described as susceptibility factors involved in acute myocardial infarction (AMI) in the Japanese male population. To confirm these observations, we studied 96 male patients (mean age 40 years; age range 20-46) affected by AMI and 118 healthy male controls (mean age 38 years, age range: 20-55), and analysed for the following PECAM-1/CD31 SNPs: Val125Leu, Asn563Ser and Gly670Arg. The frequency of the Gly670Arg polymorphism was significantly higher in patients with AMI (58.9% vs. 48.3%; P = 0.019), whereas the frequencies of the other two SNPs (Leu125Val and Ser563Asn) were not significantly different between patients and controls. By comparing the observed number of 670Arg/Arg genotypes in the patients with the expected number, calculated from the allele frequency in a healthy population, a significance of P = 0.02 (odds ratio, 2.04; 95% CI: 1.1-3.7) was obtained, supporting a recessive model of inheritance. Hence, the differences between patients and controls are significant, but relatively small. However, as AMI is a multifactorial disease, any single mutation will only provide a small or modest contribution to the risk, which also depends on environmental interaction. All in all, we believe that the results of the present study would add support to the role of pro/anti-inflammatory genotypes in determining susceptibility or resistance to immune-inflammatory diseases, including atherosclerosis.

Interleukin-10 promoter polymorphism in sporadic Alzheimer's disease.

Proinflammatory cytokines and acute-phase proteins play an important role in Alzheimer's disease (AD) neurodegeneration, and common polymorphisms of genes controlling their high production have been shown to be associated with AD. Thus, AD patients display a proinflammatory genotype and the control of inflammation might play a protective role in AD development. By sequence-specific probes, we have evaluated the role of anti-inflammatory cytokine interleukin(IL)-10 in AD, by analysing in 132 AD patients and 213 healthy controls the prevalence of three different haplotypes, involving three single-nucleotide polymorphisms (SNPs) at -1082 (G-->A), -819 (C-->T) and -592 (C-->A) nucleotides of IL-10 promoter, associated with different IL-10 production. The percentage of -1082A carrier subjects was significantly increased among AD patients, and this increase was mainly due to the increase of ATA haplotype. Analysing these results according to the well-known genetic risk factor APOE-e4 allele, no significant differences were observed in SNP IL-10 allele distribution between AD patients carrying the genotype or not. So we may conclude that the presence of -1082A allele and in particular of -1082A/-819T/-592A haplotype, associated with a low production of anti-inflammatory cytokine IL-10, may be considered as an additive and independent genetic risk factor for AD.

Genotype frequencies of the +874T-->A single nucleotide polymorphism in the first intron of the interferon-gamma gene in a sample of Sicilian patients affected by tuberculosis.

In the light of the key role played by interferon (IFN)-gamma in the control of tuberculosis, in the present paper we have evaluated the distribution of the functional +874T --> A IFN-gamma single nucleotide polymorphism (SNP) in Sicilian patients affected by tuberculosis. Our aim was to determine whether there is an association between the TT genotype, which has been suggested to be linked to an increased production of IFN-gamma, and resistance to chronic tuberculosis. DNA samples were obtained from 45 patients and 97 healthy controls. Polymorphism at +874 was identified using amplification refractory mutational system methodology. The +874T SNP was less frequent in patients than in controls (0.42 vs. 0.50) but the difference was not significant. The +874TT genotype, which has been suggested to be associated with high IFN-gamma production, was significantly decreased in the patients. Thus, resistance to chronic lung tuberculosis might be associated with a genetically determined high IFN-gamma production capacity. In conclusion, the present data add another piece of evidence to the complex puzzle of genetic and environmental factors involved in control of infectious diseases. Studies on cytokine gene polymorphisms may elucidate the complex network of trans-interactive genes influencing the type and strength of responses to environmental stressors and may help to identify the genetic factors that affect survival in humans.

Association between the MHC class I gene HFE polymorphisms and longevity: a study in Sicilian population.

