O transplante de ilhotas microencapsuladas constitui uma alternativa terapêutica interessante para o Diabetes Mellitus tipo 1, permitindo um melhor controle glicêmico e eliminando a necessidade de imunossupressão. Entretanto, a manutenção a longo prazo da viabilidade das células-&#946; ainda é um desafio. No isolamento, a perda da matriz extracelular e as condições hipóxicas subsequentes afetam decisivamente a sobrevivência e funcionalidade das ilhotas. Objetivo Para diminuir o estresse sobre o enxerto, levando a um sucesso prolongado do transplante, propôs-se a adição de perfluorocarbono (PFC) ou laminina (LN), moléculas associadas respectivamente à oxigenação e interações célula-célula, ao biomaterial baseado em alginato, Biodritina, adequado ao encapsulamento celular. Metodologia Para testar a estabilidade das formulações PFC-Biodritina e LN-Biodritina, microcápsulas foram submetidas a diferentes estresses (rotacional, osmótico, temperatura e cultura) por 7 e 30 dias. A pureza do biomaterial foi avaliada pela coincubação com macrófagos murinos RAW264.7, por 3, 9 e 24h, quando a ativação dos macrófagos foi observada pela expressão gênica de IL- 1&#946; e TNF&#945;. Microcápsulas implantadas i.p. em camundongos foram recuperadas após 7 ou 30 dias, para análises de biocompatibilidade. A expressão de níveis de mRNA (bax, bad, bcl-2, bcl-XL, xiap, caspase 3, mcp1/ccl2, hsp70, ldh, insulina 1 e 2), proteínas (Bax, Bcl-XL e Xiap) e a atividade de Caspase3 foram avaliadas em ilhotas microencapsuladas com PFC- e LN-Biodritina, após cultura de 48h em condições de normóxia e hipóxia (<2% O2). Camundongos diabéticos foram transplantados com ilhotas encapsuladas nas diferentes formulações e os animais foram monitorados pelas variações de massa corporal, glicêmicas e pela funcionalidade do enxerto (TOTGs). As ilhotas foram recuperadas de animais normo ou hiperglicêmicos e uma análise de biocompatibilidade das cápsulas foi realizada, assim como a avaliação funcional das células-&#946;. Após o explante, a glicemia dos animais normoglicêmicos foi monitorada para se atestar a eficiência das ilhotas transplantadas. Resultados Microcápsulas de PFC- e LN-Biodritina são tão estáveis e biocompatíveis quanto as de Biodritina. Para ilhotas encapsuladas em ambos os materiais, em normóxia ou hipóxia, observou-se uma modulação gênica que sugere proteção contra apoptose. Adicionalmente, encontrou-se uma diminuição na expressão de genes indicadores de estresse (mcp1, hsp70). Uma diminuição nos níveis de mRNA de ldh foi vista para PFC-Biodritina, mas o oposto foi encontrado para LN-Biodritina. As diferenças encontradas na expressão proteica sugerem o mesmo padrão anti-apoptótico. Caspase3 não foi modulada por nenhum biomaterial. Nos experimentos de transplante, apenas LN-Biodritina levou reversão prolongada do diabetes, com 60% dos animais normoglicêmicos, 198 dias pós-cirurgia, comparado a 9% do grupo Biodritina. O TOTG demonstrou que camundongos transplantados com ilhotas encapsuladas secretaram mais insulina do que controles, 60 (LN-Biodritina) ou 100 (PFC- e LN-Biodritina) dias pós-cirurgia. O explante restabeleceu a hiperglicemia nos camundongos. Microcápsulas recuperadas de animais hiperglicêmicos apresentavam uma extensa adesão celular. Testes de secreção de insulina in vitro demonstraram que somente ilhotas do grupo normoglicêmico responderam às variações da concentração de glicose. Conclusão A adição de moléculas bioativas à Biodritina é capaz de diminuir o estresse em ilhotas isoladas e tem o potencial de melhorar a terapia pelo transplante de ilhotas. / Transplantation of microencapsulated