猪胰岛的分离与纯化

目的 探索大规模猪胰岛细胞分离纯化的方法.方法 联合器官切取,胶原酶P主胰管灌注,COBE2991细胞分离机及HCA-Ficoil纯化猪胰岛细胞.通过双硫腙(DTZ)染色,倒置显微镜下计数胰岛细胞的数量和纯度,胰岛素释放试验检测胰岛细胞的分泌功能.结果 消化后平均每条胰腺可平均获得(275 000±20 895)胰岛细胞当量(IEQ),纯化后平均为(230 350±26 679)IEQ,平均每克胰腺组织可获得(2710±229)IEQ,纯化后胰岛细胞平均纯度为(50.2±1.95)%.纯化后的胰岛细胞对胰岛素释放刺激反应良好,高糖(16.7 mmol/L)时胰岛素的释放量为低糖(3.3 mmol/L)时的4.74倍(P≤0.001).结论 成功建立了猪胰岛细胞分离、纯化的方法,纯化的猪胰岛细胞具有良好的生物活性.     

大鼠胰岛分离、纯化技术改良

目的:探讨SD大鼠胰岛分离、纯化的较优方案,并评价依该法分离所得胰岛的生物学特性。方法:以浓度为0.75mg/ml的Ⅺ型胶原酶经胆管充分灌注大鼠胰腺;完整分离后以37℃水浴振荡消化17min,Dextron70不连续密度梯度(1.091、1.081及1.037)离心法分离、纯化胰岛;以DTZ染色鉴定胰岛并计算得率,AO-PI染色检测胰岛活性,糖刺激试验判定胰岛功能,胰岛"细胞免疫细胞化学鉴定"细胞,光镜观察体外培养胰岛的形态学变化。结果:纯化后,每只大鼠胰岛收获量为(743.60±43.07)个,胰岛纯度>90%,胰岛细胞活率>90%。在45min内每10个胰岛细胞在低糖和高糖刺激下分泌的胰岛素浓度分别为(25.35±7.00)μIU/ml和(86.48±12.75)μIU/ml。结论:依改良后的分离纯化方案分离大鼠胰岛可获得高纯度高活率的胰岛细胞,且细胞形态正常、功能良好。     

胰岛分离、纯化制备的改进

目的 探讨大型哺乳动物胰岛机械化大量分离、纯化的方法,为人类胰岛移植物的大量制备摸索创造条件.方法 应用改进的机械化胰岛分离、纯化系统,用HCA和UW液顺序原位灌洗犬胰腺,主副胰管插管,4℃胶原酶-V(1.5 g/L)+胰酶抑制剂pefabloc(0.4 mmol/L)灌注后,Ricordi-Chamber消化罐消化,4℃COBE2991连续密度梯度离心纯化,测定胰岛当量(IEQ)、胰岛纯度及存活率、胰岛素及C-肽的释放量、培养24 h后光镜及电镜观察.结果 胰腺消化时间为(25.0±6.0)min,胰岛外分泌腺包裹率为(9.4±2.4)%,消化后胰岛收获量为(17.2±3.6)×104IEQ/每个胰腺,纯化后胰岛收获量为(8.3±2.0)×104IEQ/每个胰腺,胰岛纯度为(89.7±3.5)%.纯化胰岛体外低糖与高糖刺激下胰岛索分泌量及C-肽的释放量良好,培养24 h后形态结构及功能正常.结论 本实验室改进的胰岛机械分离方法及各设备运行可靠,获得的胰岛形态功能良好,可望用于临床人类胰岛的大量制备.     

