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Milan, July 5 (AdnKronos Health) – This is a first step, the general test that precedes the biggest challenge: save the Northern White Rhinoceros from extinction now certain, since on the planet whole there are only two females of this species. The birth of the child of hope is always a dream and the obstacles to overcome are not rare, but an international team of scientists – with the Italian Cesare Galli in the forefront, & # 39; ; dad & # 39; of the first cloned bull Galileo and first mare "photocopy" Prometea – works to see the light. The first step has been taken, researchers from around the world announced yesterday in the journal "Nature Communications": the first hybrid embryos, derived from white rhinoceros oocytes and white rhinoceros spermatozoa, have were successfully created in test tubes come from cryopreserved samples, taken from males and then died.And in the gel are now also kept the precious blastocisti, waiting to be transferred to surrogate mothers. "We plan to have the first pregnancy in the year," says AdnKronos Salute Galli, founder of Avantea, an advanced technologies laboratory for animal breeding and biotechnology research based in Cremona. The Rhinos gestation lasts 16 months and is looking forward to the moment when the first "hybrid" puppy will come into the world. This will be the proof that it is technically possible to give the descent to the white rhinoceros of the North. Only then, when you have the certainty that all the stages of the complicated path of rebirth can go to the port, everything will be attempted for a 100% North descendants. Meanwhile, Thomas Hildebrandt of the German Department of Reproduction Leibniz The Institute for Zoological and Wildlife Research in Berlin, the first step is a first: "These are the first rhinoceros embryos produced in vitro and which have very chances of giving birth to a pregnancy once implanted in a surrogate mother ". What is? It will be the females of the South to give a hand to those of the North, bringing in their belly the little ones and making mothers in the future to a population of the North in formation. Unlike the northern white rhino, there are about 21,000 specimens of southern species in southern Africa today. When the scientists' work was proposed late 2017 for publication, 17 female oocytes from the southern white rhinoceros, "hosts" of European zoos, were fertilized with seeds of males of the same subspecies obtaining 3 embryos, while 13 southern oocytes had been fertilized with the northern seed and had given 4 hybrid embryos. But the team's business has progressed and "we now have two more embryos produced with northern seeds in the last month," adds Galli. The cryopreserved embryos are in the Cremona laboratory. The researchers had to adapt badisted reproductive technologies used in horses to the particular circumstances of rhinos and develop pioneering procedures. The first node to address was oocyte collection. These pachyderms have unsealable skin and to remove them, international experts have used a patented device of nearly 2 meters, eco-controlled and placed transrectally. When a follicle appeared on the screen of the portable ultrasound, a special needle was activated, which perforated the intestinal part of the ovary and collected the oocyte. The same strategy (with a catheter) will be used for the transfer of embryos to surrogate mothers. The oocytes were sent to Avantea. "In our laboratory – Galli says – we were able to develop procedures to mature oocytes, fertilize them by intracytoplasmic injection of sperm (Icsi) and cultivate them. We had for the first time rhino blastocysts – initial phase of Embryo – developed in vitro, similar to what we usually do for cattle and horses, because the sperm of the North was of poor quality, we used a protocol for activation after the ICSI ". STRATEGY: ASSISTED REPRODUCTION AND STEM CELLS – The team also derived two blastocystic stem cells from the Southern subspecies with "all the typical characteristics of embryonic stem cells, undifferentiated cells and a high degree of differentiation in different cell types "Says Galli. The cells that were sent to Berlin where they work on the differentiation of gametes. Stem cell research is also an important step for the northern white rhinoceros rescue mission. Since there are only two females and the sperm comes from only four males, the only technique of badisted reproduction and in vitro fertilization would not be enough to create a self-sustaining population with the necessary genetic variability. That's why we are working on an extra approach with the super experts of "baby cells". "In the future – explains Sebastian Diecke of the Max Delbrück Center for Molecular Medicine of the Helmholtz Association (Berlin) and Katsuhiko Hayashi of the Department of Biology and Medicine of Stem Cells of Kyushu University ( Japan) – Our goal is to produce primordial germ cells in vitro from induced pluripotent stem cells (iPS) obtained from cryopreserved somatic cells in the past from 13 individuals of Nwr (Northern White Rhino). "Later, they will be transformed into oocytes and spermatozoa". "We think it's a sustainable operation – says Galli – The results of a study published late May by colleagues in San Diego have indeed shown that