Common Variable Immunodeficiency Caused by <Emphasis Type="Italic">FANC</Emphasis> Mutations

Common variable immunodeficiency (CVID) is the most common adult-onset primary antibody deficiency disease due to various causative genes. Several genes, which are known to be the cause of different diseases, have recently been reported as the cause of CVID in patients by performing whole exome sequencing (WES) analysis. Here, we found FANC gene mutations as a cause of adult-onset CVID in two patients. B cells were absent and CD4⁺ T cells were skewed toward CD45RO⁺ memory T cells. T-cell receptor excision circles (TRECs) and signal joint kappa-deleting recombination excision circles (sjKRECs) were undetectable in both patients. Both patients had no anemia, neutropenia, or thrombocytopenia. Using WES, we identified compound heterozygous mutations of FANCE in one patient and homozygous mutation of FANCA in another patient. The impaired function of FANC protein complex was confirmed by a monoubiquitination assay and by chromosome fragility test. We then performed several immunological evaluations including quantitative lymphocyte analysis and TRECs/sjKRECs analysis for 32 individuals with Fanconi anemia (FA). In total, 22 FA patients (68.8%) were found to have immunological abnormalities, suggesting that such immunological findings may be common in FA patients. These data indicate that FANC mutations are involved in impaired lymphogenesis probably by the accumulation of DNA replication stress, leading to CVID. It is important to diagnose FA because it drastically changes clinical management. We propose that FANC mutations can cause isolated immunodeficiency in addition to bone marrow failure and malignancy.     

Functional polymorphisms in <Emphasis Type="Italic">XRCC</Emphasis>-<Emphasis Type="Italic">1</Emphasis> and <Emphasis Type="Italic">APE</Emphasis>-<Emphasis Type="Italic">1</Emphasis> contribute to increased apoptosis and risk of ulcerative colitis

Objective  

The present study was designed to investigate the role of X-ray cross-complementing group 1 (XRCC1) and apurinic/apyrimidinic endonuclease 1 (APE1) polymorphisms in apoptosis and the risk of ulcerative colitis (UC).     

<Emphasis Type="Italic">Pepo aphid</Emphasis>-<Emphasis Type="Italic">borne yellows virus</Emphasis>: a new species in the genus <Emphasis Type="Italic">Polerovirus</Emphasis>

Pepo aphid-borne yellows virus (PABYV) has been proposed as a putative representative of a new species in the genus Polerovirus in the family Luteoviridae. The genomes of two South African (SA) isolates of cucurbit-infecting PABYV were described in this record. Total RNA, extracted from a pattypan (Cucurbita pepo L.) and a baby marrow (C. pepo L.) leaf samples, was subjected to next-generation sequencing (NGS) on the HiSeq Illumina platform. Sanger sequencing was subsequently used to authenticate the integrity of PABYV’s genome generated from de novo assembly of the NGS data. PABYV genome of SA isolates consists of 5813 nucleotides and displays an organisation typical of poleroviruses. Genome sequence comparisons of the SA PABYV isolates to other poleroviruses support the classification of PABYV as a new species in the genus Polerovirus. Recombination analyses showed that PABYV and Cucurbit aphid-borne yellows virus (CABYV) shared the same ancestor for the genome part situated between breaking points. Phylogenetic analyses of the RNA-dependent RNA polymerase and the coat protein genes showed that SA PABYV isolates shared distant relationship with CABYV and Suakwa aphid-borne yellows virus. Based on our results, we propose that PABYV is a distinct species in the genus Polerovirus.     

Cercarial shedding from <Emphasis Type="Italic">Galba</Emphasis><Emphasis Type="Italic">truncatula</Emphasis> infected with <Emphasis Type="Italic">Fasciola</Emphasis><Emphasis Type="Italic">gigantica</Emphasis> of distinct geographic origins

Galba truncatula snails were experimentally infected with either of two different isolates of Fasciola gigantica, originating from Egypt or China, to determine the influence of these isolates on the characteristics of snail infections. The survival rates of G. truncatula on day 30 post-exposure were 90.0% and 60.2% in the Egyptian and Chinese groups, respectively. The frequency of cercaria-shedding snails within the Egyptian group was 79.8%, whereas in the Chinese group it was 22.4%. The parasite origin had a significant effect on the durations of the prepatent and patent periods. The mean number of cercariae shed from the Egyptian group was significantly greater than that shed from the Chinese group (a mean of 275.5 per cercaria-shedding snail compared with 29.0). These results could be explained by the fact that G. truncatula might be a natural intermediate host for F. gigantica in Egypt, and the greater adaptability of the Egyptian miracidia of F. gigantica to unusual snail hosts. These results demonstrate the influence of the geographic origin of the parasite on the success of trematodes infecting snails.     

