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Skeletal muscle tissue engineering constitutes an emerging therapeutic repair strategy aiming for structural and functional restoration following traumatic injury, deep burns, congenital malformation or surgical tumor removal. As for similar musculoskeletal acute and degenerative affections, allogenic progenitor cell therapy represents a promising clinical approach to synergistically supplement traditional surgical care. Preliminary studies have established the adequation of primary human fetal muscle progenitors (hFMPs) for applications in regenerative medicine. Such therapeutic cell sources combined with bioresorbable scaffolds optimally integrate in murine muscle injury models without causing immune rejection. The present work aimed at functional recovery assessment following standardized application of hFMPs in an optimized murine skeletal muscle wound model. Cryopreserved hFMPs were initiated and culture-expanded before seeding in equine collagen scaffolds. Gastrocnemius muscles of C57BL/6 mice were injured following a standardized protocol.

Study question How could multicolor flow cytometry (MFC) help to identify ovarian subpopulations that could be used for ovarian reconstruction with isolated follicles? Summary answer MFC is useful to identify ovarian cell subpopulations in the ovarian cortex. What is known already Ovarian tissue cryopreservation is a fertility preservation option for women before gonadotoxic chemo- and/or radiotherapy. However, graft of cryopreserved ovarian tissue must be performed with caution in women suffering from malignancies that may metastasize to the ovaries. For this purpose, functional ovarian tissue qualification is essential to identify ovarian cell subpopulations that could be used for ovary reconstruction in combination with isolated follicles. Furthermore, ischemic tissue damage occurring after the graft is currently another important issue to be resolved for successful ovarian reuse. Study design, size, duration We developed an automated ovarian tissue dissociation method to obtain ovarian cell suspensions. Then, we used MFC for the identification of different cell subpopulations in the cell suspension thus obtained. Participants/materials, setting, methods Human ovarian tissues from patients undergoing surgery for polycystic ovary syndrome were used in this study. Biopsies of ovarian cortex (fresh or frozen-thawed) were dissociated using an automated dissociation method. We used FVS780 and SYTO13 markers to gate viable ovarian cells by MFC. Variable markers were chosen to differentiate and identify cell subpopulations among the viable ovarian cells. Main results and the role of chance The dissociation yield was on average 1.59 ± 1.58 x 106 and 0.78 ± 0.72 x 106 viable ovarian cells per 100 mg of fresh (n = 17) and frozen-thawed (n = 43) ovarian cortical tissue, respectively. On average, 35.4 ± 13.1% of viable ovarian cells were CD34 + (n = 61, stromal phenotype). Concerning endothelial phenotype, 7.8 ± 5.5% of CD31+ cells (n = 51) and 5.3 ± 3.6% of CD144+ cells (n = 29) were identified among viable ovarian cells. Vimentin marker is found in 25.6 ± 10.8% of viable ovarian cells (n = 23) and CD326 (EpCAM expression) in 0.6 ± 0.8% (n = 16). Finally, pericyte phenotype (CD34-/Vimentin-/CD31-/CD146+/ CD140b+) was identified in 4.6 ± 4.3% of viable ovarian cells (n = 7). Limitations, reasons for caution We do not know how these ovarian cell subpopulations could be a factor associated or not with time for ovarian function recovery in vivo after ovarian tissue graft and the impact of these ovarian cells on the ovarian microenvironment of an artificial ovary. Wider implications of the findings: Functional qualification of ovarian tissue can be performed by MFC. MFC is a promising tool for ovarian cortex qualification before reuse of cryopreserved ovarian tissue. Cell sorting could be used to separate and isolate cell subpopulations and add these cells with isolated follicles in an ovarian reconstruction program. Trial registration number Not applicable

