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Subcutaneous, isogeneic transplantation of duct-ligated pancreas in streptozotocin diabetic mice: relationships between recovery and hormone contents in transplants or host pancreas.

Recovery from diabetes was observed in streptozotocin-treated mice that received subcutaneous, isogeneic transplants of duct-ligated pancreas. Transplants excised from recovered hosts contained both immunoreactive insulin (IRI) and glucagon (IRG), indicating that both A and B cells capable of hormone storage were present. The IRI content in transplants, although only one sixth of that transplanted 6 wk earlier, was still 21/2 times greater than that in the host pancreas and was inversely related to the plasma glucose of the recipient during and after recovery. The IRI content in the transplant added to that in the host pancreas totaled 13% of the IRI found in the normal mouse pancreas, which sufficed for over-all recovery from diabetes but was insufficient to provide normal glucose tolerance and insulin response to a major glucose challenge. The abnormally high content of glucagon noted in the pancreas of hyperglycemic, sham transplanted mice was reduced by one-half in the pancreas of those transplanted mice returning to normal plasma glucose and insulin. Thus, the insulin content of the transplant was important to the recovery of isografted mice, but in addition, and perhaps as a consequence of recovery, there was a slight increase in the insulin storage capacity of the host pancreas and a marked reduction of glucagon compared to the content of these hormones in the pancreas of hyperglycemic, sham transplanted mice.

Animals

Subcutaneous, isogeneic transplantation of either duct-ligated pancreas or isolated islets in streptozotocin diabetic mice.

Recovery from hyperglycemia was observed in streptozotocin diabetic mice that received subcutaneous, isogeneic transplants of either isolated islets or duct-ligated pancreas. Transplants of isolated islets obtained from collagenase-digested adult pancreas provided recovery from hyperglycemia, but the incidence of recovery depended on the amount of islet tissue initially transplanted. Hyperplastic, insulin-rich islets obtained from the pancreas of obese hyperglycemic mice (ob/ob) allowed recovery between 3 and 6 weeks, whereas an equivalent number of islets obtained from non-obese, normal donors gave only partial recovery after 8 weeks. Implantation of pancreatic endocrine tissue obtained from adult donors whose pancreatic ducts were ligated several weeks earlier, led to consistent recovery within 8 to 10 weeks. The content of immunoreactive insulin (IRI) extracted from transplants of mice recovering from hyperglycemia was 16 to 19% of that found in the normal mouse pancreas and was about 4 times greater than that remaining in the recepient's own pancreas. Transplants removed from hosts that did not recover contained a relatively small amount of IRI indicating that these transplants contained insufficient insulin stores to allow recovery form hyperglycemia.

Animals

Islet transplantation in experimental diabetes of the rat. VI. Rate of regression in diabetic kidney lesions after isogeneic islet transplantation: quantitative measurements.

Intraportal transplantation of isogeneic adult islets in diabetic rats resulted in long-lasting amelioration of the metabolic disorder. The effect upon diabetes-induced kidney changes (enlargement of mesangial space, capillary changes, cell-proliferation) was examined quantitatively by morphometric studies. The major effect was a remarkable reduction of the mesangial space and re-widening of the capillary lumina. The number of endothelial cells was lowered. Regarding epithelial and mesangila cells no difference was observed between normal, diabetic and transplanted animals of age-matched groups.

Animals

Isogeneic or allogeneic transplantation of duct-ligated pancreas in streptozotocin diabetic mice.

Recovery from hyperglycaemia was observed in three different mouse hybrids that were made diabetic with streptozotocin, and then transplanted with pancreas from isogeneic donors whose pancreatic ducts were ligated over 8 weeks earlier. Recovery did not occur in recipients of allografts indicating that islets in ligated pancreas cannot be successfully transplanted across a major histocompatibility barrier. However, in lethally irradiated mice injected with allogeneic bone marrow (allogeneic radiation chimeras), subsequent transplantation of ligated pancreas from either isogeneic donors or allogeneic donors of the same strain as the bone marrow donor decreased blood glucose of diabetic recipients. Thus, irradiation and allogeneic bone marrow therapy allow subsequent allogeneic transplantation of functional islet tissue in diabetic mice. Observations on diabetic mice transplanted isogeneically with ligated pancreas suggest that recovery from hyperglycaemia was more consistent when grafts were placed subcutaneously rather than intraperitoneally and when hosts received ligated pancreas from three donors rather than one. Thus, the site and amount of tissue transplanted are important considerations in the transplantation of ligated pancreas. Persistence of endocrine beta-cells in ligated pancreas was required for recovery in grafted mice since diabetic hosts failed to recover when grafted with ligated pancreas obtained from alloxan or streptozotocin-treated, diabetic donors.

Animals

[Tracheal transplantation in inbred strains of rats.--IV. Histologic and histoautoradiographic findings in the epithelium (author's transl)].

