Browsing by Author "Vasconcelos, C."
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- Apoe isoforms in patients with psoriasisPublication . Ferreira, J.C.P.; Torres, T.; Carvalho, C.A.; Bettencourt, A.; Leal, B.; Vasconcelos, C.; Costa, P.P.; Selores, M.; Silva, B.M.Introduction: Psoriasis is a chronic inflammatory skin disease affecting 2–3% of the world population. Patients with psoriasis (Ps) have higher prevalence of lipid disorders when compared to unaffected individuals. These patients, especially those with severe and prolonged disease, have an increased morbidity and mortality from cardiovascular events. Apolipoprotein E (ApoE), a protein involved in lipid metabolism, cholesterol and phospholipid transport, has functionally relevant gene variants. It has been described that the e4 allele may increase the risk to develop atherosclerosis, and the e2 allele has been associated with hyperlipoproteinemia type III. An increased risk of psoriasis among persons with these two alleles has also been reported. Nevertheless, the role of ApoE in Psoriasis remains controversial. Objectives: The aim of this work was to investigate the relationship between APOE-e2/e3/e4 variants and psoriasis in a Portuguese population. Materials and Methods: A cohort of 178 unrelated (74 females, 104 males) severe psoriatic patients [according to the Psoriasis Area and Severity Index (PASI)] from Centro Hospitalar do Porto/Hospital de Santo Ant onio and 285 ethnically-matched healthy controls were studied. Genotyping of APOE was performed using a Polymerase chain reaction restriction fragment-length polymorphism (PCR-RFLP) assay. Results: The frequency of the e4 allele was significantly higher in patients than in controls [(11.5% vs. 7.6%), p = 0.044, OR=1.57 (1.01–2.45)]. Conclusion: The ApoE e4 isoform could be a risk factor for psoriatic disease in this population. Our result is in agreement with previous studies in a Spanish population that associated the e4 isoform with severe psoriasis. These results support the hypothesis that ApoE has a modulatory role in inflammatory conditions.
- Association between vitamin D receptor (VDR) gene polymorphisms and systemic lupus erythematosus in Portuguese patientsPublication . Carvalho, C.; Marinho, A.; Leal, B.; Bettencourt, A.; Boleixa, D.; Almeida, I.; Farinha, F.; Costa, P.P.; Vasconcelos, C.; Silva, B.M.Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin, in which both genetic and environmental factors are involved. One such environmental factor is vitamin D, a vital hormone that plays a specific function in the immune system homeostasis, acting through a nuclear receptor (VDR) expressed in all immune cells. Several polymorphisms of the gene that encodes this receptor have been described. Though inconsistently, these polymorphisms have been associated with clinical manifestations and SLE development.The aim of this study was to determine the possible association between VDR gene polymorphisms (BsmI, ApaI, TaqI e FokI) and SLE susceptibility and severity, in a cohort of lupus patients from the north of Portugal.A total of 170 patients (F = 155, M = 15; age = 45 ± 13.4 years) with SLE (diagnosed according the American College of Rheumatology criteria) with at least five years of disease evolution and followed in the Autoimmune Disease Clinical Immunology Unit of Centro Hospitalar do Porto were studied. Patients and 192 ethnicity-matched controls were genotyped for BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236) and FokI (rs2228570) polymorphisms by TaqMan allelic discrimination assay. Disease severity was assessed by SLICC damage score, number of affected organs, number of severe flares and pharmacological history.SLE patients with the CT genotype of FokI polymorphism have a higher SLICC value (p = 0.031). The same result was observed for the group of patients with the TT genotype of TaqI polymorphism (p = 0.046). No differences were observed in VDR genotype between patients and controls. Also, we observed that the other clinical features analysed were not influenced by VDR polymorphisms.Our study confirms a possible role of VDR gene polymorphisms in SLE. A positive association was found between VDR polymorphisms and SLE severity (chronic damage). The presence of CT genotype of FokI and TT genotype of TaqI seems to confer a worse prognosis and may constitute a risk factor for higher long-term cumulative damage in SLE patients.
