The role of cysteinyl-LT(1)receptor (CysLT(1)R) in renal ischemia-reperfusion injury.

The pathogenesis of ischemia-reperfusion (I/R) injury is known to involve cytokines and particularly surface adhesion molecules, the expression of which initiates the attachment of inflammatory cells. Renal I/R injury, a clinically important problem, is an invariable consequence of renal transplantation. The problem begins at the onset of acute tubular necrosis (ATN), when the transplantation includes a long ischemic interval or by use of a cardiac arrest donor's kidney. The cysteinyl leukotriene-1 (CysLT(1)), a potent lipid mediator in allergic disease, acts through the CysLT(1)R receptor. We researched the expression of CysLT(1)R in rat renal I/R injury as well as correlations with the degree of ATN. The right kidney was harvested and the left renal artery and vein were clamped at laparotomy. The kidney was reperfused after 90 minutes of ischemia; rats were sacrificed at 0, 3, 5, 12, and 24 hours after reperfusion. CysLT(1)R expression was analyzed by immunohistochemistry. CysLT(1)R expression was observed only in endothelial cells of a normal kidney. CysLT(1)R expression was most intense on endothelial cells at 3 hours after reperfusion, and CysLT(1)R expression on endothelial cells gradually became weaker. Twelve hours after reperfusion, ATN extended throughout the ischemic kidney. Renal I/R injury gradually progressed at time after reperfusion. Several hours after the maximal CysLT(1)R expression, we observed the maximum renal I/R injury.

Study of cysteinyl leukotriene-1 receptor in rat renal ischemia-reperfusion injury.

Renal ischemia-reperfusion (I/R) injury is a major cause of renal transplant dysfunction. Recent studies of I/R injury have focused on the function of neutrophils, the mechanisms of action of inflammatory cytokines, and oxygen free radicals, as well as other mediators. However, few reports address the cysteinyl leukotriene-1 receptor (CysLT1R), an important mediator of bronchial asthma in human beings. We examined the expression of CysLT1R in rat renal I/R injury. At laparotomy, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 minutes of ischemia, and the rats were killed after 0, 3, 5, 12, or 24 hours. Expression of CysLT1R analyzed at immunohistochemistry was observed only in endothelial cells in nonischemic kidney. At 0 to 3 hours after reperfusion, CysLT1R expression on endothelial cells gradually became stronger, being most intense at 3 hours after reperfusion. Twelve hours after reperfusion, necrosis extended throughout the ischemic kidney; nearly all of the tubular epithelial cells were destroyed. At 3 to 12 hours after reperfusion, CysLT1R expression gradually became weaker on endothelial cells. At 24 hours after reperfusion, CysLT1R expression was almost at the level of that in nonischemic kidney. Expression of CysLT1R was noted in a rat model of renal I/R injury. Several hours after the maximal CysLT1R expression, we observed the maximum renal I/R injury. These results may suggest a relationship between the CysLT1R and renal I/R injury.

A recent increase in AIDS at Lyon University Hospitals: patient characteristics and comparisons with previous years.

BACKGROUND: A 36% increase in the incidence of AIDS was observed in 2002/2003 compared with 2000/2001 at Lyon University Hospitals. OBJECTIVES: We compared the characteristics of these patients with the characteristics of those diagnosed previously with AIDS. METHODS: Data for all patients with AIDS diagnosed at Lyon University Hospitals were analyzed. The data were collected prospectively. Multiple logistic regression was used for analysis. RESULTS: The variables independently associated with an AIDS diagnosis in 2002/2003 compared with the 1985-1989 period were: homosexual exposure [odds ratio (OR) 0.4; 95% confidence interval (CI) 0.2-0.8]; heterosexual exposure in an endemic area (OR 22.5; 95% CI 6.8-74.8), compared with other exposure to HIV; lymphoma as initial AIDS event (OR 10.3; 95% CI 2.7-39.1) compared with Pneumocystis carinii pneumonia; and age at first AIDS event aged 34-38 years (OR 2.5; 95% CI 1.0-6.4), aged 39-46 years (OR 5.1; 95% CI 2.2-11.8), and aged 47-84 years (OR 10.6; 95% CI 4.5-25.1) compared with aged <30 years. The variables independently associated with an AIDS diagnosis in 2002/2003 compared with the 1997/2001 period were age at first AIDS event aged 34-38 years (OR 0.4; 95% CI 0.2-0.9) compared with aged <30 years. CONCLUSION: Recently diagnosed AIDS patients differed from those diagnosed previously, showing an epidemic switch in different populations. The characteristics of the AIDS population in 2002/2003 might reflect public health messages disseminated around 10 years ago or more for the prevention of HIV transmission. Anticipation of populations affected by the AIDS epidemic is difficult.

