The Isolation and Manufacture of GMP-Grade Bone Marrow Stromal Cells from Bone Specimens.

Bone marrow stromal cells (BMSCs, also known as bone marrow mesenchymal stem cells) are a plastic-adherent heterogeneous cell population that contain inherent skeletal progenitors and a subset of multipotential skeletal stem cells (SSCs). Application of BMSCs in therapeutic protocols implies its isolation and expansion under good manufacturing practices (GMP). Here we describe the procedures we have found to successfully generate practical BMSCs numbers, with preserved biological potency.

Scalable Manufacturing of Human Hematopoietic Stem/Progenitor Cells Exploiting a Co-culture Platform with Mesenchymal Stromal Cells.

In the context of hematopoietic cell transplantation, hematopoietic stem/progenitor cells (HSPC) from the umbilical cord blood (UCB) present several advantages compared to adult sources including higher proliferative capacity, abundant availability and ease of collection, non-risk and painless harvesting procedure, and lower risk of graft-versus-host disease. However, the therapeutic utility of UCB HSPC has been limited to pediatric patients due to the low cell frequency per unit of UCB. The development of efficient and cost-effective strategies to generate large numbers of functional UCB HSPC ex vivo would boost all current and future medical uses of these cells. Herein, we describe a scalable serum-free co-culture system for the expansion of UCB-derived CD34+-enriched cells using microcarrier-immobilized human bone marrow-derived mesenchymal stromal cells as feeder cells.

Optimization and Comparison of Three-Dimensional Culture Conditions in Different Media of Coculture and Encapsulation System for In Vitro Follicular Development in Bubalus bubalis.

The establishment of an in vitro culture system for complete oocyte maturation from the early stages of ovarian follicles is still a challenge. The aim of the present study was to assess the effect of different matrix with different culture media on the developmental growth of ovarian follicles in vitro. An ovarian histoarchitectural study was carried out to identify the primordial (0.027-0.039 mm), primary (0.041-0.079 mm), small preantral (0.085-0.131 mm), large preantral (0.132-0.294 mm), small antral (0.387-0.589 mm), and large antral (1.188-1.366 mm) follicles. Thus, large preantral follicles (0.2-0.3 mm) were mechanically isolated and cultured subsequently in different microconditions such as Dulbecco's modified Eagle's medium, Tissue Culture Medium-199 (TCM-199) and Opti-minimum essential medium, with same supplements where control (without matrix) was compared with matrix (coculture and encapsulation), which includes (1) buffalo fetal fibroblast cells, (2) cumulus cells, (3) ovarian mesenchymal cells, (4) collagen, (5) gelatin, and (6) Matrigel, cultured for 7 days in CO2 incubator at 38.5°C (5% CO2 in air). Cultured follicles were evaluated for growth rate (107.88% ± 10.24%), maturation rate (51.06% ± 6.53%), survivability rate (56.52% ± 3.42%), and antioxidant (catalase; CAT [1.58 ± 0.04 U/mg], superoxide dismutase; SOD [4.63 ± 0.05 U/mg], lactate dehydrogenase; LDH [1.48 ± 0.01 U/mg]) enzymatic activities, which showed significantly (p < 0.05) positive results in growth model with media TCM-199 than other studied groups. Furthermore, the development of large preantral follicles augmented significantly (p < 0.05) for growth rate (248.54% ± 9.51%), maturation rate (75.81% ± 7.07%), survivability rate (81.82% ± 3.02%), antioxidant (CAT [2.05 ± 0.03 U/mg], SOD [3.13 ± 0.12 U/mg], LDH [2.55 ± 0.51 U/mg]), and estradiol (175.83 ± 5.92 pg/mL) activities when they were encapsulated in Matrigel with nutritional requirements fulfilled by media TCM-199. These results provide better insight for the optimization of culture conditions for in vitro follicular development in the water buffalo, which will eventually assist in resolving the limitation of obtaining fewer competent oocytes for the embryo production in the species.

Extracellular vesicles derived from endometrial human mesenchymal stem cells enhance embryo yield and quality in an aged murine model†.

Advanced age is a risk factor undermining women's fertility. Hence, the optimization of assisted reproduction techniques is an interdisciplinary challenge that requires the improvement of in vitro culture systems. Here, we hypothesize that supplementation of embryo culture medium with extracellular vesicles from endometrial-derived mesenchymal stem cells (EV-endMSCs) may have a positive impact on the embryo competence of aged oocytes. In this work, 24 weeks old B6D2 female mice were used as egg donors and in vitro fertilization assays were performed using males from the same strain (8-12 weeks); the presumptive zygotes were incubated in the presence of 0, 10, 20, 40, or 80 µg/ml of EV-endMSCs. The results from the proteomic analysis of EV-endMSCs and the classification by Reactome pathways allowed us to identify proteins closely related with the fertilization process. Moreover, in our aged murine model, the supplementation of the embryo culture medium with EV-endMSCs improved the developmental competence of the embryos as well as the total blastomere count. Finally, gene expression analysis of murine blastocysts showed significant changes on core genes related to cellular response to oxidative stress, metabolism, placentation, and trophectoderm/inner cell mass formation. In summary, we demonstrate that EV-endMSCs increase the quality of the embryos, and according to proteomic and genomic analysis, presumably by modulating the expression of antioxidant enzymes and promoting pluripotent activity. Therefore, EV-endMSCs could be a valuable tool in human assisted reproduction improving the developmental competence of aged oocytes and increasing the odds of implantation and subsequent delivery.

