Acute renal endothelial injury during marrow recovery in a cohort of combined kidney and bone marrow allografts

An idiopathic capillary leak syndrome ('engraftment syndrome') often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10-16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68(+) MPO(+) mononuclear cells and CD3(+) CD8(+) T cells, the latter with a high proliferative index (Ki67(+) ). B cells (CD20(+) ) and CD4(+) T cells were not detectable, and NK cells were rare. XY FISH showed that CD45(+) cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti-rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2-4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.

Comparison of outcomes after transplantation of peripheral blood stem cells versus bone marrow following an identical nonmyeloablative conditioning regimen

This is the first study to examine the outcomes in 54 patients with hematologic malignancies who received an HLA-matched related donor bone marrow (BM, n = 42) or GCSF-mobilized peripheral blood stem cells (PBSC, n = 12) following identical nonmyeloablative conditioning with the intention of induction of mixed chimerism (MC) followed by prophylactic donor leukocyte infusion (pDLI) to convert MC to full donor chimerism (FDC) and capture a graft-versus-tumor effect without clinical graft-versus-host disease (GVHD). Neutrophil and platelet recovery were faster and transfusion requirement was less in PBSC recipients (P < 0.05). A total of 48% of BMT recipients achieved FDC with a median conversion time of 84 days, including 13 following pDLI. In contrast, 83% (P = 0.04) in the PBSC group had spontaneous FDC at a median of 14 days, precluding the administration of pDLI. There was no significant difference in the incidences of acute or chronic GVHD, though the rates of chronic GVHD were considerably higher in PBSC group than in the BM group (6/7, 86% vs 10/24, 42%). CD4 and CD8 T-cell recovery was faster in PBSC recipients. In PBSC recipients, a higher number of CD34+ cells was associated with increased rates of severe, grade III-IV acute GVHD.

Significance of Anti-HLA and Donor-Specific Antibodies in Long-Term Renal Graft Survival

Numerous studies have demonstrated an association of posttransplant HLA antibodies with decreased long-term graft survival. The presence of C4d deposition in these cases supports the hypothesis that antibody and complement deposition are involved in the pathogenesis of graft failure. Development of HLA antibodies may predate the clinical manifestation of chronic rejection (CR). However, frequency of donor-specific antibody is low when all patients are screened regardless of their graft function, and it may be more valuable to look for antibody only in patients with mild dysfunction. Effective treatment for CR has not been identified, although increased immunosuppression has been shown to decrease antibody levels and stabilize graft function. Many patients have been identified with good graft function despite the presence of circulating donor-specific HLA antibody. Additional studies focusing on the mechanism behind the apparent protection from the detrimental effects of antibody in such patients are needed.

The problem of late allograft loss in kidney transplantation

The 2 principal factors implicated in late kidney allograft failure are chronic rejection (also called chronic allograft nephropathy) and death of the patient with a functioning graft (mainly from cardiovascular causes). Despite lifelong immunosuppression of the recipient, immunological responses remain the leading factor in the pathogenesis of chronic rejection and both cellular and humoral immune mechanisms have been shown to play important roles. In this review, we highlight the relevance of humoral mechanisms of rejection to the pathogenesis of late allograft loss. Non immunological factors, such as donor organ quality, initial ischemic injury, calcineurin inhibitor (CNI) toxicity, hypertension, and hyperlipidemia, also contribute to progressive chronic allograft injury, but will not be reviewed in detail here. Possible strategies to stabilize or improve allograft function in patients with already established "chronic rejection/chronic allograft nephropathy" (CR/CAN) are the addition of mycophenolate mofetil (or sirolimus) with or without a reduction of cyclosporine dosage, or conversion from cyclosporine to tacrolimus. However, prospective randomized clinical trials are needed to test the efficacy of these strategies. A major current challenge for transplant physicians is to develop regimens that prevent CR/CAN, since, once established, the process typically progresses inexorably to renal allograft loss in most recipients. Evidence is now accumulating that new immunosuppressive regimens must control not only T cell but also B cell responses (i.e. limit antidonor antibody production) in order to prevent CR/CAN and improve long-term allograft survival.

