O-128 Intra-cycle alterations of the uterine microbiota in patients with recurrent miscarriage or recurrent implantation failure and healthy controls

Study question

Uterine microbiota: are there differences within three major time points of the menstrual cycle in healthy controls, recurrent miscarriage (RM) and recurrent implantation failure (RIF) patients?

Summary answer

Compared to controls, RM and RIF patients showed an altered uterine microbiota throughout the menstrual cycle, with a lower dominance of lactobacilli.

What is known already

In contrast to the former notion of a sterile womb, bacterial colonization in the uterus and the placenta has been demonstrated. Studies showed that Lactobacillus-dominated endometrial microbiota correlate with reproductive success. Moreover, the presence of non-Lactobacillus-dominated microbiota, especially with detection of Gardnerella and Streptococcus in the endometrial fluid, seems to be associated with lower implantation-, ongoing pregnancy- and live birth-rates. However, intra-cycle variations in healthy women as well as possible alterations in patients with RM or RIF remain unknown.

Study design, size, duration

In total, n = 20 RM patients (≥ 3 consecutive miscarriages), n = 20 RIF patients (≥3 fresh or frozen embryo transfers with negative serum hCG, good quality embryos) and n = 10 healthy controls (no pregnancy) were included in this study. All patients had a 28 day menstrual cycle. During follicular, ovulatory and luteal-phase, after a thorough cleaning of the cervix, a flexible catheter was introduced into the uterine cavity and a uterine flushing with 1ml of NaCl was performed.

Participants/materials, setting, methods

Bacterial DNA was extracted using a QIAamp DNA kit (Qiagen) in combination with a PrecellysR24 homogenizer (Peqlab, Erlangen, Germany) according to the manufacturer’s instructions. The V3-V4 region of the bacterial 16S rRNA gene was amplified. Samples were pooled in equimolar ratios and progressed to pyrosequencing using an Illumina MiSeq se-quencer with MiSeq Kit V2 (250 bp paired-end). Analysis of 16S rRNA data, including alpha- and beta-diversity, were calculated using the phyloseq package in R.

Main results and the role of chance

For the Shannon index (species richness and evenness) a significant decrease during the ovulation period was shown in the control group, indicating a more uniform microbiota (p < 0.05). This loss of diversity was not shown in RIF and RM patients. Overall, we could observe a higher similarity in taxonomic distribution in RM compared to the RIF patients. Longitudinal dynamics included increases in Firmicutes (CTRL and RM only) and a concomitant loss of Proteobacteria. Notably, significant amounts of bacteroides were only detected in the RIF patients. Actinobacteria were more frequent in both, RM and RIF as compared to controls.

Limitations, reasons for caution

To minimize the impact of a potential contamination, we performed pre-experiments with paired samples both from the vaginal fornix and the endometrial cavum and could show a significant difference in overall microbiome configuration. However, the route of sample can still be prone to contamination.

Wider implications of the findings

For the first time, we were able to show cycle-dependent alterations in the endometrial microbiome. These findings underline the role of an altered endometrial microbiome as a cause for RM and RIF and can contribute to the future establishment of therapeutic strategies in cases of a dysbalanced microbiome.

Trial registration number

Drks00020803

P–647 How do migraine attacks change during puberty?

Study question

How do the stage of puberty and the menstrual cycle influence characteristics of migraine?

Summary answer

During puberty, the frequency of migraine attacks increases, especially during the follicular phase. The pattern of migraine changes to a typical adult pattern of migraine.

What is known already

Up to puberty, headaches are as common in girls as in boys. After the onset of puberty migraine is more prevalent in adolescent girls suggesting an association with sex hormones. Attacks of menstrual migraine are characterized by a longer duration, tend to be more severe, and are less responsive to acute medication compared to migraine attacks which are independent from the menstrual cycle phase.

Study design, size, duration

For this prospective cohort study 47 girls were recruited from two Departments of Pediatrics and Adolescent Medicine between 01/2016 and 12/2018.

Participants/materials, setting, methods

Girls between 7 and 18 years old, diagnosed with migraine without aura according to the “International Classification of Headache Disorders II” diagnostic criteria, took part. Three groups (pre-, peri-, and postpubertal) were formed according to the Tanner stage and the onset of a regular menstruation. Girls kept a daily headache and menstrual cycle diary over 8 weeks. Ovulatory cycles were analyzed by weekly progesterone saliva tests.

Main results and the role of chance

Three groups according to Tanner stage and onset of regular menstruation were compared: pre- (n = 16), peri- (n = 19) and post-pubertal (n = 12) girls. A significant difference in migraine frequency was found between pre- and post- pubertal girls (p = 0.005). Headache characteristics did not differ significantly between the three groups. Interestingly, a higher frequency of attacks in follicular phase occurred compared to luteal phase (p = 0.030).