Associations between <Emphasis Type="Italic">interleukin</Emphasis>-<Emphasis Type="Italic">23R</Emphasis> polymorphisms and ankylosing spondylitis susceptibility: a meta-analysis

Objective  

The aim of this study was to determine whether interleukin-23R (IL-23R) polymorphisms confer susceptibility to ankylosing spondylitis (AS).     

Mutational Analysis of Human BAFF Receptor <Emphasis Type="Italic">TNFRSF13C (BAFF-R)</Emphasis> in Patients with Common Variable Immunodeficiency

BAFF receptor (BAFF-R/BR3/TNFRSF13C) is a recently identified molecule that specifically binds BLyS, a protein belonging to the tumor necrosis factor (TNF) family, and is involved in survival and maturation of B cells. Recent studies have demonstrated that mice defective in BAFF-R gene exhibit an altered profile of the B cell pool, a phenotype observed in BLyS knockout mice as well. These features suggest that mutations in this gene may result in humoral immunodeficiency. To test this hypothesis, we sequenced the BAFF-R gene in 48 patients with common variable immunodeficiency (CVID) along with 57 healthy controls. We have identified three novel variants present at the heterozygous state leading to amino acid substitutions, and have also confirmed the existence of a previously reported intronic variant. The hereby described novel variants were also present in healthy controls and in the healthy patients’ parents. These variants do not affect the expression of BAFF-R neither at the mRNA nor at the protein level, suggesting that these variants represent novel polymorphic variants of the BAFF-R gene.     

Persistent Colonization of Nine Cystic Fibrosis Patients with an<Emphasis Type="Italic"> Achromobacter</Emphasis> (<Emphasis Type="Italic">Alcaligenes</Emphasis>)<Emphasis Type="Italic"> xylosoxidans</Emphasis> Clone

The present study was conducted to investigate the increasing incidence of Achromobacter (previously Alcaligenes) xylosoxidans isolates being recovered from sputum samples of cystic fibrosis patients at a cystic fibrosis department for adults in Athens, Greece. During the 1-year study period, a total of 34 isolates were detected persistently in 9 of 71 cystic fibrosis patients. The isolates exhibited resistance to multiple antimicrobial agents. Isolates that were recovered repeatedly from each patient exhibited identical macrorestriction profiles with pulsed-field gel electrophoresis, indicating that the same strain persisted in the lungs of these patients. Isolates from five of the patients were genetically related, suggesting a common-source outbreak of Achromobacter xylosoxidans colonization or infection.     

Cysteine proteinases from promastigotes of <Emphasis Type="Italic">Leishmania</Emphasis> (<Emphasis Type="Italic">Viannia</Emphasis>) <Emphasis Type="Italic">braziliensis</Emphasis>

Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of 63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection.     

<Emphasis Type="Italic">Slc11a1</Emphasis> (<Emphasis Type="Italic">Nramp</Emphasis>-<Emphasis Type="Italic">1</Emphasis>) gene modulates immune-inflammation genes in macrophages during pristane-induced arthritis in mice

Objective and design

Pristane-induced arthritis (PIA) in AIRmax mice homozygous for Slc11a1 R and S alleles was used to characterize the influence of Slc11a1 gene polymorphism on immune responses during disease manifestation. Previous reports demonstrated that the presence of the Slc11a1 S allele increased the incidence and severity of PIA in AIRmax ^SS , suggesting that this gene could interact with inflammatory loci to modulate PIA. We investigated the effects of Slc11a1 alleles on the activation of phagocytes during PIA.

Treatment

Mice were injected intraperitoneally with two doses of 0.5 mL of mineral oil pristane at 60-day intervals. Arthritis development was accompanied for 180 days.

Results

AIRmax ^SS mice showed differential peritoneal macrophage gene expression profiles during PIA, with higher expression and production of H₂O₂, NO, IL-1β, IL-6, TNF-α, and several chemokines. The presence of the Slc11a1 R allele, on the other hand, diminished the intensity of macrophage activation, restricting arthritis development.