The kidney transplant program at the Massachusetts general hospital

Between February 1963 and December 2000, 1,627 kidney transplants were performed at the Massachusetts General Hospital. The majority (62%) were from cadaveric donors, although in recent years (1996-2000) 52% have been allografts from living donors, with an increase in living unrelated donors. The introduction of CsA and OKT3 in 1984 was associated with a significant improvement in actuarial renal allograft survival, although a persistent late attrition of allografts continues beyond the first year after transplantation. As reported in other centers, current actuarial survival for living unrelated allografts is superior to that of cadaveric allografts, and is quite similar to that observed in recipients of non-HLA identical living-related transplants. Our preliminary laparoscopic donor nephrectomy experience is encouraging as excellent allograft survival and function has been observed, with minimal morbidity associated with the procedure and a low rate of conversion to open nephrectomy. Recent changes in immunosuppressive protocols have resulted in lower early acute rejection rates, however the incidence of delayed graft function remains unchanged in cadaveric renal transplantation. The role of humoral immunity in allograft rejection has been progressively clarified and new approaches to control donor specific alloantibody production have been shown to be effective. Current clinical studies are ongoing to determine the optimal type and dose of calcineurin inhibitors beyond the first year after transplantation and to study whether avoidance of steroids is safe and feasible. Finally, an innovative tolerance induction protocol using the mixed chimerism approach has been successfully accomplished in selected patients with end-stage renal disease secondary to multiple myeloma. These encouraging observations emphasize that major changes from current immunosuppressive regimens are likely to occur over the next few years as more approaches to tolerance induction are explored clinically.

Successful allogeneic stem cell transplantation with nonmyeloablative conditioning in patients with relapsed hematologic malignancy following autologous stem cell transplantation

The use of myeloablative preparative therapy and allogeneic stem cell transplantation (alloSCT) as salvage therapy for adult patients with relapsed hematologic malignancy after autologous stem cell transplantation (autoSCT) is generally unsuccessful due to very high treatment-related mortality rates. We evaluated the outcome of HLA-matched related donor alloSCT following nonmyeloablative preparative therapy in 13 patients (median age, 38 years) with relapsed hematologic malignancies (Hodgkin's disease, n = 4; Hodgkin's disease and advanced myelodysplastic syndrome, n = 1; non-Hodgkin's lymphoma, n = 6; multiple myeloma, n = 2) after initial autoSCT. Median time from autoSCT to alloSCT was 12 months (range, 3-24 months); 6 patients had chemotherapy-refractory disease following autoSCT, 6 were in untreated relapse, and 1 had a partial response from salvage chemotherapy. Preparative therapy consisted of cyclophosphamide, 150-200 mg/kg; peritransplantation anti-thymocyte globulin; thymic irradiation (in patients who had not received previous mediastinal irradiation); and a very short course of cyclosporine as GVHD prophylaxis. All patients achieved initial mixed chimerism as defined by greater than 1% donor peripheral white blood cells. Seven patients, who had no evidence of GVHD, received prophylactic DLI beginning 5 to 6 weeks after transplantation for conversion of mixed chimerism to full donor hematopoiesis and to optimize a graft-versus-tumor effect. Six patients showed conversion to full donor chimerism and 1 lost the graft. Grade II or greater acute GVHD occurred in 9 patients. Seven patients achieved a complete response; 6 had no response. The median survival time of the 13 patients is currently 10 months (range, 3-39 months), with an overall survival probability at 2 years of 45% (95% confidence interval [CI], 19%-73%) and a disease-free survival probability at 2 years of 37.5% (95% CI, 12%-65%). Thus, this novel nonmyeloablative alloSCT strategy followed by prophylactic DLI was well tolerated and can result in durable disease-free survival among patients with advanced hematologic malignancies after a failed autoSCT. Further follow-up and evaluation of additional patients are required to conclusively establish the role of this strategy in the treatment of hematologic malignancies after an autologous transplantation.

Intentional induction of mixed chimerism and achievement of antitumor responses after nonmyeloablative conditioning therapy and HLA-matched donor bone marrow transplantation for refractory hematologic malignancies

