Detection of novel autoantigens in patients with recurrent miscarriage: description of an approach and preliminary findings

Aim To develop and test a protocol for isolation of potential auto-antigens from chorionic tissue that may be linked to recurrent miscarriage (RM). Methods The strategy included: 1) isolation of IgGs tightly bound to chorionic tissue of RM patients by protein G chromatography; 2) construction of affinity columns using the chorionic antibodies for isolation of auto-antigens; 3) enrichment of auto-antigens from detergent extracted solution of chorionic proteins by affinity chromatography; 4) separation by dodecyl sulfate-electrophoresis followed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry identification. Results Five potential auto-antigens were detected: neutral alpha-glucosidase AB, endoplasmin, transitional endoplasmic reticulum ATPase, putative endoplasmin-like protein, and cytoplasmic actin 2. Conclusions We developed a strategy for identification of auto-antigens in the chorionic tissue of women with RM, which could be of diagnostic and prognostic value

SPECTRUM AND FREQUENCY OF NK CELL RECEPTOR GENES AMONG CYSTIC FIBROSIS PATIENTS

Aim – to establish and analyze the spectrum of KIR genes in people with a confirmed diagnosis of Cystic fibrosis (CF), homozygote of F508del mutation of the СFTR gene for understanding the genetic predisposition of congenital immunity key part functioning during CF. Materials and Methods. Examined 48 people with a confirmed diagnosis of CF, homozygotes of the F508del mutation of the CFTR gene, and 104 practically healthy people without the F508del mutation of the CFTR gene from the control group. The following molecular genetic methods were used: DNA extraction from peripheral blood cells, KIR genotyping by PCR-SSP for the presence or absence of the 14 KIR genes (KIR2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DL1, 3DL2, 3DL3, 3DS1). Results – molecular genetic studies of KIR-genes repertoire in the group of cystic fibrosis patients showed a decrease in the frequency of genes, responsible for activating NK cells receptors. Of the five examined NK cell activation genes, one gene was completely absent, namely 2DS4, and another (2DS1) was detected in only 3 of 48 patients examined, which was 6.25 %, and this figure is significantly lower in comparison with the control group (c2=4.801, p<0.05). Regarding the genes of NK-cell inhibitory receptors, all investigated genes were detected in the study group (8 in general). By detection frequency, they mostly correspond to the control group, with the exception of the 2DL3 gene, found in patients with CF with a significantly lower frequency (c2=11.97, p<0.005). Conclusion – for the first time in the group of patients with CF, a study was performed on the frequency and spectrum of KIR-genes, responsible for NK cell receptors. Reducing the frequency of activation NK cell receptor genes in patients with CF can lead to a weakening of congenital immunity and the severity of infectious processes during C

Cytogenetic and molecular analyses of de novo translocation dic(9;13)(p11.2;p12) in an infertile male

BACKGROUND: Whole arm t(9;13)(p11;p12) translocations are rare and have been described only a few times; all of the previously reported cases were familial. RESULTS: We present here an infertile male carrier with a whole-arm reciprocal translocation dic(9;13)(p11.2;p12) revealed by GTG-, C-, and NOR-banding karyotypes with no mature sperm cells in his ejaculate. FISH and genome-wide 400 K CGH microarray (Agilent) analyses demonstrated a balanced chromosome complement and further characterised the abnormality as a dicentric chromosome (9;13): dic(9;13)(pter→p11.2::p12→qter),neo(9)(pter→p12→neo→p11.2). An analysis of the patient’s ejaculated cells identified immature germ cells at different phases of spermatogenesis but no mature spermatozoa. Most (82.5%) of the germ cells were recognised as spermatocytes at stage I, and the cell nuclei were most frequently found in pachytene I (41.8%). We have also undertaken FISH analysis and documented an increased rate of aneuploidy of chromosomes 15, 18, X and Y in the peripheral blood leukocytes of our patient. To study the aneuploidy risk in leukocytes, we have additionally included 9 patients with non-obstructive azoospermia with normal karyotypes. CONCLUSIONS: We propose that the azoospermia observed in the patient with the dic(9;13)(p11.2;p12) translocation was most likely a consequence of a very high proportion (90%) of association between XY bivalents and quadrivalent formations in prophase I

Can telomere shortening be the main indicator of non-viable fetus elimination?

