Evaluation of the FCGR2B polymorphism in children with immune thrombocytopenia.

BACKGROUND: Childhood immune thrombocytopenia (ITP) is an immune-mediated disease characterized by an isolated low platelet count. Pathogenesis of ITP is complex but many patients have platelet specific autoantibodies leading to accelerated clearance of opsonized platelets by Fc-gamma receptor (FcγR) bearing phagocytes, particularly in the spleen. In humans, there are three main types of Fcγ receptors: high-affinity FcγRI and low-affinity FcγRII and FcγRIII. About FcγRII, genetic variation of FCGR2B is associated with response to IVIg treatment in patients with Kawasaki disease and ITP. OBJECTIVE: We used a TaqMAMA genotyping assay for detection of rs1050501 FCGR2B polymorphism in children with chronic ITP. STUDY DESIGN: A SNP rs1050501 (GenBank access number NG_023318.1, Homo sapiens Fc fragment of IgG receptor IIb (FCGR2B)) on chromosome 1 showing a T/C transition in position 15894 on FCGRB2 gene was chosen in this study. A series of experiments was conducted to evaluate the performance of the FCGR2B-MAMAPCR real time on a QuantStudio™ 5 Real-Time PCR System as compared to the 7500 Real-Time PCR System. RESULTS: Background noise, Genotypes discrimination, Variability, Allele and genotype frequencies and concordance were obtained. About clinical validation, all 60 samples collected from chronic ITP patients were analyzed. We found 53 on the 60 patients (88.4%) were homozygotes (52 TT and 1 CC) and 7/60 (11.6%) heterozygotes (TC). CONCLUSIONS: The ability of the FCGR2B-MAMAPCR real time to detect rs1050501 FCGR2B polymorphism in children with chronic ITP on the QuantStudio™ 5 System is comparable to that on the 7500 System.

Comparison of methods for isolating fungal DNA.

OBJECTIVES: The main aim of this work was to compare the methods of DNA isolation in the moulds of genus Mucorales with special regard to the amount and purity of the DNA acquired. The acquired DNA was then amplified by specific real-time PCR. DESIGN: Five DNA extraction procedures were carried out in a Class 2 Biosafety cabinet in a dedicated room with suitable biosafety precautions and appropriate biowaste disposal methods. A total of 6 Mucorales clinical strains were used. RESULTS: From the viewpoint of concentration and purity, methods A shown abundant amount of fungal DNA whereas methods E report a pure fungal DNA with R260/280 of 1.7 near the optimal 1.8. The DNA quantity reach statistically difference at ANOVA test with p value 0.0005. CONCLUSION: Overall, the E method was the most efficient method in the extraction of DNA from fungal cultures compared to the other methods considering time, cost, technical expertise, and instrumentation. Use of this assay will allow researchers to obtain DNA from fungi quickly for use in molecular assays.

Bufavirus, Cosavirus, and Salivirus in Diarrheal Italian Infants.

Three newly discovered viruses have been recently described in diarrheal patients: Cosavirus (CosV) and Salivirus (SalV), 2 picornaviruses, and bufavirus (BuV), a parvovirus. The detection rate and the role of these viruses remain to be established in acute gastroenteritis (AGE) in diarrheal Italian infants. From November 2016 to November 2017, stool samples were collected from 160 children <5 years old suffering from AGE and attending the Children's Hospital in Turin, Italy. During the study period, 1 (0.5%) sample was positive for 1 of the 3 investigated viruses: 0 (0%) CosV, 1 (0.5%) SalV, and 0 (0%) BuV, whereas 42 (26.0%) children were infected with rotavirus and 2 (1%) with adenovirus. No mixed infections involving the 3 viruses were found. Although these viruses are suspected to be responsible for AGE in children, our data showed that this association was uncertain. Therefore, further studies with large cohorts of healthy and diarrheal children will be needed to evaluate their clinical role in AGE.

Modulation of human endogenous retroviruses -H, -W and -K transcription by microbes.

The human endogenous retroviruses (HERVs) are endogenous retroviruses that are inserted into the germ cell DNA of humans over 30 million years ago. Using real-time RT-PCR we describe HERV modulation by commensal microbes in the human gut. Infants, exclusively or predominant breast milk feeding, less than 12 weeks of age, during bacteria gut colonization, were assessed for eligibility. Our data demonstrate that the colonization with commensal microbes, in particular, Bifidobacterium spp., of the gut causes modulation of HERVs.