Classes I and II human leukocyte antigens (HLA) genes encode highly polymorphic heterodimeric glycoproteins involved in the control of immune responses. The HLA class I gene HFE seemingly no longer participates in immunity because it has lost its ability to bind peptides and it has acquired the ability to form complex with the receptor for iron-binding transferrin by regulating iron uptake by intestinal cells. Thus, it indirectly regulates immune responses too, because iron availability plays a role in specific and non-specific immune responses. The distribution of HFE polymorphisms in Sicilian centenarians and nonagenarians was studied to evaluate if HFE alleles might be represented differently in people selected for longevity. DNA samples were obtained from 106 young controls (age range from 22 to 55 years; 40 men and 66 women) and 35 elderly subjects (age range from 91 to 105 years; seven men and 28 women). Samples were typed for C282Y, H63D and S65C alleles using polymerase chain reaction and sequence specific primers. Among the young individuals, none was heterozygous for the C282Y or for S65C mutation. Twenty-six were heterozygous for H63D mutation. Among the elderly subjects, 11 were heterozygous for the C282Y mutation or for H63D mutation. None was heterozygous for the S65C mutation. No compound heterozygous individuals (C282Y/H63D) were found. A highly significant difference was observed in frequencies of C282Y alleles between the young and the elderly subjects on the whole. By analysing polymorphisms according to gender, heterozygous subjects for C282Y were found both in old men and in old women, but by comparing the allele frequencies to those of young people significance was attained only in women. Concerning H63D polymorphisms, no significant differences were observed, between old and young people, both in men and in women. Possession of C282Y allele, known to be associated with an increase of iron uptake, significantly increases women possibility to reach longevity. Thus, present data adds another piece of evidence to the complex puzzle of genetic and environmental factors involved in control of lifespan expectancy in humans.

Gender-specific association between -1082 IL-10 promoter polymorphism and longevity.

Ageing is characterized by a pro-inflammatory status, which could contribute to the onset of major age-related diseases. Thus, genetic variations in pro- or anti-inflammatory cytokines might influence successful ageing and longevity. IL-10 is an appropriate candidate because it exerts powerful inhibitory effects on pro-inflammatory function. IL-10 production is controlled by several polymorphic elements in the 5' flanking region of IL-10 gene on 1q32 locus, involving alleles at two microsatellite regions and several polymorphisms in promoter region. We analysed in 190 Italian centenarians (>99 years old, 159 women and 31 men) and in 260 <60 years old control subjects (99 women and 161 men), matched for geographical distribution, genotype frequencies for -1082G-->A, -819C-->T and -592C-->A IL-10 proximal promoter gene biallelic polymorphisms by sequence specific probes. -1082G homozygous genotype was increased in centenarian men (P < 0.025) but not in centenarian women. No difference was found between centenarians and control subjects regarding the other two polymorphisms. The presence of -1082GG genotype, suggested to be associated with high IL-10 production, significantly increases the possibility to reach the extreme limit of human lifespan in men. Together with previous data on other polymorphic loci (Tyrosine Hydroxylase, mitochondrial DNA, IL-6, haemochromatosis, IFN-gamma), this finding points out that that gender is a major variable in the genetics of longevity, suggesting that men and women follow different strategies to reach longevity. Concerning the biological significance of this association, we have not searched for functional proves that IL-10 is involved. Thus, we should conclude that our data only suggest that a marker on 1q32 genomic region may be involved in successful ageing in man. However, recent data on IL-6 and IFN-gamma genes suggest that longevity is negatively associated with genotypes coding for a pro-inflammatory profile. Thus, it is intriguing that the possession of -1082G genotype, suggested to be associated with IL-10 high production, is significantly increased in centenarians.

A genetically determined high setting of TNF-alpha influences immunologic parameters of HLA-B8,DR3 positive subjects: implications for autoimmunity.

The 8.1 ancestral haplotype (AH) is a common Caucasoid haplotype carried by most people who type for HLA-B8,DR3. It seems unique in its association with a wide range of immunopathologic diseases. Healthy subjects bearing this haplotype demonstrate several alterations of immune response. This article will focus on the identification of the mechanism(s) of disease susceptibility of 8.1 AH. In 13 carriers of 8.1 AH, and 43 negative patients, enzyme immune assays serum levels of tumor necrosis factor (TNF)-alpha, soluble endothelial leukocyte adhesion molecule-1 (sELAM-1), cortisol, and interleukin(IL)-10 were determined. In addition, quantification of cytokine produced in vitro after mitogen stimulation was studied, and all subjects were genotyped for alleles at -592, -819, and -1082 nucleotides of IL-10 gene 5' flanking region, which is known to control IL-10 production. Results revealed that 8.1 AH is associated with a high in vivo and in vitro production of TNF-alpha, which in turn seems responsible for increased serum levels of sELAM-1, cortisol, and IL-10. On the contrary, in vitro production of IL-10 is not increased in these patients and there are no differences in allele promoter frequencies between the two groups that might explain the differences in IL-10 serum values. Thus, serum values seem to be the result of the effects of increased serum levels of TNF-alpha and cortisol. In conclusion, the increased spontaneous release of TNF-alpha, which modifies a certain number of immunologic parameters, may be the most characterizing feature of 8.1 AH. The consequent modification of the immunologic scenario might be involved in the predisposition to the impressive number of diseases and the changes in immune response observed in the patients studied.