islets represents an attractive therapeutical approach to treat type 1 Diabetes Mellitus, accounting for an improved glycemic control and the abolishment of immunosuppressive therapies. However, maintenance of long-term &#946;-cell viability remains a major problem. During islet isolation, the loss of extracellular matrix interactions and the hypoxic conditions thereafter dramatically affect &#946;-cell survival and function. Objective To lessen the burden of islet stress and achieve a better outcome in islet transplantation we tested the addition of perfluorocarbon (PFC) or laminin (LN), molecules associated respectively with oxygenation and cell-cell interaction, to Biodritin, an alginate-based material suitable for cell microencapsulation. Methodology To test the stability of PFC-Biodritin and LN-Biodritin composites, microcapsules were subjected to different stresses (rotational, osmotic, temperature and culture) for 7 and 30 days. To assess biomaterial purity microcapsules were co-incubated with RAW264.7 murine macrophage cell line for 3, 9 and 24h and macrophage activation was detected through mRNA levels of IL-1&#946; and TNF&#945;. Microcapsules were implanted i.p. in mice and retrieved after 7 or 30 days, for biocompatibility analyses. Gene expression at mRNA (bax, bad, bcl-2, bcl-XL, xiap, caspase 3, mcp1/ccl2, hsp70, ldh, insulin 1 and 2) and protein (Bax, Bcl-XL and Xiap) levels, together with Caspase3 activity, were evaluated in islets microencapsulated in PFC- or LN-Biodritin, upon culturing for 48h in normoxic or hypoxic (<2% O2) conditions. Diabetic mice were transplanted with PFC- or LN-Biodritin microencapsulated islets, followed by assessments of body weight, glycemia and graft function by oral glucose tolerance tests (OGTTs). Microencapsulated islets were retrieved from normoglycemic or hyperglycemic mice and biocompatibility analyses of the beads together with a functional assessment of the graft followed. After graft removal, normoglycemic animals had their glycemias monitored to attest the efficacy of the transplanted islets. Results PFC- and LN-Biodritin microcapsules were as stable and biocompatible as Biodritin. For both biomaterials in normoxia and hypoxia a modulation in gene expression was observed in islets associated with a protection against apoptosis. Also, a decreased expression of stress-related genes (mcp1, hsp70) was evidenced. ldh mRNA levels were down-regulated in PFC-Biodritin microencapsulated islets but upregulated in the presence of LN. Increased levels of insulin mRNA were observed. The differences seen in protein expression indicated the same anti-apoptotic pattern. Caspase3 activity was not different between groups. Concerning diabetes reversal experiments, only mice transplanted with LN-Biodritin microencapsulated islets presented a better outcome, with 60% remaining euglycemic at 198 days post-surgery, compared with 9% for the Biodritin group. OGTT showed that mice transplanted with encapsulated islets secreted more insulin than normal mice, 60 (LN-Biodritin) or 100 days (PFC- and LN-Biodritina) posttransplant. Hyperglycemia was achieved after the retrieval of microcapsules showing graft efficacy. Retrieved microcapsules revealed an extensive overgrowth in most beads from hyperglycemic mice. A static glucose stimulated insulin secretion test revealed that only islets from normoglycemic subjects were able to secrete insulin according to glucose concentration. Conclusion- The addition of bioactive molecules to Biodritin may lessen the stress of isolated islets and have the potential to improve islet transplantation therapy.