小鼠胰岛的分离与纯化

目的 探讨稳定、高效的小鼠胰岛细胞的分离纯化方法.方法 采用胆总管内灌注不同浓度胶原酶(分别为0.5、1.0、1.5 g/L)消化胰腺的方法分离BALB/C小鼠胰岛,Ficoll-400不连续密度梯度离心法纯化胰岛.双硫腙(DTZ)对胰岛进行特异性染色计算胰岛产量及纯度,葡萄糖刺激释放试验体外测胰岛功能.结果 不同浓度的胶原酶在不同时间内消化胰腺后收获的胰岛数量有较大的差异,其中采用0.5 g/L胶原酶V、38 ℃水浴消化20 min组收获量最大为(230±20)个胰岛细胞团,纯度约为90%.DTZ染色后胰岛呈腥红色,形态完整.葡萄糖刺激释放实验示高糖刺激后胰岛素释放量为低糖刺激后的2.3倍.结论 胶原酶浓度、消化时间和温度是影响小鼠胰岛分离结果的重要因素,当胶原酶浓度为0.5 g/L,消化时间20 min时可获得数量较多,纯度较好的胰岛细胞.

Abstract：

Objective To investigate the stable and efficient method of isolation and purification from mice pancreas. Methods BALB/C mouse islets were isolated by different concentrations of collagenase digestion (0. 5, 1. 0, 1. 5 g/L respectively) and purificated by Ficoll density gradient centrifugation.The number, purity and vitality of the islets were analyzed. The production and purity of the islets were checked by Dithizone immunofluorescence staining. The glucose-induced insulin secretion was detected by enzyme linked immunosorbent assay (ELISA) for islet function in vitro. Results Different number of islets was obtained by mice pancreas digestion with different concentrations of collagenase and for different digestion durations.After the mouse pancreata were digested in 38 C and with 0. 5 g/L collagenase V for 20rmin, maximum number of islets was obtained, and the purity of the final preparation was ＞ 95%. After culture in vitro, insulin release of islets under high glucose stimulation was 2. 3 times of that under low glucose stimulation. Conclusion Concentration of collagenase, temperature, and digestion duration were important factors of islet isolation and purification from mice pancreas. More production and higher purity of islets were obtained under the concentration of 0. 5 g/L collagenase Ⅴ for 20 min.     

大鼠胰岛的分离纯化方法改进与功能鉴定

目的 通过改进胰腺消化和分离的技术条件,提高成年大鼠胰岛分离纯化产率和质量. 方法 用胶原酶Ⅺ液灌注消化成年SD大鼠胰腺,对胰岛分离纯化方法加以改进:以 4 种比重的 Euro- Ficoll (F1∶D=1.132,F2∶D=1.108,F4∶D=1.069) 和 Hank's 液(F5∶D=1.023) 不连续密度梯度离心,以离心半径 15 cm,2 000 r/min 于4℃缓慢升降离心 20 min,收集位于F1 和 F2界面的胰岛.双硫腙特异染色法鉴定胰岛纯度;二醋酸酯荧光素/碘化丙啶染色法计算胰岛成活率;放射免疫分析法检测葡萄糖刺激的胰岛素分泌量,计算刺激指数.将胰岛当量(islets equivalent quantity,IEQ) 为 1000 的胰岛移植于同品系糖尿病大鼠肾包膜下,9d 内隔日观察动物血糖的变化,评价胰岛功能.比较分离条件优化前后收获胰岛的产率和质量. 结果 改进纯化方法后每只大鼠胰岛收获量为(920±122) IEQ,胰岛纯度> 90%,胰岛细胞成活率为 91%±2%.胰岛细胞功能良好,在低糖和高糖刺激后培养液中胰岛素浓度分别为(18.25±0.32) mU/L 和(36.70±3.57)mU/L,刺激指数为 2.01±0.15.1000 IEQ 胰岛移植于糖尿病大鼠肾包膜下,观察期内可维持动物血糖水平正常. 结论 改进后的胶原酶灌注消化和不连续梯度离心方法提高了胰岛的产率,保证了胰岛的高纯度及高成活率.     