[Kaposi's sarcoma and organ transplantation: 22 cases]. / Maladie de Kaposi et transplantation d'organes: 22 cas.

BACKGROUND: The discovery of the Human Herpes virus 8 (HHV8) improved our knowledge of the pathogenesis of Kaposi's sarcoma. After organ transplantation, Kaposi's sarcoma exhibits distinctive features compared with other forms of the disease. PATIENTS AND METHODS: We report 22 cases of post-transplant Kaposi's sarcoma (12 kidneys, 2 kidney-pancreas, 6 livers and 2 hearts). The aim of this retrospective study was to analyze clinical and virological characteristics in these transplant patients and to specify the frequency of HHV8 seroconversions in this population. RESULTS: Twenty-one patients showed cutaneous lesions and 9 had visceral involvement. HHV8 serology was positive in 16/20 patients at transplantation and in 21/22 cases at the time of Kaposi's sarcoma diagnosis. Most cases corresponded to viral reactivations whereas seroconversions occurred in 2 cases and may have been linked to viral transmission by the graft. Treatment led to recovery in 68p. 100 of the cases. Two heart-transplant patients died from their disease. We included in our series two cases of re-transplanted patients without recurrence of Kaposi's sarcoma and one case of familial Kaposi's sarcoma. DISCUSSION: Seroconversions after transplantation emphasize the interest of systematic screening of HHV8 serology in transplant recipients and their donors.

Induction of transplantation tolerance in humans using fetal cell transplants.

When engrafted with donor stem cells and lymphoid cells, patients develop transplantation tolerance to donor antigens. We analyzed the mechanism of tolerance induction in immunoincompetent recipients whose immunity has been reconstituted by transplantation of mismatched stem cells. Seven infants or human fetuses received fetal liver transplants as a treatment for severe combined immunodeficiency disease. After reconstitution of immunity by lymphocytes developed from donor stem cells, T-cell clones were produced and analyzed. Because donors and recipients were HLA mismatched, it was easy to demonstrate the donor origin of the T-cell clones. These clones were shown to have developed tolerance to histocompatibility antigens of the stem cell donor via a process of clonal deletion (probably as a result of contact with donor-derived macrophages and dendritic cells). They were also tolerant to histocompatibility antigens of the host but through a different mechanism: many clones recognized these antigens but had no detrimental effect on the target cells exhibiting host antigens, either in vitro or in vivo. Clonal anergy was therefore the cause of this tolerance to host determinants, resulting in a lack of graft-versus-host disease and of autoimmunity. The contact between developing T cells of donor origin and host epithelial cells within the host thymus may explain this colonal anergy. It should be noted that all patients had high serum levels of interleukin-10, which might have contributed to the persistent engraftment and tolerance.

Human interleukin-10 transduced fetal liver stem cells prolong survival of mouse skin and heart allografts.

