Transplant Survival Time Research Articles

Soluble donor MHC class I gene transfer to thymus promotes allograft survival in a high-responder heart transplant model.

Thymic selection of self and non-self-reactive lymphocytes is a process that may be targeted to induce donor-specific immunologic unresponsiveness in organ transplantation. In the present study, gene transfer was used to preexpose the recipient thymus to soluble donor-specific MHC class I molecules prior to heart transplantation in the high-responder ACI (RT1a) to Lewis (RT1l) rat strain combination. Specifically, cultured Lewis hepatocytes were transfected with DNA encoding a secreted form of the donor allo-MHC class I antigen, RT1.Aa. Seven days prior to ACI heart transplantation, genetically altered recipient-strain hepatocytes were injected into the thymus of Lewis recipients which also received a dose of antilymphocyte serum (ALS). Results showed that treatment with both ALS and soluble donor MHC-expressing hepatocytes prolonged transplant survival time by twofold, compared to injection of control hepatocytes and ALS. Therefore, intrathymic gene therapy delivery of soluble donor MHC molecules may be useful for promoting allograft survival in heart transplantation.

Intermediate-Term Outcome of Renal Retransplants in the Cyclosporine Era

To determine the influence of selected parameters on intermediate-term outcome of renal retransplants, univariate and multiple regression analyses were performed on all 100 consecutive cyclosporine treated retransplants performed between 1984 and 1990 (mean follow up, 4.6 +/- 2.3 years). Actual 1 year and actuarial 5 year graft survivals were higher in living compared with cadaver donor transplants (84% and 79% vs 69% and 56%, respectively; p < 0.05). Among cadaver donor transplant recipients, allografts with immediate early function had better 1 and 5 year graft survivals when compared with those with delayed function (81% and 62% vs 59% and 38%, respectively; p < 0.05). Recipients with acute rejection had inferior 1 year and 5 year graft survivals when compared with rejection free patients (65% and 35% vs 80% and 57%, respectively; p < 0.05). Graft survival time of primary transplants was also a significant predictor of retransplant outcome with 1 and 5 year graft survivals of 50% and 36%, respectively, in patients in whom primary grafts survived less than 3 months, compared with 75% and 58% in those in whom grafts survived longer than 3 months (p < 0.05). Recipient age, race, renal disease, and levels of panel reactive antibodies had no effect on intermediate-term outcome. In a multiple regression analysis, delayed graft function, acute rejection, and primary graft survival time less than 3 months correlated inversely with long-term survival of retransplants (multiple r = 0.65). A total of 39 grafts were lost due to rejection (22), sepsis (6), graft nonfunction (5), death with a functioning graft (4), noncompliance (1), and recurrent renal disease (1).(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired cystic kidney disease before and after renal transplantation

To determine the prevalence of acquired cystic kidney disease (ACKD), as reported in adults receiving long-term hemodialysis treatment, we studied 48 pediatric patients (aged 17 +/- 5.1 years) with end-stage renal disease by high-resolution ultrasonography or magnetic resonance imaging or both. Forty patients (83%) had a functioning renal transplant, with a mean transplant survival time of 3.4 years (range, 0.3 to 14.8 years); four patients were treated by hemodialysis and four by peritoneal dialysis. The mean duration of end-stage renal disease was 5.7 +/- 3.8 years. Ultrasonography detected ACKD in 12 (29%) of 42 patients, solitary cysts in 14 patients (33%), and no cysts in 16 patients (38%). In contrast, ACKD was diagnosed in only 3 of 37 patients studied by magnetic resonance imaging. In 31 patients studied by both imaging techniques. ACKD was diagnosed in three patients by magnetic resonance imaging but in 11 by ultrasonography. In patients with ACKD, the duration of end-stage renal disease was significantly longer, but renal (transplant) function was not different from that in patients with solitary cysts or no cysts. One patient with a history of 12 1/2 years of hemodialysis had multiple renal tumors that were diagnosed as renal cell carcinomas after bilateral nephrectomy. These results indicate that young patients with end-stage renal disease should be monitored regularly for the presence of ACKD, preferably by ultrasonography, even after successful renal transplantation.

