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Giuseppina Candore

Publications and source records attributed to Giuseppina Candore.

47 records · Page 3Linked to original sources

Association between the HLA-DR alleles and longevity: a study in Sardinian population.

Human longevity may be correlated with optimal functioning of the immune system, suggesting that genetic determinants of longevity also resides in those polymorphisms for the immune system genes that regulate immune responses as histocompatibility (HLA) antigens. However, conflicting results have been obtained. Some well planned and designed association studies performed in Caucasians suggest that longevity is associated with positive selection of alleles (i.e. HLA-DR11) or haplotypes (i.e. HLA-B8,DR3) that confer resistance to infectious diseases, respectively, via peptide presentation or via antigen non-specific control of immune response. Association studies are subjected to a number of possible confounding factors, the homogeneity of the population in term of geographical origin among others. Because of the lack of large-scale heterogeneity, the Sardinians represent a suitable population for association studies addressed to dissect the complex traits as longevity. Thus, we have evaluated, by the amplification refractory mutation system/polymerase chain reaction, HLA-DR frequencies in 120 centenarians (79 women and 41 men) and 86 controls (53 women and 33 men) from Sardinia, to validate, in this very homogeneous population, the associations between HLA alleles or haplotypes and longevity observed in other Caucasoid populations. No significant differences were obtained by analysing the differences between Centenarians and controls except for HLA-DRB1*15 that was increased in centenarians. However, the significance was not maintained by multiplying P values for the number of alleles under study. Thus, in Sardinian centenarians, we were not able to confirm the findings observed in the well planned and designed studies performed in other Caucasoid populations. Besides, HLA HFE gene polymorphisms have been recently demonstrated to be associated with longevity in the Sicilian population but not in Danish one. On the whole these findings clearly show that HLA/longevity associations are population-specific, being heavily affected by the population-specific genetic and environmental history. So, in our opinion, HLA genes might be considered survival genes not longevity genes.

Aged↗

Pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype: a genetically determined defect of C4 influences immunological parameters of healthy carriers of the haplotype.

Subjects with certain HLA alleles have a higher risk of specific autoimmune diseases than those without these alleles. The 8.1 ancestral haplotype (AH) is a common Caucasoid haplotype carried by most people who type for HLA-B8,DR3. It is unique in its association with a wide range of immunopathological diseases. To gain insight into the identification of the mechanism(s) of disease susceptibility of 8.1 AH carriers, we have investigated the prevalence of circulating immune complexes and non-organ-specific autoantibodies in healthy carriers of the haplotype. The results show that carriers of 8.1 AH display both a significant increased prevalence of immune complexes and higher titers of anti-nuclear autoantibodies. This AH carries a single segment characterized by no C4A gene. This null allele does not code for a functional C4A protein that likely plays an anti-inflammatory role being specialized in the opsonization and immunoclearance processes. So, this genetic defect has been claimed to allow that an increased production of autoantibodies directed vs. cells that have undergone apoptosis and are not efficiently disposed because a reduced antigenic clearance. The results obtained in the present study fit very well with this hypothesis. In the AH carriers the simultaneous high setting of tumor necrosis factor (TNF)-alpha may supply the autoantigens (providing an excess of apoptotic cells) that drive the autoimmune response. In conclusion, the C4 defect associated to the increased spontaneous release of TNF-alpha, modifying a certain number of immunological parameter may be the most characterizing feature of the 8.1 AH. In the majority of individuals, an autoimmune response clinically relevant will develop only in the presence of other immunological abnormalities.

Adult↗

Pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype: effect of multiple gene interactions.

Genetic studies have shown that individuals with certain HLA alleles have a higher risk of specific autoimmune disease than those without these alleles. Particularly, the association in all Caucasian populations of an impressive number of autoimmune diseases with genes from the HLA-B8,DR3 haplotype that is part of the ancestral haplotype (AH) 8.1 HLA-A1, Cw7, B8, TNFAB*a2b3, TNFN*S, C2*C, Bf*s, C4A*Q0, C4B*1, DRB1*0301, DRB3*0101, DQA1*0501, DQB1*0201 has been reported by different research groups. This haplotype, the more common one in northern Europe, is also associated in healthy subjects with a number of immune system dysfunctions. It has been proposed that a small number of genes within the 8.1 AH modify immune responsiveness and hence affect multiple immunopathological diseases. In this paper, the characteristic features of this haplotype that might give rise to these diverse conditions are reviewed, focusing on the role of multiple gene interactions in disease susceptibility of 8.1 AH.