Conclusion

Our data demonstrated the fine-tuning roles of Slc11a1 alleles modulating macrophage activation, and consequent PIA susceptibility, in those mouse lines.

     

Genetic reassortment between high-virulent and low-virulent <Emphasis Type="Italic">Dobrava</Emphasis>-<Emphasis Type="Italic">Belgrade virus</Emphasis> strains

The tri-segmented RNA genome of hantaviruses facilitates genetic reassortment by segment swapping when cells are co-infected with different virus strains. We found efficient in vitro reassortment between members of two different genetic lineages of the Dobrava-Belgrade virus species, the weakly virulent DOBV-Aa and highly virulent DOBV-Af. In all reassortants, S and L segments originated from the same parental strain, and only the M segment was exchanged. To identify functional differences between the parental strains DOBV-Aa and DOBV-Af in cell culture and to compare them with the reassortants, we studied elements of the innate immunity in virus-infected cells. The contrasting phenotypes of the parental viruses were maintained by the reassortants carrying the respective S and L segments of the parental virus and were not influenced by the origin of the M segment.     

<Emphasis Type="Italic">P</Emphasis>. <Emphasis Type="Italic">aeruginosa</Emphasis> Biofilms in CF Infection

Pseudomonas aeruginosa is an opportunistic pathogen of immunocompromised hosts. In cystic fibrosis (CF), P. aeruginosa causes acute and chronic lung infections that result in significant morbidity and mortality. P. aeruginosa possesses several traits that contribute to its ability to colonize and persist in acute and chronic infections. These include high resistance to antimicrobials, ability to form biofilms, plethora of virulence products, and metabolic versatility. In P. aeruginosa, a cell-to-cell communication process termed quorum sensing (QS) regulates many of these factors that contribute to its pathogenesis. Recent evidence suggests that the CF lung environment presents a specialized niche for P. aeruginosa. The relationship of P. aeruginosa QS, biofilm formation, and the CF lung environment is discussed.     

Redescription of <Emphasis Type="Italic">Lemuricola</Emphasis> (<Emphasis Type="Italic">Madoxyuris</Emphasis>) <Emphasis Type="Italic">bauchoti</Emphasis> (Nematoda,Oxyuridae) from <Emphasis Type="Italic">Lemur catta</Emphasis> in Madagascar

Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini hosts will only be proven when additional records fill in the gaps in their distribution.     

Correlation of <Emphasis Type="Italic">TLR4</Emphasis> and <Emphasis Type="Italic">KLF7</Emphasis> in Inflammation Induced by Obesity

Objective Recent studies have revealed a link between toll-like receptors (TLRs), Kruppel-like factors (KLFs), and the adipose tissue inflammation associated with obesity. TLR4 is associated with chronic inflammation in obesity. KLF7 is known to play an important role in the differentiation of adipocytes, but its role in visceral adipose tissue inflammation has not yet been investigated. Thus, the objective of this study was to determine the correlation of TLR4 and KLF7 in inflammation induced by obesity. Methods A total of 32 Wistar male rat subjects were fed in the center for experimental animals of Shihezi University. The rats were divided into normal control (NC) and high-fat diet (HFD) group. Surgical instruments were used to collect rats’ visceral adipose tissue samples in the 10th week after HFD feeding. Ninety-five Uygur subjects between 20 and 90 years old were enrolled in the present study. The subjects were divided into two groups: the normal control group (NC, 18.0 kg/m²?≤?BMI?≤?23.9 kg/m², n?=?50) and the obesity group (OB, BMI?≥?28 kg/m², n?=?45), and visceral adipose tissue was collected from the subjects. Anthropometric and clinical parameters were measured using standard procedures; biochemical indices were detected using the glucose oxidase-peroxidase method and a standardized automatic biochemistry analyzer; the plasma levels of inflammatory factors and adipocytokines were measured by enzyme-linked immunosorbent assay (ELISA); the mRNA and protein expression levels of key genes involved in the inflammatory signaling pathway were measured by real-time PCR and Western blot. Results In rats, compared with the NC group, the weight, Lee’s index, waist circumference, visceral fat mass, and the plasma level of Glu, TG, FFA, and TNF-α were higher in the HFD group, while the plasma levels of LPT and APN were significantly lower in the HFD group in the 10th week. Furthermore, compared with the NC group, visceral adipose tissue’s mRNA expression levels of TLR4, KLF7, and SRC were higher in the HFD group, and KLF7 was significantly positively correlated with LDL, TLR4, SRC, and IL-6 (P?<?0.05). Meanwhile, in the Uygur population, the plasma levels of TG, LDL, and TNF-α in the OB group were significantly higher than those in the NC group (P?<?0.05). Moreover, compared with the NC group, visceral adipose tissue’s mRNA expression levels of TLR4, KLF7, and SRC were significantly higher in the OB group (P?<?0.05), and KLF7 was significantly positively correlated with TC, TLR4, MYD88, SRC, and IL-6 (P?<?0.05); the protein expression levels of TLR4 and KLF7 were significantly higher than those in the NC group (P?<?0.05). Conclusion Higher expression of TLR4 and KLF7 may play a vital role in the process of inflammation induced by obesity in visceral adipose tissue.     