Interleukin (IL)-10 regulates immune responses, acting as a suppressive cytokine by inhibiting the synthesis of Th1 cytokines, such as IL-2 and interferon (IFN)-gamma. It also strongly down-regulates major histocompatibility complex (MHC) class II determinants on antigen presenting cells (APC). On the other hand, long-term tolerance is well correlated with the persistence of a peripheral microchimerism. In this study, we investigated the synergistic effect of human IL-10 (huIL-10) and hematopoietic microchimerism for the induction of long-term tolerance. Irradiated Balb/c mice (H-2d) were used as recipients (fetal liver stem cells [FLSC], skin and heart) and C57BL/6 (H-2b) mice were used as donors of FLSC, skin and heart. Recipients were simultaneously transplanted with the heart, the skin and with huIL-10 gene-transduced FLSC. Microchimerism was checked using fluorescent flow cytometry, huIL10 production using enzyme-linked immunosorbent assay (ELISA), and graft survival was evaluated by daily observation. Significant level of huIL10 (up to 900 pg/mL) was detected for more than 2 weeks in the serum of mice that underwent transplantation. Four weeks after the FLSC injection, microchimerism was identified in the recipient lymphoid organs (spleen, thymus, and bone marrow) by the presence of donor cells (H-2b). Finally, in the group of mice treated with huIL-10 gene-transduced FLSC, skin allografts survived for 18.9 +/- 1.8 days compared with 9.5 and 9.6 days in the groups of mice treated with nontransduced FLSC or huIL-10 alone, respectively. The same pattern for heart allograft survival was observed. HuIL-10 transduction of donor hematopoietic stem cells resulted in production of huIL-10, cell engraftment, and chimerism. Although full tolerance was not obtained, specific and highly significant (P < .001) prolongation of the survival of donor heart allografts with (more than 2-fold compared with nontreated groups) was observed. The infiltration of the transplanted heart and its late rejection demonstrate that stem cells transduced with huIL-10 gene induce "prope" tolerance in this model.

Characteristics of patients diagnosed with AIDS shortly after first detection of HIV antibodies in Lyon University hospitals from 1985 to 2001.

A diagnosis of AIDS shortly after the detection of HIV antibodies suggests a long-lasting course of the disease without care. The factors associated with a short delay between the initial HIV-1-positive test and the first AIDS-defining event were identified in 1901 patients from 1985 to 2001 in Lyon University hospitals. A total of 576 individuals (30.3%) had an interval of /=60 years (OR 4.5; 95% CI 2.5-8.1), compared to those<30 years old; heterosexuality (OR 2.4; 95% CI 1.6-3.4); injection drug use (OR 2.1; 95% CI 1.5-2.7); and other exposures (OR 2.4; 95% CI 1.6-3.4), compared to homosexual exposure; two opportunistic infections at AIDS (OR 1.8; 95% CI 1.4-2.4) compared to one; and Pneumocystis carinii pneumonia as initial AIDS event (OR 2.6; 95% CI 1.8-3.7), compared to Kaposi's sarcoma. These results provide opportunities to refocus local public health interventions to reduce delayed access to care.

The AIDS epidemic in Lyon: patient characteristics and defining illnesses between 1985 and 2000.

OBJECTIVES: To define the characteristics of 1899 patients diagnosed with AIDS at Lyon University Hospitals (LUH) across four time periods corresponding to different antiretroviral eras, and to analyse the evolution of specific AIDS-defining illnesses (ADIs) with time. METHODS: All AIDS patients at LUH between 1 January 1985 and 31 December 2000 were included in the study. The data were compared using the chi(2) test and one-way analysis of variance. RESULTS: The absolute number of new AIDS cases increased by 30.3% between 1985 and 1995 but decreased by 26.5% between 1996 and 2000. The proportion of women with AIDS increased significantly (P<0.001) and mean age at diagnosis also increased significantly over time (P<0.001). The proportion of infection through heterosexual contact increased dramatically, while that through homo/bisexual intercourse or injection drug use (IDU) decreased significantly (P<0.001). The absolute number of ADIs declined with the introduction of highly active antiretroviral therapies (HAART) (P<10(-6)). Pneumocystis carinii pneumonia remained the leading ADI in 1996-2000 (23.3%). A significant increase in the proportion of non-Hodgkin's lymphoma (NHL) was observed over time (P<10(-5)) but the number of new NHL cases decreased during HIV infection after 1996. CONCLUSIONS: The decline in the incidence of AIDS with the advent of HAART was confirmed in our hospital cohort. The gradual increase in the proportion of NHL among ADIs underscores the long latency period between infection with HIV and the achievement of an effect of HAART on HIV-associated lymphomagenesis.