O transplante de ilhotas pancreáticas humanas é considerado uma estratégia promissora para curar pacientes portadores de Diabetes Mellitus tipo 1. Entretanto, sua eficiência é dramaticamente afetada pelo rendimento das ilhotas no processo de isolamento/purificação e pela viabilidade das células após o transplante. As ilhotas pancreáticas isoladas são obtidas através da perfusão do pâncreas com colagenase e purificação em gradiente de densidade. As espécies reativas de oxigênio (ERO) exercem um papel importante durante a obtenção e o transplante de ilhotas pancreáticas humanas, contribuindo significativamente para diminuir a viabilidade dessas células. Nesse trabalho foram avaliadas as respostas oxidativas de ilhotas pancreáticas humanas durante os processos de isolamento/purificação e cultivo. As atividades da superóxido dismutase (SOD), da catalase, bem como os níveis de oxidação em proteínas mostraram-se, na maioria dos casos, aumentados, principalmente durante a etapa de purificação das ilhotas em gradiente de Ficoll e no período de cultura das ilhotas. Esses resultados indicam que a purificação em gradiente de Ficoll parece ser uma etapa crítica de geração das ERO, assim como longos períodos de cultivo. Porém, verificou-se que influências advindas dos diferentes doadores (idade, causa- mortis, estilo de vida, etc.) e condições de preservação do órgão (tempo de isquemia, solução de conservação, etc.) poderiam estar relacionadas à discrepância de alguns resultados encontrados. Com o intuito de minimizar tais variáveis, optou-se por estudar os efeitos relacionados ao Ficoll em células de insulinoma INS-1E, um modelo celular fisiologicamente semelhante. Para tanto, as atividades das enzimas antioxidantes SOD, catalase, glutationa peroxidase (GPx) e glutationa redutase (GR), assim como os danos oxidativos em proteínas e lipídeos, os níveis de glutationa reduzida (GSH) e de glutationa oxidada (GSSG), a viabilidade celular e os níveis de algumas enzimas envolvidas no processo apoptótico como p38, JNK-1, ERK 1-2 e PI3-K expostas a polissacarose (1100 mg/mL), um genérico do Ficoll, foram determinadas. De acordo com os resultados, as atividades da SOD, catalase e GPx presentes em amostras expostas a polissacarose mostraram-se aumentadas. Em cultura, a atividade de isoforma mitocondrial da SOD (Mn-SOD) de células INS-1E correspondeu a 50% da atividade total da SOD. Na presença da polissacarose, a atividade da Mn-SOD aumentou para 80% do total. Além disso, a oxidação de lipídios e de proteínas aumentou e os níveis de GSH e GR diminuíram discretamente. Estes resultados mostraram que a exposição dessas células a polissacarose está associada com o estresse oxidativo. Entretanto, tal exposição não foi responsável pela diminuição da viabilidade celular embora os níveis protéicos de JNK-1, ERK1-2 e PI3-K tenham se mostrado consideravelmente aumentados e os níveis de p38, diminuídos. Os níveis de expressão e a atividade de enzimas antioxidantes são conhecidamente baixos em ilhotas pancreáticas. A N-acetilcisteína (NAC) foi adicionada em cultura de células para prevenir o estresse oxidativo. Nessas condições, a NAC foi capaz de proteger as células INS-1E do estresse oxidativo induzido. Esses resultados sugerem que a exposição à polissacarose está associdada ao estresse oxidativo em células INS-1E e que a NAC foi capaz de prevenir a morte celular de células INS-1E expostas a ERO através do aumento intracelular de GSH. / Human pancreatic islet transplantation is considered a promising strategy to cure the cure Diabetes Mellitus type I. However, transplantation efficiency is dramatically affected by sub-optimum islet recovery in the isolation/purification procedure and islet viability after transplantation. Isolated pancreatic islets are obtained through collagenase perfusion and cell purification in a Ficoll gradient. Reactive oxygen species (ROS) play an important role during human pancreatic islet isolation and may contribute to the decrease in cell viability. The aim of this study was evaluated the response of human pancreatic islets during its isolation/purification and culture time. Activities of superoxide dismutase (SOD) and catalase as well as protein oxidation levels increased in most of analyzed samples, mainly during the Ficoll gradient islet purification step and further culture. Ficoll seems to be the critical step for ROS generation. Nevertheless, it was observed that donors characteristics (aging, cause of death, habits, etc.) and organ preservation conditions (ischemic time, preservation solution, etc.) may be related to our results. To minimize these variations, a physiological cellular model based on INS-1E cells was chosen. The antioxidant enzymes SOD, catalase, glutathione peroxidase (GPx) and glutathione reductase (GR) activities as well the oxidative damage to proteins and lipids, reduced glutathione (GSH) and oxidized glutathione (GSSG) levels, cellular viability and the protein levels of some enzymes responsible for apoptotic signaling like p38, JNK-1, ERK 1-2 and PI3-K upon exposure to polysucrose (1100 mg/mL), a similar of Ficoll, were determined. The SOD, catalase and GPx in samples exposed to polysucrose displayed hight activities. In all cultures, the activity of mitochondrial isoform of SOD (Mn-SOD) corresponds to 50% of total SOD activity. In the presence of polysucrose, the activity of Mn-SOD increased up to 80%. Lipids and protein oxidation levels were also increased and the GSH levels with the GR activity decreased. These results indicated that the exposure of INS-1E cells to polysucrose is associated with oxidative stress. However, the polysucrose exposure was not responsible for cell death although JNK-1, ERK1-2 and PI3-K levels showed hight levels but not p38, upon polysucrose exposure. The expression and activities of antioxidants enzymes are known to be very low in pancreatic islets. N-acetylcysteine (NAC) was added to the INS-1E cultures to prevent oxidative stress. Under these conditions, NAC was able to protect INS- 1E cells from induced oxidative damage by increasing intracellular GSH levels. Taken together, these results suggest that the exposure to polysucrose is related to the oxidative stress in INS-1E cells and NAC seems to be able to maintain cell viability.

