Historical Note: Lessons Learned from Developing the First Semi-Defined Medium for Culture of One-Cell Rabbit Embryos to Expanding Blastocysts.

In a review written in 1987 entitled "Pioneering mammalian embryo culture," John Biggers (The mammalian preimplantation embryo: regulation of growth and differentiation in vitro, Plenum Press, New York, 1987) summarized the history of early preimplantation embryo culture as follows "The culture of early mammalian embryos has been studied predominantly in two species: the rabbit and the mouse. Up to 1949, the rabbit was used almost exclusively, with media composed of ill-defined biological fluids. After this time, techniques for the culture of preimplantation mouse embryos rapidly developed using simple, defined media with relatively few components… In the 1960s, there was renewed interest in the culture of early rabbit embryos and a marked difference in the nutritional requirements of the two species was found." This chapter describes the history of the development of the semi-defined medium that stimulated this "renewed interest" referred to above and includes some of the initial difficulties in getting the work published. The phrase "semi-defined medium" is understood here to mean a defined medium (all of whose components are chemically known) supplemented with an undefined component such as albumin.

Development of in vitro fertilization in Australia.

In vitro fertilization (IVF) began in Melbourne in 1970 when Carl Wood founded a research group at the Queen Victoria Hospital. The group reported the first biochemical pregnancy from a transferred IVF embryo in 1973. The group included the Royal Women's Hospital Melbourne, and they were the first to report confirmation of the British group's pregnancies with the use of IVF in natural cycles in 1980. The group then split, and the Monash group pursued fertility drug-induced multiple follicle growth in controlled ovulatory cycles and demonstrated for the first time that they could achieve multiple pregnancies in 1980-1981. This became the basis of a sustainable procedure for treating infertile patients. Successful embryo freezing and thawing methods resulted in pregnancies for the first time and were adopted to cryopreserve excess embryos produced after superovulation. Embryo donation methods were devised for anovulatory patients and were the first reported use of oocyte in vitro maturation techniques (IVM) for polycystic ovarian syndrome patients. Sperm microinjection techniques were pioneered for enabling fertilization for severely infertile men, and micromanipulative techniques were published for embryo biopsy for potential use in preimplantation genetic diagnosis (PGD) for patients with inheritable genetic diseases. The latter research programs were hampered by creation of restrictive embryo research laws in the State of Victoria, handicapping their timely clinical applications. Work on cryopreservation of ovarian tissue for cancer patients enabled clinical application of this for patients at risk of loss of fertility. Vitrification was developed as an alternative to freezing for oocytes and embryos, and this has now replaced the original slow cooling methods. Blastocyst culture systems were devised and optimized to improve IVF success and PGD.

Logros y conflictos en la investigación con células troncales / Achievements and struggles in stem-cell investigation research

Se relatan circunstancias, peripecias y conflictos que han rodeado a varios de los investigadores que han protagonizado el avance de los conocimientos sobre las células troncales a lo largo de cien años, desde el establecimiento del dogma de la inmortalidad celular hasta las técnicas desarrolladas para obtenerlas y utilizarlas en medicina regeneradora. En este último aspecto, se incluye un breve análisis de las perspectivas previstas para las células pluripotentes inducidas (iPS) en relación con las células troncales producidas por transferencia nuclear (NT-ESC) y la producción de embriones humanos por transferencia nuclear de células somáticas (embriones SCNT) (AU)

This report describes events, circumstances and conflicts that have surrounded to several researchers protagonists of the advances on the stem cells knowledge along a hundred of years, from the cell immortality dogma to the discovery of tecnics to produce them to be used in regenerative medicine. At this respect, a brief analysis of the expected outlook for induced human pluripotent cells (iPS) is included and compared with nuclear transfer human stem cells (NTESC) and production of human enbryos by somatic cell nuclear transfer (SCNT embryos) (AU)

History of oocyte and embryo metabolism.

The basic pattern of metabolism in mammalian oocytes and early embryos was established in the 1960s and 1970s, largely in terms of the consumption of oxygen and the utilisation of nutrients present in culture media at the time, mainly glucose, pyruvate and lactate. The potential importance of endogenous fuels was also recognised but was largely ignored, only to be rediscovered quite recently. The 1980s and 1990s saw the arrival of a 'new generation' of culture media, characterised metabolically by the addition of amino acids, an initiative driven strongly by the need to improve embryo culture and selection methods in assisted reproductive technologies. This trend has continued alongside some basic metabolic studies and the general recognition of the importance of metabolism in all aspects of biology. A framework for future studies on oocyte and early embryo metabolism has been provided by: (1) the developmental origins of health and disease concept and recognition of the relationship between development, epigenetics and metabolism; (2) the need to understand cell signalling within, and between the cells of, the early embryo; and (3) the importance of identifying the mechanisms underlying dialogue between the oocyte and early embryo and the female reproductive tract.

IVF culture media: past, present and future.

BACKGROUND: The advances in the world of IVF during the last decades have been rapid and impressive and culture media play a major role in this success. Until the 1980s fertility centers made their media in house. Nowadays, there are numerous commercially available culture media that contain various components including nutrients, vitamins and growth factors. This review goes through the past, present and future of IVF culture media and explores their composition and quality assessment. METHODS: A computerized search was performed in PubMed regarding IVF culture media including results from 1929 until March 2014. Information was gathered from the websites of companies who market culture media, advertising material, instructions for use and certificates of analysis. The regulation regarding IVF media mainly in the European Union (EU) but also in non-European countries was explored. RESULTS: The keyword 'IVF culture media' gave 923 results in PubMed and 'embryo culture media' 12 068 results dating from 1912 until March 2014, depicting the increased scientific activity in this field. The commercialization of IVF culture media has increased the standards bringing a great variety of options into clinical practice. However, it has led to reduced transparency and comparisons of brand names that do not facilitate the scientific dialogue. Furthermore, there is some evidence suggesting that suboptimal culture conditions could cause long-term reprogramming in the embryo as the periconception period is particularly susceptible to epigenetic alterations. IVF media are now classified as class III medical devices and only CE (Conformité Européene)-marked media should be used in the EU. CONCLUSION: The CE marking of IVF culture media is a significant development in the field. However, the quality and efficiency of culture media should be monitored closely. Well-designed randomized controlled trials, large epidemiological studies and full transparency should be the next steps. Reliable, standardized models assessing multiple end-points and post-implantation development should replace the mouse embryo assay. Structured long-term follow-up of children conceived by assisted reproduction technologies and traceability are of paramount importance.