Bicêtre hospital experience with sirolimus-based therapy in human renal transplantation: the Sirolimus European Renal Transplant Study.

In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n = 42) or sirolimus (n = 41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. At 12 months, graft survival (98% sirolimus vs 93% CsA), patient survival (100% vs 98%), and incidence of biopsy-confirmed acute rejection (41% vs 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P

Efficacy of mycophenolate mofetil on recurrent glomerulonephritis after renal transplantation.

Recurrent glomerulonephritis in transplanted kidneys is not rare despite classical immunosuppressive drugs and depends on the etiology of nephropathy. Treatment of recurrence of renal disease on graft remains controversial. We report 6 cases of patients with recurrent glomerulonephritis after renal transplantation treated with mycophenolate mofetil (MMF). The glomerular diseases were Wegener's granulomatosis (n = 1), membranoproliferative glomerulonephritis type I (n = 1), focal and segmental glomerular sclerosis (n = 1), membranous glomerulonephritis (idiopathic membranous nephropathy (n = 1) and systemic lupus erythematous) (n = 1)) and immunoglobulin A nephropathy (n = 1). MMF was introduced because of intolerance of classical immunosuppressive treatment in 2 cases and because of its inefficiency in the other cases. MMF was introduced between 3 months and 36 months (13.5 +/- 7 months) after recurrence of the primitive glomerulonephritis. During combined MMF/cyclosporine/prednisone therapy, only 3 patients responded to MMF. MMF was disrupted precociously in 1 out of 3 patients who stabilized renal function because of discovery of lung cancer and in 2 out of the 3 other patients because of gastrointestinal intolerance and severe anemia. We supposed that MMF could represent a new effective alternative therapy of recurrent glomerulonephritis on renal graft in some cases.

Multiple sclerosis-associated retrovirus particles cause T lymphocyte-dependent death with brain hemorrhage in humanized SCID mice model.

A retroviral element (multiple sclerosis-associated retrovirus, MSRV) defining a family of genetically inherited endogenous retroviruses (human endogenous retrovirus type W, HERV-W) has been characterized in cell cultures from patients with multiple sclerosis. Recently, MSRV retroviral particles or the envelope recombinant protein were shown to display superantigen activity in vitro, but no animal model has yet been set up for studying the pathogenicity of this retrovirus. In the present study, the pathogenicity of different sources of MSRV retroviral particles has been evaluated in a hybrid animal model: severe combined immunodeficiency (SCID) mice grafted with human lymphocytes and injected intraperitoneally with MSRV virion or mock controls. MSRV-injected mice presented with acute neurological symptoms and died within 5 to 10 days post injection. Necropsy revealed disseminated and major brain hemorrhages, whereas control animals did not show abnormalities (P <.001). In ill animals, reverse transcriptase-polymerase chain reaction (RT-PCR) analyses showed circulating MSRV RNA in serum, whereas overexpression of proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma was evidenced in spleen RNA. Neuropathological examination confirmed that hemorrhages occurred prior to death in multifocal areas of brain parenchyma and meninges. Further series addressed the question of immune-mediated pathogenicity, by inoculating virion to SCID mice grafted with total and T lymphocyte-depleted cells in parallel: dramatic and statistically significant reduction in the number of affected mice was observed in T-depleted series (P <.001). This in vivo study suggests that MSRV retroviral particles from MS cultures have potent immunopathogenic properties mediated by T cells compatible with the previously reported superantigen activity in vitro, which appear to be mediated by an overexpression of proinflammatory cytokines.

Treatment of post-transplant lymphomas with anti-B-cell monoclonal antibodies.

