Biology subjects

Jensen, J. S.

Publications and source records attributed to Jensen, J. S..

3 recordsLinked to original sources

bioRxiv2024

The genital tract microbiota of IVF patients and oocyte donors: a comparative analysis

Recent studies have observed an association between genital tract microbiota and reproductive outcomes in patients undergoing in vitro fertilization (IVF). This finding could be caused by ascending dysbiosis from the vagina to the endometrium. The main objective of this study was to compare the microbiota and total bacterial load in the vagina, cervix and endometrium of IVF patients and oocyte donors. Thus, a total of two cohorts were explored: IVF patients (N=27) and healthy oocyte donors (N=26). The microbiota was investigated using 16S rRNA gene sequencing of the V3-V4 hypervariable regions, as well as qPCR for common vaginal species and total bacterial load. The study used a transcervical sampling approach for the endometrial microbiota samples. The highest bacterial load was seen in the vagina (median 2.6*109; 95% CI 9.7*108 - 7.1*109; 16S rRNA gene copies/swab), followed by the cervix (median 9.0*107; 95% CI 3.3*107 - 2.4*108; 16S rRNA gene copies/swab) and the endometrium (median 8.6*106; 95%CI 3.1*106 - 2.4*107; 16S rRNA gene copies/swab). Only 1% of the observed variation between genital tract samples was explained by patient group (IVF patient or oocyte donor) and less than 1% of the variation between genital tract samples was explained by the anatomical site. Although, findings could be impacted by the transcervical sampling approach, 16S rRNA gene sequencing as well as species-specific qPCR showed a similar microbiota composition present in the cervix and the endometrium when compared to the vaginal microbiota.

microbiology↗

bioRxiv2019

Characterization of the vaginal DNA virome in health and dysbiosis: an opening study in patients with non-female factor infertility

BackgroundBacterial vaginosis (BV) is characterised by a reduction in Lactobacillus spp. abundance and increased abundance of facultative anaerobes, like Gardnerella vaginalis. BV aetiology is not fully understood, but bacteriophages could play a pivotal role causing perturbation of the vaginal bacterial community. Here we investigate the vaginal viral community, including bacteriophages, and its association to the bacterial community and BV-status.\n\nMethodsVaginal samples from 48 patients undergoing IVF treatment for non-female factor infertility were subjected to metagenomic sequencing of purified virus-like particles. The vaginal viral community was characterized and correlated with BV-status, bacterial community structure and presence of key vaginal bacterial species.\n\nResultsThe majority of identified vaginal viruses belonged to the class of double-stranded DNA bacteriophages, with eukaryotic viruses constituting 4% of total reads. Clear links between viral community composition and BV (q = 0.006, R = 0.26) as well as presence of L. crispatus (q = 0.001, R = 0.43), L. iners, Gardnerella vaginalis and Atopobium vaginae were found (q < 0.002, R > 0.15). Interestingly, also the eukaryotic viral community was correlated with BV-status (q = 0.018, R = 0.20).\n\nConclusionsThe vaginal virome is clearly linked with bacterial community structure and BV-status.\n\nClinical Trials RegistrationNCT02042352.

microbiology↗

bioRxiv2018

De novo mutations drive the spread of macrolide resistant Mycoplasma genitalium: mathematical modelling study

BackgroundThe rapid spread of azithromycin resistance in sexually transmitted Mycoplasma genitalium infections is a growing concern. It is not yet clear to what degree macrolide resistance in M. genitalium results from the emergence of de novo mutations or the transmission of resistant strains.\n\nMethodsWe analyzed epidemiological data and developed a compartmental model to investigate the contribution of de novo macrolide resistance mutations to the spread of antimicrobial-resistant M. genitalium. We fitted the model to data from France, Denmark and Sweden and estimated treatment rates of infected individuals and the time point of azithromycin introduction.\n\nResultsWe found a high probability of de novo resistance (12%, 95% CI 8-17%), which is responsible for the observed rapid spread of antimicrobial resistant M. genitalium. The estimated per capita treatment rate in France was lower than in Denmark and Sweden but confidence intervals for the three estimates overlap. The estimated dates of introduction of azithromycin in each country are consistent with published reports.\n\nConclusionsSince de novo resistance is the main driver of macrolide resistance in M. genitalium, blind treatment of urethritis with azithromycin is not recommended. Clinical management strategies for M. genitalium should limit the unnecessary use of macrolides.

microbiology↗