HLA, aging, and longevity: a critical reappraisal.

Despite a large number of studies, available data do not allow at present to reach definitive and clear conclusions on role of HLA on longevity, owing to major methodological problems, such as serological and molecular typing of different loci, insufficient sample sizes, different inclusion criteria and age cut-off, inappropriate mixing of data referred to people from 58 to over 100 years of age, inappropriate control matching, and neglected consideration of sex-related effects and the different genetic make-up of studied populations. However, within this confused scenario, some data emerge. First, two studies that do not fit the biases above discussed show that some HLA alleles are associated with longevity. However, some of these alleles may confer an increased risk to undergo a variety of diseases. Second, longevity may be associated with an increased homozygosity at HLA loci. Third, an intriguing association between longevity and the 8.1 ancestral haplotype (AH), which has been proven to be associated with a variety of immune dysfunctions and autoimmune diseases, apparently emerges. This association appears to be a sex-specific (males) longevity contributor, and it is particularly interesting, taking into account that a type 2 (early infancy) --> type 1 (adulthood) --> type 2 (aging) shift of cytokine profile occurs lifelong, and that individuals bearing this haplotype show a type 2 immune responsiveness (note that type 1 cytokines mainly enhance cellular responses, whereas type 2 cytokines predominantly enhance humoral responses). On the whole, the (sex specific) association of longevity with alleles or haplotypes of several genes related to risk factors for a variety of diseases (cardiovascular diseases, cancer), including HLA alleles and haplotypes, is not unexpected on the basis of previous studies on the genetics of longevity in centenarians. This association can be interpreted under the perspective of a well known evolutionary theory of aging (antagonistic pleiotropy). This theory predicts that the same gene (or allele or haplotype) can have different roles (positive or negative) in different periods of the life span. Thus, the 8.1 AH should exert a positive effect during the infancy and aging but not in adulthood, when, indeed it is associated to susceptibility to a variety of diseases.

Glucose-induced loss of glycosyl-phosphatidylinositol-anchored membrane regulators of complement activation (CD59, CD55) by in vitro cultured human umbilical vein endothelial cells.

AIMS/HYPOTHESIS: This study examines whether increased glucose concentrations are responsible for a decreased expression of membrane regulators of complement activation molecules. The effect of high glucose in determining an increase in membrane attack complex deposition on endothelial cells was also investigated. METHODS: Endothelial cells were isolated from umbilical cord tissue, cultured in the presence of increased concentrations of glucose, and the expression of CD46, CD55, and CD59 was detected by ELISA (enzyme-linked immunosorbent assay) and by flow cytometry. Glucose-treated endothelial cells were also incubated with antiendothelial cell antibodies and fresh complement to assess the amount of membrane attack complex formation. RESULTS: High concentrations of glucose decreased the expression of CD59 and CD55 by endothelial cells in a time-dependent and glucose concentration-dependent manner without affecting CD46 expression. High concentrations of soluble CD59 were found in the supernatants of cells treated with high glucose. The decrease in CD59 expression induced by high glucose concentrations was reversed by coincubation of cells with a calcium channel blocking agent (Verapamil). All of these effects were not reproduced by osmotic control media. Cells treated with concentrations of high glucose were more susceptible to complement activation and membrane attack complex formation after exposure to antiendothelial cell antibodies. CONCLUSION/INTERPRETATION: We speculate that hyperglycaemia could directly contribute to a loss of CD59 and CD55 molecules through a calcium-dependent phosphoinositol-specific phospholipase C activation and subsequent regulation of cell wall expression of GPI-anchored proteins. This phenomenon could facilitate the activation of a complement pathway and could play a part in the aetiology of endothelial dysfunction in diabetes.