Repeat induced point mutation in two asexual fungi, <Emphasis Type="Italic">Aspergillus niger</Emphasis> and <Emphasis Type="Italic">Penicillium </Emphasis><Emphasis Type="Italic">chrysogenum</Emphasis>

Repeat induced point mutation (RIP) is a gene silencing mechanism present in fungal genomes. During RIP, duplicated sequences are efficiently and irreversibly mutated by transitions from C:G to T:A. For the first time, we have identified traces of RIP in transposable elements of Aspergillus niger and Penicillium chrysogenum, two biotechnologically relevant fungi. We found that RIP in P. chrysogenum has affected a large set of sequences, which also contain other mutations. On the other hand, RIP in A. niger is limited to only few sequences, but literally all mutations are RIP-like. Surprisingly, RIP occurred only in transposon sequences that have disrupted open reading frames in A. niger, a phenomenon not yet reported for other fungi. In both fungal species, we identified two sequences with strong sequence similarity to Neurospora crassa RID. RID is a putative DNA methyltransferase and the only known enzyme involved in the RIP process. Our findings suggest that both A. niger and P. chrysogenum either had a sexual past or have a sexual potential. These findings have important implications for future strain development of these fungi.     

Selective activity of extracts of <Emphasis Type="Italic">Margaritaria discoidea</Emphasis> and <Emphasis Type="Italic">Homalium africanum</Emphasis> on <Emphasis Type="Italic">Onchocerca ochengi</Emphasis>

Background  

The current treatment of onchocerciasis relies on the use of ivermectin which is only microfilaricidal and for which resistant parasite strains of veterinary importance are increasingly being detected. In the search for novel filaricides and alternative medicines, we investigated the selective activity of crude extracts of Margaritaria discoidea and Homalium africanum on Onchocerca ochengi, a model parasite for O. volvulus. These plants are used to treat the disease in North West Cameroon.     

<Emphasis Type="Italic">Helicobacter pylori</Emphasis> and <Emphasis Type="Italic">cagA</Emphasis> and <Emphasis Type="Italic">vacA</Emphasis> gene status in children from Brazil with chronic gastritis

Helicobacter pylori has been shown to be strongly associated with chronic gastritis, gastric and duodenal ulceration, and is a risk factor for gastric carcinoma. Histology, urease, culture, and polymerase chain reaction have been employed as for H. pylori diagnostic methods, pre and post treatment or during follow-up of dyspeptic adult individuals referred for endoscopy. In order to obtain a more-sensitive and specific method for H. pylori detection, we evaluated gastric body and antrum biopsies of 134 consecutive Brazilian consecutive dyspeptic children aged 1-16 years by rapid urease test, histology and polymerase chain reaction using two pairs of oligonucleotides. Our results indicated that polymerase chain reaction with Southern blotting and hybridization with specific chemiluminescent probes increased the number of positive H. pylori patients by 35%. The genotyping of H. pylori strains directly from gastric biopsy using the same nucleic acid methodology revealed that there is no association of chronic gastritis in our infant patients with vacA s1 and the presence of the cagA gene. These data suggest an initial infection of children with normal mucosa and probably others factors than vacA s1 genotype or the presence of the cagA gene are associated with the onset of gastric disease. Altogether, our results reinforce the need for using more sensitive diagnostic methods in order to understand the role of H. pylori in the genesis of gastric disease in children and its progression in adults.