Alleles↗

In vitro effects of fluticasone propionate on IL-13 production by mitogen-stimulated lymphocytes.

BACKGROUND: Corticosteroid administration produces multiple immunomodulatory effects, including down-regulation of cytokine production by CD4 T lymphocytes. Fluticasone propionate (FP) (Glaxo Smith&Kline, Greenford, UK), a highly lipophilic topical corticosteroid, has been shown to be safe and effective in the treatment of asthma and of both seasonal and perennial rhinitis. AIMS: To gain insight into the mechanisms of FP therapeutic effects, we evaluated interleukin (IL)-13 (a type 2 cytokine that seemingly plays a pivotal role in allergic mechanisms) production by mitogen-stimulated peripheral blood mononuclear cells (MNC) in vitro, treated or not with FP. METHODS: MNC from 10 healthy subjects and 10 asthmatic atopic patients with Parietaria allergy were stimulated v/v with phytohaemagglutinin (PHA) (50 gamma/ml) or with complete medium alone as a control. Culture supernatants, in vitro treated or not with 10(-7) or 10(-8) M FP, were collected after 48 or 72 h incubation. IL-13 production was assessed by enzyme-linked immunosorbent assay. In random selected samples, after 4 or 24 h of cell cultures, RNA was extracted and IL-4 and IL-5 reverse transcriptase-polymerase chain reaction (RT-PCR) products analyzed. RESULTS: At 48 h, there were no differences in IL-13 concentration in PHA-stimulated cultures between healthy subjects and asthmatic patients (93.6 +/- 18.9 versus 111.0 +/- 25.1 pg/ml). At 72 h, similar results were obtained (63.9 +/- 3.0 versus 73.3 +/- 2.5 pg/ml, respectively). At this time, however, IL-13 concentrations were significantly decreased versus 48 h both in asthmatics (p < 0.001) and in controls (p < 0.001). Treatment with 10(-7) M FP significantly reduced IL-13 production in healthy subjects and asthmatic patients both at 48 h (93.6 +/- 18.9 versus 50.50 +/- 10.6 pg/ml, p < 0.001, and 111.0 +/- 25.1 versus 59.3 +/- 13.6 pg/ml, p < 0.001, respectively) and at 72 h (63.9 +/- 9.6 versus 35.5 +/- 4.4 pg/ml, p < 0.001, and 73.3 +/- 8.0 versus 40.7 +/- 4.5 pg/ml, p < 0.001, respectively). Similar results were obtained with 10(-8) M FP at 48 and 72 h. Accordingly, evaluation of RT-PCR products from selected cell samples showed a FP dosage-dependent inhibition of IL-4 and IL-5 mRNA production both for healthy subjects and asthmatic patients. CONCLUSIONS: FP in vitro impairs IL-13 production by PHA-stimulated MNC from asthmatic and control subjects. This strengthens previous suggestions that IL-13 inhibition by steroids may, at least in part, account for their therapeutic effects.

Administration, Topical↗

Measurement of inflammatory mediators of eosinophils and lymphocytes in blood in acute asthma: serum levels of ECP influence the bronchodilator response.

The aim of this study was to assess the relevance of immunoinflammatory markers on the response to short acting beta(2)-agonist in acute asthma exacerbation. Thus, we measured serum eosinophil cationic protein (ECP) levels and sIL-2R at acute exacerbation in 52 adult patients with atopic asthma, and assessed forced expiratory volume in 1 s (FEV(1)) before and after the administration of aerosolized salbutamol. After a cumulative dose of salbutamol causing a 10% improvement in FEV(1) from baseline [CD10, i.e. cumulative doses of salbutamol (800 microg) causing an improvement in FEV(1) from baseline to 10%] the patients were divided into two groups: group A with CD <10 and group B with CD >10. The bronchodilator response, as defined by a DeltaFEV(1) (percentage of predictive value of FEV(1)) of > or =10 predictive value, was shown by 40% of the patients. After 200, 400 and 800 microg of salbutamol, significant differences of FEV(1) with respect to baseline values were, respectively, p = 0.049, 0.0039 and 0.0014. In contrast, no significant difference of the means of FEV(1) between the doses of salbutamol was observed. Significant differences of DeltaFEV(1) between 200 and 400 microg (p = 0.0002) and between 200 and 800 microg (p < 0.0001) were observed, but not between 400 and 800 microg of salbutamol. There were significant correlations between baseline values of predictive FEV(1) and serum ECP levels (rho = -0.60, p < 0.0001) and sIL-2R levels (rho = -0.35, p = 0.01) respectively. Besides, a correlation between DeltaFEV(1) and serum ECP levels (rho = -0.53, p < 0.0001) was observed, whereas no correlation was found between DeltaFEV(1) and sIL-2R. By analyzing differences between the two groups (A and B) for serum ECP levels, sIL-2R and blood eosinophil count, a significant difference was found for serum ECP levels. We conclude that subjects with acute exacerbation of asthma show high serum levels of ECP and sIL-2R and, more interestingly, that the response to brochodilator was higher in patients with lower serum ECP levels.