Mixed lymphohematopoietic chimerism can be induced in mice with bone marrow transplantation (BMT) after a nonmyeloablative preparative regimen that includes cyclophosphamide, anti-T-cell antibody therapy, and thymic irradiation. These mixed chimeras are resistant to the induction of graft-versus-host disease (GVHD) after delayed donor leukocyte infusions (DLIs), despite a potent lymphohematopoietic graft-versus-host reaction that converts the mixed chimeric state to a full donor one. Based on this animal model, we initiated a trial of nonmyeloablative therapy with HLA-matched or -mismatched donor BMT and DLI for refractory hematologic malignancies. Twenty-one of 36 patients enrolled in this trial received a genotypically (n = 20) or phenotypically (n = 1) HLA-matched donor transplant; results reported here are for those patients only. Preparative therapy consisted of cyclophosphamide in doses of 150 to 200 mg/kg; peritransplant antithymocyte globulin; thymic irradiation (in patients who had not received previous mediastinal radiation therapy); and cyclosporine. Eighteen of 20 evaluable patients developed persistent mixed lymphohematopoietic chimerism as defined by >1% donor peripheral white blood cells until at least day 35 posttransplantation. Ten patients received prophylactic DLI beginning 5 to 6 weeks after BMT for conversion of mixed chimerism to full donor hematopoiesis and to optimize a graft-versus-leukemia effect. Fourteen of 20 evaluable patients (70%) achieved an antitumor response; 8 of these responses were complete, and 6 were partial. Of the 8 evaluable patients who received prophylactic DLI, 6 showed conversion to full donor chimerism. Five of the 9 evaluable patients (56%) who received prophylactic DLI achieved a complete response, compared with 3 of 11 patients (27%) who did not receive prophylactic DLI. Currently 11 patients are alive, and 7 of these are free of disease progression at a median follow-up time of 445 days (range, 105-548 days) posttransplantation. Transplantation-related complications included cyclophosphamide-induced cardiac toxicity in 3 of 21 patients (14%) and grade II or greater GVHD in 6 patients (29%). One patient (5%) died from a complication of BMT, and 1 patient (5%) died from GVHD after 2 prophylactic DLIs were given for conversion of chimerism. In summary, mixed lymphohematopoietic chimerism was reproducibly induced after a novel nonmyeloablative preparative regimen incorporating chemotherapy, peritransplant antithymocyte globulin, and thymic irradiation, allowing for early administration of DLI in 10 of 21 patients. After treatment, striking antitumor responses were observed in the majority of patients with chemotherapy-refractory hematologic malignancies.

Anti-Galalpha1-3Gal antibody levels in organ transplant recipients receiving immunosuppressive therapy

The effect of long-term pharmacologic immunosuppression (PI) on anti-Galalpha1-3Gal (alphaGal) antibody (Ab) levels has not been determined previously in humans. In this study, we measured alpha Gal Ab levels by ELISA in 14 healthy volunteers (controls) and in 70 patients with grafts (kidney, heart, liver) who had received different combinations of PI (including cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, and steroids) for >3 months. There was great variation in Gal IgM (<80-fold) and IgG (<160-fold). There was no difference in Gal IgM or Gal IgG between any one group and any other. In kidney patients with either high (mean 68%) or low (mean 6%) panel-reactive alloantibodies, there was no difference in alpha Gal Ab level or serum cytotoxicity to pig cells. In vitro immunoadsorption of alphaGal Ab from the serum did not change panel-reactive alloantibody positivity. Therapy with OKT3, a mouse product that might stimulate alphaGal Ab production, led to no significant change in patient Ab levels. We conclude that long-term (>3 months) PI does not reduce Gal Ab levels sufficiently to be of clinical value in xenotransplantation.

Combined histocompatibility leukocyte antigen-matched donor bone marrow and renal transplantation for multiple myeloma with end stage renal disease: the induction of allograft tolerance through mixed lymphohematopoietic chimerism

BACKGROUND

Experimental and clinical evidence has demonstrated that the establishment of allogeneic chimerism after bone marrow transplantation may provide donor-specific tolerance for solid organ allografts.

METHODS

Based on the preliminary results of a clinical trial using nonmyeloablative preparative therapy for the induction of mixed lymphohematopoietic chimerism, we treated a 55-year-old woman with end stage renal disease secondary to multiple myeloma with a combined histocompatibility leukocyte antigen-matched bone marrow and renal transplant after conditioning with cyclophosphamide, antithymocyte globulin, and thymic irradiation.

RESULTS

The posttransplant course was notable for early normalization of renal function, the absence of acute graft-versus-host disease, and the establishment of mixed lymphohematopoietic chimerism. Cyclosporine, which was the only posttransplant immunosuppressive therapy, was tapered and discontinued on day +73 posttransplant. No rejection episodes occurred, and renal function remains normal on day + 170 posttransplant (14 weeks after discontinuing cyclosporine). Although there is presently no evidence of donor hematopoiesis, there is evidence of an ongoing antitumor response with a recent staging evaluation showing no measurable urine kappa light chains. The patient remains clinically well and is off all immunosuppressive therapy.