Abstract Background Telomeres are transcriptionally inactive genomic areas, which, if shortened, are associated with pathological processes, unsuccessful fertilization, aging, and death. Telomere dysfunction has also been linked to chromosomal rearrangements and genomic instability. The role of telomeres in postnatal life has been extensively studied and discussed both in physiological as well as in pathological processes. However, the role of telomere length in prenatal development is still poorly understood, and mainly concerns the preimplantation stage. The aim of this study was to estimate relative telomere length in spontaneously eliminated human embryos between 5th and 12th week of gestation. Results Relative telomere length was measured from total genomic DNA using a real-time polymerase chain reaction approach. In this study, we examined relative telomere length in 80 spontaneously eliminated embryos and in 25 embryos eliminated due to induced abortions. Relative telomere length in spontaneous abortions was significantly lower (P = 0.000001) compared to the induced abortions. Spontaneous abortions with aneuploid anomalies (monosomy X, trisomy 21, trisomy 16 and triploidy) were characterized by shorter telomeres, compared to spontaneous abortions, subgroup with euploid (46,XN) karyotype. Conclusion Spontaneously lost pregnancies are characterized by shortened telomeres, especially in embryos with aneuploidies. We hypothesize that the shortening of telomeres is involved in the processes leading to spontaneous abortions

Loss of Imprinting of Gene in the Chorionic Tissues of Spontaneously Eliminated Human Embryos

Insulin-like growth factor-2 (IGF-2) is a mitogen, growth and differentiation modulator for many cell types. It is mainly expressed during the prenatal development, and its activity strongly depends on the genomic imprinting. Genomic imprinting in the chorionic tissues of spontaneously eliminated human embryos has been studied on the model of 820-AG (Apa1) of the IGF-2 gene locus. Molecular and genetic analysis was performed on the polymorphic 820-AG IGF2 locus in 107 samples of DNA extracted from the chorionic tissues of spontaneously eliminated human embryos within 5–10 weeks of gestation. Presence of AG genotype Apa 1 single nucleotide polymorphisms of the IGF-2 was shown to cause more than a 7-fold increase in the risk of embryo elimination. Thus, the loss of genomic imprinting of the IGF-2 gene may be an important cause of the miscarriages in human

Global methylation status of sperm DNA in carriers of chromosome structural aberrations

Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatozoa of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine (m 5 C) levels in spermatozoa and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure (n = 24), and the controls comprised normozoospermic sperm volunteers (n = 23). The global m 5 C level was measured using thin-layer chromatography (TLC) and immunofluorescence (IF) techniques. The sperm chromatin integrity was assessed using aniline blue (AB) staining and TUNEL assay. The mean m 5 C levels were similar between the investigated chromosome structural aberrations carriers (P) and controls (K). However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls (P < 0.05). Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the m 5 C level juxtaposed in both analyzed groups (P vs K) was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations

Familial Infertility (Azoospermia and Cryptozoospermia) in Two Brothers—Carriers of t(1;7) Complex Chromosomal Rearrangement (CCR): Molecular Cytogenetic Analysis

Structural aberrations involving more than two breakpoints on two or more chromosomes are known as complex chromosomal rearrangements (CCRs). They can reduce fertility through gametogenesis arrest developed due to disrupted chromosomal pairing in the pachytene stage. We present a familial case of two infertile brothers (with azoospermia and cryptozoospermia) and their mother, carriers of an exceptional type of CCR involving chromosomes 1 and 7 and three breakpoints. The aim was to identify whether meiotic disruption was caused by CCR and/or genomic mutations. Additionally, we performed a literature survey for male CCR carriers with reproductive failures. The characterization of the CCR chromosomes and potential genomic aberrations was performed using: G-banding using trypsin and Giemsa staining (GTG banding), fluorescent in situ hybridization (FISH) (including multicolor FISH (mFISH) and bacterial artificial chromosome (BAC)-FISH), and genome-wide array comparative genomic hybridization (aCGH). The CCR description was established as: der(1)(1qter-&gt;1q42.3::1p21-&gt;1q42.3::7p14.3-&gt;7pter), der(7)(1pter-&gt;1p2 1::7p14.3-&gt;7qter). aCGH revealed three rare genes variants: ASMT, GARNL3, and SESTD1, which were ruled out due to unlikely biological functions. The aCGH analysis of three breakpoint CCR regions did not reveal copy number variations (CNVs) with biologically plausible genes. Synaptonemal complex evaluation (brother-1; spermatocytes II/oligobiopsy; the silver staining technique) showed incomplete conjugation of the chromosomes. Associations between CCR and the sex chromosomes (by FISH) were not found. A meiotic segregation pattern (brother-2; ejaculated spermatozoa; FISH) revealed 29.21% genetically normal/balanced spermatozoa. The aCGH analysis could not detect smaller intergenic CNVs of few kb or smaller (indels of single exons or few nucleotides). Since chromosomal aberrations frequently do not affect the phenotype of the carrier, in contrast to the negative influence on spermatogenesis, there is an obvious need for genomic sequencing to investigate the point mutations that may be responsible for the differences between the azoospermic and cryptozoospermic phenotypes observed in a family. Progeny from the same parents provide a unique opportunity to discover a novel genomic background of male infertility