Background Cryopreservation of ovarian tissue is a fertility-preservation option for women before gonadotoxic treatments. However, cryopreserved ovarian tissue transplantation must be performed with caution in women with malignancies that may metastasize to the ovaries. For this purpose, detecting minimal residual disease (MRD) in the ovarian cortex using sensitive methods is a crucial step. We developed an automated ovarian tissue dissociation method to obtain ovarian cell suspensions. Results We assessed MRD by multicolor flow cytometry (MFC) in cryopreserved ovarian cortex of 15 leukemia patients: 6 with B-cell acute lymphoblastic leukemia (B-ALL), 2 with T-cell acute lymphoblastic leukemia (T-ALL) and 7 with acute myeloid leukemia (AML). Ovarian MRD was positive in 5 of the 15 leukemia patients (one T-ALL and 4 AML). No B-ALL patient was positive by MFC. Quantitative reverse-transcribed polymerase chain reaction was performed when a molecular marker was available, and confirmed the MFC results for 3 patients tested. Xenografts into immunodeficient mice were also performed with ovarian cortical tissue from 10 leukemia patients, with no evidence of leukemic cells after the 6-month grafting period. Conclusions In conclusion, this is the first study using MFC to detect MRD in ovarian cortical tissue from acute leukemia patients. MFC has been accepted in clinical practice for its ease of use, the large number of parameters available simultaneously, and high throughput analysis. We demonstrate here that MFC is a reliable method to detect MRD in cryopreserved ovarian tissue, with a view to controlling the oncological risk before ovarian tissue transplantation in leukemia patients.

This article presents a novel low cost force sensing platform for the mechanical characterisation of human oocytes. This platform is compatible with the specific context of Assisted Reproductive Technology (ART). The oocyte is placed inside a standard Petri dish filled with a culture medium. It is immobilized using a holding pipette. The disposable parts used to mechanically test each oocyte are made of glass. This configuration is very similar to the one used in IntraCytoplasmic Sperm Injection protocol excepted that the injection pipette is replaced by a glass indenter. This platform uses two passive and linear magnetic springs to measure the nanoforce applied to the oocyte. The stabilisation of the unstable magnetic springs is passively achieved using the reaction force generated by the compressed oocyte. Some preliminary results obtained with an experimental platform are presented. The global magnetic stiffness of the indenter, evaluated by simulation and experimentally identified, is about 0.0013 N m−1.

This study aimed to develop a method to detect ovarian residual disease by multicolor flow cytometry in acute leukemia patients.We designed an experimental model consisting in adding acute leukemia cells to a cell suspension obtained from healthy ovarian cortex. Leukemic cell detection within the ovarian cell suspension required the development of a specific myeloid antibody panel different from that commonly used for minimal residual disease (MRD) monitoring in bone marrow. The method was then used to detect ovarian residual disease in 11 acute leukemia patients.Multicolor flow cytometry is able to evaluate the presence of viable leukemic cells in the ovarian cortex with good specificity and robust sensitivity of 10-4. We observed a good correlation between multicolor flow cytometry and quantitative polymerase chain reaction results. Ovarian residual disease detection by multicolor flow cytometry was positive in 3 out of 11 acute leukemia patients.Multicolor flow cytometry can potentially be applied to ovarian tissue from all acute leukemia patients and is essential to evaluate the risk of cancer re-seeding before autograft of ovarian tissue in case of acute leukemia.

Background Ovarian tissue cryopreservation (OTC) is the only option available to preserve fertility in prepubertal females with neuroblastoma (NB), a childhood solid tumor that can spread to the ovaries, with a risk of reintroducing malignant cells after an ovarian graft. Procedure We set out to determine whether the analysis of TH (tyrosine hydroxylase), PHOX2B (paired-like homeobox 2b), and DCX (doublecortin) transcripts using quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) could be used to detect NB contamination in ovarian tissue. Analyses were performed on benign ovarian tissue from 20 healthy women between November 2014 and September 2015 at the University Hospital of Clermont-Ferrand. Pericystic benign ovarian tissues were collected and contaminated with increasing numbers of human NB cells (cell lines IMR-32 and SK-N-SH) before detection using RT-qPCR. Results TH and DCX transcripts were detected in uncontaminated ovarian tissue from all the donors, hampering the detection of small numbers of tumor cells. By contrast, PHOX2B was not detected in any uncontaminated ovarian fragment. PHOX2B levels were significantly increased from 10 NB cells. Our study is the first to evaluate minimal residual disease detection using NB mRNAs in human ovarian tissue. Only PHOX2B was a reliable marker of NB cells contaminating ovarian tissue. Conclusions These results are encouraging and offer hope in the near future for grafting ovarian tissue in women who survive cancer, whose fertility has been jeopardized by treatment, and who could benefit from OTC without oncological risk.