In the first ten days after transplantation isogeneic and allogeneic tracheal transplants keep their epithelium, showing metaplasia as a sign of distinct regenerative activity in this time. In various degrees dependent on the constellation of experiments there are only signs of a weak chronic rejection. After more than 280 days again a stratified epithelium can be seen. In exeptional cases mucosa of second-set-transplants only show an obvious rejection reaction.

Animals

A cytokinetic analysis of bacillus calmette-guérin-induced growth control of a murine leukemia.

The cytokinetics of an isogeneic, transplantable, lymphoid leukemia, growing as an ascitic tumor in the C57BL/6 mouse, has been investigated during normal growth and during regression induced by weekly injections i.v. of 1.0 mg Bacillus Calmette-Guérin (BCG). Survival was significantly prolonged in the BCG-treated group, and 27% of the mice were apparently cured. The tumor growth curves showed, furthermore, that BCG-rreated mice could be divided into two groups according to whether the ascitic tumor cell number was at control level or below that of the controls. By methods such as stathmokinetics, tritiated thymidine autoradiography, and cytophotometry, it was demonstrated that the proliferative activity was higher in BCG mice with a low tumor mass as compared to controls and BCG mice with a tumor mass similar to that of controls. The cytokinetic characteristics of BCG mice with a low ascitic tumor cell number were especially expressed by high mitotic activity, high initial labeling indices, short potential tumor doubling time, and a low number of G0-G1 cells. Furthermore the ascitic tumor cell loss rate was increased in these mice during the whole experimental period. It was deduced from the various parameters and especially from the cytophotometric and autoradiographic results that BCG induces a preferential kill of tumor cells in G0-G1 and the first part of the S phase. In addition, the cytological aspects of the ascitic tumor were found to be related to the cell kinetic pattern as the amount of small and large tumor cells increased and decreased, respectively, with accumulation of tumor cells in G0-G1.

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Neonatal islet cell transplantation in the diabetic rat: effect on the renal complications.

PVG/C rats were made diabetic with streptozotocin and after 1 mth received a single intraperitoneal transplant of isogeneic collagenase digested pancreatic tissue. Renal changes have been studied in transplanted and control diabetic rats using light and electron microscopy and immunological techniques. Following transplantation, renal lesions did not increase in severity and progressive basement membrane thickening was prevented. Ultrastructurally many glomeruli showed a significant reduction in the mesangial matrix and the tubular and mesangial cell changes reverted to normal. Immunofluorescent studies demonstrated a similar reduction in the glomerular deposits of IgG. Possibilities for the treatment of diabetes mellitus in human patients are discussed.

Animals

Syngeneic transplantation of fetal rat pancreas. II. Effect of insulin treatment on the growth and differentiation of pancreatic implants fifteen days after transplantation.

Eight 18-days-postcoitum fetal pancreases were transplanted to isogenic alloxan-diabetic male rats. Some recipients were treated with insulin for seven days immediately after transplantation. Eight animals in both the insulin-treated group and control group were killed 15days after transplantation for morphologic and hormonal studies of the transplanted tissue. Using the morphometric technique of linear scanning, the insulin, glucagon, and somatostatin immunocytochemically positive, cell masses of the fetal pancreatic implants were quantitated. The beta cell mass of the implants from the control animals increased roughly eightfold from the time of transplant; insulin treatment resulted in a further two- to threefold increase. The insulin content of the implants increased more than did the beta cell mass, resulting in the fivefold increase in insulin per beta cell. The alpha cell and delta cell masses did not change during the transplant site, the mass of functional beta cells, and the cell-to-cell content of the implanted tissue. These results are discussed in relation to previous quantitative studies of pancreatic islet cell growth. The relationships of the transplant site, the mass of functional beta cell, and the cell-to-cell interaction within the islet to the maintenance of glucose homeostasis are also discussed.

Animals

Bone marrow transplantation after lethal chemotherapy in "nude" mice.

Isogenic bone marrow transplantation was performed in "nude" and normal C3H mice after lethal doses of dimethylmyleran (DMM), meso-DMM, and (+/-) DMM were given. Nude mice were not more sensitive to DMM or its isomers than normal mice. With adequate cell doses in the range of 3 X 10(6) to 30 X 10(6) bone marrow cells or 10 X 10(6) to 30 X 10(6) spleen cels, the survival rate after lethal chemotherapy was not significantly different between nude mice reconstituted with a graft from nude donors and normal mice reconstituted with a graft from normal donors. Only with suboptimal cell dose (1 X 10(6) bone marrow cells) was survival superior in normal mice. Thinsic factor. Nude mice accepted also bone marrow grafts from allogeneic nude donors.

Animals

The fate of intraportally transplanted islets in diabetic rats. A morphologic and immunohistochemical study.