Limitations, reasons for caution

Repeated blood sampling would have been a more reliable technique compared to saliva assays. The sample size is small.

Wider implications of the findings: During puberty, the number of migraine attacks but not the specific headache characteristics changes in adolescent girls which should be taken into consideration regarding the management of these patients.

Trial registration number

AN2013–0027

Influence of temperature on the inheritance of adult life span in Drosophila melanogaster

Mating experiments were performed at 27 degrees C, 22 degrees C, and 17 degrees C, to investigate the inheritance of adult life span of highly inbred strains of Drosophila melanogaster. Effects of temperature difference were quantitatively analyzed at the genotypic level. In the temperature range of 17-27 degrees C the autosomal longevity alleles, A1 and A2, exerted major effects. Their effects produced longer life spans as the temperature decreased. The sex-linked longevity alleles, X1 and X2, played a secondary role in influencing life span, and they displayed different effects at different temperatures. Each genotype showed correspondence to the life span expected from the combinations of these longevity genes at the respective temperatures. The genetic loci controlling life span in these inbred strains were named JmA and JmX from "Ju-myo" which means life span or longevity in Japanese.

A difference in the proteins found in young adults of inbred strains of Drosophila melanogaster which correlates with genetically-determined, long or short life span

One-dimensional electrophoresis was performed on extracts of flies collected from across all ages. Protein gel patterns were compared for two strains of Drosophila melanogaster with distinctly long and short adult life spans that result from different alleles of longevity genes. An inter-strain difference was observed in the changes in protein pattern in the 77 kDa region in period of day 0-5 after emerging. We propose that the protein involved is a product of autosomal longevity alleles A1 and A2 at the Jm A locus and is related to development of longevity potentials in the preimaginal stage.

Purification and characterization of a protein associated with genetically-determined longevity difference in Drosophila melanogaster

Earlier studies have shown a correlation between the presence of a 77 kDa protein in the proteins extracted from young adult Drosophila melanogaster (D.m.) and the autosomal longevity allele. A2 at the JmA locus. In this study, a 77 kDa protein has been isolated from pupae of D.m. of a long-lived strain of genotype A2A2, and was purified by DEAE chromatography, ConA column chromatography, and two cycles of gel filtration. The purified protein has a molecular weight of 76,600 (by SDS-PAGE), an isoelectric point of pH 6.5, and molar extinction coefficient A(280(1%) = 18.3. It is a glycoprotein containing 3.3% hexose. Supplementing the food of D.m. with the purified protein at 5 x 10(-4) micrograms/ml, beginning at day 5 after emergence, resulted in an increase in the survival rate and maximal life span of both short-lived and long-lived strains of D.m.

Her-2/neu and urokinase-type plasminogen activator and its inhibitor in breast cancer

PURPOSE

Recent studies suggest that HER-2/neu specifically promotes the invasive capacity of tumor cells by up-regulating secretion of the proteolytic enzyme, urokinase-type plasminogen activator (uPA), or its inhibitor, plasminogen activator inhibitor-1 (PAI-1), in colon and gastric cancer. It was the purpose of this study to: (a) evaluate the association between HER-2/neu and uPA and PAI-1 expression in a large primary breast cancer cohort; (b) perform the first multivariate analysis, including HER-2/neu, uPA, and PAI-1 in breast cancer; and (c) define the effect of HER-2/neu overexpression on uPA and PAI-1 expression in breast cancer cells.

EXPERIMENTAL DESIGN

HER-2/neu, uPA, and PAI-1 were measured as continuous variables by ELISA in primary breast cancer tissue extracts from 587 patients with clinical follow-up and analyzed for correlations with clinical outcome. Furthermore, a full-length human HER-2/neu cDNA was introduced into five human breast cancer cell lines to define the effects of HER-2/neu overexpression on uPA and PAI-1 expression. In addition, we tested whether HER-2/neu antibodies could reverse any given alteration of uPA and PAI-1 levels.

RESULTS

Our findings indicate a weak positive association between HER-2/neu and uPA (r = 0.147; P < 0.001) and no association between HER-2/neu and PAI-1 (r = 0.07; P = 0.085). HER-2/neu overexpression (> or =400 fmol/mg) and high levels of uPA/PAI-1 (> or =5.5 ng/mg and/or > or =14 ng/mg, respectively) were significantly associated with shorter disease-free survival (DFS; P < 0.001 and P = 0.003) and metastasis-free survival (MFS; P = 0.015 and P < 0.001). Multivariate analysis revealed prognostic independence between HER-2/neu and the uPA/PAI-1 axis for DFS and MFS. Both uPA and PAI-1 had no significant discriminatory effect among HER-2/neu-positive patients for DFS. The prognostic value of HER-2/neu overexpression for MFS, however, was significantly enhanced by elevated uPA expression (P = 0.053). Stable transfection of the HER-2/neu gene into multiple human breast cancer cell lines resulted in consistent down-regulation of uPA or PAI-1 expression. In addition, anti-HER-2/neu antibodies did not significantly affect uPA or PAI-1 expression in human cancer cell lines naturally overexpressing HER-2/neu.