<p><strong>Aim: </strong>To investigate the quality of life and the social life situation, with special focus on the consequenses of fear of hypoglycemia (FoH), in Islet transplanted patients.</p><p><strong>Method: </strong>11 patients were included, four women and seven men, who have been Islet tranplanted at Uppsala University Hospital during the years 2001-2009. Two questionaires, Short Form 36 (SF-36) and the Swedish version Hypoglycemia Fear Survey (Swe-HFS) were used to investigate the quality of life, in relation to fear of hypoglycemia. Also, telephone interviews were conducted to investigate the patients social life situation in relation to FoH, after Islet transplantation and were analysed using content analysis method.</p><p><strong>Results:</strong> The mean value for quality of life was lower than that in the normal population. Three out of ten patients experienced FoH. Three predominant themes were revealed, one theme associated with pre- transplant, was “Struggle for control of Social Life Situation” and two themes associated with post-transplant, were “Regain power and controll of  Social Life Situation” and “At Peace with the balance between the Present and the Future”.</p><p><strong>Conclusion:</strong> The patients experienced improved control over social life situation and quality of life in relation to FoH may been improved following islet tranplantation.</p> / <p><strong>Syfte: </strong>Att undersöka ö-cellstransplanterade patienters livskvalitet och sociala livssituation med speciellt fokus på oro/rädsla för hypoglykemi.</p><p><strong>Metod</strong>: I studien inkluderades 11 patienter, fyra kvinnor och sju män, vilka genomgått ö-cellstransplantation vid Akademiska Sjukhuset i Uppsala under perioden 2001-2009. Två frågeformulär, Short Form 36 (SF-36) och den svenska versionen av Hypoglycemia Fear Survey (Swe-HFS) användes för att undersöka patienternas livskvalitet relaterat till oro/rädsla för hypoglykemi. Telefonintervjuer genomfördes för att undersöka patienternas sociala livssituation efter genomgången ö-cellstransplantation relaterat till oro/rädsla för hypoglykemi och analyserats med innehållsanalys.</p><p><strong>Resultat: </strong>Medelvärdet för hälsorelaterad livskvalitet var lägre jämfört med normalbefolkningen och tre av tio deltagare upplevde oro/rädsla för hypoglykemi. Tre övergripande teman med koppling till social livssituation identifierades, ett tema före genomgången ö-cellstransplantation, var ”Kampen om kontroll över social livssituation”, och två teman efter genomförd transplantation, var ”Återtagande av makt och kontroll över social livssituation” samt ”Tillfreds med balans mellan nuet och framtiden”.<strong></strong></p><p><strong>Konklusion: </strong>Patienterna upplevde att kontrollen över den sociala livssituationen och livskvalitet i relation till oro/rädsla för hypoglykemi förbättrades efter genomgången ö-cellstransplantation.</p>

<p>The blood vessels of the pancreatic islets are of crucial importance for oxygen and metabolite supply as well as dispersal of secreted hormones. In addition to this, endothelial cells have an important role in the revascularization process after islet transplantation. Previous studies have reported signs of poor engraftment of transplanted islets, presumably due to impaired revascularization. The aims of this thesis were to investigate the revascularization process of transplanted islets and to examine the role of islet endothelial cells. In this context, the lectin Bandeiraea simplicifolia was found to stain endothelium of both endogenous and transplanted pancreatic islets. By using this lectin we investigated the vascular density of both endogenous and islets transplanted syngeneically beneath the renal capsule, into the spleen or intraportally into the liver of normoglycemic C57BL/6 mice. One month post-transplantation, a time point when the grafts are assumed to be completely revascularized, the vascular density was decreased at all three implantation sites when compared to endogenous islets. Furthermore, most of the blood vessels were located in the graft connective tissue stroma. Similar results were obtained when islet transplant vascular density was determined six months post-transplantation and in cured diabetic animals after one month. In order to evaluate the function of intraportally transplanted islets, we developed a method to retrieve such islets. We treated the implantation organ (liver) first enzymatically (collagenase) and then mechanically, thereafter we could re-isolate the transplanted islets for further in vitro studies. The retrieved islets had a decreased insulin relase, insulin content and glucose oxidation rate when compared to non-transplanted control islets. To understand the role of islet endothelium in the revascularization of transplanted islets we performed angiogenesis GEArray studies on islet endothelial cells, from non-cultured, cultured and transplanted islets. We found that the islet endothelium expressed mRNA for both inhibitors and inducers of angiogenesis, and that this expression differed with time. The functional consequences of this remain to be determined. In summary, the results presented above provide a useful platform for future studies of the morphology and function of islet endothelial cells, especially with a view for elucidating changes induced by islet transplantation.</p>

