[Extracellular chromosome 21--derived microRNAs in maternal circulation: evaluation of their diagnostic potential for screening of Down syndrome]. / Chromozom 21 - specifické mikroRNA v materské cirkulaci: zhodnocení jejich významu pro screening Downova syndromu u plodu.

OBJECTIVE: Initially, we focused on the detection of extracellular microRNAs in maternal circulation, whose genes are located on human chromosome 21 (miR-99a, let-7c, miR-125b-2, miR-155 and miR-802). Subsequently, we studied if plasmatic concentrations and/or expression profile of extracellular chromosome 21-derived microRNAs would distinguish between pregnancies bearing euploid foetuses and those affected with Down syndrome. DESIGN: Pilot study. SETTING: Division of Molecular Biology and Cell Pathology, Department of Gynaecology and Obstetrics, Third Faculty of Medicine, Charles University, Prague. METHODS: 12 women with normal course of gestation (mean 16.4 weeks, median 16.0 weeks), 12 pregnancies bearing Down syndrome foetus (mean 18.2 weeks, median 18.5 weeks) and 6 non-pregnant individuals were involved in the retrospective study. RNA enriched for small RNAs (including microRNAs) was isolated from 1ml of plasma sample. Consequently relevant microRNA was transcribed into cDNA using specific stem-loop primer and detected by specific real-time PCR assay. RESULTS: Commercial systems enabled reliable detection of 4 out of 5 extracellular chromosome 21-derived microRNAs (miR-99a, let-7c, miR-125b-2 and miR-155). Expression profile of extracellular miR-99a, miR-125b-2 and miR-155 was significantly higher in the cohort of pregnant women than in non-pregnant individuals. Also plasmatic levels of miR-99a and miR-125b-2 were significantly increased in pregnant women. Unfortunately, the concentrations and gene expression of extracellular chromosome 21-derived microRNAs (miR-99a, let-7c, miR-125b-2 and miR-155) did not differ between the cohorts of pregnancies bearing euploid foetuses and those affected with Down syndrome. CONCLUSION: Analysis of extracellular chromosome 21-derived microRNAs does not distinguish between pregnancies with euploid and aneuploid foetuses and has no benefit for screening programmes.

Influence of maternal hyperglycaemia on cord blood mononuclear cells in response to diabetes-associated autoantigens.

UNLABELLED: Perfect maternal diabetes compensation is crucial for the outcome of the baby. However, little is known how hyperglycaemia influences the specific immune response. Furthermore, babies of type 1 diabetes (T1D) mothers have less risk of development T1D than babies with a T1D father. This study aimed to analyze the effect of maternal hyperglycaemia on newborns with focus on the response to diabetes-associated autoantigens. POPULATIONS: (1) Newborns of T1D mothers split into groups according to maternal diabetes compensation during the 3rd trimester: perfect (n = 15) or acceptable (n = 25) compensation. (2) newborns with T1D father (n = 12) (3) newborns with a mother treated for either gestational or type 2 diabetes (n = 10) (4) control newborns (n = 25). Spontaneous as well as diabetes-associated autoantigen-stimulated production of 23 cytokines and chemokines were tested using protein microarray. In addition, the influence of glucose on cytokine and chemokine responsiveness was analyzed in vitro. The study groups differed in their spontaneous as well as stimulated cytokine and chemokine spectra. A prominent Th1 response (high IFN-gamma) from autoantigen stimulation was observed especially in babies of T1D fathers (P = 0.001) and also in mothers with perfect diabetes compensation during the 3rd trimester (P = 0.016) in comparison with control newborns. By contrast, cord blood mononuclear cells cultivated in vitro in high glucose concentration decreased the diabetogenic stimulated Th1 cytokine response. Maternal 'sweet' as well as 'autoimmune environment' may both lead to lower occurrence of T1D within their offspring. Further studies will reveal the exact immunological mechanism of this observation.

Reactivity to Helicobacter pylori antigens in patients suffering from thyroid gland autoimmunity.

