X-Message-Number: 10737 Date: Tue, 10 Nov 1998 08:55:22 -0800 From: "Joseph J. Strout" <> Subject: more on trehalose I did a little lit search on trehalose and cryopreservation. A few items sound quite interesting... Beattie, GM; Crowe, JH; Lopez, AD; Cirulli, V; Ricordi, C; Hayek, A. Trehalose: a cryoprotectant that enhances recovery and preserves function of human pancreatic islets after long-term storage. Diabetes, 1997 Mar, 46(3):519-23. From the abstract: We have developed a method to cryopreserve islets with excellent survival of endocrine cells. Current methods use DMSO as cryoprotectant. Our method involves introducing both DMSO and the disaccharide trehalose into the cells during cooling. Uptake and release of trehalose occurred during the thermotropic lipid-phase transition measured in pancreatic endocrine cells between 5 degrees and 9 degrees C, using [14C]trehalose. Recovery of adult islets after cryopreservation with 300 mmol/l trehalose was 92 vs. 58% using DMSO alone. In vitro function, in terms of insulin content and release in response to secretagogues, was indistinguishable from fresh islets. Grafts from islets cryopreserved with trehalose contained 14-fold more insulin than grafts from islets cryopreserved without trehalose. Results with human fetal islet-like cell clusters (ICCs) were more pronounced: recovery from cryopreservation was 94%, compared with 42% without trehalose. ... Thus, the addition of trehalose to cryopreservation protocols leads to previously unobtainable survival rates of human pancreatic endocrine tissue. Saha, S; Otoi, T; Takagi, M; Boediono, A; Sumantri, C; Suzuki, T. Normal calves obtained after direct transfer of vitrified bovine embryos using ethylene glycol, trehalose, and polyvinylpyrrolidone. Cryobiology, 1996 Jun, 33(3):291-9. (UI: 96260185) From the abstract: ...embryos were vitrified using one of the three treatments (Treatment A, 40% ethylene glycol (EG); treatment B, 40% EG + 11.3% trehalose; and treatment C, 40% EG + 11.3% trehalose + 20% PVP and rehydrations) was performed directly in mPBS. Highest development (84.1%) and hatching rate (68.2%) were obtained when embryos were vitrified with the vitrification solution used in treatment C. Yokomise, H; Inui, K; Wada, H; Ueda, M; Hitomi, S. Long-term cryopreservation can prevent rejection of canine tracheal allografts with preservation of graft viability. Journal of Thoracic and Cardiovascular Surgery, 1996 May, 111(5):930-4. From the abstract: Six to 10 rings of the trachea were removed from donor dogs (n = 12), immersed in the preservative solution [containing trehalose], and cryopreserved in a deep freezer at -85 degrees C for 285 +/- 28 days (cryopreservation group). Five rings of the mediastinal trachea of recipient dogs were removed. The cryopreserved tracheas were thawed and transplanted to replace the excised mediastinal tracheas... The anastomotic site and graft were covered with an omental pedicle in both groups. In the cryopreservation group, every animal, except one that was killed for pathologic examination, survived more than 2 months. All the grafts of this group were viable, and no stenosis or tracheomalacia was observed. These results suggest to me that trehalose may have value not just in above-freezing preservation, but as a cryoprotectant for long-term storage as well. (And FWIW, several of the abstracts I read reported that polyvinylpyrrolidone (PVP) may work even better in some cases, either alone or in combination with trehalose.) Speaking of such things, I was unable to make the 21CM seminar last Sunday. Are any of the reports available? Or any attendees who would care to summarize? Best regards, -- Joe ,------------------------------------------------------------------. | Joseph J. Strout Department of Neuroscience, UCSD | | http://www.strout.net | `------------------------------------------------------------------' Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=10737