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Background: We update more favorable 10-year deceased donor kidney transplant survival in 63 recipients infused perioperatively with donor vertebral body bone marrow (DBMC-i) vs. 219 noninfused controls having equivalent immunosuppression and demographics. We questioned if this was associated with putatively regulatory FoxP3 mRNA and cell phenotypes (CD4+CD25+high percentages and high DC2:DC1 ratios) in DBMC-i vs. noninfused controls., Methods: Baseline studies were performed on peripheral blood lymphocytes (PBLs) vs. marrow in normal laboratory volunteers of CD4+CD25+high percentages and DC2:DC1 by flow cytometry, and FoxP3 mRNA in CD3+ cells by real-time polymerase chain reaction. Similar studies were performed on PBL of the majority of the 10-year patients remaining with graft function: 21 (of the remaining 37) DBMC-i vs. 55 (of the remaining 105) controls., Results: In normal subjects, all parameters were significantly higher in marrow than in PBL, supporting our previous reports of ex vivo DBMC immunoregulation. At 9.8+/-.02 years posttransplant in DBMC-i vs. controls, death-censored percent graft failure was 17.5% vs. 32.9% (P=0.02) with 247.6+/-24 vs. 79.9+/-3.1 (mean+/-SE) FoxP3 copies/5,000 CD3+ cells (P=0.0001). PBL CD4+CD25+high percentages were lower, but DC2:DC1 values higher in both recipient groups than in end-stage renal disease patients who had lower FoxP3 levels (40.8+/-5.9, P<0.0001), consistent with non-CD4+CD25+high T regulatory cells generated long-term posttransplant. Individual higher FoxP3 values correlated with higher iliac crest chimerism in DBMC-i, but not in controls (with 50-fold lower chimerism). In chronically rejecting controls, FoxP3 was further decreased., Conclusions: Peritransplant DBMC-i has higher 10-year renal transplant acceptance, chimerism, and FoxP3 mRNA in thus-far unclarified regulatory cell phenotypes.

Killer cell immunoglobulin-like receptors (KIR) on natural killer cells mediate killing by recognizing class I presentation of peptides by infected or oncogenic cells. KIR differences in stem cell transplants have been implicated in increased graft vs host disease. Human leukocyte antigen (HLA)-matched-related kidney recipients have the best graft survival as compared to one haplotype-matched recipients. These HLA-identical transplant pairs may be ideal for studying minor HLA antigens and KIR polymorphic differences and their relation to graft function. We have studied KIR polymorphism in recipients and donor pairs of HLA-matched sibling kidney transplants to demonstrate differences in genotype as related to long-term graft function and/or chronic rejection. We employed a KIR genotyping kit (Dynal, Brown Deer, WI), that uses sequence-specific priming by PCR to identify 19 alleles for genotypes in 12 donor/recipient (D/R) pairs at least 1 year posttransplant. There were two pairs that had different alleles in the recipient that were not found in the donor. One pair had different alleles found in the donor that were not present in the recipient. Two pairs had difference in alleles in both the donor and recipient. Seven of the 12 pairs had the same KIR genotype. Eight of the 12 pairs (both donor and recipient) exhibited a haplotype with 2DL2+ and 2DS2+. Four of the 12 exhibited a haplotype 2DL2- and 2DS2-. Three out of four of these recipients had increased creatinine levels and at least one graded rejection episode. One of these three has lost their graft. In conclusion, the genotyping of HLA-matched sibling kidney transplant D/R pairs demonstrates that there may be an association of higher risk for poor graft function when both genotypes lack 2DL2 and 2DS2.