Ovarian tissue cryopreservation can be proposed to patients before gonadotoxic treatments to preserve fertility in case of malignant pathologies like leukemia. Autograft of ovarian tissue is the only available method to restore fertility, but it presents a risk of re-implanting malignant cells. This study aimed to develop a method to detect minimal residual disease in ovarian tissue by multicolor flow cytometry in acute myeloid leukemia. We designed an experimental model consisting in adding acute myeloid leukemia cells to a cell suspension obtained from healthy reference ovarian tissue. Leukemic cell detection within the ovarian cell suspension required the development of a specific myeloid antibody panel different from that commonly used for MRD monitoring in bone marrow. The method was then used to detect minimal residual disease in cryopreserved ovarian tissue from 4 acute myeloid leukemia patients. Multicolor flow cytometry is able to evaluate the presence of viable leukemic cells in the ovarian cortex with good specificity and robust sensitivity of 10-4. We observed a good correlation between multicolor flow cytometry and quantitative polymerase chain reaction results. Ovarian minimal residual disease detection by multicolor flow cytometry was positive in 2 out of 4 acute myeloid leukemia patients. Multicolor flow cytometry can potentially be applied to ovarian tissue from all acute myeloid leukemia patients and is essential to evaluate the risk of cancer re-seeding before autograft of ovarian tissue in case of acute myeloid leukemia.

STUDY QUESTION How can leukemic cells be detected in cryopreserved ovarian tissue? SUMMARY ANSWER Multicolor flow cytometry (FCM) is useful to evaluate the presence of viable leukemic cells in the ovarian cortex with a high specificity and a robust sensitivity. WHAT IS KNOWN ALREADY Storing ovarian tissue is an option to preserve fertility before gonadotoxic radiotherapy or chemotherapy treatments. However, transplantation of cryopreserved ovarian cortex to women cured of leukemia is currently not possible due to the risk of cancer re-seeding. STUDY DESIGN, SIZE, DURATION We developed an automated ovarian cortex dissociation technique and we used eight-color FCM to identify leukemic cells with a series of dilutions added to ovarian single cell suspensions obtained from healthy cortex. PARTICIPANTS/MATERIALS, SETTINGS, METHODS Healthy ovarian cortex originated from women between 23 and 39 years of age undergoing laparoscopic ovarian drilling for polycystic ovary syndrome. Blood or bone marrow cells were collected in acute lymphoblastic leukemia (ALL) patients at diagnosis. MAIN RESULTS AND THE ROLE OF CHANCE The tissue dissociation technique yield was 1.83 ± 1.49 × 10(6) viable nucleated cells per 100 mg of ovarian cortex. No cell exhibiting a leukemic phenotype was present in the normal ovarian cortex. Added leukemic cells were detected using their leukemia-associated phenotype up to a dilution of 10(-4). When specific gene rearrangements were present, they were detected by real-time quantitative PCR at the same dilution. The ovarian cortex from two leukemia patients was then used, respectively, as positive and negative controls. LIMITATIONS, REASONS FOR CAUTION Making available minimal residual disease (MRD) detection techniques (multicolor FCM, PCR and xenograft), that can be used either alone or together, is essential to add a fail-safe oncological dimension to pre-autograft monitoring. WIDER IMPLICATIONS OF THE FINDINGS This approach can be performed on fresh ovarian tissue during cryopreservation or on frozen/thawed tissue before reimplantation and it is currently the only available technique in cases of ALL where no molecular markers are identified. This new perspective should lead to studies on ovarian tissue from leukemia patients, for whom the presence of MRD should be established before autograft. STUDY FUNDINGS/COMPETING INTEREST(S) The study was supported by the BioMedicine Agency, the Committee of the League against Cancer, the Besancon University Hospital, DGOS/INSERM/INCa and the regional Council of Franche-Comte. There were no conflicts of interest to declare.