小鼠胰岛的分离纯化及体外功能检测的实验研究

目的：探讨获得高质量小鼠胰岛的分离纯化方法，评价其功能。方法：采用胆总管内胶原酶灌注膨胀消化胰腺的方法分离小鼠胰岛，不连续密度梯度离心法纯化胰岛，用双硫腙（Dithizone，DTZ）对胰岛进行特异性染色计算胰岛产量及纯度，以葡萄糖和茶碱刺激胰岛素释放检测胰岛功能。结果：胰岛的产量和活性主要与胰腺均匀膨胀和胶原酶的消化时间有关。平均每个小鼠胰腺能得到150～250个高质量胰岛，活性〉95％，纯度〉90％。葡萄糖及茶碱（carbachol，Cch）刺激后胰岛素释放量明显增加。结论：改良的胆总管内胶原酶灌注膨胀消化小鼠胰腺及不连续密度梯度Ficoll-400纯化胰岛的方法，可获得产量较高、纯度及功能较好的胰岛。     

成年猪胰岛分离和纯化的实验研究

采用经胰导管连续灌注胶原酶技术，从每个胰腺中获得平均４６９１００±２０８３００个胰岛（７６９３个胰岛／ｇ胰腺），纯化后平均１５２０００±１０９０００个胰岛／胰腺（２４８６个胰岛／ｇ胰腺）。平均回收率３２．４９％，纯度８０％。在培养第１、第３和第７天间，胰岛细胞对高糖和茶碱刺激有明显反应，胰岛素释放量，分别为低糖的１．３９～３．６７倍，（Ｐ＜０．０５），提示分离纯化后及培养期间的胰岛功能良好。胰岛形态学观察表明，双硫腙特异性的与胰岛Ｂ细胞胰岛素颗粒内的锌螯合使其着色，台盼兰染色证实胰岛活率在９０％以上。本文将分离纯化后及培养的经双硫腙染色的阳性细胞团进行电镜检查，证实为形态结构完整的胰岛。     

人工生物胰的体外分泌功能研究

目的 探讨海藻酸钠-氯化钡微囊对成人胰岛细胞体外分泌功能的影响.方法 对6例成人胰腺组织称重后采用V型胶原酶消化法分离,采用Ficoll间断密度梯度离心纯化法纯化,采用DTZ染色显微镜下评价胰岛细胞的数量、纯度.采用海藻酸钠氯化钡为材料包裹成人胰岛,体外培养及放射免疫法测定培养液中基础胰岛素浓度.结果 成人胰腺经胶原酶消化分离后,胰岛平均收获量(3600±447)个胰岛/g胰腺；Ficoll间断密度梯度离心纯化后,每克胰腺组织平均收获量(2140±207)个胰岛,纯度大于70％；成人胰岛细胞培养2、4、6d后,微囊化组第2、4、6天的基础胰岛素平均浓度(每100个胰岛单位mU/L)分别为3.302±1.63、3.504±1.10、2.921±1.13,未微囊化组的基础胰岛素平均浓度(每100个胰岛单位mU/L)分别为3.814±1.49、4.175±1.60、3.617±1.34,两组基础胰岛素浓度差异无统计学意义(P＞0.05).结论 人工生物胰具有良好的体外分泌功能,包裹成人胰岛的海藻酸钠-氯化钡微囊对胰岛体外分泌胰岛素的功能无影响.     

