Alessandra Meloni

@article{incani_-defensin_2017,

title = {β-defensin CNV is not associated with susceptibility to Candida albicans infections in Sardinian APS I patients.},

author = {Federica Incani and Carla Cossu and Alessandra Meloni and Valeria Faa and Maria Luisa Serra and Federico Dettori and Antonella Meloni and Maria Cristina Rosatelli},

url = {http://www.ncbi.nlm.nih.gov/pubmed/27682444},

doi = {10.1111/jop.12506},

issn = {1600-0714},

year  = {2017},

date = {2017-05-01},

journal = {Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology},

volume = {46},

number = {5},

pages = {393--397},

abstract = {OBJECTIVE The aim of this study was to investigate whether a variation in the genomic copy number (CNV) of the β-defensin cluster could be associated with the pre-disposition to chronic mucocutaneous candidiasis (CMC) in Sardinian APECED patients. SUBJECTS AND METHODS The β-defensin copy number variation was determined by MLPA analysis in 18 Sardinian APECED patients with CMC and in 21 Sardinian controls. Statistical analyses were performed with one-way ANOVA test. RESULTS No statistically significant results were observed between the patients and controls groups. CONCLUSIONS According to the results we have obtained, it appears that either β-defensin genomic CNV is not a modifier locus for CMC susceptibility in APECED patients, or any effect is too small for it to be detected using such sample size. An extensive study on APECED patients from different geographical areas might reveal the real implication of the β-defensin CNV in the susceptibility to Candida albicans infections.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{steri_overexpression_2017,

title = {Overexpression of the Cytokine BAFF and Autoimmunity Risk},

author = {Maristella Steri and Valeria Orrù and Laura M Idda and Maristella Pitzalis and Mauro Pala and Ilenia Zara and Carlo Sidore and Valeria Faà and Matteo Floris and Manila Deiana and Isadora Asunis and Eleonora Porcu and Antonella Mulas and Maria G Piras and Monia Lobina and Sandra Lai and Mara Marongiu and Valentina Serra and Michele Marongiu and Gabriella Sole and Fabio Busonero and Andrea Maschio and Roberto Cusano and Gianmauro Cuccuru and Francesca Deidda and Fausto Poddie and Gabriele Farina and Mariano Dei and Francesca Virdis and Stefania Olla and Maria A Satta and Mario Pani and Alessandro Delitala and Eleonora Cocco and Jessica Frau and Giancarlo Coghe and Lorena Lorefice and Giuseppe Fenu and Paola Ferrigno and Maria Ban and Nadia Barizzone and Maurizio Leone and Franca R Guerini and Matteo Piga and Davide Firinu and Ingrid Kockum and Izaura {Lima Bomfim} and Tomas Olsson and Lars Alfredsson and Ana Suarez and Patricia E Carreira and Maria J Castillo-Palma and Joseph H Marcus and Mauro Congia and Andrea Angius and Maurizio Melis and Antonio Gonzalez and Marta E {Alarc{ó}n Riquelme} and Berta M da Silva and Maurizio Marchini and Maria G Danieli and Stefano {Del Giacco} and Alessandro Mathieu and Antonello Pani and Stephen B Montgomery and Giulio Rosati and Jan Hillert and Stephen Sawcer and Sandra D'Alfonso and John A Todd and John Novembre and Gon{ç}alo R Abecasis and Michael B Whalen and Maria G Marrosu and Alessandra Meloni and Serena Sanna and Myriam Gorospe and David Schlessinger and Edoardo Fiorillo and Magdalena Zoledziewska and Francesco Cucca},

doi = {10.1056/NEJMoa1610528},

issn = {1533-4406},

year  = {2017},

date = {2017-01-01},

journal = {The New England Journal of Medicine},

volume = {376},

number = {17},

pages = {1615--1626},

abstract = {BACKGROUND: Genomewide association studies of autoimmune diseases have mapped hundreds of susceptibility regions in the genome. However, only for a few association signals has the causal gene been identified, and for even fewer have the causal variant and underlying mechanism been defined. Coincident associations of DNA variants affecting both the risk of autoimmune disease and quantitative immune variables provide an informative route to explore disease mechanisms and drug-targetable pathways. 