The treatment of post-transplant lymphomas still needs major improvements in order to put the patient in remission and to retain graft function. Chemotherapy is far too toxic in these patients. A more specific treatment such as anti-B-cell monoclonal antibody is very promising. The cytotoxic effect of antibody relies mainly on complement-induced and antibody-dependent cellular cytotoxicity; apoptosis may also induce tumor cell death. B-cell antigens expressed on the cell surface are the targets of antibody attack; some specificities may be chosen because of their level of expression or because of signaling induced within the cell. Anti-B-cell antibodies can be produced by genetic engineering in order to be humanized or to carry bispecific Fabs. The efficacy and safety of anti-B-cell monoclonal antibodies (mAbs) in transplant patients have been proven with different antibodies such as anti-CD21/CD24 mAb, anti-CD38 mAb and anti-CD20 mAb. In a retrospective analysis of different centers in France, rituximab (anti-CD20 mAb, Roche Products) achieved an overall 69% remission rate in 34 organ and bone-marrow transplant patients. But the conditions of use of antibody must be better defined, particularly with regard to the immunosuppressive therapy, the type of tumor and the dose of antibody. We must also improve our understanding of the in vivo mechanisms of action of antibody to develop more efficient antibody constructs.

Induction versus noninduction in renal transplant recipients with tacrolimus-based immunosuppression.

BACKGROUND: The aim of this study was to compare the efficacy and safety of induction treatment with antithymocyte globulins (ATG) followed by tacrolimus therapy with immediate tacrolimus therapy in renal transplant recipients. METHODS: This 12-month, open, prospective study was conducted in 15 centers in France and 1 center in Belgium; 309 patients were randomized to receive either induction therapy with ATG (n=151) followed by initiation of tacrolimus on day 9 or immediate tacrolimus-based triple therapy (n=158). In both study arms, the initial daily tacrolimus dose was 0.2 mg/kg. Steroid boluses were given in the first 2 days and tapered thereafter from 20 mg/day to 5 mg/day. Azathioprine was administered at 1-2 mg/kg per day. RESULTS: At month 12, biopsy-confirmed acute rejections were reported for 15.2% (induction) and 30.4% (noninduction) of patients (P=0.001). The incidence of steroid-sensitive acute rejections was 7.9% (induction) and 22.2% (noninduction)(P=0.001). Steroid-resistant acute rejections were reported for 8.6% (induction) and 8.9% (noninduction) of patients. A total of nine patients died. Patient survival and graft survival at month 12 was similar in both treatment groups (97.4% vs. 96.8% and 92.1% vs. 91.1%, respectively). Statistically significant differences in the incidence of adverse events were found for cytomegalovirus (CMV) infection (induction, 32.5% vs. noninduction, 19.0%, P=0.009), leukopenia (37.3% vs. 9.5%, P<0.001), fever (25.2% vs. 10.1%, P=0.001), herpes simplex (17.9% vs. 5.7%, P=0.001), and thrombocytopenia (11.3% vs. 3.2%, P=0.007). In the induction group, serum sickness was observed in 10.6% of patients. The incidence of new onset diabetes mellitus was 3.4% (induction) and 4.5% (noninduction). CONCLUSION: Low incidences of acute rejection were found in both treatment arms. Induction treatment with ATG has the advantage of a lower incidence of acute rejection, but it significantly increases adverse events, particularly CMV infection.

Gene transfer of anti-gp41 antibody and CD4 immunoadhesin strongly reduces the HIV-1 load in humanized severe combined immunodeficient mice.

