1,721,123 research outputs found

    Mutation of FAS, XIAP, and UNC13D genes in a patient with a complex lymphoproliferative phenotype.

    No full text
    This article presents a case report for a child presenting with mixed clinical features of autoimmune lymphoproliferative syndrome (ALPS), familial hemophagocytic lymphohistiocytosis (FHL), and X-linked lymphoproliferative (XLP) disease. From 6 months, he exhibited splenomegaly and lymphoadenopathy and from 4 years, he showed recurrent severe autoimmune hemocytopenia and sepsislike bouts of fever, from which he eventually died at the age of 12. Intriguingly, the patient carried mutations in FAS, XIAP, and UNC13D genes, which are involved in ALPS, XLP disease, and FHL, respectively. These mutations were inherited from the mother, who had rheumatoid arthritis but no signs of ALPS. A role for other modifying genes was suggested by the finding that the healthy father exhibited defective Fas function, without mutation of the FAS gene, and had transmitted to the patient an osteopontin (OPN) gene variant previously associated with ALPS. Therefore, several genes might influence the disease outcome in this family. In vitro analyses revealed that the FAS and the XIAP mutations decreased expression of the corresponding proteins, and the UNC13D mutation decreased granule secretion and Munc interaction with Rab-27a. These findings suggest that overlap may exist between ALPS, FHL, and XLP disease, in accordance with the notion that FHL and XLP disease are due to defective natural killer (NK)/NK T-cell function, which involves Fas. Therefore, we propose that NK cell defects should be evaluated in patients with ALPS-like characteristics, and hematopoietic stem cell transplantation should be considered in individuals with severe refractory cytopenia and FHL-like manifestations

    The Glucocorticoid Receptor Polymorphism Landscape in Patients With Diamond Blackfan Anemia Reveals an Association Between Two Clinically Relevant Single Nucleotide Polymorphisms and Time to Diagnosis

    Full text link
    NR3C1, the gene encoding the glucocorticoid receptor, is polymorphic presenting numerous single nucleotide polymorphisms (SNPs) some of which are emerging as leading cause in the variability of manifestation and/or response to glucocorticoids in human diseases. Since 60–80% of patients with Diamond Blackfan anemia (DBA), an inherited pure red cell aplasia induced by mutations in ribosomal protein genes became transfusion independent upon treatment with glucocorticoids, we investigated whether clinically relevant NR3C1 SNPs are associated with disease manifestation in DBA. The eight SNPs rs10482605, rs10482616, rs7701443, rs6189/rs6190, rs860457, rs6198, rs6196, and rs33388/rs33389 were investigated in a cohort of 91 European DBA patients. Results were compared with those observed in healthy volunteers (n=37) or present in public genome databases of Italian and European populations. Although, cases vs. control analyses suggest that the frequency of some of the minor alleles is significantly altered in DBA patients with respect to healthy controls or to the Italian or other European registries, lack of consistency among the associations across different sets suggests that overall the frequency of these SNPs in DBA is not different from that of the general population. Demographic data (47 females and 31 males) and driver mutations (44 S and 29 L genes and eight no-known mutation) are known for 81 patients while glucocorticoid response is known, respectively, for 81 (36 responsive and 45 non-responsive) and age of disease onsets for 79 (55 before and 24 after 4months of age) patients. Neither gender nor leading mutations were associated with the minor alleles or with disease manifestation. In addition, none of the SNPs met the threshold in the response vs. non-responsive groups. However, two SNPs (rs6196 and rs860457) were enriched in patients manifesting the disease before 4months of age. Although the exact biomechanistical consequences of these SNPs are unknown, the fact that their configuration is consistent with that of regulatory regions suggests that they regulate changes in glucocorticoid response during ontogeny. This hypothesis was supported by phosphoproteomic profiling of erythroid cells expanded ex vivo indicating that glucocorticoids activate a ribosomal signature in cells from cord blood but not in those from adult blood, possibly providing a compensatory mechanism to the driving mutations observed in DBA before birth

    Severe iron overload in Blackfan-Diamond anemia: a case-control study

    No full text
    Chronic iron overload is a serious complication in transfusion-dependent patients. Few studies have addressed this issue in Diamond-Blackfan anemia (DBA). We describe a retrospective analysis of iron overload, and its related complications in 31 transfusion-dependent Italian DBA patients whose records included one or more evaluation of liver iron concentration (LIC) by means of noninvasive magnetic liver susceptometry with a superconductive quantum interference device (SQUID). This cohort is also matched with a group of transfusion-dependent beta-thalassemia major patients to look for differences. A severe iron overload was observed in 54% patients, especially among those inadequately chelated. The DBA patients displayed a significantly higher LIC than the regularly chelated beta-thalassemics. This difference may have been attributable to nonoptimal chelation (late onset, type, dose, prescription, and compliance), or an unknown biological mechanism that lead to an early severe iron overload. We therefore suggest that all transfusion patients should have an accurate record of their iron intake, a regular monitoring of iron overload, in order to start chelation when a critical transfusion load is reached, and to test the efficacy/compliance of chelation treatment. Physicians taking care of transfusion-dependent DBA patients must be concerned about the frequent and early complications such as cardiac toxicity
    corecore