METHODS: Using case-control samples from Sardinia, Italy, we performed a genomewide association study in multiple sclerosis followed by TNFSF13B locus-specific association testing in systemic lupus erythematosus (SLE). Extensive phenotyping of quantitative immune variables, sequence-based fine mapping, cross-population and cross-phenotype analyses, and gene-expression studies were used to identify the causal variant and elucidate its mechanism of action. Signatures of positive selection were also investigated. 

RESULTS: A variant in TNFSF13B, encoding the cytokine and drug target B-cell activating factor (BAFF), was associated with multiple sclerosis as well as SLE. The disease-risk allele was also associated with up-regulated humoral immunity through increased levels of soluble BAFF, B lymphocytes, and immunoglobulins. The causal variant was identified: an insertion-deletion variant, GCTGT→A (in which A is the risk allele), yielded a shorter transcript that escaped microRNA inhibition and increased production of soluble BAFF, which in turn up-regulated humoral immunity. Population genetic signatures indicated that this autoimmunity variant has been evolutionarily advantageous, most likely by augmenting resistance to malaria. 

CONCLUSIONS: A TNFSF13B variant was associated with multiple sclerosis and SLE, and its effects were clarified at the population, cellular, and molecular levels. (Funded by the Italian Foundation for Multiple Sclerosis and others.).},

note = {See Editorials, Korn T, Oukka M. A BAFFling Association between Malaria Resistance and the Risk of Multiple Sclerosis. N Engl J Med. 2017 Apr 27;376(17):1680-1681. doi: 10.1056/NEJMe1700720.; Stohl W., Systemic lupus erythematosus: BAFF emerges from the genetic shadows. Nat Rev Rheumatol. 2017 Jun 15. doi: 10.1038/nrrheum.2017.99; Comabella M. Neuroimmunology: B cells and variant BAFF in autoimmune disease. Nat Rev Neurol. 2017 Jun 16. doi: 10.1038/nrneurol.2017.87.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{incani_aire_2014,

title = {AIRE acetylation and deacetylation: effect on protein stability and transactivation activity},

author = {Federica Incani and Maria Serra and Alessandra Meloni and Carla Cossu and Luisella Saba and Tiziana Cabras and Irene Messana and Maria C Rosatelli},

doi = {10.1186/s12929-014-0085-z},

issn = {1423-0127},

year  = {2014},

date = {2014-08-01},

journal = {Journal of Biomedical Science},

volume = {21},

pages = {85},

abstract = {BACKGROUND: The AIRE protein plays a remarkable role as a regulator of central tolerance by controlling the promiscuous expression of tissue-specific antigens in thymic medullary epithelial cells. Defects in AIRE gene cause the autoimmune polyendocrinopathy- candidiasis-ectodermal dystrophy, a rare disease frequent in Iranian Jews, Finns, and Sardinian population. 

RESULTS: In this study, we have precisely mapped, by mass spectrometry experiments, the sites of protein acetylation and, by mutagenesis assays, we have described a set of acetylated lysines as being crucial in influencing the subcellular localization of AIRE. Furthermore, we have also determined that the de-acetyltransferase enzymes HDAC1-2 are involved in the lysine de-acetylation of AIRE. 

CONCLUSIONS: On the basis of our results and those reported in literature, we propose a model in which lysines acetylation increases the stability of AIRE in the nucleus. In addition, we observed that the interaction of AIRE with deacetylases complexes inhibits its transcriptional activity and is probably responsible for the instability of AIRE, which becomes more susceptible to degradation in the proteasome.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{cocco_vitamin_2012,

title = {Vitamin Đ responsive elements within the HLA-DRB1 promoter region in Sardinian multiple sclerosis associated alleles},