不同胶原酶消化对大鼠胰岛的纯化和获得率的影响

目的 比较不同胶原酶消化大鼠胰腺的效果,选择消化效果较好的胶原酶.方法 采用随机数字表法将SD大鼠分为2组,胶原酶P组大鼠胰腺使用1 mg/ml的胶原酶P液进行消化,Ⅴ型胶原酶组大鼠胰腺使用1 mg/ml的Ⅴ型胶原酶进行消化.胰腺消化后,对获得的两组大鼠胰岛进行纯化、培养.采用双硫腙染色于倒置显微镜下计数纯化前后获得的两组全部胰岛数量,并计算胰岛当量(IEQ);采用吖啶橙和碘丙啶双色荧光染色,于荧光显微镜下计数纯化后胰岛的活率;两组大鼠胰岛经纯化、培养2d后进行胰岛素释放试验,观察两组胰岛的功能.结果 纯化前,两组间每个大鼠胰腺获得的胰岛数量的差异无统计学意义(P＞0.05);但两组间IEQ的差异有统计学意义(P＜0.05);经纯化后,Ⅴ型胶原酶组和胶原酶P组每个大鼠胰腺获得的胰岛数量分别为485±113和643±82,IEQ分别为674±157和989±126,两组间胰岛数量和IEQ的比较,差异均有统计学意义(P＜0.05).Ⅴ型胶原酶组和胶原酶P组大鼠胰岛经纯化后,其活率分别为(96.13±1.13)％和(96.38±0.92)％,两组比较,差异无统计学意义(P＞0.05).胰岛素释放试验结果显示,在低糖或高糖刺激下,两组间大鼠胰岛功能的差异均无统计学意义(P＞0.05).结论 两种胶原酶均适用于大鼠胰腺的消化,但胶原酶P消化效果较Ⅴ型胶原酶稳定,且胰岛获得率也较高.     

成人胰岛细胞的分离

目的　探讨成人胰岛细胞的分离及胰腺冷缺血时间与胰岛细胞活率的关系。方法　采取胰、肾联合切取 ,经腹主动脉插管 ,用自制的灌注器以高渗枸橼酸盐嘌呤溶液 (HC A液 ) 15 0 0～2 0 0 0ml进行原位灌洗。将肾与胰腺、十二肠、脾分离 ,采用胶原酶P消化胰腺 ,分离并纯化胰岛细胞 ,以双硫腙及丫腚橙染色 ,测定所得到的胰岛细胞的纯度及活率。结果　胰腺的冷缺血时间为 2 .5～ 8h ,温缺血时间为 0～ 3min。胰岛收获量为 (2 .38± 0 .6 7)× 10 3 IEQ/g ,纯化后胰岛细胞的活率为 19%～ 83% ,冷保存指数 (或输注指数 )为 9.8～ 6 6 .4。胰岛细胞的活率与胰腺的冷缺血时间呈负相关 ,冷保存指数和胰岛细胞活率呈负相关。结论　以高渗枸橼酸盐嘌呤溶液灌洗、胶原酶P消化胰腺所得到的胰岛细胞活率高 ,但胰腺的冷缺血时间不宜超过 5h。     

Serine-protease inhibition during islet isolation increases islet yield from human pancreases with prolonged ischemia.

BACKGROUND: Islet isolation from the pancreatic tissue matrix remains highly variable. Recent evidence suggests that intrinsic human pancreatic proteases, including trypsin, may inhibit effective collagenase enzymatic activity during islet isolation, thereby impairing the isolation success. In this study we have hypothesized that serine protease inhibition applied during pancreatic digestion, could improve yield and/or functional viability of islets isolated from human pancreases. METHODS: Twelve organ donor pancreases with 12.9+/-0.6 hr cold storage (mean+/-SEM) were perfused via their ducts with Liberase-HI enzyme in the presence (n=6) or absence (n=6) of 0.4 mM Pefabloc. All were then gently dissociated and their purified islets separated with Ficoll density gradient centrifugation. RESULTS: Donor-related factors (age, gender, cold storage time, body mass index, and pancreas weight) did not differ significantly between the two experimental groups. Pefabloc supplementation did not affect the digestion time, islets remaining trapped in exocrine tissue, or final islet purity. Islet recovery was increased in the Pefabloc-treated group (mean+/-SEM yield 323.8+/-80.8 x 10(3) islet equivalents vs. 130.8+/-13.6 x 10(3) islet equivalents, P<0.05). Cellular composition, DNA and insulin content, and insulin secretory activity of the isolated islets was similar. CONCLUSIONS: Inhibition of intrinsic protease activity within pancreases after prolonged cold storage improves isolation of viable islets.     