The role of infection in autoimmunity is widely discussed. In this study we concentrated on relationship between HELICOBACTER PYLORI as a very important gastroduodenal pathogen and autoimmune thyroiditis (AT). Forty seven AT patients and 34 healthy controls were enrolled. They were split into: THP ( H.PYLORI positive patients, n=17), THN ( H.PYLORI negative patients, n=30), CP ( H.PYLORI positive controls, n=17) and CN groups ( H.PYLORI negative controls, n=17). By protein microarray we analysed production of 23 cytokines and chemokines prior and post stimulation with H.PYLORI lysate and its lipopolysaccharide (LPS). Reactivity to lysate as well as to bacterial LPS differed within groups. The lowest basal cytokine and chemokine production was observed in CN group but these subjects reacted significantly to specific stimulation by increasing IFN-gamma (in comparison with THP p=0.01 for LPS and p=0.004 for H.PYLORI lysate) and TGF-beta production (p=0.015 for LPS). In contrast, IL-10 and IL-5 were decreased in this group. In CP, THN and THP groups, we observed in general higher chemokine response. THP group increased proinflammatory IL-6 after specific stimulation as well (in comparison with CP p<0.0001 for LPS stimulation). We observed different "reactivity pattern" to H.PYLORI within groups with low basal cytokine and chemokine production in healthy H.PYLORI negative controls but with clear specific response in IFN-gamma and TGF-beta production in this group. Adequate immune reaction which is joined to appropriate immunoregulation leads to prevention of the chronic infection and on the other hand may prevent the development of "connected" diseases such as autoimmune.

Cord blood cytokine profile detection in neonates with T1D parents -- monitoring of cellular auto-reactivity using protein microarray.

Type 1 diabetes (T1D) is a great medical challenge and its incidence rises rapidly. T lymphocytes and their cytokine production are supposed to play a major role in T1D development. So far, there is no potent tool to recognize the early signs of cellular auto-reactivity which leads to beta-cell damage. The naïve immune system of the newborn (not yet influenced by external factors) can be used as an important model for T1D pathogenesis studies. Cord blood samples of 22 healthy neonates born at term to a diabetic parent (T1DR) and 15 newborns with no family history of any autoimmune disease (controls) were collected. Determination of 23 cytokines was performed before and after the stimulation with diabetogenic autoantigens using protein microarray. We observed lower basal production of all detected cytokines in the T1DR group - granulocyte/macrophage colony-stimulating factor (GM-CSF) (P = 0.025), growth regulated protein (GRO) (P = 0.002), GRO-alpha (P = 0.027), interleukin (IL)-1-alpha (P = 0.051), IL-3 (P = 0.008), IL-7 (P = 0.027), IL-8 (P = 0.042), monocyte chemoattractant proteins (MCP)-3 (P = 0.022), monokine-induced by IFN-gamma (MIG) (P = 0.034) and regulated upon activation normal T-cell express sequence (RANTES) (P = 0.004). Exclusively lower post-stimulative levels of G-CSF (P = 0.030) and GRO-alpha (P = 0.04) were observed in controls in comparison with the basal levels. A significant post-stimulative decrease in G-CSF (P = 0.030) and MCP-2 (P = 0.009) levels was observed in controls in comparison with T1DR neonates. We also observed the interesting impact of the risky genotype on the protein microarray results. Protein microarray seems to be a useful tool to characterize a risk pattern of the immune response for T1D also in newborns.

Acid sphingomyelinase deficiency. Phenotype variability with prevalence of intermediate phenotype in a series of twenty-five Czech and Slovak patients. A multi-approach study.

A multi-approach study in a series of 25 Czech and Slovak patients with acid sphingomyelinase deficiency revealed a broad phenotypic variability within Niemann-Pick disease types A and B. The clinical manifestation of only 9 patients fulfilled the historical classification: 5 with the rapidly progressive neurovisceral infantile type A and 4 with a slowly progressive visceral type B. Sixteen patients (64%) represented a hitherto scarcely documented 'intermediate type' (IT). Twelve patients showed a protracted neurovisceral course with overt or mild neurological symptoms, three a rapidly progressing fatal visceral affection with rudimentary neurological lesion. One patient died early from a severe visceral disease. The genotype in our patients was represented by 4 frameshift and 14 missense mutations. Six were novel (G166R, R228H, A241V, D251E, D278A, A595fsX601). The Q292K mutation (homoallelic, heteroallelic) was strongly associated with a protracted neurovisceral phenotype (10 of 12 cases). The sphingomyelin loading test in living fibroblasts resulted in total degradation from less than 2% in classical type A to 70-80% in classical type B. In the IT group it ranged from 5% to 49% in a 24 h chase. The liver storage showed three patterns: diffuse, zonal (centrolobular), and discrete submicroscopic. Our series showed a notable variability in both the neurological and visceral lesions as well as in their proportionality and synchrony, and demonstrates a continuum between the historical 'A' and 'B' phenotypes of ASM deficiency. This points to a broad phenotypic potential of ASM deficiency, suggesting the existence of still unknown factors independently controlling the storage level in the visceral and neuronal compartments. This report highlights the important position of the IT in the ASM deficiency phenotype classification. We define IT as a cluster of variants combining clinical features of both the classical types. The protracted neuronopathic variant with overt, borderline or subclinical neurology prevails and is important in view of future enzyme replacement therapy. It appears more common in central Europe. The visceral, rapidly progressing early fatal type has been recognized rarely so far.