Adolescent↗

Frequency of the HFE gene mutations in five Italian populations.

Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region. The single point mutation 845A, changing cysteine at position 282 to tyrosine (C282Y), in this gene has been identified as the main genetic basis of hereditary hemochromatosis. Two other mutations, 187G, a histidine to aspartate at amino acid 63 (H63D), and 193T, a serine to cysteine at amino acid 65 (S65C), appear to be associated with milder forms of hereditary hemochromatosis. There is a high prevalence of the C282Y mutation in northern European populations, whereas in those of the Mediterranean basin the prevalence seems low and almost absent in Far East countries. This mutation seems usually to occur on the ancestral haplotype 7.1. Accordingly, a Celtic origin of this mutation has been suggested. The aim of this study was to determine the frequency of HFE gene mutations in five geographic regions in Italy. Samples were tested for C282Y, H63D, and S65C mutations of the HFE gene according to methods of each laboratory and the results were standardized with the exchange of typed samples between the different laboratories. In addition, C282Y-positive DNA samples were typed for D6S105 allele 8 and HLA-A3 by ARMS-PCR. We have found that the allele frequency of the C282Y mutation decreases from northeast Italy (Friuli, 6%) to northwest Italy (Piedmont, 4.8%) and to central Italy (Emilia-Romagna, 1.7%). However, this mutation is lacking in the two regions of the Mediterranean basin's center (Sicily and Sardinia). Accordingly, a significant difference in the frequency of the mutation was observed between these Italian regions (P = 0.07 x 10(-3)). In contrast, no difference was observed in allele frequency of H63D in the five Italian regions. Finally, as regards the S65C mutation a very low frequency was observed in Friuli, Emilia-Romagna, and Sardinia, whereas in Sicily and Piedmont we have not found this mutation. In conclusion, these data are consistent with the hypothesis that the C282Y mutation occurred in Caucasian populations of Celtic origin, whereas the H63D mutation is more ancient as demonstrated by the ubiquitous distribution.

Amino Acid Substitution↗

Inflammation, genes and zinc in ageing and age-related diseases.

Lifelong antigenic burden determines a condition of chronic inflammation, with increased lymphocyte activation and pro-inflammatory cytokine production. A large number of studies have documented changes in Zn metabolism in experimental animal models of acute and chronic inflammation and in human chronic inflammatory diseases. In particular, modification of zinc plasma concentration as well as intracellular disturbance of antioxidant intracellular pathways have been found associated to age-related inflammatory diseases, like atherosclerosis. Zinc deficiency is extremely diffused in aged people that are educated to avoid meat and other high Zn-content foods due to fear of cholesterol. Rather, they increase consumption of refined wheat products that lack of Zn, magnesium and other critical nutrients in consequence of refining process. On the other hand, plasma concentration of metallic ions like Zn is influenced by pro-inflammatory cytokines production. A major target of Zn may be NF-kB, a transcription factor critical for the expression of many pro-inflammatory cytokines whose production is finely regulated by extra- and intracellular activating and inhibiting factors interacting with regulatory elements on cytokine genes. Moreover, this factor is regulated by the expression of specific cellular genes involved in inflammation. So it is not surprising that Zn deficiency is constantly observed in aged patients affected by infectious diseases. On the other hand, cytokine genes are highly polymorphic and some of these polymorphisms have been found associated to age-related diseases as atherosclerosis. Therefore, Zn deficiency in individuals genetically predisposed to a dis-regulation of inflammation response, may play a crucial role, in causing adverse events and in reducing the probability of a successful aging.

