Cervical trophoblasts for non-invasive single-cell genotyping and prenatal diagnosis.

OBJECTIVE: We aimed at developing a method to recover trophoblastic cells from the cervix through a completely non-invasive approach and obtaining a genetic proof of their fetal nature implying that they can be used for non-invasive prenatal diagnosis (NIPD). METHODS: We studied obstetrical samples from 21 pregnant women between 8 and 12 weeks of gestation scheduled for chorionic villus sampling or undergoing elective termination of pregnancy. A cytobrush was used to extract cells from the external parts of the cervix and transferred to 10 ml of preservative solution. Cells were layered on filters with 8 microns pores using the ISET system (Isolation by SizE of Tumor/Trophoblastic cells) and stained. Putative fetal cells were collected by single cell laser-assisted microdissection and identified as fetal or maternal cells by Short Tandem Repeat genotyping. NIPD was blindly performed on 6 mothers at risk of having a fetus with Cystic Fibrosis or Spinal Muscular Atrophy. RESULTS: Trophoblastic cells were recovered from all tested cervical samples with a frequency of 2-12 trophoblasts per 2 ml. NIPD was blindly obtained and verified in 6 mothers at risk of having a fetus with Cystic Fibrosis or Spinal Muscular Atrophy. DISCUSSION: Although larger confirmation studies are required, this is the first report providing a solid proof of principle that trophoblasts can be consistently and safely recovered from cervical samples. Since they are a source of pure fetal DNA, i.e. fetal DNA not mixed with maternal DNA, they constitute an ideal target to develop NIPD of recessive diseases, which is a technical challenge for methods based on cell free DNA.

Accumulation of lead in tissues after its administration in drinking water to laboratory rats.

Lead administered to laboratory rats in drinking water (0.1-0.8%) as lead acetate solution tends to accumulate in collagen-rich tissues such as tendons and the skin. The amount of lead deposited (and also zinc present in the tissue without its supplementation) correlates with the blood supply to the tissue investigated. The highest deposits of lead were observed in placenta and chorionic membranes, though here only about 60% are collagen-bound. No differences in the drinking habits of the animals were observed and also at lower concentrations of lead in the drinking water no dose dependence was revealed. However, at 0.8% of lead in drinking water considerable accumulation of lead was observed in all tissues investigated.

Influences of the environmental pollution on the immune system: some recent views.

The authors discuss the contemporary progress in preventive immunology with special attention to unfavourable effects of environmental pollution. They followed-up these problems systematically for more than twenty years and in this paper they present some of their results. They stress the importance of the protective effect of balanced nutrition with an adequate supply of vitamins and trace elements. The unfavourable effect of pollution is documented by different health aspects of the population living in the heavily polluted region of Northern Bohemia.

Relation between concentration of lead, zinc and lysozyme in placentas of women with intrauterine foetal growth retardation.

Intrauterine foetal growth retardation (IUGR) implies increased risk of morbidity and mortality of the newborn. Aetiology of intrauterine retardation is probably multifactorial and may include maternal infection, malnutrition, placental dysfunction, hypertension, toxaemia, smoking, professional and environmental exposure. The work concentrates on the lead, zinc and lysozyme levels in blood and placental tissues of 50 females in the IUGR group and 43 females from a control group. Statistically significant differences in zinc and lead levels between the compared group were found. The IUGR group had lower zinc and higher lead levels. A significant negative correlation of zinc and lead levels was observed. We found a statistically significant relationship between lead levels in placental tissues and the age of the pregnant women. Higher age is associated with higher lead levels in placental tissue, whereas zinc levels decrease. In placental tissues of pregnant females of the IUGR group higher lysozyme levels were found. On the basis of the discussed results the authors recommend zinc supplementation during the pregnancy.

[Relation of metal and lysozyme levels in the placentas of women with intrauterine fetal growth retardation]. / Vztah koncentrace kovu a lyzozymu v placentách zen s intrauterinní rustovou retardací plodu.

In a group of women who gave birth to a foetus with marked growth retardation and 27 women who were delivered of eutrophic neonates the lead, cadmium, zinc and lysozyme levels in placental tissue were assessed. The investigation revealed the following results: the lead level was in the investigated group significantly higher than in the control group (15.24 ng/g vs. 11.31 ng/g). Conversely the zinc levels were significantly higher in the control group (20.52 micrograms/g vs. 14.3 micrograms/g of placental tissue). The lead, cadmium and lysozyme values rise with the womens' age in the examined placentae, while the zinc levels decline. With the elevated zinc level the lead and cadmium content in the placentae of the exposed group declines. The lysozyme values increase along with the rise of all investigated elements with the exception of zinc, where the dynamics are reversed. The findings justify the recommendation of zinc supplementation during pregnancy.

[The role of immunology in monitoring the effects of environmental pollution]. / Prinos immunologie pro sledování vlivu kontaminace zivotního prostredí.

The paper gives a neat summary of experience acquired from two decades of immunological testing methods used for studying the effect of environmental contamination of the human organism. Immunological examination is part of a series of methods for a systematic follow-up of the state of health of the population. The paper underlines the complicated process leading to the resulting individual immune reactivity, which can be regarded as an outcome of multilateral interaction between the immune genetically conditioned potential and external environmental influences.