<p>Transplanting pancreatic islets into the liver through the portal vein is currently the most common procedure in clinical islet transplantations for treating patients with brittle type 1 diabetes. However, most islet grafts fail within a 5-year period necessitating retransplantation. The vascular connections are disrupted at islet isolation and implanted islets depend on diffusion of oxygen and nutrients in the immediate posttransplantation period. Rapid and efficient revascularization is of utmost importance for the survival and long-term function of transplanted islets. </p><p>In this thesis, the influence of the implantation microenvironment for islet engraftment and function was studied. Islets were transplanted into the liver, the renal subcapsular site or the pancreas. Islets implanted into the liver contained fewer glucagon-positive cells than islets implanted to the kidney and endogenous islets. Intraportally transplanted islets responded with insulin and glucagon release to secretagogues, but only when stimulated through the hepatic artery. Thus, the intrahepatic grafts were selectively revascularized from the hepatic artery. The vascular density in human islets transplanted into the liver of athymic mice was markedly lower when compared to human islets grafted to the kidney. Islets implanted into their physiological environment, the pancreas, were markedly better revascularized. Insulin content, glucose-stimulated insulin release, (pro)insulin biosynthesis and glucose oxidation rate were markedly decreased in transplanted islets retrieved from the liver, both when compared to endogenous and transplanted islets retrieved from the pancreas. Only minor changes in metabolic functions were observed in islets implanted into the pancreas when compared to endogenous islets. </p><p>The present findings demonstrate that the microenvironment has a major impact on the engraftment of transplanted islets. Elucidating the beneficial factors that promote engraftment would improve the survival and long-term function of transplanted islets. Ultimately, islet transplantation may be provided to an increased number of patients with type 1 diabetes.</p>

The blood vessels of the pancreatic islets are of crucial importance for oxygen and metabolite supply as well as dispersal of secreted hormones. In addition to this, endothelial cells have an important role in the revascularization process after islet transplantation. Previous studies have reported signs of poor engraftment of transplanted islets, presumably due to impaired revascularization. The aims of this thesis were to investigate the revascularization process of transplanted islets and to examine the role of islet endothelial cells. In this context, the lectin Bandeiraea simplicifolia was found to stain endothelium of both endogenous and transplanted pancreatic islets. By using this lectin we investigated the vascular density of both endogenous and islets transplanted syngeneically beneath the renal capsule, into the spleen or intraportally into the liver of normoglycemic C57BL/6 mice. One month post-transplantation, a time point when the grafts are assumed to be completely revascularized, the vascular density was decreased at all three implantation sites when compared to endogenous islets. Furthermore, most of the blood vessels were located in the graft connective tissue stroma. Similar results were obtained when islet transplant vascular density was determined six months post-transplantation and in cured diabetic animals after one month. In order to evaluate the function of intraportally transplanted islets, we developed a method to retrieve such islets. We treated the implantation organ (liver) first enzymatically (collagenase) and then mechanically, thereafter we could re-isolate the transplanted islets for further in vitro studies. The retrieved islets had a decreased insulin relase, insulin content and glucose oxidation rate when compared to non-transplanted control islets. To understand the role of islet endothelium in the revascularization of transplanted islets we performed angiogenesis GEArray studies on islet endothelial cells, from non-cultured, cultured and transplanted islets. We found that the islet endothelium expressed mRNA for both inhibitors and inducers of angiogenesis, and that this expression differed with time. The functional consequences of this remain to be determined. In summary, the results presented above provide a useful platform for future studies of the morphology and function of islet endothelial cells, especially with a view for elucidating changes induced by islet transplantation.

