P-591 Cellular heterogeneity in the preovulatory follicle correlates with response to stimulation with recombinant FSH and affects somatic cell gene expression levels

Study question

What is the difference in the composition and gene expression of pre-ovulatory follicular somatic cells between normo- and hyporesponder patients to rFSH stimulation?

Summary answer

Gene expression changes in the somatic cells of the preovulatory follicles of hyporesponder patients is partly attributable to distinct cell populations.

What is known already

Some women undergoing IVF respond suboptimally to the preceding ovarian stimulation without an indication of poor ovarian insufficiency nor advanced age. The gene expression levels in the somatic cells of their pre-ovulatory follicles have not been determined. However, the somatic cells play key roles in the transfer of gonadotrophin signals and in steroidogenesis. In the preovulatory follicle, being >20 mm in size, the somatic cells are exposed to various molecular gradients that drive their differentiation. Due to advancements in sequencing technologies the importance of somatic cell sub-populations in the etiologies of ovarian infertility can now be investigated by bioinformatic methods.

Study design, size, duration

Consecutive IVF patients <41 years of age were recruited at Nova Vita Clinic, Estonia, undergoing the antagonist stimulation protocol with rFSH administration. Ovarian puncture was performed for all patients after 36 hours of hCG stimulaton. rFSH dose >200 IU per one retrieved oocyte was considered as an indication for hyporesponse. Ten normo- and 9 hyporesponder patients were enrolled.

Participants/materials, setting, methods

Cells from the follicular fluid devoid of the cumulus oocyte complex were collected by centrifugation. RNA-seq was performed on the pooled cells of all participants. The study groups were compared by differential gene expression analysis by DESeq2. Single-cell RNA-seq was performed for >6000 individual cells of 3 normoresponder patients and cellular sub-populations were determined with Seurat package. CIBERTSORTx software was used to deconvolute the proportion of cell types from bulk RNA-seq data of all participants.

Main results and the role of chance

Alterations in the gene expression of ovarian somatic cells have been previously attributed to female age. We demonstrate that 407 genes are differentially expressed (FDR<0.05) between normo- and hyporesponder IVF patients after age adjustment. These genes were enriched into pathways of extracellular matrix reorganization (31 genes, FDR<0.005), post-translational protein phosphorylation (16 genes, FDR<0.006) and regulation of insulin-like growth factor transport and uptake by insulin-like growth factor binding proteins (16 genes, FDR<0.019).

In addition, the sequencing of > 24 000 individual cells from 3 normoresponder patients revealed the somatic cell types of the preovulatory follicle in high resolution indicating the presence of immune cell populations (N = 4), epithelial cells, theca, cumulus cells and mural granulosa cell sub-populations (N = 7). Bioinformatic cell type deconvolution demonstrated significant differences between proportions of distinct cell sub-populations between normo- and hyporesponder patients and that several differentially expressed genes between the study groups can be attributed to a specific mural granulosa sub-population.

Limitations, reasons for caution

The number of study participants is small due to the high cost of the study methods.

Wider implications of the findings

The study demonstrates that hyporesponse to stimulation is associated with age-unrelated disturbances in gene expression of preovulatory somatic cells and that different somatic cell populations may have important underlying functions in the ovarian etiologies of infertility.

Trial registration number

not applicable

Capture of Time-Loss Overuse Soccer Injuries in the National Collegiate Athletic Association's Injury Surveillance System, 2005-2006 Through 2007-2008

CONTEXT

  Overuse injuries are reported to account for nearly 50% of sports injuries and, due to their progressive nature and the uncertainty regarding date of onset, are difficult to define and categorize. Comparing the capture rates of overuse injuries between injury-surveillance systems and medical records can clarify completeness and determinants of how overuse injuries are represented in injury-surveillance data.

OBJECTIVE

  To estimate the capture rate of time-loss medical-attention overuse injuries in men's and women's soccer in the National Collegiate Athletic Association Injury Surveillance System (NCAA ISS) compared with medical records maintained by certified athletic trainers and assess the differences in completeness of capture and factors contributing to those differences.

DESIGN

  Capture-recapture study.

SETTING

  Fifteen NCAA institutions provided NCAA ISS and medical record data from men's and women's soccer programs from 2005-2006 through 2007-2008.

PATIENTS OR OTHER PARTICIPANTS

  National Collegiate Athletic Association men's and women's soccer players.