OBJECTIVE: To study the anti-HIV-1 effects of the delivery of anti-gp41 monoclonal antibody (mAb) and soluble CD4 (sCD4) immunoadhesin by genetically modified cells in HIV-1-infected, humanized severe combined immunodeficient (SCID) mice. DESIGN: The complementary DNA of mAb 2F5, an anti-HIV-1 gp41 antibody, and of sCD4-IgG chimeric immunoadhesin were transferred into 3T3 cells using Moloney murine leukaemia virus vectors. The cells were then incorporated into a collagen structure called the neo-organ, which allowed the continuous production of the therapeutic molecules. METHODS: The antiviral effects in vivo of 2F5 or sCD4-IgG or both compounds were evaluated in neo-organ-implanted SCID mice that were grafted with human CD4 CEM T cells and challenged with HIV-1 Lai or MN. RESULTS: In SCID mice implanted with 2F5 neo-organs, antibody plasma levels reached 500-2000 ng/ml. Viral loads after HIV-1 challenge were significantly reduced in neo-organ-implanted HIV-infected mice. Although 29 x 10(7) and 13 x 10(8) HIV-1-RNA copies/ml were detected at 12 days in the controls (mice injected with Lai and MN, respectively) less than 16.5 x 10(3) HIV-1-RNA copies/ml were observed in all implanted mice injected with either Lai or MN. The intracellular viral load was also reduced in CD4 cells recovered from the implanted mice. Comparable antiviral effects were obtained with CD4-IgG neo-organs. CONCLUSION: Our results confirm the anti-HIV properties of 2F5 and sCD4-IgG continuously produced in vivo after ex-vivo gene therapy in SCID mice.

Perinatal fetal-cell and gene therapy.

Several inherited diseases can now be treated using postnatal or prenatal, in utero, transplantation of stem cells from the human fetal liver. Twenty-four patients with severe immunodeficiency diseases have been treated in infancy and three at the fetal stage, in our institution. We have also treated similarly 34 patients with inborn errors of metabolism or hemoglobinopathies. A total of 64% of all patients are alive with either full cure of their initial disease or at least significant benefit from the treatment. Immunological reconstitution can develop despite full mismatch between the stem cell donor and the recipient patient. Tolerance is acquired both towards donor and host antigens. Gene therapy is starting its development in some infants with an immunodeficiency related to a known gene defect and, in the future, it may be used in fetuses, immediately after the prenatal diagnosis of the gene abnormality.

Oligo-monoclonal immunoglobulins frequently develop during concurrent cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections in patients after renal transplantation.

In the present study we report that the appearance of oligo-monoclonal immunoglobulins (oligoM-Igs) in the sera of transplanted individuals is concurrent with the detection of coincident active CMV infection and EBV replication. Eighty-four renal allograft patients were monitored with respect to CMV isolation, to CMV conventional serology and humoral response against the EBV trans-activator ZEBRA (an immediate-early antigen also called BZLF1). Titration of anti-ZEBRA antibodies (IgG and IgM) and amount of EBV DNA in serum were evaluated. Using the combination of four techniques (agarose gel electrophoresis, analytical isoelectric focusing, high resolution immunoelectrophoresis, immunofixation electrophoresis), oligoM-Igs were found in 25% of patients after allografting and significantly associated with rejection episodes (P < 0.001). Twenty out of 23 (86%) concurrent CMV/EBV infections were associated with serum oligoM-Igs (P < 0.001). One can thus reasonably assume that a sustained EBV replication following iatrogenic immunosuppression can promote the immunoglobulin heavy chain expression in EBV-infected B lymphocytes. The proliferation of immunoglobulin-secreting clones might occur after active CMV infection, through a transient over-immunosuppression or via immune subversion.

Interleukin-10 in Epstein-Barr virus-associated post-transplant lymphomas.

We used enzyme-linked immunosorbent assays (ELISA) to investigate the presence of interleukin-10 (IL-10) in the serum of patients developing post-transplant lymphomas. Serum IL-10 was detected in 14 out of 19 cases with a lymphoma or Hodgkin's disease, with higher values being observed in patients who had developed a lymphoma within the first few months post-transplantation, and who had an aggressive form of the disease. Eleven out of the 14 patients in whom IL-10 was detected had Epstein Barr virus-positive tumors. And 11 out of 14 patients died of lymphomas. In most of the patients who had detectable IL-10 at the time of diagnosis of the lymphoma, the IL-10 had not been present previously, but it was found in the serum of 7 out of 9 dialysis patients, and in 8 out of 17 stable transplant patients. We conclude that IL-10 plays a role in the development of the more severe forms of post-transplant lymphomas, and may be secreted by tumor cells. However. data from patients with chronic renal failure or patients undergoing immunosuppressive therapy must be treated with caution.