- CCR5-Delta32: Implications in SLE developmentPublication . Carvalho, C.; Calvisi, S.L.; Leal, B.; Bettencourt, A.; Marinho, A.; Almeida, I.; Farinha, F.; Pinho-Costa, P.; Silva, B.M.; Vasconcelos, C.Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease with strong genetic and environmental components. Previous studies have shown increased levels of several chemokines in active SLE. C-C chemokine receptor type 5 (CCR5) is involved in the recruitment of inflammatory cells into tissues, and mechanisms modulating CCR5 expression and function may interfere in SLE development, influencing the clinical course of the disease. The aim of this study was to evaluate the possible association between the CCR5{increment}32 base-pair deletion polymorphism and SLE disease in a group of Portuguese patients. A total of 219 patients with SLE and 205 healthy individuals were studied. The frequency of CCR5[del]32 heterozygotes was lower in patients with SLE than in controls (8% vs. 15% OR = 0.5162; P = 0.0319), suggesting a protective association between CCR5[del]32 allele and SLE. These results highlight the protective role of Th1 cells that express CCR5 in SLE pathogenesis.
- Compensatory T-Cell Regulation in Unaffected Relatives of SLE Patients, and Opposite IL-2/CD25-Mediated Effects Suggested by Coreferentiality ModelingPublication . Fesel, C.; Barreto, M.; Ferreira, R.C.; Costa, N.; Venda, L.L.; Pereira, C.; Carvalho, C.; Morães-Fontes, M.F.; Ferreira, C.M.; Vasconcelos, C.; Viana, J.F.; Santos, E.; Martins, B.; Demengeot, J.; Vicente, A.M.In human systemic lupus erythematosus (SLE), diverse autoantibodies accumulate over years before disease manifestation. Unaffected relatives of SLE patients frequently share a sustained production of autoantibodies with indiscriminable specificity, usually without ever acquiring the disease. We studied relations of IgG autoantibody profiles and peripheral blood activated regulatory T-cells (aTregs), represented by CD4(+)CD25(bright) T-cells that were regularly 70-90% Foxp3(+). We found consistent positive correlations of broad-range as well as specific SLE-associated IgG with aTreg frequencies within unaffected relatives, but not patients or unrelated controls. Our interpretation: unaffected relatives with shared genetic factors compensated pathogenic effects by aTregs engaged in parallel with the individual autoantibody production. To study this further, we applied a novel analytic approach named coreferentiality that tests the indirect relatedness of parameters in respect to multivariate phenotype data. Results show that independently of their direct correlation, aTreg frequencies and specific SLE-associated IgG were likely functionally related in unaffected relatives: they significantly parallelled each other in their relations to broad-range immunoblot autoantibody profiles. In unaffected relatives, we also found coreferential effects of genetic variation in the loci encoding IL-2 and CD25. A model of CD25 functional genetic effects constructed by coreferentiality maximization suggests that IL-2-CD25 interaction, likely stimulating aTregs in unaffected relatives, had an opposed effect in SLE patients, presumably triggering primarily T-effector cells in this group. Coreferentiality modeling as we do it here could also be useful in other contexts, particularly to explore combined functional genetic effects.
- Hypercholesterolemia: A disease with expression from childhoodPublication . Espinheira, M.C.; Vasconcelos, C.; Medeiros, A.M.; Alves, A.C.; Bourbon, M.; Guerra, A.Hypercholesterolemia results from an alteration, genetic or acquired, in lipoprotein metabolism. Evidence that hypercholesterolemia is associated with the atherosclerotic process from childhood justifies the screening of high-risk children and initiation of therapy at preschool ages.