Transplanting pancreatic islets into the liver through the portal vein is currently the most common procedure in clinical islet transplantations for treating patients with brittle type 1 diabetes. However, most islet grafts fail within a 5-year period necessitating retransplantation. The vascular connections are disrupted at islet isolation and implanted islets depend on diffusion of oxygen and nutrients in the immediate posttransplantation period. Rapid and efficient revascularization is of utmost importance for the survival and long-term function of transplanted islets. In this thesis, the influence of the implantation microenvironment for islet engraftment and function was studied. Islets were transplanted into the liver, the renal subcapsular site or the pancreas. Islets implanted into the liver contained fewer glucagon-positive cells than islets implanted to the kidney and endogenous islets. Intraportally transplanted islets responded with insulin and glucagon release to secretagogues, but only when stimulated through the hepatic artery. Thus, the intrahepatic grafts were selectively revascularized from the hepatic artery. The vascular density in human islets transplanted into the liver of athymic mice was markedly lower when compared to human islets grafted to the kidney. Islets implanted into their physiological environment, the pancreas, were markedly better revascularized. Insulin content, glucose-stimulated insulin release, (pro)insulin biosynthesis and glucose oxidation rate were markedly decreased in transplanted islets retrieved from the liver, both when compared to endogenous and transplanted islets retrieved from the pancreas. Only minor changes in metabolic functions were observed in islets implanted into the pancreas when compared to endogenous islets. The present findings demonstrate that the microenvironment has a major impact on the engraftment of transplanted islets. Elucidating the beneficial factors that promote engraftment would improve the survival and long-term function of transplanted islets. Ultimately, islet transplantation may be provided to an increased number of patients with type 1 diabetes.

Type 1 diabetes (T1D) is a chronic autoimmune disease targeted against the pancreatic β-cells. Proinflammatory cytokines are considered to play a major role in the destruction of the insulin-producing β-cells. This thesis studied strategies to counteract proinflammatory cytokines in experimental T1D. Both animal models for T1D as well as β-cell preparations exposed in vitro to putative noxious conditions were examined. In the first study we observed that cytokine treatment of mouse pancreatic islets lacking inducible nitric oxide synthase (iNOS) induced a prolongation of the early stimulatory phase of glucose stimulated insulin secretion. Various experiments led to the conclusion that this prolonged stimulatory effect may involve the DAG/PLD/PKC pathway. Next, we transplanted mouse islets deficient in iNOS to spontaneously diabetic NOD mice. We observed a normalization of hyperglycemia but not a delayed allograft rejection compared to transplanted wild type islets. Thus, absence of iNOS in the graft was not sufficient to prolong allograft survival. In paper III we found that sustained glucose stimulation of rat pancreatic islets was coupled to a decreased conversion of proinsulin to insulin. Islet treatment with IL-1β was also coupled to a decreased proinsulin conversion. Islet proconvertase activity may be a target in islet damage. In paper IV prolactin (PRL) was administered to mice in the multiple low dose streptozotocin model and we observed that PRL enhanced a Th2 response. This may contribute to the protective action by PRL in this model of autoimmune T1D. Finally, by examining β-cells overexpressing Suppressor of cytokine signalling 3 (SOCS-3) it was found that this could inhibit IL-1β induced signalling through the NF-κB and MAPK pathways. SOCS-3 overexpression also inhibited apoptosis induced by cytokines in primary β-cells. Lastly, we demonstrated that SOCS-3 transgenic islets were protected in an allogeneic transplantation model.