International audience; We present a simple optical micro-system used to measure the transmission spectra of oocytes in order to qualify their maturation stage. Two applications of the device are possible: (i) the evaluation of the maturation stages of oocytes, and (ii) the development of a fertilization indicator. For the first application, CV, MI and MII oocytes were also analysed. Transmission spectra allow the 3 maturation stages to be identified but cannot be used to estimate the maturity of an unknown oocyte. Oocytes are subject to continuous development. This is why spectral separation of the 3 maturation stages cannot be made although they can be visually identified. However, the visual observation remains biologist-dependent. We therefore investigated the temporal maturation evolution of the oocytes in terms of transmission spectra and probability analysis. Results show that oocytes to be fertilized should not only be chosen in the MII stage, but also at the right time during the MII stage. This particular aspect requires further investigation. However, spectral measurements could be used as a technique for monitoring the maturation evolution of the oocytes. Fertilized oocytes exhibiting fertilization abnormalities were also tested. The device proved to be an efficient fertilization indicator.

Objective To report a child with Beckwith-Wiedemann syndrome (BWS) born after assisted reproductive technology (ART) to an HIV serodiscordant couple. Design Case report. Setting Academic medical center. Patient(s) A child with BWS born after ART to an HIV serodiscordant couple. Intervention(s) Assisted reproductive techniques. Main Outcome Measure(s) ART and HIV. Result(s) Since 2003, it has been suggested that there is an association between ART and BWS, which is a congenital overgrowth syndrome characterized by macrosomia, macroglossia, visceromegaly, umbilical and abdominal wall abnormalities, and an increased risk of developing embryonal tumors in childhood. It is a multigenic disorder resulting from genetic or epigenetic alterations of genes on chromosome 11p15. Methylation errors account for 50%–60% of sporadic cases and almost 100% of cases born after ART. We report the birth of a child diagnosed with BWS arising from an ART cycle to an HIV serodiscordant couple with no history of infertility. This case cannot constitute conclusive evidence but it raises various questions. Conclusion(s) Assisted reproductive technology seems to be in the causal pathway but a male/female factor or an iatrogenic factor is also possible.

International audience; In human, neuronal migration disorders are commonly associated with developmental delay, mental retardation, and epilepsy. We describe here a new mouse mutant that develops a heterotopic cortex (HeCo) lying in the dorsolateral hemispheric region, between the homotopic cortex (HoCo) and subcortical white matter. Cross-breeding demonstrated an autosomal recessive transmission. Birthdating studies and immunochemistry for layer-specific markers revealed that HeCo formation was due to a transit problem in the intermediate zone affecting both radially and tangentially migrating neurons. The scaffold of radial glial fibers, as well as the expression of doublecortin is not altered in the mutant. Neurons within the HeCo are generated at a late embryonic age (E18) and the superficial layers of the HoCo have a correspondingly lower cell density and layer thickness. Parvalbumin immunohistochemistry showed the presence of gamma-aminobutyric acidergic cells in the HeCo and the mutant mice have a lowered threshold for the induction of epileptic seizures. The mutant showed a developmental delay but, in contrast, memory function was relatively spared. Therefore, this unique mouse model resembles subcortical band heterotopia observed in human. This model represents a new and rare tool to better understand cortical development and to investigate future therapeutic strategies for refractory epilepsy.

cpQSOx1 is a member of the QSOx family of proteins, expressed in the guinea pig (Cavia porcellus) and ortholog of the rat rQSOx1. In this study, in vitro experiments were conducted and showed that, as other member of this family, cpQSOx1 has a sulfydryl oxidase activity, and is a secreted protein. Then, the expression of this enzyme was researched in the guinea pig brain, as very little information exists yet on the expression of QSOx family members in the central nervous system. By immunohistochemistry, RT-PCR and in situ hybridization, cpQSOx1 is synthesized by neurons throughout the whole guinea pig central nervous system. Reticular structures as the basal forebrain, reticular thalamic nucleus and reticular nuclei of the brainstem contained the densest labeling. These results are discussed in terms of putative roles of this protein in synaptic strengthening and in redox activities.