Isolation and Purification of Islet Cells From Adult Pigs

We used in situ perfusion and a multiple-organ harvesting technique to collect islets from adult pig pancreata. The tissues were digested with collagenase P followed by purification in a lympholyte discontinuous gradient using a COBE2991 cell separator. The yield and purity of isolated islets were evaluated with a light microscope after dithizone (DTZ) staining. Islet function was assessed using an in vitro insulin release assay. The results showed that before purification 275,000 ± 20,895 islet equivalents (IEQ) were obtained from 1 digested pancreas. After purification with gradient centrifugation, the islet yield was 230,350 ± 26,679 IEQ/pancreas. Each gram of the purified pancreatic tissues yielded 2710 ± 229 IEQ with an average purity of 50.2 ± 2.0%. The purified islet cells responded to stimulation with high glucose concentrations (16.7 mmol/L), namely, 4.74-fold greater than the insulin secretion with exposure to the basal level of glucose (3.3 mmol/L; P < .001). These results suggested that the established isolation method can be applied to large-scale purification of fully functional islets from pig pancreata.     

Small intestinal submucosa improves islet survival and function in vitro culture

INTRODUCTION: Most centers maintain isolated human islet preparations in tissue culture to improve the safety as well as the practicality of islet transplantation. However, maintaining viability and recovery of islets remains a challenge. Extracellular matrix (ECM) is one of the most important components of the islet microenvironment. Reconstruction of the cell-matrix relationship seems to be necessary to sustain the structure and function of differentiated islets. Small intestinal submucosa (SIS), a natural ECM, is well known to promote wound healing, tissue remodeling, and cell growth. The purpose of this study was to evaluate recovery and function of isolated rat pancreatic islets during in vitro culture with SIS. METHODS: Pancreatic islets isolated from Wistar rats following intraductal collagenase distension, mechanical dissociation, and EuroFicoll purification were cultured in plates coated with multilayer SIS (SIS-treated group) or without (standard cultured group) for 7 or 14 days in an islet culture media of RPMI 1640 (Gibco). The islets from both experimental groups were stained and counted with dithizone. Islet recovery following culture was determined by the ratio of counts after culture to the yield of islets immediately following islet isolation. The viability of the islets was assessed by a glucose challenge test with low glucose (2.7 mmol/L), high glucose (16.7 mmol/L), and high glucose solution supplemented with 50 micromol/L 3-isobutyl-1-methylxanthine solution. The apoptosis of islet cells was measured by relative quantification of histone-complexed DNA fragments by using enzyme-linked immunosorbent assay. RESULTS: After 7 or 14 days of in vitro tissue culture, the recovery in SIS-treated islets group was about double of that cultured in the plates without SIS coating. In the SIS-treated group, there was no significant difference between the short- and the long-term periods of culture (95.8%+/-1.0% vs 90.8%+/-1.5%, P>.05). Following incubation with high glucose (16.7 mmol/L) solution, the insulin secretion in the SIS-treated group showed a greater increase than the control group after 14 days of culture (20.7+/-1.1 mU/L vs 11.8+/-1.1 mU/L, P<.05). When islets were placed in the high glucose solution containing IBMX, the stimulated insulin secretion was more increased in the SIS-treated than in the control group despite the duration of the culture. The calculated stimulation index of SIS-treated group was about two to three times greater than the control group. In addition, the stimulation index of the SIS-treated group remained constant regardless of short-term versus long-term culture (9.5+/-0.2 vs 10.2+/-1.2, P>.05). Much less apoptosis of islet cells occurred in the SIS-treated than in the control group. CONCLUSION: Coculture of isolated rat islets with native sheetlike small intestinal submucosa seemed to build an ECM for islets providing possible biotrophic and growth factors that promote the recovery and subsequent function of islets.     