the genetic variability of Nwr's 13 individuals is greater than that of the entire population of the South ". "The successful development of a hybrid embryo – adds Jan Stejskal, director of international projects at Safari Park Dvur Králové in the Czech Republic – is an important step towards the first birth of a northern white rhino by artificial propagation techniques, genetic information comes from the northern white rhinoceros ". "The hybrid embryos obtained are beautiful and there are good hopes," says Galli. By combining stem cell research with the new badisted reproductive technology, the international team emphasizes: "We will provide a model for saving seriously endangered species, now reduced to numbers that make conventional conservation efforts impossible. The situation of white rhinos in the North is "hopeless". The population grew from 2,000 individuals in the 1960s to the only two survivors of today, "mother and daughter aged 18 and 25 happily still of childbearing age," says Galli. The last two females of Nwr, on which the subspecies depend, were born in Dvur Králové and currently reside in the Ol Pejeta Nature Reserve, near Mount Kenya. And now the authorities are waiting for permits to collect the oocytes. "We hope to have permission in the year" to achieve the decisive goal of creating pure Northern embryos. Hoping, maybe in a period of five years, see the puppy born hope. FRAMEWORK AND DONATIONS, HUNTING FUND – Scientists have never stopped believing, even to auction a framework for getting funds to spend on the business. In March 2018, the news came of the disappearance of the last man, Sudan, who died of old age without being able to see born another specimen of his family, now reduced to only two members: the two women Fatu and Najin. "This research is revolutionary – observes Steven Seet, head of communication at the German Leibniz Institute for Zoological and Wildlife Research (Leibniz-Izw) in Berlin – We are witnessing the development of a method that can help to compensate for the negative impact of human beings on nature We are very grateful for the donations received from people who support our race against time.We hope that the results obtained will convince more people and public authorities than this. new approach works and is effective, worthy of support ". Every gift is welcome, that's the message. For the moment, Leibniz-Izw has auctioned not only a painting representing the white rhinoceros, by the Hungarian painter Anton Molnár (sale which brought the 20 thousand euros to the cause, Galli reminds), but also a 3D printing of a rhinoceros skull from the Polytechnic School of Berlin. "We have worked with reduced budgets, we are self-financing and we are getting some small private donations – explains Galli all – AdnKronos Health – I remember for example Sumatra, where there is a company that runs plantations for the first time. palm oil and that is subtracted in Borneo pachyderm habitat "and the critics did not fail." Some say that it is too late, that the northern white rhino is now technically extinct, that even though we save it does not survive in a compromised environment, "says the tricolor scientist.According to experts, the northern white rhinos are the most endangered mammals on the planet and all conservation efforts to save this species" were thwarted by human activities such as poaching, civil wars and loss of habitat. "Among the observations received from the team of scientists eager to prevent their extinction One, also, has raised the objection that money is wasted that could be used to save other species with conventional approaches, Galli says. The path that led to the publication of scientific data was also rigorous. The experts who deal with the revision of the content of the work have asked for different controls on the authors, or even a kind of "paternity test" for the embryos obtained in test tubes, explains the Italian scientist. "Our results are solid, reproducible and very promising," said Hildebrandt, who has been dreaming of saving the pachyderm for more than 20 years. For Galli, it was "a challenge – he says – I wanted to try something new and never done before". Now, the Italian scientist is turning to the next step: the transfer of embryos created in the laboratory of Cremona to surrogate mothers, white rhinos, who will give the hand to the "cousins" of the North (both subspecies live in nature for more than a thousand kilometers). The first to be born will be a South-North hybrid puppy, dreaming of the arrival of the small '100% North'. "In Prague, in a safari park 20 years ago, there were already hybrid individuals – reminds Galli – They are not very different species, we can cross them.Our Mediterranean buffalo was crossed in China with the marsh and we saw that the animals were fertile, certainly the criticism will still be there, and in any case it is the fact that we did not have another option to save the genome of the white rhinoceros North ". Scientists are not only those who believe in it and also have small supporters on their side. "A 10-year-old girl – Hildebrandt told the Guardian some time ago – gave her piggy bank 100 euros, so the kids really recognize the importance of" the mission ", even though politicians do not do not do it. "
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