author = {Eleonora Cocco and Alessandra Meloni and Maria Rita Murru and Daniela Corongiu and Stefania Tranquilli and Elisabetta Fadda and Raffaele Murru and Lucia Schirru and Maria Antonietta Secci and Gianna Costa and Isadora Asunis and Stefania Cuccu and Giuseppe Fenu and Lorena Lorefice and Nicola Carboni and Gioia Mura and Maria Cristina Rosatelli and Maria Giovanna Marrosu},

doi = {10.1371/journal.pone.0041678},

issn = {1932-6203},

year  = {2012},

date = {2012-01-01},

journal = {PloS One},

volume = {7},

number = {7},

pages = {e41678},

abstract = {Vitamin D response elements (VDREs) have been found in the promoter region of the MS-associated allele HLA-DRB1*15:01, suggesting that with low vitamin D availability VDREs are incapable of inducing *15:01 expression allowing in early life autoreactive T-cells to escape central thymic deletion. The Italian island of Sardinia exhibits a very high frequency of MS and high solar radiation exposure. We test the contribution of VDREs analysing the promoter region of the MS-associated DRB1 *04:05, *03:01, *13:01 and *15:01 and non-MS-associated *16:01, *01, *11, *07:01 alleles in a cohort of Sardinians (44 MS patients and 112 healthy subjects). Sequencing of the DRB1 promoter region revealed a homozygous canonical VDRE in all *15:01, *16:01, *11 and in 45/73 *03:01 and in heterozygous state in 28/73 *03:01 and all *01 alleles. A new mutated homozygous VDRE was found in all *13:03, *04:05 and *07:01 alleles. Functionality of mutated and canonical VDREs was assessed for its potential to modulate levels of DRB1 gene expression using an in vitro transactivation assay after stimulation with active vitamin D metabolite. Vitamin D failed to increase promoter activity of the *04:05 and *03:01 alleles carrying the new mutated VDRE, while the *16:01 and *03:01 alleles carrying the canonical VDRE sequence showed significantly increased transcriptional activity. The ability of VDR to bind the mutant VDRE in the DRB1 promoter was evaluated by EMSA. Efficient binding of VDR to the VDRE sequence found in the *16:01 and in the *15:01 allele reduced electrophoretic mobility when either an anti-VDR or an anti-RXR monoclonal antibody was added. Conversely, the Sardinian mutated VDRE sample showed very low affinity for the RXR/VDR heterodimer. These data seem to exclude a role of VDREs in the promoter region of the DRB1 gene in susceptibility to MS carried by DRB1* alleles in Sardinian patients.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{meloni_daxx_2010,

title = {DAXX is a new AIRE-interacting protein},

author = {Alessandra Meloni and Edoardo Fiorillo and Denise Corda and Federica Incani and Maria Luisa Serra and Antonella Contini and Antonio Cao and Maria Cristina Rosatelli},

doi = {10.1074/jbc.M109.037747},

issn = {1083-351X},

year  = {2010},

date = {2010-04-01},

journal = {The Journal of Biological Chemistry},

volume = {285},

number = {17},

pages = {13012--13021},

abstract = {The AIRE protein plays a remarkable role as a regulator of central tolerance by controlling the promiscuous expression of tissue-specific antigens in thymic medullary epithelial cells. Defects in the AIRE gene cause the autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, a rare disease frequent in Iranian Jews, Finns, and Sardinian population. To this day, the precise function of the AIRE protein in regulating transcription and its interacting proteins has yet to be entirely clarified. The knowledge of novel AIRE interactors and their precise role will improve our knowledge of its biological activity and address some of the foremost autoimmunity-related questions. In this study, we have used a yeast two-hybrid system to identify AIRE-interacting proteins. This approach led us to the discovery of a new AIRE-interacting protein called DAXX. The protein is known to be a multifunctional adaptor with functions both in apoptosis and in transcription regulation pathways. The interaction between AIRE and DAXX has been validated by in vivo coimmunoprecipitation analysis and colocalization study in mammalian cells. The interaction has been further confirmed by showing in transactivation assays that DAXX exerts a strong repressive role on the transcriptional activity of AIRE.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}