CONCLUSIONS

The present findings suggest that the invasive phenotype elicited by HER-2/neu overexpression in breast cancer is not a direct effect of uPA or PAI-1 expression. HER-2/neu and the uPA/PAI-1 axis have been shown to affect the invasive capacity of breast cancer independently. Determination of uPA can provide significant additional prognostic information for MFS in HER-2/neu-positive and -negative patients.

Restricted polymorphism of the mannose-binding lectin gene of indigenous Australians

Mannose-binding lectin (MBL) is an important complement-activating protein of the human innate immune system. Deficiency of MBL is associated with an increased risk of various infections and arises from three structural gene mutations in exon 1 (variants B, C and D) and/or the presence of a low efficiency promoter. The C allele is found in sub-Saharan Africa whereas the B allele is found elsewhere, suggesting that these mutations occurred after the suggested hominid migration out of Africa [100-150 000 years before present (BP)]. Paradoxically, these alleles may have a selective advantage in protection against intracellular pathogens and occur at particularly high frequencies in sub-Saharan Africa (C variant) and South America (B variant). Since hominids reached Australia at least 50 000 years ago, a study of MBL polymorphisms in the indigenous population was of interest. Using heteroduplex technology we found a paucity of MBL structural gene mutations in two population groups from geographically distinct regions. Of 293 individuals tested, 289 were wild-type and four were heterozygous for either the B or D allele. In each individual with an MBL mutation the HLA haplotype profile suggested some Caucasian admixture. We also found a restricted range of MBL promoter haplotypes and the serum MBL levels were higher than those of any other ethnic group studied to date (median 3.07 microg/ml). Our data suggest that the B mutation probably arose between 50 000 and 20 000 BP. Its absence from the founder gene pool of indigenous Australians may also partly explain their vulnerability to intracellular infections such as tuberculosis.

Sequence polymorphism in the mtDNA HV1 region in Japanese and Chinese

We investigated the nucleotide substitution and insertion/deletion polymorphism of the HV1 region in mtDNA by sequencing blood samples from 150 unrelated Japanese and 120 unrelated Chinese and revealed 108 sequence types from the Japanese group and 87 sequence types from the Chinese. Some substitutions were characteristic of East Asian populations as compared with data reported on Caucasian populations, and some were area-specific among East Asians. The level of genetic diversity and genetic identity revealed by this system was superior to that obtained by VNTR systems for nuclear DNA. These results show the usefulness of mtDNA sequencing in forensic examination for individual identification. We also found some sequence variations in the homopolymeric tract of cytosine (np16180-16194 in the Anderson's reference sequence) that might suggest some hints regarding the mechanisms for and the development of heteroplasmic length variations in this tract.

Overexpression of human testis antigens in Escherichia coli host cells is influenced by site of expression and the induction temperature

A panel of twenty human testis cDNA clones were expressed in an Escherichia coli expression system and six clones were found to express identifiable fusion polypeptides. Expression was found to be influenced not only by the site of localization of the polypeptide in the host cells, but also by the temperature used for induction. This emphasized the need for cytoplasmic and periplasmic expression of new antigens of unknown properties, as well as the use of temperatures of 30 degrees C or lower. A majority of the expressed polypeptides were mainly in an insoluble form. By reducing the induction temperature to 30 degrees C production of the soluble fraction was further improved.

Mitochondrial control-region sequence variation in aboriginal Australians

The mitochondrial D-loop hypervariable segment 1 (mt HVS1) between nucleotides 15997 and 16377 has been examined in aboriginal Australian people from the Darling River region of New South Wales (riverine) and from Yuendumu in central Australia (desert). Forty-seven unique HVS1 types were identified, varying at 49 nucleotide positions. Pairwise analysis by calculation of BEPPI (between population proportion index) reveals statistically significant structure in the populations, although some identical HVS1 types are seen in the two contrasting regions. mt HVS1 types may reflect more-ancient distributions than do linguistic diversity and other culturally distinguishing attributes. Comparison with sequences from five published global studies reveals that these Australians demonstrate greatest divergence from some Africans, least from Papua New Guinea highlanders, and only slightly more from some Pacific groups (Indonesian, Asian, Samoan, and coastal Papua New Guinea), although the HVS1 types vary at different nucleotide sites. Construction of a median network, displaying three main groups, suggests that several hypervariable nucleotide sites within the HVS1 are likely to have undergone mutation independently, making phylogenetic comparison with global samples by conventional methods difficult. Specific nucleotide-site variants are major separators in median networks constructed from Australian HVS1 types alone and for one global selection. The distribution of these, requiring extended study, suggests that they may be signatures of different groups of prehistoric colonizers into Australia, for which the time of colonization remains elusive.