- IL-6 and TNF-alpha polymorphisms in portuguese psoriatic patientsPublication . Ferreira, J.P.; Torres, T.; Carvalho, C.; Bettencourt, A.; Leal, B.; Vasconcelos, C.; Costa, P.P.; Selores, M.; Silva, B.M.Introduction: Cytokines regulate the growth, function and differentiation of cells and help to steer immune response and inflammation. In this study we focused our attention in two proinflammatory cytokines: IL-6 and TNFa. It is known that their overexpression is responsible for initiation, maintenance and recurrence of skin lesions in psoriatic patients. Therefore, it is important to investigate genetic biomarkers with functional effects in the genes of those cytokines that could help to predict the severity of Psoriasis. Objectives: To investigate the hypothesis that allelic variants in IL-6 and TNF-a genes are a risk factor for the developing of severe Psoriasis. Materials and Methods: A cohort of 178 (74 females, 104 males) psoriatic patients with severe plaque type psoriasis [according to the Psoriasis Area and Severity Index (PASI)] and 206 healthy individuals were selected. Several polymorphisms in the IL-6 gene (rs1800795, rs1800796, rs2069827, rs2069840) and TNF-a (rs361525, rs1799964, rs1800629) promoter region were genotyped. SNP genotyping was performed using Mass Spectrometry (MassARRAY iPLEX–Sequenom). Results: We observed a lower frequency in the minor allele (C) of the TNFa rs1799964 SNP in psoriatic patients, compared with controls [(21.9% vs. 29.4%), p = 0.02, OR = 0.675 (0.49–0.94)]. The frequency of the CC genotype in patients was 3.93% while in the healthy control group it was 9.22% [(p = 0.04, OR = 0.403 (0.17–0.98)]. No statistical significant differences were found in the other polymorphisms. Conclusion: Our data suggest that the rs1799964 C allele could be a protective factor for developing severe psoriasis. These results were similar to the findings of Gallo et al (2012) in a Spanish population. The mechanism to explain this association remains elusive, given the lack of evidence of a functional association.
- Influence of interleukin-6 gene polymorphisms in epicardial adipose tissue and coronary artery calcification in patients with psoriasisPublication . Torres, T.; Bettencourt, N.; Ferreira, J.; Carvalho, C.; Mendonça, D.; Pinho-Costa, P.; Vasconcelos, C.; Selores, M.; Silva, B.Psoriasis is currently considered a systemic inflammatory disorder associated with several comorbidities and increased risk of cardiovascular disease (CVD)1 cytokines are overexpressed cutaneous and systemically and may be responsible for skin lesions but also for psoriasis-associated conditions surrounding the heart, is now regarded as an important factor in the pathogenesis of coronary atherosclerosis and CVD, through inflammatory burden proximal to the coronary arteries, and has been shown to be increased in psoriasis patients independently of abdominal visceral fat (AVF) and to be associated with sub-clinical atherosclerosis IL-6 has been implicated in the pathogenesis of psoriasis1 but also of abdominal obesity atherosclerosis and CVD4 30% of total circulating concentrations in healthy subjects thought to be influenced by polymorphisms in their gene loci, and this may contribute to the development of psoriasis, but also excess adiposity and psoriasis has been investigated that could predict which patients are at risk of developing psoriasis-linked cardiovascular comorbidities may permit an earlier management, with important clinical implications. This study aimed to evaluate the potential contribution of four IL-6 genetic variants (rs1800795[-174G>C], rs1800796[-572G>C], rs2069827[-1426G>T], rs2069840[-1753C>G]) in psoriasis susceptibility and its influence in EAT and coronary artery calcification (CAC) in severe psoriasis patients.