Background: New trends in immunosuppression in clinical transplantation include the use of antibody induction agents in protocols that emphasize reduction or avoidance of steroids and calcineurin inhibitors., Methods: In a randomized trial using three different antibody induction agents in 90 first renal transplant recipients from cadaver donors, group A received Thymoglobulin, group B received Alemtuzumab, and group C received Daclizumab. Maintenance immunosuppression included tacrolimus and mycophenolate in all three arms, and methylprednisolone in groups A and C only (standard clinical institutional practice). The targeted trough level of tacrolimus was between 8 and 10 ng/mL for groups A and C, respectively, with a targeted mycophenolate dose of 1 g twice daily. However, in group B, the target tacrolimus trough level was 4 to 7 ng/mL to reduce long-term nephrotoxicity, with 500 mg twice-daily doses of mycophenolate, without steroid maintenance., Results: In this 15-month median postoperative interval report, there were no notable differences in demographics and patient and graft survivals. Acute rejection rates at 1 year were equivalent, that is, 5 of 30 in all three groups (16.6%). In group B, there was slightly lower renal function at 1 month, but no difference at 1 year. There was also significantly more leukopenia, but a greater percentage of T-regulatory cells and number of Fox-P3 mRNA copies by flow cytometry and semiquantitative polymerase chain reaction analysis, respectively, in group B., Conclusions: This preliminary analysis indicates that 80% of the patients in group B remained steroid-free 1 year postoperatively, with lower tacrolimus trough levels and no difference in other adverse events.

Cytomegalovirus, seen in more than 50% of solid organ transplant recipients, is responsible for numerous direct and indirect consequences, including infection with opportunistic pathogens and allograft rejection. Prophylaxis with intravenous ganciclovir has been the gold standard for prevention; however, intravenous treatment is expensive and carries risks of its own. Oral ganciclovir, to be effective, must be given in large, divided doses. Valganciclovir, the valine ester of ganciclovir, at 900 mg/day, provides oral bioavailability equivalent to that of intravenous ganciclovir and superior to that of oral ganciclovir. This retrospective study assessed the efficacy of 3 months prophylaxis with valganciclovir in kidney, simultaneous pancreas-kidney, and pancreas transplantation. Of 161 patients, all of whom received potent immunosuppressive regimens and were followed for a mean of 440 days, only one developed cytomegalovirus infection, at 120 days post-transplantation. Two patients died, and two others lost their grafts. There were seven incidents of acute rejection. Only seven patients discontinued treatment early, five because of leukopenia. These results suggest that prophylaxis with 900 mg/day of valganciclovir for at least 3 months safely and effectively prevents cytomegalovirus infection in kidney, simultaneous pancreas-kidney and pancreas transplant recipients on highly potent immunosuppression.

To evaluate the incidence of adenovirus (AdV) infection in pediatric liver and intestinal transplant recipients, the records of patients with possible AdV infection were reviewed for demographic data, symptomatology, methods of diagnosis, treatment and outcome. To evaluate the impact of polymerase chain reaction (PCR) amplification and identification of AdV DNA as a diagnostic test, the incidence and outcome of AdV before and after the introduction of PCR were compared. Adenovirus infection was identified in 4.1% of liver recipients and 20.8% of intestinal transplant recipients. The overall incidence of AdV did not increase over time, even following the introduction of PCR for virus detection. The higher incidence of AdV in the pediatric intestinal transplant recipients may be attributed to the frequent application of PCR methodology to intestinal biopsy material. Detection of AdV by PCR was associated with reduced mortality compared with detection by culture, either because of earlier detection of invasive disease or because PCR detects the presence of latent as well as active AdV.

Background: Posttransplant Epstein-Barr virus-associated B-cell lymphoproliferative disease (PTLD) has a higher incidence after intestinal transplantation than after transplantation of other solid organs and is associated with a high mortality. A new anti-CD20 monoclonal antibody, rituximab, has shown efficiency in the treatment of B-cell lymphoma, including PTLD, but its use has not yet been reported in intestinal transplant recipients., Methods: We retrospectively reviewed five patients who were diagnosed with PTLD from March 1999 to August 2001, after intestinal transplantation. These patients were primarily managed with rituximab, associated with reduction or interruption of immunosuppression and antiviral therapy with ganciclovir and cytomegalovirus immune globulin. Rituximab was administered at weekly doses of 375 mg/m until full remission was ascertained, and the interval between doses was then increased. No patient received chemotherapy., Results: One patient had nonmalignant lymphoproliferation, and four had malignant PTLD, as assessed by histopathology and monoclonality of the tumor. Two pediatric patients had severe generalized disease. All patients had received OKT3 as treatment of rejection before developing PTLD. All tumors showed proliferation of CD20 cells and were positive for Epstein-Barr virus by in situ hybridization. All patients responded to rituximab therapy and have achieved full remission with a follow-up of 3 to 30 (median, 8) months., Conclusion: Prolonged rituximab treatment, in association with reduction of immunosuppression and antiviral therapy, is highly efficient as part of the first-line treatment of CD20 B-cell PTLD after intestinal transplantation.

