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BACKGROUND: Postzygotic de novo mutations lead to the phenomenon of gene mosaicism. The 3 main types are called somatic, gonadal, and gonosomal mosaicism, which differ in terms of the body distribution of postzygotic mutations. Mosaicism has been reported occasionally in patients with primary immunodeficiency diseases (PIDs) since the early 1990s, but its real involvement has not been systematically addressed. OBJECTIVE: We sought to investigate the incidence of gene mosaicism in patients with PIDs. METHODS: The amplicon-based deep sequencing method was used in the 3 parts of the study that establish (1) the allele frequency of germline variants (n = 100), (2) the incidence of parental gonosomal mosaicism in families with PIDs with de novo mutations (n = 92), and (3) the incidence of mosaicism in families with PIDs with moderate-to-high suspicion of gene mosaicism (n = 36). Additional investigations evaluated body distribution of postzygotic mutations, their stability over time, and their characteristics. RESULTS: The range of allele frequency (44.1% to 55.6%) was established for germline variants. Those with minor allele frequencies of less than 44.1% were assumed to be postzygotic. Mosaicism was detected in 30 (23.4%) of 128 families with PIDs, with a variable minor allele frequency (0.8% to 40.5%). Parental gonosomal mosaicism was detected in 6 (6.5%) of 92 families with de novo mutations, and a high incidence of mosaicism (63.9%) was detected among families with moderate-to-high suspicion of gene mosaicism. In most analyzed cases mosaicism was found to be both uniformly distributed and stable over time. CONCLUSION: This study represents the largest performed to date to investigate mosaicism in patients with PIDs, revealing that it affects approximately 25% of enrolled families. Our results might have serious consequences regarding treatment and genetic counseling and reinforce the use of next-generation sequencing-based methods in the routine analyses of PIDs. ispartof: JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY vol:143 issue:1 pages:359-368 ispartof: location:United States status: published

Objective Gain-of-function NLRP3 mutations cause cryopyrin-associated periodic syndrome (CAPS), with gene mosaicism playing a relevant role in the pathogenesis. This study was undertaken to characterize the genetic cause underlying late-onset but otherwise typical CAPS. Methods We studied a 64-year-old patient who presented with recurrent episodes of urticaria-like rash, fever, conjunctivitis, and oligoarthritis at age 56 years. DNA was extracted from both unfractionated blood and isolated leukocyte and CD34+ subpopulations. Genetic studies were performed using both the Sanger method of DNA sequencing and next-generation sequencing (NGS) methods. In vitro and ex vivo analyses were performed to determine the consequences that the presence of the variant have in the normal structure or function of the protein of the detected variant. Results NGS analyses revealed the novel p.Gln636Glu NLRP3 variant in unfractionated blood, with an allele frequency (18.4%) compatible with gene mosaicism. Sanger sequence chromatograms revealed a small peak corresponding to the variant allele. Amplicon-based deep sequencing revealed somatic NLRP3 mosaicism restricted to myeloid cells (31.8% in monocytes, 24.6% in neutrophils, and 11.2% in circulating CD34+ common myeloid progenitor cells) and its complete absence in lymphoid cells. Functional analyses confirmed the gain-of-function behavior of the gene variant and hyperactivity of the NLRP3 inflammasome in the patient. Treatment with anakinra resulted in good control of the disease. Conclusion We identified the novel gain-of-function p.Gln636Glu NLRP3 mutation, which was detected as a somatic mutation restricted to myeloid cells, as the cause of late-onset but otherwise typical CAPS. Our results expand the diversity of CAPS toward milder phenotypes than previously reported, including those starting during adulthood.

Gain-of-function NLRP3 mutations cause cryopyrin-associated periodic syndrome (CAPS), with gene mosaicism playing a relevant role in the pathogenesis. This study was undertaken to characterize the genetic cause underlying late-onset but otherwise typical CAPS.We studied a 64-year-old patient who presented with recurrent episodes of urticaria-like rash, fever, conjunctivitis, and oligoarthritis at age 56 years. DNA was extracted from both unfractionated blood and isolated leukocyte and CD34+ subpopulations. Genetic studies were performed using both the Sanger method of DNA sequencing and next-generation sequencing (NGS) methods. In vitro and ex vivo analyses were performed to determine the consequences that the presence of the variant have in the normal structure or function of the protein of the detected variant.NGS analyses revealed the novel p.Gln636Glu NLRP3 variant in unfractionated blood, with an allele frequency (18.4%) compatible with gene mosaicism. Sanger sequence chromatograms revealed a small peak corresponding to the variant allele. Amplicon-based deep sequencing revealed somatic NLRP3 mosaicism restricted to myeloid cells (31.8% in monocytes, 24.6% in neutrophils, and 11.2% in circulating CD34+ common myeloid progenitor cells) and its complete absence in lymphoid cells. Functional analyses confirmed the gain-of-function behavior of the gene variant and hyperactivity of the NLRP3 inflammasome in the patient. Treatment with anakinra resulted in good control of the disease.We identified the novel gain-of-function p.Gln636Glu NLRP3 mutation, which was detected as a somatic mutation restricted to myeloid cells, as the cause of late-onset but otherwise typical CAPS. Our results expand the diversity of CAPS toward milder phenotypes than previously reported, including those starting during adulthood.