Identification of novel virulence-related genes in Aeromonas hydrophila by screening transposon mutants in a Tetrahymena infection model.

Outbreaks of motile Aeromonad septicemia (MAS) in fish caused by sequence type (ST) 251 Aeromonas hydrophila have become a prominent problem for the aquaculture industry. The pathogenesis of A. hydrophila is very complicated, and some virulence factors remain to be identified. In this study, to identify novel virulence-related factors, ST251 A. hydrophila strain NJ-35 was used as the parental strain to construct a mutant library comprising 1030 mutant strains by transposon insertion mutagenesis. Subsequently, 33 virulence-attenuated transposon insertion mutants were identified using Tetrahymena and zebrafish as model hosts in sequence. Thermal asymmetric interlaced (Tail)-PCR and Southern blot analysis identified 21 single transposon insertion sites. Seven of the insertion sites are located in non-coding regions, whereas the other 14 insertion sites are located in genes, including aroA, rmlA, rtxA, chiA and plc. All insertion mutants exhibited attenuated virulence in Tetrahymena and zebrafish. Furthermore, the relationship of two genes, chiA and trkH, to virulence was confirmed by gene inactivation and subsequent restoration assays. This study provides new information about the genetic determinants of A. hydrophila pathogenicity and validates the Aeromonas-Tetrahymena co-culture model for high-throughput screening of A. hydrophila virulence factors.

Defining conditions for the co-culture of Caco-2 and HT29-MTX cells using Taguchi design.

INTRODUCTION: The co-culture of Caco-2 and HT29 cells for testing intestinal drug and nutrient transport and metabolism provides the presence of both absorptive and goblet cells, both of which have different culture requirements for optimal growth and function. The research on the co-culture of Caco-2 and HT29 cells is very limited in respect to refining specific conditions that reduce intra- and inter-laboratory variations. In the present study we reported conditions that enable reproducible results to be obtained for drug permeability using in vitro co-culture of Caco-2 and HT29-MTX based on Taguchi experimental design. METHODS: The selection of four factors that specified cell culture conditions, namely culture medium, seeding time, seeding density, and Caco-2:HT29-MTX ratio on TEER value and individual permeability coefficients of propranolol, ketoprofen and furosemide was established. Based on the selected conditions for co-culture, we also confirmed the functionality of the final chosen culture condition using nitric oxide as an indicator of intestinal inflammation. RESULTS: Choice of cell culture time and culture medium represented two of the most important factors that affected TEER values and the permeability coefficients of the model drugs. On the other hand, the seeding density and the Caco-2:HT29-MTX ratio exerted no significant influence on TEER values and the drug permeability coefficients. No absolute optimal cell culture condition could be obtained for all drugs; however subsequent confirmation experiments concluded that excellent precision for TEER values and drug permeability coefficients was obtained from the two operators using the following combination of conditions, namely an initial seeding density of 1 x 10(5) Caco-2 and HT29-MTX cells/cm(2) at a ratio of 9:1, followed by a 21day culture time in MEM medium. Finally, functionality of the co-culture model system using the above selected in vitro conditions resulted in comparable nitric oxide synthesis to that of a Caco-2 cell monolayer. DISCUSSION: Taguchi experimental design enabled us to define a combination of in vitro culture conditions that resulted in excellent operator reproducibility for determining drug permeability coefficients in a Caco-2 and HT29-MTX co-culture system. Moreover, the selected conditions used in co-culture of absorptive and goblet intestinal cells did not compromise the synthesis of nitric oxide, an indicator of inflammation, measured in Caco-2 monolayers.

Efecto del co-cultivo sobre el desarrollo temprano de embriones bovinos producidos in vitro / Co-culture effect on early development of in vitro bovine embryos

Objetivo. Estudiar el efecto del cocultivo con células oviductales sobre el porcentaje de clivaje 48 horas post inseminación (hpi) de embriones bovinos en bajas tensiones de oxígeno. Materiales y métodos. Se recolectaron ovarios de matadero para la extracción de los ovocitos que fueron puestos en medio TCM 199 suplementado con hormonas, se fertilizaron con semen criópreservado y se cocultivaron en medio CR1aa con células de oviducto durante 48 horas. Se evaluó el porcentaje de clivaje total y el porcentaje de clivaje por estadios de 2-4 células y 5-8 células. La viabilidad de las células para el cocultivo se determinó por observación del movimiento ciliar y observación de monocapa. Los tratamientos fueron T1: células de oviducto + oxígeno 20%; T2: células de oviducto + oxígeno 7%; T3 y T4 fueron controles sin células para ambas concentraciones de oxígeno. Resultados. En cuanto al porcentaje de clivaje no hubo diferencia significativa entre los cuatro tratamientos, pero hubo una tendencia a mayor clivaje para los embriones cocultivados con células y 20% oxígeno. Conclusiones. La utilización de altas tasas de oxígeno (20%) en los sistemas de cococultivo con células oviductales tienden a mejorar los porcentajes de clivaje a las 48 hpi.

