Risk Minimization of Hemolytic Disease of the Fetus and Newborn Using Droplet Digital PCR Method for Accurate Fetal Genotype Assessment of RHD, KEL, and RHCE from Cell-Free Fetal DNA of Maternal Plasma.

The molecular pathology of hemolytic disease of the fetus and newborn (HDFN) is determined by different RHD, RHCE, and KEL genotypes and by blood group incompatibility between the mother and fetus that is caused by erythrocyte antigen presence/absence on the cell surface. In the Czech Republic, clinically significant antierythrocyte alloantibodies include anti-D, anti-K, anti C/c, and anti-E. Deletion of the RHD gene and then three single nucleotide polymorphisms in the RHCE and KEL genes (rs676785, rs609320, and rs8176058) are the most common. The aim of this study is to develop effective and precise monitoring of fetal genotypes from maternal plasma of these polymorphisms using droplet digital (dd)PCR. Fifty-three plasma DNA samples (from 10 to 18 weeks of gestation) were analyzed (10 RHD, 33 RHCE, and 10 KEL). The ddPCR methodology was validated on the basis of the already elaborated and established method of minisequencing and real-time PCR and with newborn phenotype confirmation. The results of ddPCR were in 100% agreement with minisequencing and real-time PCR and also with newborn phenotype. ddPCR can fully replace the reliable but more time-consuming method of minisequencing and real-time PCR RHD examination. Accurate and rapid noninvasive fetal genotyping minimizes the possibility of HDFN developing.

Two Reliable Methodical Approaches for Non-Invasive RHD Genotyping of a Fetus from Maternal Plasma.

Noninvasive fetal RHD genotyping is an important tool for predicting RhD incompatibility between a pregnant woman and a fetus. This study aimed to assess a methodological approach other than the commonly used one for noninvasive fetal RHD genotyping on a representative set of RhD-negative pregnant women. The methodology must be accurate, reliable, and broadly available for implementation into routine clinical practice. A total of 337 RhD-negative pregnant women from the Czech Republic region were tested in this study. The fetal RHD genotype was assessed using two methods: real-time PCR and endpoint quantitative fluorescent (QF) PCR. We used exon-7-specific primers from the RHD gene, along with internal controls. Plasma samples were analyzed and measured in four/two parallel reactions to determine the accuracy of the RHD genotyping. The RHD genotype was verified using DNA analysis from a newborn buccal swab. Both methods showed an excellent ability to predict the RHD genotype. Real-time PCR achieved its greatest accuracy of 98.6% (97.1% sensitivity and 100% specificity (95% CI)) if all four PCRs were positive/negative. The QF PCR method also achieved its greatest accuracy of 99.4% (100% sensitivity and 98.6% specificity (95% CI)) if all the measurements were positive/negative. Both real-time PCR and QF PCR were reliable methods for precisely assessing the fetal RHD allele from the plasma of RhD-negative pregnant women.

Clinical Potential of Effective Noninvasive Exclusion of KEL1-Positive Fetuses in KEL1-Negative Pregnant Women.

BACKGROUND: The clinical importance of assessing the fetal KEL genotype is to exclude 'K'-positive fetuses (genotype KEL1/KEL2) in 'K'-alloimmunized pregnant women (genotype KEL2/KEL2). Noninvasive assessment of the fetal KEL genotype is not yet available in the Czech Republic. OBJECTIVE: The aim of this study was to assess the fetal KEL1/KEL2 genotype from cell-free fetal DNA in the plasma of KEL2/KEL2 pregnant women. METHODS: The fetal genotype was assessed by minisequencing (a dilution series including control samples). A total of 138 pregnant women (between the 8th and 23rd gestational week) were tested by minisequencing. The fetal genotype was further verified by analysis of a buccal swab from the newborn. RESULTS: Minisequencing proved to be a reliable method. In 2.2% (3/138) of the examined women, plasma sample testing failed; 94.8% (128/135) had the KEL2/KEL2 genotype, and a total of 3.1% of fetuses (4/128) had the KEL1/KEL2 genotype. Sensitivity and specificity reached 100% (p < 0.0001). CONCLUSION: Minisequencing is a reliable method for the assessment of the fetal KEL1 allele from the plasma of KEL2/KEL2 pregnant women.

Association of STAT6 and ADAM33 single nucleotide polymorphisms with asthma bronchiale and IgE level and its possible epigenetic background.