Objet La reutilisation du tissu ovarien cryoconserve se fait actuellement par technique d’autogreffe dans le cadre d’un protocole de recherche clinique. L’inconvenient majeur de la greffe est le risque de reintroduction de cellules cancereuses via le greffon dans certaines pathologies neoplasiques a haut risque, c’est pourquoi nous travaillons au developpement d’une alternative a l’autogreffe. Materiel et methode Un protocole multicentrique intitule PERIDATOR-DATOR, pilote par le CHRU de Besancon, vise a constituer une cohorte de patientes candidates a la reutilisation de leur tissu ovarien et a permettre la realisation d’autogreffes de cortex ovarien. Parallelement, nous avons mis au point une technique de dissociation enzymatique du tissu ovarien par une collagenase de norme GMP. Les follicules sont pipetes manuellement et leur viabilite est verifiee (calceine AM/ethidium homodimere-1 ; bleu Trypan). Nous avons effectue une modelisation consistant en l’ajout de cellules leucemiques a la suspension de cellules ovariennes saines ; puis isole les follicules. Apres rincage, nous avons recherche par cytometrie en flux multicouleurs (CMF) si des cellules leucemiques etaient presentes. Resultats Quatre-vingt-quatorze patientes sont incluses dans la cohorte PERIDATOR ; 15 greffes ont ete realisees. Par ailleurs, la technique de dissociation du tissu ovarien a permis d’isoler 1361 follicules (moyenne = 210 ± 205 pour 100 mg ; n = 13) avec un taux de survie moyen des follicules de 93,4 %. Apres 3 lavages, l’analyse par CFM de 24 solutions contenant les follicules ovariens isoles et dans lesquelles differentes concentrations de cellules leucemiques ont ete ajoutees, a permis de detecter une moyenne de 3 evenements ([min = 0 ; max = 22], n = 8). Conclusion Les premiers resultats des greffes sont satisfaisants, 6 naissances ayant deja ete obtenues. Les travaux preliminaires d’isolement de follicules ovariens permettent d’envisager la possibilite d’effectuer des essais cliniques ulterieurs et de proceder a des reconstructions ovariennes a l’aide de follicules isoles depourvus de cellules malignes.

International audience; OBJECTIVE: To report the first case of restoration of ovarian activity and live birth after cryopreserved ovarian tissue autograft in a patient without cancer treated by allogeneic bone marrow transplantation. DESIGN: Case report. SETTING: University hospital. PATIENT(S): One woman with homozygous sickle cell anemia. INTERVENTION(S): An orthotopic autotransplantation of ovarian cortical strips was performed after freeze-thawing. MAIN OUTCOME MEASURE(S): Cryopreservation of ovarian tissue, bone marrow transplantation, ovarian autograft, and restoration of ovarian function. RESULT(S): In autumn 2005, biopsy samples of ovarian tissue were cryopreserved before chemotherapy followed by bone marrow transplantation. In spring 2008, because the patient had been menopausal for 2.5 years as a result of the conditioning therapy, an orthotopic autotransplantation of thawed ovarian cortex was performed. The patient conceived spontaneously in a natural cycle in autumn 2008, and delivered a healthy female child in June 2009. CONCLUSION(S): Cryopreservation of ovarian tissue with subsequent autotransplantation is an emerging procedure for preserving the fertility of young patients with a high risk of premature ovarian failure (POF) resulting from gonadotoxic treatment. This case opens up new perspectives in cases of nonmalignant diseases.

International audience; During intracytoplasmic sperm injection (ICSI) attempts, oocytes reaching metaphase II are microinjected. A morphological examination under a microscope is the usual method for determining oocyte maturity. The level of oocyte maturity is based on the meiotic status (Germinal Vesicle, metaphase I and metaphase II) of the oocytes with respect to their increasing maturity. In this letter, we summarize the studies conducted to analyze cytoplasm maturity using various microsystems and image processing. Optical microsystems are used to measure the transmission spectra and refractive index of the oocytes. We compared the transmission spectra measurements to the transmission electron microscopy results. Karhunen-Loeve transform is also used to evaluate the maturity of the oocytes. To summarize, optical analysis techniques are a minimally invasive technology allowing cytoplasm maturity to be assessed. Oocytes should not only be qualified in terms of GV, MI or MII, but also regarding their temporal evolution over the course of these maturation stages. The ultimate aim of this work is to describe the maturation of the oocytes by a trajectory in a multidimensional space and to determine when would be the best time for successful fertilization.