CONCLUSION

This is the first report of the deliberate induction of mixed lymphohematopoietic chimerism after a nonmyeloablative preparative regimen to treat a hematological malignancy and to provide allotolerance for a solid organ transplant.

Plasma exchange and tacrolimus-mycophenolate rescue for acute humoral rejection in kidney transplantation

BACKGROUND

Acute renal allograft rejection associated with the development of donor-specific alloantibody (acute humoral rejection, AHR) typically carries a poor prognosis. The best treatment of this condition remains undefined.

METHODS

During a 14-month period, 73 renal transplants were performed. During the first postoperative month, five recipients (6.8%) with AHR were identified. The diagnosis was based on: (1) evidence of severe rejection, resistant to steroid and antilymphocyte therapy; (2) typical pathologic features; and (3) demonstration of donor-specific alloantibody (DSA) in recipient's serum at the time of rejection. Pretransplant donor-specific T- and B-cell cross-matches were negative.

RESULTS

Plasma exchange (PE, four to seven treatments per patient) significantly decreased circulating DSA to almost pretransplant levels in four of five patients, and improvement in renal function occurred in all patients. One patient had recurrent renal dysfunction in the setting of an increase in circulating DSA. A second series of five PE treatments decreased DSA and reversed the rejection episode. Rescue therapy with tacrolimus (initial mean dose: 0.14+/-0.32 mg/kg/day) and mycophenolate mofetil (2 g/day) was used in five of five and four of five patients, respectively. With a mean follow-up of 19.6+/-5.6 months, patient and allograft survival are 100%. Renal function remains excellent with a mean current serum creatinine of 1.2+/-0.3 mg/dl. (range: 0.9-1.8 mg/dl).

CONCLUSIONS

Our findings suggest that a therapeutic approach combining PE and tacrolimus-mycophenolate mofetil rescue has the potential to improve the outcome of AHR.

Phenotypic and functional characteristics of colonic lymphocytes isolated from patients with primary sclerosing cholangitis and inflammatory bowel disease

Because primary sclerosing cholangitis (PSC) frequently is associated with inflammatory bowel disease, the phenotypic and functional characteristics of lymphocytes isolated from colonic mucosa were studied in patients with primary sclerosing cholangitis (PSC), patients with ulcerative colitis and patients with other colonic and hepatic disorders. To accomplish this, lymphocytes isolated from colonic biopsies obtained at the time of colonoscopy were expanded in vitro in the presence of interleukin 2 (IL2). Cell propagation was similar in patients with PSC with or without associated inflammatory bowel disease but was diminished significantly when compared to results obtained in patients with ulcerative colitis not associated with PSC. The CD4:CD8 ratio of the propagated lymphocytes was increased in patients with PSC compared to controls. The Leu 19+ subset of cells was also increased in PSC patients. In patients with inflammatory bowel disease, increased cytotoxicity was noted at low effector to target cell ratios with SK-HEP (hepatocellular carcinoma) but not RPMI 7451 (cholangiocarcinoma) targets. No differences between PSC patients and controls were observed for NK sensitive and NK resistant targets. Based upon these studies it can be concluded that: 1) expansion of lymphocytes obtained from endoscopic colonic biopsies using recombinant IL2 represents an alternative method by which intestinal lymphocytes can be studied; 2) natural killer cells are increased in the colonic mucosa of patients with primary sclerosing cholangitis; 3) colonic cytotoxic T lymphocytes may be more active in patients with chronic liver disease and particularly those with associated inflammatory bowel disease.

Morphologic and immunophenotypic characterization of a cell line derived from liver tissue with Epstein-Barr virus associated post-transplant lymphoproliferative disease

A B-cell line was established from the liver of an 11-yr-old boy with Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD). The cells were morphologically heterogenous, CD10 (CALLA) negative, and expressed several B-cell antigens, including CD23, in a manner reminiscent of lymphoblastoid cell lines (LCLs) reported in the literature. However, the cells also showed expression of the CD77 antigen, carried a 14q32+ chromosomal anomaly, and showed IgM-kappa immunoglobulin isotype restriction immediately after their outgrowth in culture. These latter properties are typically associated with Burkitt's lymphoma cell lines rather than LCLs. Aberrant expression of the L60 antigen on these B-cells was found as additional evidence of altered growth regulation in these cells. EBV infection was demonstrated by the abundant expression of EBNA-2 and LMP viral antigens in culture. The cell line described should be useful in planning in vitro experiments designed to understand the factors that modulate the growth of PTLD in vivo.