Platelet antigen allele frequencies in Australian aboriginal and Caucasian populations

We have applied genotyping methods of PCR-SSOP and PCR-RFLP to three, bi-allelic platelet specific antigen systems HPA-1 (Pla), HPA-3 (Bak) and HPA-5 (Br). This combination of techniques offers flexibility for high volume or rapid typing. The phenotype and genotype frequencies of alleles from the three systems differ significantly between the Yuendumu Australian Aboriginals (Wailbri) and Australian Caucasians. The major differences are the very low frequencies of HPA-1b and HPA-3b in Yuendumu Aboriginals which are potentially relevant to platelet transfusion in patients of Australian Aboriginal descent.

Three newly identified A*24 alleles: A*2406, A*2413 and A*2414

Three previously unknown A24-related alleles were identified by PCR-SSO typing and confirmed by DNA sequencing in Australian Aboriginal populations (A*2406, 2413) and in individuals of South American descent (A*2414). A*2406 and A*2413 both have two adjacent (but different) nucleotide substitutions in codon 156 in exon 3 compared to A*2402, resulting in a single amino acid replacement in each allele. The South American A*2414 is apparently a hybrid between A2 and A24 with a segment of the A*24 sequence between codons 95 and 107 in exon 3 replaced with the A*02 sequence. Interallelic sequence exchange is the most likely mechanism in the generation of all three novel alleles. Compared to A*2402, the four amino acid substitutions in the A*2414 molecule would be expected to significantly change the shape of the peptide binding cleft, leading to selection of different peptide ligands. The single amino acid replacements in position 156 of the two Australian Aboriginal A*24 alleles may also have significant functional effects. In particular, Trp replacing Gln in position 156 (A*2406) is predicted to markedly reduce the volume of the peptide binding cleft, influence the interaction of HLA pockets with peptide side chains, and therefore, cause major changes in peptide presentation. These newly defined alleles may reflect the adaptive process of HLA genes to local environments.

Mitochondrial D-loop diversity in Australian riverine and Australian desert Aborigines

Population structure has been revealed in mitochondrial D-loop segment 1 (mt DLS1) sequences from Australian Aboriginal people in the Darling River region of NSW (Riverine) and from Yuendumu in central Australia (Desert). Comparison with five published global studies reveals that these Australians demonstrate greatest divergence from some Africans, least from Papua New Guinea (PNG) highlanders, and only slightly more divergence from some Pacific groups (Indonesian, Asian, Samoan, and coastal PNG). A median networks approach demonstrates that several hypervariable nucleotide sites within the DLS1 are likely to have undergone mutation independently. A comprehensive evaluation of specific nucleotide variants with the large amount of global sequence data now available has been achieved in three stages of analysis: (i) identification of key nucleotide variants (from the Cambridge reference sequence) in the Aboriginal Australian by pairwise comparison and construction of a 'local' median network, (ii) identification of key nucleotide variants in a selected global sample including Australian mtDLS1 types most different from each other, and (iii) calculation of the frequency with which these key nucleotide sites occur as variants in a greatly extended global sample. The third stage of the analysis revealed that nucleotides 16287 and 16356 are unique markers for representatives from the northern Riverine region. A 'thymine' at nucleotide 16223 is an informative signature of African and several identifiable non-African DLS1 types, whereas the 'cytosine' form is a marker for European, Pacific, and some Asian populations.

An ancient common origin of aboriginal Australians and New Guinea highlanders is supported by alpha-globin haplotype analysis

The origins of aboriginal Australians and their relationship with New Guineans and neighboring Southeast Asians remains controversial. We have studied the alpha-globin haplotype composition of an aboriginal tribe from central Australia, to address some of the ambiguities of previous studies. Australians have a haplotype repertoire that is shared with New Guinea highlanders, a fact that strongly supports a common origin of these two populations. Further, Australians and New Guinea highlanders have a different set of alpha haplotypes from Southeast Asians and a lower genetic diversity. This, coupled with the presence of many locally specific central Australian haplotypes, suggests that much of the original diversity was lost in a population bottleneck prior to or during the early colonization of Sahul and that subsequent recovery of diversity has been accompanied by the generation of new haplotypes. These conclusions contrast with some previous genetic studies suggesting links between Australians, coastal New Guineans, and present-day Southeast Asians. Much of this discrepancy appears to be due to more recent Southeast Asian admixture on the north coast of Australia.