MAIN OUTCOME MEASURE(S)

  Time-loss medical-attention overuse injuries were defined as injuries with an overuse mechanism of injury in the NCAA ISS or medical records. Capture rates were calculated as the proportion of total overuse injuries classified as having overuse mechanisms in the NCAA ISS and the NCAA ISS and medical records combined.

RESULTS

  The NCAA ISS captured 63.7% of the total estimated overuse mechanisms of injury in men's and women's soccer players. The estimated proportion of overuse injury mechanisms captured by both the NCAA ISS and medical records was 37.1%. The NCAA ISS captured more overuse injury mechanisms in men's soccer than in women's soccer (79.2% versus 45.0%, χ² = 9.60; P = .002) athletes.

CONCLUSIONS

  From 2005-2006 through 2007-2008, the NCAA ISS captured only two thirds of time-loss medical-attention overuse mechanisms of injury in men's and women's soccer players. Future researchers should consider supplementing injury-surveillance data with a clinical record review to capture the burden of these injuries.

Multicopy integration of mini-Tn7 transposons into selected chromosomal sites of a Salmonella vaccine strain

Chromosomal integration of expression modules for transgenes is an important aspect for the development of novel Salmonella vectors. Mini-Tn7 transposons have been used for the insertion of one such module into the chromosomal site attTn7, present only once in most Gram-negative bacteria. However, integration of multiple mini-Tn7 copies might be suitable for expression of appropriate amounts of antigen or combination of different modules. Here we demonstrate that integration of a 9.6 kb mini-Tn7 harbouring the luciferase luxCDABE (lux) occurs at the natural attTn7 site and simultaneously other locations of the Salmonella chromosome, which were engineered using λ-Red recombinase to contain one or two additional artificial attTn7 sites (a-attTn7). Multicopy integration even at closely spaced attTn7 sites was unexpected in light of the previously reported distance-dependent Tn7 target immunity. Integration of multiple copies of a mini-Tn7 containing a gfp cassette resulted in increasing green fluorescence of bacteria. Stable consecutive integration of two mini-Tn7 encoding lacZ and lux was achieved by initial transposition of lacZ-mini-Tn7, subsequent chromosomal insertion of a-attTn7 and a second round of transposition with lux-mini-Tn7. Mini-Tn7 thus constitutes a versatile method for multicopy integration of expression cassettes into the chromosome of Salmonella and possibly other bacteria.

High cytokine levels in perforated acute otitis media exudates containing live bacteria

Acute otitis media (AOM) is an inflammatory response to microbes in the middle ear, sometimes associated with rupture of the tympanic membrane. Human leukocytes produce different patterns of inflammatory mediators in vitro when stimulated with Gram-positive and Gram-negative bacteria, respectively. Here, we investigated the cytokine and prostaglandin E2 (PGE2) responses in middle ear fluids (MEFs) from children with spontaneously perforated AOM, and related the mediator levels to the presence of pathogens detected by culture (live) or PCR (live or dead). Furthermore, the in vivo cytokine pattern was compared with that induced in leukocytes stimulated by dead bacteria in vitro. MEFs with culturable pathogenic bacteria contained more interleukin (IL)-1β (median: 110 μg/L vs. <7.5 μg/L), tumour necrosis factor (TNF) (6.3 μg/L vs. <2.5 μg/L), IL-8 (410 μg/L vs. 38 μg/L) and IL-10 (0.48 μg/L vs. <0.30 μg/L) than culture-negative fluids, irrespective of PCR findings. IL-6 and PGE2 were equally abundant (69-110 μg/L) in effusions with live, dead or undetectable bacteria. Cytokine levels were unrelated to bacterial species and to the presence or absence of virus. Similar levels of TNF and IL-6 as found in the MEFs were obtained by in vitro stimulation of leukocytes, whereas 11 times more IL-1β and 3.5 times more IL-8 were produced in vivo, and 22 times more IL-10 was produced in vitro. Vigorous production of proinflammatory cytokines accompanies AOM with membrane rupture, regardless of the causative agent, but the production seems to cease rapidly once the bacteria are killed and fragmented. IL-6 and PGE2, however, remain after bacterial disintegration, and may play a role in the resolution phase.