Stromal cell lines from mouse aorta-gonads-mesonephros subregions are potent supporters of hematopoietic stem cell activity.

The aorta-gonads-mesonephros (AGM) region autonomously generates the first adult repopulating hematopoietic stem cells (HSCs) in the mouse embryo. HSC activity is initially localized to the dorsal aorta and mesenchyme (AM) and vitelline and umbilical arteries. Thereafter, HSC activity is found in the urogenital ridges (UGs), yolk sac, and liver. As increasing numbers of HSCs are generated, it is thought that these sites provide supportive microenvironments in which HSCs are harbored until the bone marrow microenvironment is established. However, little is known about the supportive cells within these midgestational sites, and particularly which microenvironment is most supportive for HSC growth and maintenance. Thus, to better understand the cells and molecules involved in hematopoietic support in the midgestation embryo, more than 100 stromal cell lines and clones were established from these sites. Numerous stromal clones were found to maintain hematopoietic progenitors and HSCs to a similar degree as, or better than, previously described murine stromal lines. Both the AM and UG subregions of the AGM produced many supportive clones, with the most highly HSC-supportive clone being derived from the UGs. Interestingly, the liver at this stage yielded only few supportive stromal clones. These results strongly suggest that during midgestation, not only the AM but also the UG subregion provides a potent microenvironment for growth and maintenance of the first HSCs.

Round spermatid separation and in-vitro maturation.

OBJECTIVE: To combine 2 methods; spermatid isolation and in-vitro maturation to improve their quality and enhance their ability of fertilization. METHODS: A discontinuous Percoll gradient was used to separate immature germ cells. Co-culture with Vero cells was attempted to convert round spermatids into more mature forms. In total 87 spermatids were studied. RESULTS: Of a final number of 77 round spermatids only 12 (15.5%) showed a certain degree of maturation in 3 out of 7 patients (42%). Of those 12 maturing spermatids, only 4 developed to an early elongated spermatid stage Sc1, but without flagella. CONCLUSION: Considering the limited in-vitro round spermatid maturation achieved in this study, the low fertilization and pregnancy rate with spermatids in general and round spermatids in particular, further refinements of this technology have to be achieved before its regular implementation in routine clinical practice is justifiable.

Efecto del día de transferencia embrionaria sobre la tasa de implantación de blastocistos humanos desarrollados en co-cultivo / Effect on the day of embryonic tranfer on the rate of installation of human blastocysts developed in co-cultivation

Se ha descripto que la técnica de co-cultivo tendría un efecto beneficioso sobre los procedimientos de Fertilización In Vitro (FIV) mejorando tanto la calidad embrionaria como así también la tasa de desarrollo hasta el estadio de blastocisto. Hemos estudiado dos grupos de pacientes a las que se transfirieron blastocistos obtenidos luego de 5 a 6 días en co-cultivo. Los resultados indicaron que se logra una elevada tasa de implantación y embarazo luego de transferir blastocistos expandidos de día 5º. No se obtuvo implantación ni embarazo en pacientes que recibieron blastocistos de día 6º. El co-cultivo permite identificar con más certeza a aquellos preembriones con mayor potencial de viabilidad

The quality of human embryo growth is improved when embryos are cultured in groups rather than separately.

OBJECTIVE: To determine the effect of culturing human embryos in groups on cleavage rates, morphology grades, and embryo scores when compared with embryos cultured singly. DESIGN: Prospective. SETTING: The IVF-ET program of the Pennsylvania State University, Department of Obstetrics and Gynecology, Hershey Medical Center, Hershey, Pennsylvania. PATIENTS: Fifty-five infertile women who each had at least five zygotes underwent IVF-ET. INTERVENTIONS: Zygotes from each patient were allocated to be cultured singly and in groups. MAIN OUTCOME MEASURES: Cleavage rate, morphology grade, and embryo score. RESULTS: Grouping embryos significantly enhanced cleavage rates and embryo scores but not morphology grade as compared with embryos grown singly. Additionally, the size of the groups correlated positively with cell number and embryo score but not the morphology grade. CONCLUSION: Culturing human embryos in groups enhances the quality of their growth by increasing the cleavage rates and embryo scores. Because pregnancy rates are improved by transferring embryos with higher embryo scores, coculturing human embryos may be a way of enhancing pregnancy rates.