The existence of strains of Vibrio vulnificus serovar E that are avirulent for eels is reported in this work. These isolates were recovered from water and oysters and differed from eel virulent strains in (i) fermentation and utilization of mannitol, (ii) ribotyping after Hin dIII digestion, and (iii) susceptibility to eel serum. Lipopolysaccharide of these strains lacked the highest molecular weight immunoreactive bands, which are probably involved in serum resistance.

Birds develop rapidly compared with other vertebrates, and it has been proposed that such rapid development serves to minimize the period of exposure to predators of eggs and nestlings. Evidence is, however, scant. We test the proposition that nest predation has been an important selective factor in the evolution of the rapid developmental rates characteristic of altricial birds. We compare the incubation and nestling periods of altrical land birds from islands that lack native mammalian and reptilian nest predators with those of phylogenetically related species from areas with predators. We show that open-nesting native species from islands take longer to hatch and fledge than related species from continents, controlling for body mass. In contrast, species that have been recently introduced to islands have similar incubation and nestling periods there compared to those in their region of origin. In addition, we show that statistically different regression equations describe the interspecific allometric relationships be- tween incubation and nestling period and body mass in hole-nesting and open-nesting species, the latter of which presumably face higher predation pressure. We confirm that, in relation to body mass, hole-nesting species develop more slowly. We conclude that predation has been an important selective factor in the evolution of developmental rates in altricial birds.

The objective of this work is to analyze the survival of infliximab, etanercept and adalimumab in patients who have switched among tumor necrosis factor (TNF) antagonists for the treatment of chronic arthritis. BIOBADASER is a national registry of patients with different forms of chronic arthritis who are treated with biologics. Using this registry, we have analyzed patient switching of TNF antagonists. The cumulative discontinuation rate was calculated using the actuarial method. The log-rank test was used to compare survival curves, and Cox regression models were used to assess independent factors associated with discontinuing medication. Between February 2000 and September 2004, 4,706 patients were registered in BIOBADASER, of whom 68% had rheumatoid arthritis, 11% ankylosing spondylitis, 10% psoriatic arthritis, and 11% other forms of chronic arthritis. One- and two-year drug survival rates of the TNF antagonist were 0.83 and 0.75, respectively. There were 488 patients treated with more than one TNF antagonist. In this situation, survival of the second TNF antagonist decreased to 0.68 and 0.60 at 1 and 2 years, respectively. Survival was better in patients replacing the first TNF antagonist because of adverse events (hazard ratio (HR) for discontinuation 0.55 (95% confidence interval (CI), 0.34-0.84)), and worse in patients older than 60 years (HR 1.10 (95% CI 0.97-2.49)) or who were treated with infliximab (HR 3.22 (95% CI 2.13-4.87)). In summary, in patients who require continuous therapy and have failed to respond to a TNF antagonist, replacement with a different TNF antagonist may be of use under certain situations. This issue will deserve continuous reassessment with the arrival of new medications. © 2006 Gomez-Reino and Loreto Carmona; licensee BioMed Central Ltd.

9 páginas, 3 figuras, 5 tablas., A strain of the marine rotifer Synchaeta cecilia valentina, isolated from 'El Hondo de Elche', a Spanish Mediterranean coastal lagoon, was cultured in the laboratory in 20 ml test tubes, at 20°C and 25 ppt salinity and fed with the algae Tetraselmis sp., T. chuii, Cryptomonas sp., Rhodomonas salina and R. baltica. The effects of these 5 algal diets and 3 food levels (2.1, 3.2 and 4.2 µg ml-1 dry wt) on life history traits of this rotifer were studied in life tables performed with replicated individual cultures of 1 ml, at the temperature and salinity mentioned above. Algal diet had a significant effect on both average lifespan (LS) and net reproductive rate (R0), but food concentration only had an effect on R0. Tetraselmis sp. provided the best results: LS ranging from 4.4 to 6 d, R0 from 10.9 to 12.8 offsping female-1, and intrinsic growth rate (r) from 0.84 to 1.12 d-1. S. cecilia valentina also grew with the remainder of the algae, except with R. baltica. With this alga the rotifer grew only in 500 ml cultures performed at a higher food concentration (5.55 µg ml-1 dry wt). The effect of the algal diet on the fatty acid composition of the rotifers was analysed to infer its nutritional value according to the changes induced by diet. Saturated fatty acids made up 34 to 40% of total fatty acids, whereas monoenes accounted for 15 to 23%, and polyunsaturated fatty acids constituted 20 to 29%. Main fatty acids were: 16:0 (which ranged from 17 to 22%), 18:0 (10 to 12%), and 18:1 (8.5 to 12%). In certain algal treatments (both Tetraselmis species), the linolenic acid 18:3n-3 was moderately abundant (5 to 9%). Eicosapentaenoic acid, 20:5n-3, was markedly lower in rotifers fed with R. baltica (less than 3%), whereas docosahexaenoic acid, 22:6n-3, was found in a higher proportion in Cryptomonas sp. (4.9%) and R. salina (3.4%) treatments. The nutritional value deduced from the lipid composition was similar to that reported in the literature for other rotifers such as Brachionus plicatilis., This study was supported by Spanish Culture and Education Ministry, project MAR98-0871-C02-01/02.