In vitro autoreactivity against skin and synovial cells in patients with juvenile idiopathic and rheumatoid arthritis.

In the present study we compared specific lysis of various autologous target cells in patients with juvenile idiopathic arthritis JIA; n = 8) or rheumatoid arthritis RA; n = 17) with those of healthy controls (n = 15). (51)Cr-release cytotoxic assay with autologous peripheral blood mononuclear cells as effector cells was used. When compared with controls, effector cells of patients with JIA or RA were found to lyse significantly autologous synovial cells (p < 0.0005) and epidermal keratinocytes (p < 0.0005), however, no difference was found for autologous dermal fibroblasts.

[Medical genetics in reproductive medicine]. / Vyuzití lékarské genetiky v reprodukcní medicíne.

Reproductive genetics (RG) is another new field of medical genetics, integrated with reproductive medicine, assisted reproduction and developmental genetic. RG is closely linked to the perioconceptional prevention, perinatology, ultrasound and biochemical screening in the end of the first and beginning of the second trimesters. RG is based on the system of specialized genetic counseling, clinical cytogenetics, molecular cytogenetics and molecular genetics to provide prefertilization, preimplantation and classical prenatal diagnosis in the Ist to IIIrd trimesters. Thus, RG is part of the fetal medicine and therapy. The six years experience with RG is summarized. A system of the specialized health care, organized, if possible in one integrated center of RG and reproductive medicine (RM) is presented. Reproductive medicine provides all necessary clinical gynecological and andrological surveillance, with assisted reproduction and further obstetrical ultrasound examinations, including nuchal translucency measurements and 2D, 3D ultrasound, echocardiography examinations, if indicated, as well as the invasive method of prenatal diagnosis and perinatology care. Specialized genetic counseling and cytogenetic analysis, if indicated, should be offered to all partners with reproductive disorders as well as to oocyte donors. Chromosome anomalies are disclosed in 6% of men with abnormal sperm analysis as well as in women with severe reproductive disorders. In males with severe oligo, azoospermia, the sperm aneuploidy analysis by molecular cytogenetic methods is recommended. Advised is also the molecular genetic detection of Y chromosome microdeletions, which is detected in 9% of our azoospermic men with deletions in AZFb region. CFTR gene mutations and intron 8 and 10 polymorphism examination is provided not only in men with obstructive azoospermia (CBAVD), but also if severe oligospermy with less than 1 x 10(6) sperm/ml is detected. Molecular genetic analysis of thrombophilic mutations of factor II., V. (Leiden) and MTHFR gene in unexplained recurrent abortions and in cases with unsuccessful IVF is part of the diagnostic strategy. The population frequencies of carriers of mutations of factor II. (2.3%), factor V.-Leiden (5.7%) and MTHFR gene (38%) were determined. The laser biopsy of the first polar body and of blastomeres was introduced for FISH analysis of chromosome aneuploidies. Quantitative fluorescent PCR (QFPCR) detection is used for testing of the most frequent delta F508 CFTR gene mutation and the most frequent aneuploidies of chromosome 13, 18, 21, X and Y. QFPCR was successfully tested for male fetal sex examination from partially purified fetal cells in the maternal blood. The first trimester ultrasound and biochemical screening is recommended to all successful pregnancies after different IVF methods. If borderline levels of first trimester biochemical screening of PAPP-A protein and beta hCG are detected without pathological ultrasound findings, classical triple test of biochemical screening in 16th week of gestation is recommended. If pathological results of ultrasound and biochemical screening are disclosed, invasive prenatal genetic diagnosis is indicated as well as in pregnancies after ICSL, if there is not any obstetrical contraindication.

In vitro autoreactivity against skin in rheumatoid arthritis: are peripheral blood mononuclear cells of patients with rheumatoid arthritis able to lyze autologous keratinocytes?

An in vitro skin explant model was originally developed to predict the occurrence and severity of acute graft-versus-host disease in allogeneic hematopoietic stem cell transplants. In previous studies we reported that peripheral blood mononuclear cells of patients with rheumatoid arthritis were able to induce graft-versus-host-like histopathological changes when co-cultured in vitro with autologous skin explants. The aim of the present study was to verify if observed skin damage was really of autoimmune origin. Using a 51chromium release cytotoxic assay we found that peripheral blood mononuclear cells of patients lyzed autologous keratinocytes (n=5 patients with rheumatoid arthritis) but not autologous lymphoblasts (n=4 with rheumatoid arthritis, n=8 patients with juvenile idiopathic arthritis). No specific lysis of keratinocytes or lymphoblasts was observed in healthy controls (n=15). We hypothesize that autologous peripheral blood mononuclear cells might recognize similar autoantigen(s) expressed on epidermal cells, which gives rise to an autoimmune response in the synovium.