Abstract 4482 One major drawback of myeloablative allogeneic stem cell transplantation is the near 100% risk of profound fertility impairment leading to early menopause and sterility in most female patients. This toxic effect is especially critical in patients without malignant disease, i.e hemoglobinopathies or other inherited diseases. Cryopreservation of ovarian tissue with subsequent autotransplantation is an emerging procedure to preserve the fertility of young patients with a high risk of premature ovarian failure resulting from radiotherapy or chemotherapy for cancer. We report the restoration of ovarian activity and pregnancy with live birth after an orthotopic transplantation of frozen/thawed ovarian tissue in a 23 year old female patient given a transplant for sickle cell disease. In spring 2005, the patient of S/S hemoglobin genotype experienced a central nervous system stroke with unilateral central retinal artery occlusion. Monthly exchange transfusions were started from then and a pretransplant procedure was undertaken with a 10/10 matched sibling male donor who was heterozygous for HbS. In autumn 2005, biopsy samples of ovarian tissue were cryopreserved prior to conditioning. The patient received a conditioning regimen with IV busulfan (12.8 mg/kg total dose), cyclophosphamide (200 mg/kg total dose) and antilymphocyte globulin (15 mg/kg total dose) followed by allogeneic bone marrow transplantation (BMT). A stable 100% donor chimerism was obtained from D60.The patient developed grade II acute GVHD treated by steroids, then followed by limited chronic GVHD treated by a combination of mycophenolate-mofetil and ciclosporin. The treatment was tapered and stopped 7 months after BMT. After BMT, the patient presented clinical menopause with amenorrhoea and hot flushes due to premature ovarian failure. FSH and LH concentrations rose to menopausal levels. Hormone replacement therapy with oestro-progestogens was started 6 months after BMT and was maintained until ovarian function restoration after ovarian transplantation. In spring 2008, as the patient had been menopausal for 2.5 years as a result of the conditioning chemotherapy, an orthotopic autotransplantation of ovarian cortex was performed. The cortical fragments were grafted according to the following procedure: a first laparoscopy was performed to create a peritoneal windows between the right iliac vessels and an ovarian window in the remaining left ovary with the aim of further inducing angiogenesis. One thawed strip of ovarian cortex was cut in fragments, that were fixed in the ovarian incision and deposited in the peritoneal window. Three days later, a second laparoscopy was performed and three thawed cortical strips were fixed into the left ovary and one into the peritoneal window. Ovarian function recovery was evaluated by hormonal levels and follicular development was observed by ultrasound. The patient conceived spontaneously in a natural cycle in autumn 2008, and delivered a healthy female child in June 2009. This first case report of pregnancy and delivery after ovarian autograft in a patient treated by allogeneic BMT suggests that cryopreservation of ovarian tissue should be offered prior to SCT not only to women of childbearing age but also to prepubertal patients, as primordial follicles are already present in the post natal ovaries. This technique still deserves further investigations in leukemias but appears safe in non malignant diseases. Time line of treatment Disclosures: No relevant conflicts of interest to declare.

