Maria Laura Idda

@article{pmid33123155,

title = {Evolutionarily Selected Overexpression of the Cytokine BAFF Enhances Mucosal Immune Response Against P. falciparum},

author = { V. Lodde and M. Floris and I. Beerman and R. Munk and R. Guha and M. Steri and V. Orrù and K. Abdelmohsen and P. D. Crompton and M. Gorospe and M. L. Idda and F. Cucca},

year  = {2020},

date = {2020-01-01},

journal = {Front Immunol},

volume = {11},

pages = {575103},

abstract = {We have previously shown that a variant of the TNFSF13B gene that we called BAFF-var increases the production of the cytokine BAFF, upregulating humoral immunity and increasing the risk for certain autoimmune diseases. In addition, genetic population signatures revealed that BAFF-var was evolutionarily advantageous, most likely by increasing resistance to malaria infection, which is a prime candidate for selective pressure. To evaluate whether the increased soluble BAFF (sBAFF) production confers protection, we experimentally assessed the role of BAFF-var in response to malaria antigens. Lysates of erythrocytes infected with Plasmodium falciparum (iRBCs) or left uninfected (uRBCs, control) were used to treat peripheral blood mononuclear cells (PBMCs) with distinct BAFF genotypes. The PBMCs purified from BAFF-var donors and treated with iRBCs showed different levels of specific cells, immunoglobulins, and cytokines as compared with BAFF-WT. In particular, a relevant differential effect on mucosal immunity B subpopulations have been observed. These findings point to specific immune cells and molecules through which the evolutionary selected BAFF-var may have improved fitness during P. falciparum infection.},

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pubstate = {published},

tppubtype = {article}

}

@article{pmid30784348,

title = {NF90 regulation of immune factor expression in response to malaria antigens},

author = { M. L. Idda and V. Lodde and G. Galleri and J. L. Martindale and R. Munk and K. Abdelmohsen and F. Cucca and M. Gorospe},

year  = {2019},

date = {2019-01-01},

journal = {Cell Cycle},

volume = {18},

number = {6-7},

pages = {708--722},

abstract = {Nuclear factor 90 (NF90) is a dual DNA- and RNA-binding protein expressed ubiquitously in mammalian cells, including monocytes. Here, to elucidate the function of NF90 in the immune response, we analyzed systematically its influence on gene expression programs in the human monocytic cell line THP-1 expressing normal or reduced NF90 levels. RNA sequencing analysis revealed many mRNAs showing differential abundance in NF90-silenced cells, many of them encoding proteins implicated in the response to immune stimuli and malaria infection. The transcription of some of them (e.g. TNF, LILRB1, and CCL2 mRNAs) was modulated by silencing NF90. Ribonucleoprotein immunoprecipitation (RIP) analysis further revealed that a subset of these mRNAs associated directly with NF90. To understand how NF90 influenced globally the immune response to malaria infection, lysates of red blood cells infected with Plasmodium falciparum (iRBC lysates) or uninfected/mock-infected (uRBC lysates) were used to treat THP-1 cells as a surrogate of malaria infection. NF90 affected the stability of a few target mRNAs, but influenced more generally the translation and secretion of the encoded cytokines after treatment with either uRBC or iRBC lysates. Taken together, these results indicate that NF90 contributes to repressing the immune response in cells responding to P. falciparum infection and suggest that NF90 can be a therapeutic target in malaria.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid30272251,

title = {Cooperative translational control of polymorphic BAFF by NF90 and miR-15a},

author = {M L Idda and V Lodde and W G McClusky and J L Martindale and X Yang and R Munk and M Steri and V Orru and A Mulas and F Cucca and K Abdelmohsen and M Gorospe},

year  = {2018},

date = {2018-12-01},

journal = {Nucleic Acids Res.},

volume = {46},

number = {22},

pages = {12040--12051},

abstract = {Polymorphisms in untranslated regions (UTRs) of disease-associated mRNAs can alter protein production. We recently identified a genetic variant in the 3'UTR of the TNFSF13B gene, encoding the cytokine BAFF (B-cell-activating factor), that generates an alternative polyadenylation site yielding a shorter, more actively translated variant, BAFF-var mRNA. Accordingly, individuals bearing the TNFSF13B variant had higher circulating BAFF and elevated risk of developing autoimmune diseases. Here, we investigated the molecular mechanisms controlling the enhanced translation of BAFF-var mRNA. We identified nuclear factor 90 (NF90, also known as ILF3) as an RNA-binding protein that bound preferentially the wild-type (BAFF-WT mRNA) but not BAFF-var mRNA in human monocytic leukemia THP-1 cells. NF90 selectively suppressed BAFF translation by recruiting miR-15a to the 3'UTR of BAFF-WT mRNA. Our results uncover a paradigm whereby an autoimmunity-causing BAFF polymorphism prevents NF90-mediated recruitment of microRNAs to suppress BAFF translation, raising the levels of disease-associated BAFF.},

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.},

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pubstate = {published},

tppubtype = {article}

}