[Prenatal diagnosis of lysosomal enzymopathies in the Czech Republic]. / Prenatální diagnostika lysozomálních enzymopatií v Ceské Republice.

BACKGROUND: Prenatal diagnosisi represents the important fprm of prevention of the inherited metabolic diseases and its accessibility becomes the most effective assistance to involved families. The aim of the study was to introduce prenatal diagnosis of major inherited lysosomal disorders of the group of lipidoses, micopolysaccharidoses, glycoproteinoses, and mucolipidoses. METHODS AND RESULTS: Methodological approach is based on the activity estimation of the specific lysosomal hydrolases that are missing or inactive. Methods were extended by a set of supportive analyses, namely by ultrastructural identification of the lysosomal storage of the non-degraded substrate, DNA analysis showing mutation in the family or by biochemical analysis of the amniotic fluid. Uncultured cultured chorionic villi, cultured amniotic fluid cells yand samples of the amniotic fluid were examined. Altogether 17 pregnancies at risk for seven different lysosomal enzymopathies were followed: GM2 gangliosidosis (2 cases), Fabra disease (3 cases), Krabbe disease (1 case), Niemann-Pick disease type A (1 case), mucopolysaccharidosis I (5 cases), mucopolysaccharidosis II (4 cases), mucolipidosis II (I-cell disease) (1 case). Profound deficiency of enzyme activities (alpha-galactosidase A in fabry disease, galactocerebrosidase in Krabbe disease, alpha-iduronidase in mucopolysaccharidosis I) was identified in three pregnancies, which were terminated on the mother's decision. The diagnose was confirmed by the biochemical analysis of tissues of aborted foetuses. In two of them (Fabry disease, mucopolysaccharidosis I) ultrastructural sings of storage werw proved. In two cases the foetal heterozygote state was identified. In case at risk for Niemann-Pick disease type A, the diagnosis was confirmed also by DNA analysis. In the pregnancy at risk for Fabry disease, heterozygous state was confirmed indirectly according to the difference of alpha-galactosidase activities in cultured and uncultured cells. A set control values of enzyme activities in individual types of processed material (native and cultured chorionic villi, cultured amniocytes, and amniotic fluid supernatant) has been established. CONCLUSIONS: Inherited lysosomal enzymopathies represent important indication for prenatal diagnosis available now in our department. Condicio sine qua non is the biochemical or molecular genetic confirmation of diagnosis in the family involved.

Amniotic fluid 17-hydroxyprogesterone in early pregnancy.

The results of measurement of 17-hydroxyprogesterone (17-OH-P) in 125 samples of amniotic fluid (AF) from early amniocenteses are presented. The fetuses from all pregnancies studied were unaffected by congenital adrenal hyperphasia caused by 21-hydroxylase deficiency. The AF 17-OH-P level increases slightly but significantly between the 11th and 15th week of gestation, with a maximum in the 14th week. There is no difference between the values measured in male and female fetuses. The AF 17-OH-P levels from the early gestation were compared with those from the 16th-22nd week of pregnancy (published previously). The overall differences of AF 17-OH-P concentrations when considered in all gestational age groups in the whole period 12-22 weeks were statistically insignificant. Thus, the biochemical prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency and control of its early fetal treatment could be carried out starting from the end of the first trimester in the same way as at the later period of gestation.

[Strategies in prenatal diagnosis of cystic fibrosis after the introduction of DNA analysis. Initial experience]. / Strategie prenatální diagnostiky cystické fibrózy po zavedení analýzy DNA. Prvé zkusenosti.

The authors describe their experience with the prenatal genetic diagnosis of cystic fibrosis (CF), using DNA analysis in the first trimester of pregnancy in three families with a 25% risk of CF. The authors examined polymorphisms of probes J3.11, met D, met H, KM-19 and XV-2c. All families were fully informative when one or two probes were used. In two families the development of unaffected children--carriers of the gene for CF was proved. In one of these foetuses in the 17th and 21st week false pathological values of microvilillous enzymes were assessed. With regard to this possibility the authors do not recommend to supplement the DNA analysis in the first trimester by biochemical examination of amniotic fluid. The results were confirmed by delivery of unaffected children. In one family DNA analysis revealed the development of an unaffected homozygote, the pregnancy was, however, terminated by a miscarriage. In women with an increased risk of abortion the authors recommend therefore to make the molecular genetic examination during the second trimester from amniotic fluid cells.