Second renal transplantations. Ethical issues clarified by outcome; outcome enhanced by a reliable crossmatch

OBJECTIVE

To determine whether the appropriate use of scarce donor resources has been accomplished by renal retransplantation by reviewing the initial and long-term outcomes of second-renal transplant recipients at the Massachusetts General Hospital, Boston.

PATIENTS AND RESULTS

With a mean follow-up of nearly 5 years following transplantation, 54 (68%) of 80 second-transplant recipients had functioning allografts (allograft failure was defined by patient death or a return to dialysis). Rejection was the most common cause of failure (14 [54%] of 26 patients). The 1-, 3-, and 5-year actuarial allograft survival rates were 86%, 78%, and 69%, respectively, which were not significantly different from the survival rates of primary allografts at this center. These results support the continued approach of providing both cadaver-donor and living-donor renal allografts for recipients whose primary renal allograft has failed. The antiglobulin crossmatch may have contributed to the successful outcome by accurately determining compatibility and by averting early rejection failures.

CONCLUSIONS

Health care policy reviewers should clearly distinguish the prospects for successful second renal transplants from the outcomes of extrarenal retransplantation. Moreover, because excellent second-renal allograft survival is attainable and comparable to primary-renal allograft survival and because the costs are comparable, restricting suitable patients to subsequent lifelong dialysis becomes unethical.

Pathologic analysis of liver transplantation for primary biliary cirrhosis

A retrospective histopathologic review of all pathologic specimens from 394 adult liver transplant patients was undertaken with clinical correlation to determine if primary biliary cirrhosis has affected the posttransplant course compared to all other indications for liver transplantation and if recurrent primary biliary cirrhosis has occurred after liver transplantation. We also compared the histopathologic features seen in native livers with primary biliary cirrhosis to failed allografts with chronic rejection. One hundred six of the 394 adult patients transplanted during this time (1981 to July, 1986) fulfilled clinicopathologic criteria for a diagnosis of primary biliary cirrhosis. Neither the incidence nor any qualitative pathologic feature of histologically documented acute cellular rejection differentiated subjects transplanted for primary biliary cirrhosis vs. other diseases. No correlation between the titers of antimitochondrial antibody and the presence of posttransplant hepatic dysfunction based on liver enzyme profiles or the development of chronic rejection was seen in patients transplanted for primary biliary cirrhosis. Minor differences noted in the posttransplant course of primary biliary cirrhosis patients as compared to other conditions (higher incidence of chronic rejection as a cause of graft failure) was seen, but this did not significantly affect graft or patient survival. Recurrent primary biliary cirrhosis could not be diagnosed with certainty in any patient. A comparison of failed chronically rejected allografts vs. native hepatectomies obtained from patients with primary biliary cirrhosis revealed the presence of chronic obliterative vasculopathy, centrilobular cholestasis, and lack of granulomas, cirrhosis, cholangiolar proliferation, copper-associated protein deposition and Mallory's hyalin in specimens with chronic rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation and primary cultures of human intrahepatic bile ductular epithelium

A technique for the isolation of human intrahepatic bile ductular epithelium, and the establishment of primary cultures using a serum- and growth-factor-supplemented medium combined with a connective tissue substrata is described. Initial cell isolates and monolayer cultures display phenotypic characteristics of biliary epithelial cells (low molecular weight prekeratin positive; albumin, alphafetoprotein, and Factor VIII-related antigen negative). Ultrastructural features of the cultured cells show cell polarization with surface microvilli, numerous interepithelial junctional complexes and cytoplasmic intermediate prekeratin filaments.

Elevated natural killer cytotoxicity in HLA-B8 and HLA-DR3-positive individuals

Increased natural killer cytotoxicity in persons positive for HLA-B8 and HLA-DR3 has been found. It is suggested that linkage disequilibrium between the genes coding for HLA-B8 and HLA-DR3 may have evolved as a result of strengthened immunological surveillance in individuals bearing them, as decrease in the frequency of both these antigens has recently been reported in patients with tumours.