- Influence of TNF-α gene polymorphisms in coronary artery calcification in psoriasis patientsPublication . Torres, T.; Bettencourt, N.; Ferreira, J.; Carvalho, C.; Mendonca, D.; Pinho-Costa, P.; Vasconcelos, C.; Selores, M.; Silva, B.Psoriasis is a systemic inflammatory disorder associated with numerous medical comorbidities and increased risk of cardiovascular disease (CVD. Psoriasis’ systemic inflammation may play an important role in the accelerated atherosclerosis observed in these patients2 as inflammatory processes play a key role in atherogenesis. Psoriasis and atherosclerosis share some pathological features including endothelial dysfunction, alteration in angiogenesis and some inflammatory pathways. TNF-a is a potent pro-inflammatory cytokine that has been implicated in psoriasis and atherosclerosis pathogenesis and its synthesis is tightly regulated at gene transcription level. TNF-a gene promoter region contains several single-nucleotide polymorphisms (SNP) that influence TNF-a production. Several TNF-a gene polymorphisms have been associated with psoriasis and CVD. A recent meta-analysis suggested that TNF-a rs1800629(308G/A) polymorphism was associated with decreased risk of psoriasis, whereas TNF-a rs361525(238G/A) was associated with increased risk. Regarding TNF-a rs1799964 (1031T/C) polymorphism, existing data are limited and contradictory.8 Since psoriasis morbidity and mortality are strongly linked to accelerated atherosclerosis, determining the genetic contribution for cardiovascular morbidity in psoriasis patients becomes an issue of major importance. The aim of this study was to evaluate the contribution of TNF-a rs361525(238G/A), TNF-a rs1800629(308G/A) and TNFa rs1799964(1031T/C) gene polymorphisms to coronary artery calcification (CAC) in severe psoriasis patients.
- Low frequency of CD4+CD25+ Treg in SLE patients: a heritable trait associated with CTLA4 and TGFbeta gene variantsPublication . Barreto, M.; Ferreira, R.C.; Lourenço, L.; Moraes-Fontes, M.F.; Santos, E.; Alves, M.; Carvalho, C.; Martins, B.; Andreia, R.; Viana, J.F.; Vasconcelos, C.; Mota-Vieira, L.; Ferreira, C.; Demengeot, J.; Vicente, A.M.CD4+CD25+ regulatory T cells play an essential role in maintaining immune homeostasis and preventing autoimmunity. Therefore, defects in Treg development, maintenance or function have been associated with several human autoimmune diseases including Systemic Lupus Erythematosus (SLE), a systemic autoimmune disease characterized by loss of tolerance to nuclear components and significantly more frequent in females. RESULTS: To investigate the involvement of Treg in SLE pathogenesis, we determined the frequency of CD4+CD25+CD45RO+ T cells, which encompass the majority of Treg activity, in the PBMC of 148 SLE patients (76 patients were part of 54 families), 166 relatives and 117 controls. SLE patients and their relatives were recruited in several Portuguese hospitals and through the Portuguese Lupus Association. Control individuals were blood donors recruited from several regional blood donor centers. Treg frequency was significantly lower in SLE patients than healthy controls (z = -6.161, P < 0.00001) and intermediate in the relatives' group. Remarkably, this T cell subset was also lower in females, most strikingly in the control population (z = 4.121, P < 0.001). We further ascertained that the decreased frequency of Treg in SLE patients resulted from the specific reduction of bona fide FOXP3+CD4+CD25+ Treg. Treg frequency was negatively correlated with SLE activity index (SLEDAI) and titers of serum anti-dsDNA antibodies. Both Treg frequency and disease activity were modulated by IVIg treatment in a documented SLE case. The segregation of Treg frequency within the SLE families was indicative of a genetic trait. Candidate gene analysis revealed that specific variants of CTLA4 and TGFbeta were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency. CONCLUSION: SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells. Treg frequency is highly heritable within SLE families, with specific variants of the CTLA4 and TGFbeta genes contributing to this trait, while FOXP3 contributes to SLE through mechanisms not involving a modulation of Treg frequency. These findings establish that the genetic components in SLE pathogenesis include genes related to Treg generation or maintenance.