Outcomes of vitrified-warmed day-4 embryos after day-3 cleavage-stage biopsy.

The objective of this study was to compare the post-warming survival rates of biopsied and non-biopsied day-3 embryos vitrified on day 4 and to evaluate the clinical outcomes of following transfers. This study included 18 preimplantation genetic diagnosis (PGD) patients and 18 non-PGD patients treated between January 2005 and January 2009 who had not achieved live births during their fresh embryo-transfer cycles and whose surplus embryos were cryopreserved on day 4. The embryo survival rate after warming in the PGD and non-PGD groups was similar (53/59, 89.8% versus 55/64, 85.9%, respectively; difference of 3.9% 95% CI -7.3 to 13.4). Vitrified embryo-transfer cycles yielded no significant differences between PGD and non-PGD groups in implantation rates (12/46, 26.1% versus 9/47, 19.1%, respectively; difference of 6.9%, 95% CI -9.7 to 22.2), clinical pregnancy rates (11/18, 61.1% versus 9/18, 50%, respectively; difference of 11.1%, 95% CI -20.6 to 40.6) and live birth rates (9/18, 50% versus 6/18, 33.3%, respectively; difference of 16.7%, 95% CI -15.1 to 44.8). These results showed that, in PGD cycles, embryos can be vitrified effectively on day 4 after biopsy on day 3. The objective of this study was to compare the post-warming survival rates of biopsied and non-biopsied day-3 embryos that vitrified on day 4 and to evaluate the clinical outcomes of following transfers. This retrospective study included 18 preimplantation genetic diagnosis (PGD) and 18 non-PGD patients treated between January 2005 and January 2009 who had not achieved live births during their fresh embryo transfer cycles and whose surplus were frozen on day 4. After warming in frozen embryo-transfer cycles, embryo survival with respect to embryo grades, implantation, clinical pregnancy and live birth rates were compared. The embryo survival rate after warming in the PGD group was similar to the survival rate in the non-PGD group (53/59, 89.8% versus 55/64, 85.9%, respectively; difference of 3.9%, 95% CI -7.3 to 13.4, P=0.701). Frozen embryo transfer yielded no significant differences between PGD and non-PGD groups in implantation rates (12/46, 26.1% versus 9/47, 19.1%, respectively; difference of 6.9%, 95% CI -9.7 to 22.2, P=0.581), clinical pregnancy rates (11/18, 61.1% versus 9/18, 50%, respectively; difference of 11.1%, 95% CI -20.6 to 40.6, P=0.737) or live birth rates (9/18, 50% versus 6/18, 33.3%, respectively; difference of 16.7%, 95% CI -15.1 to 44.8, P=0.499). These results showed that, in PGD cycles, embryos can be vitrified effectively on day 4 after biopsy on day 3.

Establishment and characterization of human embryonic stem cell lines, Turkey perspectives.

Human embryonic stem cells (hESC), which are derived from the inner cell mass (ICM) of blastocyst stage embryos, are of great importance because of their unpredictable two unique features: their differentiation ability into all types of cells derived from three germ layers and their potentially unlimited capacity of self renewing with stable karyotype. These distinguished properties make hESC very promising cell source for regenerative medicine, tissue replacement therapies, and drug screening studies as well as genomics. However, due to the several technical problems, such as risk of teratoma formation, immune response, and unknown genetic pathways for lineage specific differentiation, and ethical drawbacks of their using in clinical treatments, hESC researches are still waiting to advance beyond to animal trials and drug studies. During the last decade, more than 300 new hESC lines have been derived and published by researchers worldwide. However, despite their similar well-known unique properties, recent studies reported that hESC lines have very individual properties and are differed from each other with regards to their differentiation ability and gene expression profiles. Therefore, all hESC lines should be characterized in detail and then registered in a stem cell bank for generating global database. In this report, the characteristic of hESC lines, which were established in Istanbul Memorial Hospital between 2003 and 2005, and derivation methods were described in detail to inform researchers and to facilitate new prospective cooperative studies.

Establishment and characterization of new human embryonic stem cell lines.

Human embryonic stem cells (hESC), with their ability to differentiate into all cell types in the human body, are likely to play a very important therapeutic role in a variety of neurodegenerative and life-threatening disorders in the near future. Although more than 120 different human embryonic stem cell lines have been reported worldwide, only a handful are currently available for researchers, which limits the number of studies that can be performed. This study reports the isolation, establishment and characterization of new human embryonic stem cell lines, as well as their differentiation potential into variety of somatic cell types. Blastocyst-stage embryos donated for research after assisted reproductive techniques were used for embryonic stem cell isolation. A total of 31 blastocysts were processed either for immunosurgery or direct culture methods for inner cell mass isolation. A total of nine primary stem cell colonies were isolated and of these, seven cell lines were further expanded and passaged. Established lines were characterized by their cellular and colony morphology, karyotypes and immunocytochemical properties. They were also successfully cryopreserved/thawed and showed similar growth and cellular properties upon thawing. When induced to differentiate in vitro, these cells formed a variety of somatic cell lineages including cells of endoderm, ectoderm and mesoderm origin. There is now an exponentially growing interest in stem cell biology as well as its therapeutic applications for life-threatening human diseases. However, limited availability of stem cell lines as well as financial or ethical limitations restrict the number of research projects. The establishment of new hESC lines may create additional potential sources for further worldwide and nationwide research on stem cells.