Evaluation of human islet-specific functional quality cultured on different gas-permeable membranes

The aim of this study was to investigate different gas-permeable membranes for culturing human islets. Dynamic insulin release was used to assess islet functional quality. Islets isolated from cadaveric pancreata (n = 8) using standard isolation methods were stained with dithizone, counted, and cultured on five different commercially available medical-grade membranes reported to have high permeability to O2, CO2, and other gases. Fraction 1 (20,000 islet equivalents [IEQ] purity >70%; viability >85%) was cultured using serum-free medium in nonadherence tissue culture flasks (group I) and custom-made chambers with membranes (group II). Each vessel contained 5000 IEQ at a density of 30 IEQ/cm2 and 69 IEQ/cm2 for groups I and II, respectively. Islets were cultured for 48 to 90 hours at 37 degrees C in 5% CO2. In vitro dynamic insulin response to low glucose (3 mmol/L), high glucose (16.7 mmol/L), and 25 mmol/L KCI was measured. Stimulation indices were calculated by dividing average of initial response over basal insulin release; basal insulin release defined as average of the first seven values. Islets cultured on MG7 (n = 3) showed a higher stimulation index (3.49 +/- 0.37) compared with flasks (2.44 +/- 0.22), indicating better specific functional quality. Islets cultured on other membranes proved to show similar or worse functional quality than those cultured in flasks. In fact, islets cultured on MG6 (n = 2) were not tested owing to complete disintegration. Islet functional quality was improved when cultured on selected biocompatible gas-permeable membranes; however, finding the best membrane requires further investigation before clinical application.     

Rapid purification of islets using magnetic microspheres coated with anti-acinar cell monoclonal antibodies

A simple, rapid method of islet purification is important in large-scale human islet isolation. We have previously identified monoclonal antibodies specific for acinar cells, but not islets, and described an immunologic method of purification by selective lysis of the acinar cells. An attractive alternative to lysis of the acinar cell is depletion by a magnetic immunomicrosphere technique. We report in this study a rapid, reproducible method of rat islet purification utilizing magnetic microspheres coated with acinar-cell-specific monoclonal antibodies. Pancreatic digestion with collagenase followed by depletion of acinar cells with the magnetic immunomicrospheres (MIMS) yields large numbers of intact islets. We compared the islets thus obtained with hand-picked (HP) islets (control) for yield, purity, in vitro insulin secretory capacities, and in vivo functional viability. The islet yield with the MIMS method (n = 35) was 72.7% that obtained with the HP method (n = 6) (378 +/- 8 vs. 519 +/- 31 islets per pancreas). The purity of the MIMS-isolated islets was 84 +/- 1.9%, ranging from 75-95%. Static glucose stimulation showed excellent function (2-3-fold increase of insulin release over basal levels) with no statistical difference in insulin secretion between MIMS and HP islets. Under microscopic examination, both groups revealed a well-preserved structure with healthy endocrine cells. When 1321 +/- 59 MIMS islets were transplanted into streptozotocin-induced diabetic rats (n = 10), normoglycemia (less than 200 mg/dl) was restored in all recipients following transplantation, and 100% of them remained normoglycemic on day 120 postgrafting. In summary, a rapid, consistent, and simple method of isolating viable, purified rat islets is described. The broad interspecies crossreactivity of the McAb suggests that this technique may be generally useful for islet purification in large mammalia, including man.     