The cryopreservation of ovarian cortex is the only technique available for prepubertal girls and women when their pathology requires the administration of a highly gonadotoxic treatment whose initiation cannot be delayed. Autotransplantation has so far been the only available method to re-use cryopreserved ovarian tissue, and has resulted in more than 130 births worldwide, including three at the Besançon Hospital. However, in cases of neoplastic disease with a risk of ovarian metastatic localization, this technique may present a risk of reintroducing malignant cells likely to be present in the graft. Alternative methods to cryopreserved ovarian tissue autograft based on the use of isolated ovarian follicles are currently under development. The aim of this thesis was to develop a protocol allowing the isolation and the qualification of ovarian follicles that can be used in cell therapy for human purposes. In a first step, a validation of the technique to isolate ovarian follicles was carried out from the dissociation of cortical ovarian fragments, taken from patients undergoing a laparoscopic ovarian drilling, using collagenase NB6 which is produced according to good manufacturing practices. Follicles thus obtained were analyzed in terms of viability (before and after in vitro culture), yield, morphology and proliferative state. In a second step, the carcinologic safety of follicular suspensions obtained after isolation was evaluated by multicolor flow cytometry using a model involving the contamination of follicular suspensions with leukemic cells from patients suffering from acute myeloid leukemia (AML) or acute lymphoblastic leukemia (LAL) with known immunophenotype. Collagenase NB6 has allowed the isolation of a large number of viable follicles, mostly at the primordial stage and the majority of which were unactivated even after three days of in vitro culture in a fibrin matrice. Our isolation technique followed by three washes has allowed the elimination of leukemic cells previously added to follicular suspensions, in 23 out of 24 cases, without damaging isolated follicles. Multicolor flow cytometry is an effective analytical technique for assessing leukemic cell contamination of suspensions containing isolated ovarian follicles. The protocol to isolate human ovarian follicles, performed with the clinical grade collagenase NB6, may be considered for an ovarian reconstruction to human therapeutic purposes.; La cryoconservation de cortex ovarien est la seule technique envisageable pour les patientes pré-pubères et les femmes dont la pathologie nécessite l’administration d’un traitement hautement gonadotoxique dont l’initiation ne peut être différée. L’autotransplantation est jusqu’à présent la seule méthode disponible de réutilisation du tissu ovarien cryoconservé, et a permis d’obtenir plus de 130 naissances dans le monde, dont trois au CHRU de Besançon. Toutefois, en cas de pathologie néoplasique à risque de localisation métastatique ovarienne, cette technique peut présenter un risque de réintroduction de cellules malignes susceptibles d’être présentes dans le greffon. Des méthodes alternatives à l’autogreffe de tissu ovarien cryopréservé fondées sur l’utilisation de follicules ovariens isolés sont actuellement en développement. L’objectif de cette thèse a été de développer un protocole permettant l’isolement et la qualification de follicules ovariens qui pourront être utilisés en thérapie cellulaire à usage humain. Dans un premier temps, une validation de la technique d’isolement de follicules ovariens a été réalisée à partir de la dissociation de fragments de cortex ovarien, issus de patientes ayant subit une résection percœlioscopique, à l’aide d’une collagénase NB6 produite selon les bonnes pratiques de fabrication. Les follicules ainsi obtenus ont été analysés en termes de viabilité (immédiate et après culture in vitro), rendement, morphologie et état prolifératif. Dans un deuxième temps, la sécurité carcinologique des suspensions folliculaires obtenues après isolement a été évaluée par cytométrie en flux multicouleurs à l’aide d’une modélisation ayant consisté en la contamination de suspensions folliculaires avec des cellules leucémiques issues de patients souffrant de leucémies aigües myéloïdes (LAM) ou lymphoblastiques (LAL) d’immunophénotype connu. La collagénase NB6 a permis l’isolement d’un grand nombre de follicules vivants, principalement au stade primordial, et dont la majorité était non activée, même après trois jours de culture in vitro dans un gel de fibrine. La technique d’isolement suivie de trois lavages a permis d’éliminer les cellules leucémiques préalablement ajoutées aux suspensions folliculaires dans 23 cas sur 24, sans endommager les follicules isolés. La cytométrie en flux multicouleurs est une technique d’analyse efficace pour évaluer la contamination, par des cellules leucémiques, de suspensions contenant des follicules ovariens isolés. Le protocole d’isolement de follicules ovariens humains, ayant été réalisé avec la collagénase NB6 de grade clinique, peut être envisagé pour une reconstruction ovarienne à visée thérapeutique humaine.