Cryopreservation of oocytes and embryos.

Two hundred years have passed since the first description of supercooled water by Gey-Lussac to the recently high survival rates of embryo and oocytes after vitrification. This review discusses important milestones that have made vitrification the method of choice for oocytes and embryos cryopreservation. We will go through the first cells ever to survive low temperature exposure in the beginning of the last century, the finding of glycerol in the late 1940s and the first mouse and bovine embryos freezing in the 1970s. During the 1980s, embryo vitrification began and the time since is a tribute to the development of oocytes vitrification. Standardization and an automatic vitrification procedure are currently under development. The next evolutionary step in oocyte and embryo cryopreservation will be preserving them in the dry state at room temperature, allowing home storage for future use a reality.

Connections between preimplantation embryo physiology and culture.

PURPOSE: To review the history of experimental embryo culture and how culture media that permitted complete preimplantation development in vitro were first discovered, and the physiological insights gained. METHODS: This article reviews the history of in vitro mammalian embryo culture, in particular the efforts that led to the current generation of successful culture media and how these reflect embryo physiology, highlighting the contributions of Dr. John D. Biggers and his colleagues and students. RESULTS: The culture of mammalian embryos began about a century ago. However, defined media without biological fluids were only developed in the late 1950s, and the first live young born from cultured embryos, using these media, were produced by McLaren and Biggers in 1958. It wasn't until the late 1980s, however, that preimplantation mammalian embryos could generally be cultured in vitro from fertilized eggs to blastocysts. These new media led to insights into embryo physiology, including the importance of cell volume homeostasis to early embryo viability. CONCLUSIONS: The development of successful preimplantation embryo culture media has had a profound effect on assisted reproduction technologies and on research into early embryo physiology.

Symposium in honor of Ralph L. Brinster celebrating 50 years of scientific breakthroughs.

The Symposium speakers comprised a distinguished group of scientists from North America, Europe and Asia. The Keynote address was presented by Michael Brown, Nobel Laureate in Physiology or Medicine (1985), and a plenary lecture was presented by John Gurdon, who within the next months would receive the Nobel Prize in Physiology or Medicine (2012). The first lecture in the series was presented by Richard Palmiter, Ralph’s collaborator for more than 15 years, and he provided an overview of their work together followed by Richard’s subsequent exciting contributions in the area of neurobiology. Seventeen lectures were presented over the two-day Symposium by distinguished scientists, including several of Ralph's former colleagues and students. The topics covered studies on germ cells, the germline, early embryos and their differentiation, as well as exciting and unpublished studies on stem cells and reprogramming. Many of the topics presented arose from foundation experiments in which Ralph participated, and these new developments indicate the dramatic progression of studies in this area. The Symposium program and the complete lectures can be found at the following link: www.vet.upenn.edu/BrinsterSymposium.

Historical background of gamete and embryo culture.

The first tissue culture media were developed nearly 150 years ago by Ludwig and Ringer. These were simple salt solutions, which were initially based on the chemical properties of blood serum. The second generation of culture media was developed more than a century later, in the 1970s, aiming to mimic the reproductive environment. In the 1990s, simplex optimization was used to design the third group of media, to some extent ignoring existing formulations and principles. Simultaneous with the development of culture media, it became evident that it was necessary to carefully control the culture conditions, including temperature, pH, osmolarity, and air quality. Equally important was the development of instruments and tools specifically designed for cell tissue culture such as the inverted microscope, the incubator, the Petri dish, sterile plasticware, the laminar flow cabinet, and air filtration equipment.

Whole embryo culture: a "New" technique that enabled decades of mechanistic discoveries.

Denis New's development of the rodent whole embryo culture (WEC) method in the early 1960s was a groundbreaking achievement that gave embryologists and teratologists an unprecedented degree of access to the developing postimplantation rodent embryo. In the five decades since its development, WEC has enabled detailed investigations into the regulation of normal embryo development as well as a plethora of research on mechanisms of teratogenesis as induced by a wide range of agents. In addition, WEC is one of the few techniques that has been validated for use in teratogenicity screening of drugs and chemicals. In this review, we retrace the steps leading to New's development of WEC, and highlight many examples in which WEC played a crucial role leading to important discoveries in teratological research. The impact of WEC on the field of teratology has been enormous, and it is anticipated that WEC will remain a preferred tool for teratologists and embryologists seeking to interrogate embryo development for many years to come.

Thirty years of IVF.

This paper captures the essence of a session of the Association of Clinical Embryologists' meeting held in Manchester in January 2008. This session was of special significance, since this year marks thirty years since the birth of Louise Brown -- the world's first IVF baby -- at Oldham General Hospital on 25 July 1978. Her birth was a turning point in world history, and launched a new era of scientific, ethical and clinical challenge and discovery, which is as fresh today as it was then. The session focused on historical events and the social climate in which they took place, as well as notable changes in the intervening years, heard from the mouths of those best able to interpret their significance. This paper places the speakers' contributions in context with contemporary and more recent events.