High cytokine levels in perforated acute otitis media exudates containing live bacteria

Acute otitis media (AOM) is an inflammatory response to microbes in the middle ear, sometimes associated with rupture of the tympanic membrane. Human leukocytes produce different patterns of inflammatory mediators in vitro when stimulated with Gram-positive and Gram-negative bacteria, respectively. Here, we investigated the cytokine and prostaglandin E2 (PGE2) responses in middle ear fluids (MEFs) from children with spontaneously perforated AOM, and related the mediator levels to the presence of pathogens detected by culture (live) or PCR (live or dead). Furthermore, the in vivo cytokine pattern was compared with that induced in leukocytes stimulated by dead bacteria in vitro. MEFs with culturable pathogenic bacteria contained more interleukin (IL)-1β (median: 110 μg/L vs. <7.5 μg/L), tumour necrosis factor (TNF) (6.3 μg/L vs. <2.5 μg/L), IL-8 (410 μg/L vs. 38 μg/L) and IL-10 (0.48 μg/L vs. <0.30 μg/L) than culture-negative fluids, irrespective of PCR findings. IL-6 and PGE2 were equally abundant (69-110 μg/L) in effusions with live, dead or undetectable bacteria. Cytokine levels were unrelated to bacterial species and to the presence or absence of virus. Similar levels of TNF and IL-6 as found in the MEFs were obtained by in vitro stimulation of leukocytes, whereas 11 times more IL-1β and 3.5 times more IL-8 were produced in vivo, and 22 times more IL-10 was produced in vitro. Vigorous production of proinflammatory cytokines accompanies AOM with membrane rupture, regardless of the causative agent, but the production seems to cease rapidly once the bacteria are killed and fragmented. IL-6 and PGE2, however, remain after bacterial disintegration, and may play a role in the resolution phase.

Failure to detect the presence of prions in the uterine and gestational tissues from a Gravida with Creutzfeldt-Jakob disease

The vertical transmission of a prion disease from infected mothers to their offspring is believed to be one of the routes for the natural spread of animal prion diseases. Supporting this notion is the observation that prion infectivity occurs in the placenta of infected ewes. Furthermore, the prion protein (PrP), both in its cellular form (PrP(C)) and its pathological isoform (PrP(Sc)), has been observed at the fetal-maternal interface of scrapie-infected sheep. However, whether these features of prion infectivity also hold true for human prion diseases is currently unknown. To begin to address such an important question, we examined PrP in the uterus as well as gestational tissues, including the placenta and amniotic fluid, in a pregnant woman with sporadic Creutzfeldt-Jakob disease (CJD). Although the proteinase K (PK)-resistant prion protein, PrP27-30, was present in the brain tissues of the mother, the PrP detected in the uterus, placenta, and amniotic fluid was sensitive to PK digestion. Unlike PrP(C) in the brain and adjacent cerebrospinal fluid, the predominant PrP species in the reproductive and gestational tissues were N-terminally truncated, similar to urine PrP. Our study did not detect abnormal PrP in the reproductive and gestational tissues in this case of CJD. Nevertheless, examination by a highly sensitive bioassay is ongoing to ascertain possible prion infectivity from CJD in the amniotic fluid.

Spray bacteriotherapy decreases middle ear fluid in children with secretory otitis media

OBJECTIVE

Secretory otitis media (SOM) is characterised by persistent fluid in the middle ear cavity, but the cause is unknown. We investigated the clinical, bacteriological and immunological effects of treatment with probiotic bacteria on SOM.

DESIGN

In this double-blind pilot/preliminary study, 60 children with long-standing SOM (median 6 months) who were scheduled for insertion of tympanostomy tubes were randomised to nasal spray treatment with Streptococcus sanguinis, Lactobacillus rhamnosus or placebo for 10 days before surgery. Clinical evaluation was carried out after 10 days of treatment. Middle ear fluid (MEF) was collected during surgery for quantification of cytokines and detection of bacteria by culture and polymerase chain reaction (PCR). Nasopharyngeal swabs were obtained before treatment and at surgery.

RESULTS

Complete or significant clinical recovery occurred in 7/19 patients treated with S sanguinis compared to 1/17 patients in the placebo group (p<0.05). In the L rhamnosus treatment group, 3/18 patients were cured or much better (p = 0.60 compared with placebo). Spray treatment did not alter the composition of the nasopharyngeal flora or the cytokine pattern observed in the nasopharynx or MEF, except for a higher level of IL-8 found in the nasopharynx of L rhamnosus treated children.

CONCLUSIONS

This study shows that spray treatment with S sanguinis may be effective against SOM. The mechanism for the effect remains to be investigated.