Aging↗

Gamma/delta T lymphocytes are affected in the elderly.

gammadelta T lymphocytes are considered to represent a link between the inflammatory response and adaptive immunity. In the present paper we investigated whether these cells play any role in the remodeling of the immune system described in the elderly. We show that the absolute number of gammadelta T cells in peripheral blood of old and very old subjects is reduced. Moreover, gammadelta T cells from old people and centenarians show enhanced levels of the early activation marker CD69 both after culture in medium alone and in LPS-stimulated cells. Furthermore, they show a basal increased production of tumor necrosis factor (TNF)-alpha as evaluated at the single cell level. Additionally, the response of these cells to IPP in "in vitro" cultures is in part impaired. These results suggest that the high level of basal activation of gammadelta T cells is due to the "inflamed" environment. However, the changes in number and function of gammadelta T lymphocytes might influence the resolution of inflammatory immune responses in the elderly.

Adult↗

Allele frequencies of +874T-->A single nucleotide polymorphism at the first intron of interferon-gamma gene in a group of Italian centenarians.

Ageing is characterized by a pro-inflammatory status which could contribute to the onset of major age-related diseases such as cardiovascular diseases, neurodegeneration, osteoarthritis and osteoporosis, and diabetes. Thus, it can be hypothesized that genetic variations in pro- or anti-inflammatory cytokines might influence successful ageing and longevity. We have studied the distribution of +874T-->A interferon-gamma (IFN-gamma) polymorphisms in a large number of Italian centenarians to evaluate if the two alleles might be differently represented in people selected for longevity. DNA samples were obtained from 174 Italian centenarians (>99 years old, 142 women and 32 men) and from 248 <60-year-old control subjects (90 women and 158 men) matched for geographical distribution. Polymorphisms at +874 were identified by using amplification refractory mutational system methodology. The +874T allele was found less frequently in centenarian women than in centenarian men or in control women whereas no significant differences were observed in the distribution of the two alleles between male or female controls. Allele frequencies in centenarian men were not found significantly different from male controls. Possession of the +874A allele, known to be associated with low IFN-gamma production, significantly increases the possibility to achieve extended longevity, suggesting that the pro-inflammatory status characteristic of ageing may be detrimental for successful ageing. The datum that the allele was significantly increased in female but not male centenarians seems to strengthen the idea that gender may be a major variable in the biology of the ageing process. However, the present data add another piece of evidence to the complex puzzle of genetic and environmental factors involved in controlling life span expectancy in humans. Thus, studies on cytokine gene polymorphisms may promise to individuate a complex network of trans-interactive genes able to influence the type and strength of responses to environmental stressors and as a final result, thereby conditioning individual life expectancy.

Adult↗

Association between HFE mutations and acute myocardial infarction: a study in patients from Northern and Southern Italy.

There is interest in the role of iron in age-related diseases such as atherosclerosis. Tissue iron deposition could be harmful, because Fe(2+) can react with H(2)O(2) to form OH(-) radicals and Fe(2+) can react with O(2) to form reactive oxygen species. Free radicals react with cell membranes and cell organelles and could lead to the development of atherosclerosis by initiating lipid peroxidation. Hereditary hemochromatosis provides an opportunity for studying the effects of iron on cardiovascular disease. Some studies have shown that individuals who carried HFE mutations may be at greater risk of developing coronary heart disease than those without the mutations. In contrast, a large number of studies have reported no association between HFE mutations and coronary heart disease. These studies have possible confounding factors, such as the homogeneity of the population in term of geographical origin among others. We studied the relation between HFE mutations and acute myocardial infarction in two case-control studies involving two sets of subjects representing different age groups from different geographic regions in Italy. The first one was composed of 172 older patients (139 males and 33 females; mean age 67) and 207 healthy controls (91 males and 116 females; mean age 46) from Emilia-Romagna. The second one was composed of younger 77 patients (75 males and 2 females; mean age 41) and 172 healthy controls (75 males and 97 females, mean age: 38) from Sicily. All patients were genotyped for ApoE alleles, since the ApoE- epsilon 4 allele is considered a risk factor for cardiovascular diseases and can interfere with other genetic and environmental factors by modifying susceptibility to this disease. DNA typing for C282Y and H63D HFE alleles was performed also. There were no significant differences in frequencies of the different HFE alleles between acute myocardial infarction patients and controls in cohorts of both old and young patients. Also taking into account the presence or absence of the ApoE- epsilon 4 allele, no significant differences in H63D allele frequencies were observed. Thus, our study, performed in two samples of genetically homogeneous patients and controls, does not support the suggestion that HFE mutations may be associated with acute myocardial infarction in susceptible individuals.

Adult↗