Background: Hepatitis C infection recurs after orthotopic liver transplantation for hepatitis C virus (HCV)-related end-stage liver disease. Overlapping histopathologic features may present difficulties in differentiating recurrent HCV in the allograft from other conditions, especially rejection., Methods: In this study, we evaluated the presence of HCV-RNA by reverse transcriptase in situ polymerase chain reaction (RT in situ RCR) in hepatic tissue, after orthotopic liver transplantation for HCV-related liver disease. Further, detection of HCV-RNA was correlated with the serum HCV-RNA levels, histopathology, and clinical outcome., Results: Twenty-five patients were part of this study. Seventeen patients were transplanted for HCV cirrhosis and eight for an underlying disease other than HCV. None of the patients in the non-HCV group had in situ RT-PCR detection of HCV-RNA. Positive RT in situ PCR for HCV was found in 9 of 17 HCV patients, and the patients had a clinical course consistent with recurrent hepatitis C disease. Four of these nine patients had an initial histologic diagnosis of rejection. The other eight patients in the HCV group had negative RT in situ PCR, and none of them had a course compatible with recurrent HCV disease, although four patients were histologically diagnosed as having chronic C hepatitis. The mean HCV-RNA level (log/mL) in the patients who had in situ detection of HCV-RNA was 7.01+/-0.26. Although RT-PCR was negative in 8 of 17 HCV patients, the patients were serologically viremic and the mean HCV-RNA level was 6.05+/-0.33 (P=0.03)., Conclusions: Our findings indicate that the HCV in situ RT-PCR assay may be helpful in the differentiation of recurrent hepatitis C disease from rejection. This may further help in the adjustment of immunosuppression.

We have previously demonstrated that the successful transfer of rat chloroleukemia (Mia C51) cells to newborn rats is related to the host's inability to generate adequate levels of differentiation factor (DF). Thus, when the appropriate amount of DF was injected into rats bearing MIA C51 cells, the development of chloroleukemia was aborted. In the present study, we provide evidence that stimulation of endogenous differentiation activity (DA) production by the administration of a biologic response modifier (Imuvert) will like-wise abort the development of chloroleukemia. Imuvert at 50 micrograms/ml had no direct effect on growth, viability, or differentiation of MIA C51 cells. However, when monocytes from young rats or adult rats were stimulated with Imuvert in vivo or in vitro, there was significant increase in DA production. Treatment of young rats with Imuvert aborted the development of chloroleukemia from transplanted MIA C51 cells. It is concluded that stimulation of endogenous DA production may provide a potentially useful approach in the treatment of leukemia.

Infantile genetic agranulocytosis (IGA) has a high morbidity and mortality rate due to severe neutropenia. The pathogenetic mechanisms of this syndrome have not been elucidated. However, a recent clinical trial with recombinant human granulocyte-colony-stimulating factor (rhG-CSF) has shown a dramatic increase in the absolute neutrophil count in patients with IGA. This suggests that these patients have either a lack of granulocyte-colony-stimulating factor (G-CSF) or have a defect in the G-CSF receptors. A clinical trial of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) in an infant with IGA is reported in this article. A marked eosinophilic response was observed without any increase in the absolute neutrophil count (ANC). In an effort to elucidate the pathogenetic mechanism underlying IGA, we examined (a) the in vitro response of patient's CFU-GM to rhGM-CSF and to rhG-CSF and (b) the ability of patient's monocytes to produce G-CSF. Our results tend to support the thesis that the defect in IGA is at the G-CSF receptor level. We also found a lack of correlation between in vivo and in vitro response to rhGM-CSF.