Function and viability of human islets encapsulated in alginate sheets: in vitro and in vivo culture

Islet encapsulation offers an immune system barrier for islet transplantation, and encapsulation within an alginate sheetlike structure offers the ability to be retrievable after transplanted. This study aims to show that human islets encapsulated into islet sheets remain functional and viable after 8 weeks in culture or when transplanted into the subcutaneous space of rats. Human islets were isolated from cadaveric organs. Dissociation and purification were done using enzymatic digestion and a continuous Ficoll-UWD gradient. Purified human islets were encapsulated in alginate sheets. Human Islet sheets were either kept in culture, at 37°C and 5% CO₂, or transplanted subcutaneously into Lewis rats. After 1, 2, 4, and 8 weeks, the human islet sheets were retrieved from the rats and assessed. The viability of the sheets was measured using fluorescein diacetate (FDA)/propidium iodide (PI), and function was measured through glucose-stimulated insulin release, in which the sheets were incubated for an hour in low-glucose concentration (2.8 mmol/L) and then high (28 mmol/L), then high (28 mmol/L) plus 3-isobutyl-1-methylxanthine (50 μm). Human islet sheets remained both viable, above 70%, and functional, with a stimulation index (insulin secretion in high glucose divided by insulin secretion in low glucose) above 1.5, over 8 weeks of culture or subcutaneous transplantation. Islet transplantation continues to make advances in the treatment of type 1 diabetes. These preliminary results suggest that encapsulated islets sheets can survive and maintain islet viability and function in vivo, within the subcutaneous region.     

Successful human islet isolation utilizing recombinant collagenase

The enzymatic dissociation of acinar tissue by collagenase is a substantial step in the isolation of pancreatic islets. Although essential collagenase components have been purified, the variability in the activity of different batches limits long-term reproducibility of isolation success. The utilization of purified recombinant proteases would solve this problem. In the present study, pancreases from multiorgan donors were dissociated by means of digestion-filtration using either Liberase HI (n = 51) or a recombinant collagenase blend (n = 25). No significant differences were found regarding islet yield before and after purification, the percent of exocrine-attached islets, and final purity. However, the ratio between islet equivalents and islet numbers indicated a lesser fragmentation in islets isolated with recombinant collagenase (P < 0.01). In contrast, viability was slightly higher in islets isolated with Liberase (92.3 +/- 0.8 vs. 85.6 +/- 2.9%; P < 0.05). Insulin release during static glucose incubation was not different between experimental groups. Islet transplantation into diabetic nude mice resulted in sustained normoglycemia in either group until the graft was removed. These results demonstrated that viable human islets can be isolated using recombinant collagenase. Final optimization of this enzyme blend would offer continuous reproducibility of isolation success.     

Adhesive growth of pancreatic islet cells on a polyglycolic acid fibrous scaffold

BACKGROUND: The use of cultured pancreatic islet cells for diabetes treatment offers several advantages. In theory, cultured cells show greater purity and lower immunogenicity. However, cultured islet cells display a low survival rate in vitro. In the present study we grew islet cells on a polyglycolic acid (PGA) fibrous scaffold to promote cell adhesion, growth, and viability during prolonged culture. METHODS: Islets isolated from Wistar rat pancreata were digested with collagenase and purified by the Ficoll method. Cells were grown in culture with or without PGA scaffolds. Islet cell purity was determined using a dithizone stain; viability and survival rates were determined using an AO-PI stain. The insulin-secretion index was detected using radioimmunodetection and the growth on an adhesive scaffold analyzed using an inverted microscope and scanning electron microscope (SEM). RESULTS: In contrast to the scaffold-free control group, cells cultured on PGA scaffolds exhibited improved morphology, less cell death, and prolonged survival times. Cell viability and survival rates were significantly increased in scaffolded cells when compared to control cells (P < .05). Increased insulin secretion was observed in the culture solution of scaffolded cells following stimulation with low glucose (5.6 mmol/L) versus high glucose (16.7 mmol/L). The secretion indices of the two groups were significantly different (P < .05). Islet cell growth, as observed under SEM, was tightly circumvolute, adhesive, and three-dimensional. CONCLUSIONS: The present results demonstrated that islet cells can successfully grow and survive in culture on a PGA scaffold. These cells exhibited enhanced viability, survival, and insulin secretion.