Streptozotocin-induced diabetes in the rat can be reversed by the transplantation of isogenic islets of Langerhans from neonatal donors. We studied the morphology of intraportally transplanted islets with the aid of the immunoperoxidase staining technique to identify insulin-, glucagon-, somatostatin-, and pancreatic polypeptide-containing cells at 24 hours, 48 hours, 1 week, 2 weeks, 4 weeks, 39 weeks, and 65 weeks after transplant. Embolized pancreatic tissue, composed of approximately 80% acini and 20% islets, is initially distributed throughout the liver mainly to terminal branches of the portal system. Endothelialization and organization occur rapidly with the smaller fragments and within the first 4 weeks for larger thrombi. Exocrine pancreatic elements largely disappear as islet cells move into the hepatic lobules from the portal spaces. At 65 weeks after transplant, all islet cell types can be identified within large complex islet structures. The results of this study establish the survival and continued function of all known rat pancreatic islet cell types long after transplantation and support the theory that islet transplantation may represent the most physiologic replacement of hormonal deficiencies in the diabetic recipient.

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Cytomegalovirus infection in guinea pigs. III. Persistent viruria, blood transmission, and viral interference.

Chronic persistent infection with cytomegalovirus (CMV) was studied in random-bred Hartley and inbred strain 2 guinea pigs. Infectious virus was isolated from the urine, kidney, spleen, pancreas, salivary gland, and cervix, but not from buffy coat of persistently infected guinea pigs. Strain 2 animals developed a high rate of chronic viruria, which was not related to isolation of CMV from renal tissue. In female strain 2 guinea pigs viruria was more than twice as prevalent as in males (56% vs. 24%). Transfusion of buffy coat from persistently infected strain 2 animals resulted in CMV infection in both isogenic and allogenic blood recipients, but buffy coat from uninfected donors did not activate CMV in persistently infected isogenic and allogenic blood recipients. Experimental CMV infection of young strain 2 guinea pigs interfered with the expression of guinea pig herpes-like virus, a common endogenous virus in strain 2 animals.

Animals

Dose-dependence of the augmentation of hemopoiesis by thymocytes.

We have used the spleen colony assay and the 24-h uptake of 59Fe by hemopoietic tissues to study certain quantitative aspects of the interaction of parent-strain thymocytes and marrow cells transplanted into lethally irradiated F1 hybrid mice. The data show that thymocytes augment bone marrow growth at least partly by increasing the proportion of stem cells from parental marrow that from colonies in the hybrid animal. This increase in spleen colony number is a linear function of the number of thymocytes injected within certain dose ranges. At higher thymocytes doses, a plateau is reached where further increase in the number of thymocytes injected does not result in an increase in the number of spleen colonies; this plateau occurs at just that level of response given by the same marrow dose when transplanted into isogeneic (parent-strain) recipients. Experiments in which 59Fe uptake up red blood cells and spleen was used to measure marrow growth yielded similar results, except that the plateau in uptake occurred at a much lower level than that measured for the same marrow dose in isogeneic recipients. This apparent discrepancy in results obtained from the two different assays may best be explained by the recent observation that thymocytes shift the differentiation pattern of marrow stem cells away from erythropoiesis and toward granulopoiesis. The absolute thymocyte dose seems to be more important than the thymocyte: marrow-cell ratio in determining the degree of augmentation observed.

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Effects of pre-irradiation on isogeneic and semi-isogeneic CFU growth: a study on genetic resistance.

The genetic resistance to a parental bone marrow transplant as demonstrated, when transplantation was performed early after irradiation, failed to occur if the interval between irradiation and transplantation was increased to 4 days. A similar radiation induced weakening of genetic resistance to a parental bone marrow graft in spleen and bone marrow could be demonstrated in mice, which had been irradiated with a sublethal dose at 7 days prior to the lethal irradiation and transplantation. The pre-irradiation of the recipient with a sublethal dose induced an enhancement of the growth in spleen and bone marrow of isogeneic transplanted CFU. The pre-irradiation of a single tibia also resulted in a significant weakening of the resistance in the spleen. The experiments with partial body pre-irradiation suggested a local effect of the pre-irradiation, but it could be shown that the enhanced CFU growth is not caused by an enhanced seeding of CFU in pre-irradiated bone marrow. The role of microenvironment in the phenomenon of genetic resistance is discussed.

Animals

Intrahepatic transplantation of pancreatic islets in the rat.

Islets of Langerhans from isogeneic donor rats were transplanted directly into the hepatic parenchyma of recipients which had been made severely diabetic by streptozotocin (glycaemia ranging between 400 and 1090 mg%). Complete control lasting up to 13 months was achieved in 65% of recipients by using 600-800 islets. Following intravenous glucose administration, each rat responded similarly to normal rats with a rapid but reduced release of insulin. Cytoimmunofluorescence and electron microscopic studies demonstrated the presence of both functional insulin and glucagon cells, within the transplanted islets. It is suggested that for various reasons direct intrahepatic transplantation might become the preferred method for islets.

Animals