Animal experimental studies on the free transplantation of smooth colon muscles as an artificial sphincter in the rat

Free autologous muscle transplants were performed on 59 Wistar rats of 70 to 90 days of age according to the method described by Schmidt (1978). The free smooth muscular transplant was prestretched by 0%, 100%, 120%, 150% and 200% and the animals were sacrificed on the 5th, 10th, 20th, 40th and 60th postoperative day, respectively. Five animals died postoperatively, of these three during ileus and stenosis after more than 150% prestretching of the transplant. Complications occurred in eleven further animals, which included again ileus phenomena nine times due to stenosing or disturbance of defecation, also as a result of obstruction phenomena. Complications always occurred in animals with more than 150% transplant prestretching. No relaxation reflex was observed manometrically in any of the transplants. Budding of nerve fibres also did not occur in any of the cases, neither from the plexus myentericus of the inner intestinal wall nor from outside. Histology revealed already after five days' survival leucocytous infiltration and connective tissue multiplication which increased with increasing prestretching of the transplant and longer survival time of the animals until complete metaplasia of the connective tissue. In preparations with 100 up to 120% prestretch not more than 20% of the original muscular mass was preserved. With prestretching of 150% and more the transplant underwent complete fibrosis. On the basis of these studies we must discourage performance of free transplants of smooth-muscle colon segments in newborn and young infants.

Effect of acetylsalicylate on surgical bleeding, postoperative mortality and allograft survival in rats undergoing heart transplantation

18 rats were treated with L-ASA before heart transplantation and daily thereafter until death or rejection. 22 animals acted as controls. A significantly higher post-operative mortality rate, without any significant modification of the transplant survival time, was found in L-ASA-treated group.

Active Enhancement of Heart Transplants in the Inbred Rat with Donor Strain Blood

Prolongation of survival time of heart transplants in inbred rats following intravenous injection of donor strain blood according to various time-dose schedules is described. The immunological status of long-term survivors shows detectable antidonor antibodies, normal graft-versus-host reactions and rejection of skin grafts in the usual time. Lymphocytotoxic activity is well related to the survival time of the heart in those rats which respond to the treatment.

Correlation between Skin-Lymphocyte Culture Test (SLC Test) and Skin Allograft Survival in Mice

SLC test with the mixed culture of the donor's skin and recipient's lymphocytes, was investigated for tissue typing in mice. Mice used were C3H/He (H-2k), CBA (H-2k) and (C3H/He × C57BL/6) F1. SLC test was carried out with a stationary monolayer culture in Eagle's basal medium containing 0.25% phytohemagglutinin-P for 72 hours. The extent of the reaction was estimated by both the frequency of the appearance of blast-like cells on morphological observation, and the number of the aggregated lymphocytes surrounding the skin in Ehrlich's sight. The extent of the blast formation and aggregation of lymphocytes was compared with the survival time of the skin grafts in various combinations of donors and recipients. A significant correlation between the result of SLC test and the transplant survival time was found.

Experimental xenografting in closely related species (cat-dog) (author's transl)

In order to study the survival time of transplants in closely related species, kidney of cats were transplanted into mongrel dogs using an ‘<i>en bloc</i> technique’. A delayed type of hyperacute xenogeneic rejection was found. Beginning of rejection at an early stage was indicated by a decrease of serum complement during the first 6 h. At the same time cat protein and considerable amounts of potassium were found in urine samples. Though there was good evidence for severe damage of the transplanted organs, complete loss of function could not be ascertained for up to 15–24 h. The end stage of the antigen-antibody reaction is characterized by an increase of complement values towards normal. Final rejection of the transplant is probably due to nonspecific mechanism.