Cryptosporidiosis outbreak in the UK

THE LANCET

SCIENCE AND MEDICINE

or the first time, cryopreserved umbilical-cord blood has been used for gene therapy in a clinical setting. An Israeli–Italian team transplanted genetically altered cells into a infant on Feb 15. The researchers will know if the treatment has worked within a few months. Shimon Slavin, Arnon Nagler, and Elizabeth Naparstek (Hadassah Medical Center, Jerusalem, Israel), and Claudio Bordignon and Alessandro Aiuti (HS Raffaele Scientific Institute, Milan, Italy) transplanted about 50 mL of genetically modified, cryopreserved cord blood into an infant with adenosine deaminase (ADA)-deficient severe combined immunodeficiency disease. The infant’s only sibling had died from the same inherited disease. Cord blood was frozen at the time of the second child’s birth, in anticipation of the need for an autologous transplant. “Frozen cord blood has been transplanted before and cord blood is proving to be an excellent medium for expression of introduced genes, but this is the first time that cryopreserved umbilical cord blood cells have been genetically modified with retroviral vectors and engrafted in a patient”, says Nagler, head of the Israeli national cord blood bank. “The implications [of our work] are very important”, says Bordignon. “Previously, diagnosis had to be made prenatally to use fresh cord blood at birth, but if the cryopreserved blood proves itself, we open up a whole range of treatment possibilities”.

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Rachelle H B Fishman

Cryptosporidiosis outbreak in the UK s of March 4 there are 32 confirmed cases of cryptosporidiosis in the area of the UK served by Three Valleys Water. Residents in the area (Watford, St Albans, and parts of North London) have been advised to boil water used for drinking, cleaning their teeth, and preparing food. Three Valleys Water say there is no direct link to the water supply but the discovery of cryptosporidium in a few water samples prompted the company to introduce emergency ozone dosing at one of its water treatment works and to issue advice to boil water. 䡺

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Vol 349 • March 8, 1997

First Dolly the sheep, now multiple monkeys

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ard on the heels of the report of a sheep being cloned from adult sheep cells (Nature 1997; 385: 810–13) has come news in the lay press of an Oregon group “cloning” a monkey. In fact, the group, whose work is not published in a peerreviewed journal, have not cloned a monkey but have laid the foundations for producing genetically identical primates from embryo cells by nuclear transfer. This, says Jerry Robinson, director of the Primate Centers Program at the US National Institutes of Health, means that “Now we can produce identical monkeys, which will allow for research data that are more certain, quicker and cheaper in studies on such problems as AIDS”. Don Wolf (Oregon Regional Primate Research Center, Beaverton, OR, USA) and his team produced two monkeys by transferring cells from two distinct embryos, the cells of which they had separated at the eight-cell stage, into enucleated cells. Since the cells from which they developed were from two separate embryos, each fertilised in vitro by different sperm, the monkeys, born last August, are not identical. However, “We have proven the technology”,

says Wolf, “and now, to get genetically identical animals, it will only be a matter of transferring embryos created from a single embryo”. Dolly, the sheep, reported last week by Ian Wilmut and his colleagues at the Roslin Institute (Roslin, UK) and PPL Therapeutics (also in Roslin) is, however, a true clone—her genomic DNA is identical to that of her genetic parent. Dolly was produced by taking the nucleus from an adult mammary gland cell and transferring it into an enucleated unfertilised egg. DNA microsatellite analysis confirmed that the lamb’s genetic material was derived from the donor nucleus. These results answer a question that has fascinated developmental biologists for years—namely, do adult cells retain all the genetic material necessary to rebuild a whole animal? Dolly’s genesis has raised a large number of questions (see Editorial p 661) but as discussed by Colin Stewart in an accompanying News and Views in Nature, the ability to clone a sheep does not necessarily mean that the technique can be easily adapted to human cloning. Jane Bradbury

Transdermal nicotine helps in ulcerative colitis improved. Patients in the nicotine ransdermal nicotine can help group showed significant improvepatients with chronic active ment in stool frequency, in sigmoidoulcerative colitis if it is given in high scopic findings, and in physician doses, say researchers at the Mayo assessment. Rectal Clinic (Rochester, MN, bleeding also improved USA). in the nicotine group, In the study, 64 but this trend did non-smoking patients not achieve statistical were randomised to significance. receive either placebo Lead author William or transdermal nicotine Sandborn says the new (Ann Intern Med 1997; study should be consid126: 364–63). Patients ered a “very strong taking nicotine were confirmatory study” of started on 11 mg/day the 1994 paper by for the first week and Rupert Pullan et al (N then continued on Engl J Med 1994; 330: the highest dose they Multipurpose patch 811–15). “There are could tolerate (up to now two carefully conducted, 22 mg/day). All the patients had placebo controlled trials that demonchronic active ulcerative colitis strate that the high-dose patch is refractory to first-line therapy. effective in inducing improvement— After 4 weeks of treatment, 12 of at the minimum—in patients with the 31 nicotine-treated patients active ulcerative colitis.” (39%) showed clinical improvement but only 3 of the 33 patients (9%) receiving the placebo (p =0·007) had Michael McCarthy

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Science Photo Library

Frozen cord blood used for human gene therapy

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