BACKGROUND: ADAM33 and STAT6 belong to the candidate genes that have been commonly associated with asthma, bronchial hyperresponsiveness or IgE levels. Our objective was to assess the association of 11 SNPs of the ADAM33 and 6 of the STAT6 and their haplotypes with IgE levels and asthma. We also evaluated the possible role of parental origin of haplotypes on IgE levels. METHODS: We enrolled 109 children with asthma and 45 healthy controls. Genotyping was performed by TaqMan probes and confirmed by sequencing. Haplotype construction was based on the knowledge of parental genotypes and also inferred by using the EM algorithm and Bayes' theorem. RESULTS: None of the SNPs were associated with elevated IgE level or asthma. We found that the most frequent STAT6 haplotype ATTCAA (built from rs324012, rs324011, rs841718, rs3024974, rs3024974, rs4559 SNPs, respectively) was associated with elevated total IgE levels (P=0.01) and this haplotype was predominantly transmitted paternally (P<0.001). We compared our results with those of studies performed on German and Australian Caucasian populations and found that rs324011, rs3024974 and rs4559 SNPs in STAT6 should have a major effect on IgE levels. Therefore, we suggest the TCA haplotype alone (built from rs324011, rs3024974 and rs4559 SNPs, respectively) in STAT6 is associated with total IgE elevation. CONCLUSIONS: The influence of paternal origin of the STAT6 haplotype on IgE levels is surprising but the exact role of possible paternal imprinting in STAT6 regulation should be investigated and confirmed in future studies.

Efficacy and tolerance of enzymatic hydrolysed collagen (EHC) vs. glucosamine sulphate (GS) in the treatment of knee osteoarthritis (KOA).

This was a 13-week, multicentre, randomised, parallel, double-blind study. One hundred men and women volunteers aged ≥ 40 years with knee osteoarthritis (KOA) were randomised to once daily enzymatic hydrolysed collagen (EHC) 10 g or glucosamine sulphate (GS) 1.5 g for 90 consecutive days. Follow-up took place after two weeks and after one, two and three months. Primary [visual analogue scale (VAS), Western Ontario and McMaster Universities (WOMAC Index)] and secondary outcomes variables, assessed at weeks two, four, eight and 12, were KOA pain intensity measured by quadruple visual analogue scales in the target knee, the WOMAC total score index, patient's and investigator's global assessments of disease activity, joint assessment, use of rescue medication (ibuprofen 400 mg tablets) and assessment of Quality of Life index (SF-36 Questionnaire). Safety and tolerability were also evaluated. Clear improvement was observed in both joint pain and symptoms in patients with KOA treated with EHC (Colatech®) and significant differences were observed. Mean reductions from baseline for EHC 10 g daily and GS 1.5 g, respectively, were KOA pain intensity reduction in the target knee for Colatech® (p < 0.05): WOMAC index decrease ≤ 15 points at the last visit (day 90) for Colatech® in 16 patients (34.04%) (p < 0.05) and for glucosamine in six patients (13.04%); total score index for painful joints: Colatech® 1.6 (p < 0.05) and glucosamine 1.8; total score index for swollen joints: Colatech® 0.5 (p < 0.05) and glucosamine 0.7; patient's global assessment of efficacy as the sum of improvement good + ideal: 80.8% for Colatech® and 46.6% for glucosamine (p < 0.05). EHC (Colatech®) showed superior improvement over GS in the SF-36 Questionnaire in the Physical Health Index (42.0 for Colatech and 40.0 for glucosamine). The incidence of adverse events was similar in both groups. Both EHC and GS were well tolerated.

The efficacy and safety of diacerein in the treatment of painful osteoarthritis of the knee: a randomized, multicenter, double-blind, placebo-controlled study with primary end points at two months after the end of a three-month treatment period.

OBJECTIVE: To determine whether the efficacy of diacerein persists at 2 months after the end of a 3-month treatment period, compared with placebo, in patients with painful knee osteoarthritis (OA). METHODS: After a 1-week nonsteroidal antiinflammatory drug washout period, patients received either diacerein or placebo for 3 months, followed by an off-treatment period of 3 months to determine the carryover effects of the drug. Although patients were followed up through month 6, the primary efficacy end point was the percent change from baseline in pain (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] A) at month 5 (i.e., 2 months after the end of treatment) compared with placebo. The co-primary efficacy end point was the percent change from baseline in the total WOMAC score, also at month 5 versus placebo. RESULTS: Two hundred three patients were screened, and 168 patients with painful knee OA were randomized. One hundred sixty-five patients were analyzed in an intent-to-treat analysis. At month 5, diacerein showed statistically significant superiority versus placebo as assessed with both the WOMAC A (P < 0.0001) and the total WOMAC (P < 0.0001), demonstrating the carryover effect of the drug. This superiority was already evident from month 2 for pain (P = 0.001) and month 1 for total WOMAC (P = 0.0021). Diacerein was safe and well tolerated. No serious or previously undocumented adverse events were observed during the study. CONCLUSION: This is the first published study of a symptomatic slow-acting OA drug in which the time of assessment of the primary outcome end points was 2 months after the end of a 3-month treatment period. The results show that diacerein is safe and effective for the treatment of knee OA and has a long carryover effect.