13 April 2004 A3 writes: I should add my cent and a half about the "radio tagged blood" story. I don't work on platelets, humans, etc. but to the best of my understanding here's what may be going on.� The current state of the art for platelets is that they're only good for something like a week, but recently a way was worked out to dry them out and use them for up to two years.� The workshop you found out about looks like it would be oriented toward working out the best way to do tests to find out how well such altered platelets would really work, in "healthy volunteers" as described in the notice.� The radio-labeling is desirable because it provides a way to track what happens to the platelets during such an experiment within the volunteer's body, hopefully without requiring the person to be exposed to very many of these freeze-dried platelets in the process in case they aren't so good for him.� It would NOT (I assume) be used on anyone going to the hospital and getting routine treatment. Here's a story from Nature Science Update (www.nature.com/nsu/) Instant stem cells - just add water Dried cells could aid remote medicine. 19 December 2003 HELEN PEARSON Cell membranes crack if they are overly parched. � SPL Researchers are honing a technique to create dried stem cells that can be revived just by adding water. The 'instant' cells might make mobile therapies for remote regions or the battlefield. Because some stem cells can make fresh bone, muscle or blood, doctors hope to use them to repair tissues. But, like transplant organs kept on ice, their shelf life will be limited without an easy way to store and transport them. Today researchers save stem cells by freezing them in expensive vats of liquid nitrogen at -140 �C. To stop damaging ice crystals forming inside the cells, they bathe them in a toxic chemical such as dimethylsulphoxide. This must be washed off before cells can be used. Air drying Several scientists are looking for a way to air-dry cells, comparable to the technique that turns grapes to raisins. Dried stem cells might be stored in portable packets that can be ripped open and their contents mixed with water at the scene of an accident, says Ann Oliver of the Center for Biostabilization at the University of California, Davis. Oliver dreams of plastering desiccated stem cells onto a bone-shaped matrix and then adding water and growth proteins to trigger the cells to divide and form new bone, ready for a transplant. "It's a pie-in-the-sky goal," she admits. In their latest advance, Oliver and her colleagues dried out mesenchymal stem cells, sucked from bone marrow. After drying, approximately 17-25% of the sample was water. When rehydrated immediately afterwards, up to half grew and divided, Oliver revealed at this week's American Society for Cell Biology meeting in San Francisco. Her team soaked the stem cells in an anti-freeze sugar called trehalose. This sugar sloshes around in organisms that survive dehydration, such as brine shrimp, baker's yeast and certain drought-resistant resurrection plants. Adding a second protective compound called arbutin boosted cell survival further. Researchers have used trehalose before to preserve other cells. The real breakthrough, says Fred Levine of the University of California, San Diego, will come when cells can be revived after several weeks on the shelf. Levine says his group are achieving similar results as Oliver's, also with mesenchymal stem cells. What's more, 80-90% of rehydrated cells must be revived before the technique can be put into practice, says Mark Pittenger of Osiris Therapeutics in Baltimore, Maryland, whose company works with Oliver. "It's unclear when it'll come along," he says. Wet ones Dehydration must remove as much water as possible so that cells' metabolism is halted, otherwise they churn out waste that poisons their surroundings. But cell membranes crack if they are overly parched. Researchers are experimenting to strike the right balance. Stem cells have nuclei that must be perfectly preserved Oliver and her team used a similar technique to dry and store blood platelets for transfusions for up to two years, without causing them any obvious harm. Transferring the technique to stem cells is tricky because, unlike platelets, they have nuclei that must be perfectly preserved. � Nature News Service / Macmillan Magazines Ltd 2003 10 April 2004 A. writes: You might want to change the title of that referenced article.� The blood is not "radio" tagged.� Rather the design has radioactive "probes" within it that allow it to be traced through the body and assess the quality. A2 writes: I saw the FDA posting for the radio-labeled blood study at the top of your page.� As a nuclear pharmacist, I have radio-labeled thousands of patient's�blood samples, either labeling platelets with In-111, white blood cells with In-111 or Tc-99m, or red blood cells with Cr-51. Radio-labeled blood components are typically used for diagnosis of various disease states. (In-111, Tc-99m, and Cr-51 are radioactive isotopes of Indium, Technetium, and Chromium). Normally, your site doesn't deal� with subjects like this.� What interested you�about this particular posting? Cryptome: Agreed, the title overreaches: it's a response to various radio-frequency tagging cum spying controversies. Radioactive is not radio-frequency but the tracing of blood quality might be perceived as a kind of spying to those nervous about double-crossing databases. Do you know how patient privacy is maintained during the probes and analysis of them -- from point of insertion on through the studies and onto to follow-ups? That would be useful information to add to the FDA notice. 9 April 2004 Source: http://www.access.gpo.gov/su_docs/aces/fr-cont.html ----------------------------------------------------------------------- [Federal Register: April 8, 2004 (Volume 69, Number 68)] [Notices] [Page 18593-18594] From the Federal Register Online via GPO Access [wais.access.gpo.gov] [DOCID:fr08ap04-64] ----------------------------------------------------------------------- DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Use of Radiolabeled Platelets for Assessment of In Vivo Viability of Platelet Products; Public Workshop AGENCY: Food and Drug Administration, HHS. ACTION: Notice of public workshop. ----------------------------------------------------------------------- The Food and Drug Administration (FDA) is announcing a public workshop entitled ``Use of Radiolabeled Platelets for Assessment of the In Vivo Viability of Platelet Products''. The goal of the workshop is to orient the transfusion community to a new approach for assessing the quality of platelet products through radiolabeling studies in healthy human volunteers. Date and Time: The public workshop will be held on May 3, 2004, from 8 a.m. to 5 p.m. Location: The public workshop will be held at Lister Hill Auditorium, Building 38A, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD 20894. [[Page 18594]] Contact Person: Joseph Wilczek, Center for Biologics Evaluation and Research (HFM-302), Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448, 301-827-6129, FAX: 301-827-2843, e-mail: wilczek@cber.fda.gov. Registration: Send registration information (including name, title, firm name, address, telephone, and fax number) to the contact person by April 23, 2004. Early registration is recommended because seating is limited to 176 participants. Registration will be done on a space available basis on the day of the workshop, beginning at 7:15 a.m. There is no registration fee. If you need special accommodations due to a disability, please contact Joseph Wilczek (see Contact Person) at least 7 days in advance. SUPPLEMENTARY INFORMATION: FDA, in co-sponsorship with the Hitchcock Foundation, is sponsoring a public workshop on the development of a new standard for assessing the in vivo quality of platelet products through radiolabeling studies. The workshop objectives are to review current methods in radiolabeling studies, to propose a new approach that will set the performance of fresh platelets as a gold standard, to present data on application of a new standard, and to discuss the development of a novel experimental protocol. The public workshop agenda is posted on FDA's Internet at http://www.fda.gov/cber/meetings/radioplt0504.htm. Transcripts: Transcripts of the workshop may be requested in writing from the Freedom of Information Office (HFI-35), Food and Drug Administration, 5600 Fishers Lane, rm. 12A-16, Rockville, MD 20857, approximately 15 working days after the meeting at a cost of 10 cents per page. In addition, the transcript will be placed on FDA's Internet at http://www.fda.gov/cber/minutes/workshop-min.htm. Dated: April 2, 2004. Jeffrey Shuren, Assistant Commissioner for Policy. [FR Doc. 04-8023 Filed 4-7-04; 8:45 am] BILLING CODE 4160-01-S