Aim: To investigate the quality of life and the social life situation, with special focus on the consequenses of fear of hypoglycemia (FoH), in Islet transplanted patients. Method: 11 patients were included, four women and seven men, who have been Islet tranplanted at Uppsala University Hospital during the years 2001-2009. Two questionaires, Short Form 36 (SF-36) and the Swedish version Hypoglycemia Fear Survey (Swe-HFS) were used to investigate the quality of life, in relation to fear of hypoglycemia. Also, telephone interviews were conducted to investigate the patients social life situation in relation to FoH, after Islet transplantation and were analysed using content analysis method. Results: The mean value for quality of life was lower than that in the normal population. Three out of ten patients experienced FoH. Three predominant themes were revealed, one theme associated with pre- transplant, was “Struggle for control of Social Life Situation” and two themes associated with post-transplant, were “Regain power and controll of  Social Life Situation” and “At Peace with the balance between the Present and the Future”. Conclusion: The patients experienced improved control over social life situation and quality of life in relation to FoH may been improved following islet tranplantation. / Syfte: Att undersöka ö-cellstransplanterade patienters livskvalitet och sociala livssituation med speciellt fokus på oro/rädsla för hypoglykemi. Metod: I studien inkluderades 11 patienter, fyra kvinnor och sju män, vilka genomgått ö-cellstransplantation vid Akademiska Sjukhuset i Uppsala under perioden 2001-2009. Två frågeformulär, Short Form 36 (SF-36) och den svenska versionen av Hypoglycemia Fear Survey (Swe-HFS) användes för att undersöka patienternas livskvalitet relaterat till oro/rädsla för hypoglykemi. Telefonintervjuer genomfördes för att undersöka patienternas sociala livssituation efter genomgången ö-cellstransplantation relaterat till oro/rädsla för hypoglykemi och analyserats med innehållsanalys. Resultat: Medelvärdet för hälsorelaterad livskvalitet var lägre jämfört med normalbefolkningen och tre av tio deltagare upplevde oro/rädsla för hypoglykemi. Tre övergripande teman med koppling till social livssituation identifierades, ett tema före genomgången ö-cellstransplantation, var ”Kampen om kontroll över social livssituation”, och två teman efter genomförd transplantation, var ”Återtagande av makt och kontroll över social livssituation” samt ”Tillfreds med balans mellan nuet och framtiden”. Konklusion: Patienterna upplevde att kontrollen över den sociala livssituationen och livskvalitet i relation till oro/rädsla för hypoglykemi förbättrades efter genomgången ö-cellstransplantation.

Islet transplantation has emerged as a promising cell-based therapy for the treatment of diabetes, but its clinical efficacy remains limited by deleterious host responses that underlie islet destruction. In this dissertation, we describe the assembly of cell surface-supported thin films that confer molecular-level control over the composition and biophysicochemical properties of the islet surface with implications for improving islet engraftment. Specifically, the process of layer-by-layer (LbL) polymer self assembly was employed to generate nanothin films of diverse architecture with tunable properties directly on the extracellular surface of individual islets. Importantly, these studies are the first to report in vivo survival and function of nanoencapsulated cells, and have helped establish a conceptual framework for translating the diverse applications of LbL films to cellular interfaces. Additionally, through proper design of film constituents, coatings displaying ligands and bioorthogonally reactive handles may be generated, providing a modular strategy for incorporating exogenously derived regulators of host responses alongside native constituents of the islet surface. Towards this end, a strategy was developed to tether thrombomodulin to the islet surface in a site-specific manner, thereby facilitating local generation of the powerful anti-inflammatory agent, activated protein C. Collectively, this work offers novel biomolecular strategies for cell surface engineering with broad biomedical and biotechnological applications in cell-based therapeutics and beyond.