The cryopreservation of ovarian cortex is the only technique available for prepubertal girls and women when their pathology requires the administration of a highly gonadotoxic treatment whose initiation cannot be delayed. Autotransplantation has so far been the only available method to re-use cryopreserved ovarian tissue, and has resulted in more than 130 births worldwide, including three at the Besançon Hospital. However, in cases of neoplastic disease with a risk of ovarian metastatic localization, this technique may present a risk of reintroducing malignant cells likely to be present in the graft. Alternative methods to cryopreserved ovarian tissue autograft based on the use of isolated ovarian follicles are currently under development. The aim of this thesis was to develop a protocol allowing the isolation and the qualification of ovarian follicles that can be used in cell therapy for human purposes. In a first step, a validation of the technique to isolate ovarian follicles was carried out from the dissociation of cortical ovarian fragments, taken from patients undergoing a laparoscopic ovarian drilling, using collagenase NB6 which is produced according to good manufacturing practices. Follicles thus obtained were analyzed in terms of viability (before and after in vitro culture), yield, morphology and proliferative state. In a second step, the carcinologic safety of follicular suspensions obtained after isolation was evaluated by multicolor flow cytometry using a model involving the contamination of follicular suspensions with leukemic cells from patients suffering from acute myeloid leukemia (AML) or acute lymphoblastic leukemia (LAL) with known immunophenotype. Collagenase NB6 has allowed the isolation of a large number of viable follicles, mostly at the primordial stage and the majority of which were unactivated even after three days of in vitro culture in a fibrin matrice. Our isolation technique followed by three washes has allowed the elimination of leukemic cells previously added to follicular suspensions, in 23 out of 24 cases, without damaging isolated follicles. Multicolor flow cytometry is an effective analytical technique for assessing leukemic cell contamination of suspensions containing isolated ovarian follicles. The protocol to isolate human ovarian follicles, performed with the clinical grade collagenase NB6, may be considered for an ovarian reconstruction to human therapeutic purposes.; La cryoconservation de cortex ovarien est la seule technique envisageable pour les patientes pré-pubères et les femmes dont la pathologie nécessite l’administration d’un traitement hautement gonadotoxique dont l’initiation ne peut être différée. L’autotransplantation est jusqu’à présent la seule méthode disponible de réutilisation du tissu ovarien cryoconservé, et a permis d’obtenir plus de 130 naissances dans le monde, dont trois au CHRU de Besançon. Toutefois, en cas de pathologie néoplasique à risque de localisation métastatique ovarienne, cette technique peut présenter un risque de réintroduction de cellules malignes susceptibles d’être présentes dans le greffon. Des méthodes alternatives à l’autogreffe de tissu ovarien cryopréservé fondées sur l’utilisation de follicules ovariens isolés sont actuellement en développement. L’objectif de cette thèse a été de développer un protocole permettant l’isolement et la qualification de follicules ovariens qui pourront être utilisés en thérapie cellulaire à usage humain. Dans un premier temps, une validation de la technique d’isolement de follicules ovariens a été réalisée à partir de la dissociation de fragments de cortex ovarien, issus de patientes ayant subit une résection percœlioscopique, à l’aide d’une collagénase NB6 produite selon les bonnes pratiques de fabrication. Les follicules ainsi obtenus ont été analysés en termes de viabilité (immédiate et après culture in vitro), rendement, morphologie et état prolifératif. Dans un deuxième temps, la sécurité carcinologique des suspensions folliculaires obtenues après isolement a été évaluée par cytométrie en flux multicouleurs à l’aide d’une modélisation ayant consisté en la contamination de suspensions folliculaires avec des cellules leucémiques issues de patients souffrant de leucémies aigües myéloïdes (LAM) ou lymphoblastiques (LAL) d’immunophénotype connu. La collagénase NB6 a permis l’isolement d’un grand nombre de follicules vivants, principalement au stade primordial, et dont la majorité était non activée, même après trois jours de culture in vitro dans un gel de fibrine. La technique d’isolement suivie de trois lavages a permis d’éliminer les cellules leucémiques préalablement ajoutées aux suspensions folliculaires dans 23 cas sur 24, sans endommager les follicules isolés. La cytométrie en flux multicouleurs est une technique d’analyse efficace pour évaluer la contamination, par des cellules leucémiques, de suspensions contenant des follicules ovariens isolés. Le protocole d’isolement de follicules ovariens humains, ayant été réalisé avec la collagénase NB6 de grade clinique, peut être envisagé pour une reconstruction ovarienne à visée thérapeutique humaine.