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C Legendre

Publications and source records attributed to C Legendre.

At least 181 records · Page 10Linked to original sources
PubMed1991

Differential in situ expression of cytokines in renal allograft rejection.

The expression of the interleukin 6, tumor necrosis factor alpha, and interferon gamma (IFN-gamma) genes was studied in human renal biopsies from individuals without evidence of kidney disease and from patients undergoing acute renal allograft rejection using a method of in situ hybridization capable of detecting 1-5 copies of a specific cellular messenger RNA in individual cells. IL-6, TNF-alpha, and IFN-gamma RNA transcripts were not detected in any of the sections of normal human kidneys. Elevated levels of IL-6 mRNA but not IFN-gamma were, however, detected in the sections of the renal biopsies from six of eight patients exhibiting acute rejection. A uniform level of expression of IL-6 mRNA was observed in all the cells examined, including glomerular cells, tubular epithelia, smooth muscle cells, and vascular endothelia, as well as the interstitial mononuclear infiltrate. Juxtatabular clusters of TNF-alpha mRNA were detected in the absence of IL-6 mRNA in one patient exhibiting acute rejection. Only a small number of grains (1-5 per high-power field) was detected in the urinary space or in the tubular or vascular lumen following hybridization with the IL-6 or TNF-alpha probes. In contrast, in kidney transplant patients with stable renal function no significant labeling was observed with the IL-6, TNF-alpha, or IFN-gamma probes. A similar level of expression of actin mRNA was observed in all the sections of normal and transplanted kidneys studied, suggesting that the overall level of RNA synthesis was similar in both groups. These results suggest that cytokines such as IL-6 play a role in acute allograft rejection.

Cytokines↗
PubMed1991

MR imaging of renal transplant rejection.

The results of 62 consecutive MR examinations were correlated with the subsequent clinical course and histologic results. Twenty-six cases of rejection showed a marked diminution of cortico-medullary differentiation (CMD). The renal parenchymal vascular pattern and visibility of renal sinus fat were not markedly altered in rejection and there was no difference between normal and rejected allograft shape. The ability of MR imaging to diagnose renal transplant rejection is only based on CMD, which, however, is non-specific. In 2 cases of severe acute rejection, T2 weighted images showed an abnormal signal intensity of the cortex due to renal infarction. Our preliminary results in 8 patients with Gd-DOTA injection showed 2 cases with necrosis seen as areas with absent contrast enhancement. This technique seems to be promising in the detection of perfusion defects.

Adult↗
PubMed1990

Chronic hepatitis in kidney allograft recipients.

98 HBsAg-positive and 31 HBsAg-negative kidney recipients were compared to assess the effect of renal transplantation on chronic liver disease and vice versa. Diagnosis was based on analysis of liver biopsy specimens including semiquantitative evaluation of histological features of chronic hepatitis. Serial specimens were examined: chronic liver disease occurred in 88% of HBsAg-positive patients and 4% of HBsAg-negative patients with normal liver at the time of transplantation. Liver abnormalities in the former were chronic persistent hepatitis (32%), chronic active hepatitis (51%), and cirrhosis (17%). Actuarial patient survival was similar in HBsAg-positive (78%) and HBsAg-negative (87%) patients, as was allograft survival (64% and 71%, respectively). In both HBsAg-positive and HBsAg-negative patients chronic alcohol consumption was more frequent in those with chronic liver disease than those without. These data suggest that renal transplantation may be appropriate for haemodialysis patients with chronic hepatitis whatever their HBV status.

Actuarial Analysis↗
PubMed1990

Genetic basis of nonresponse to hepatitis B vaccine in hemodialyzed patients.

Genetic factors are implicated in the response of normal subjects to hepatitis B vaccine. The aim of our study was to investigate if HLA Class I and II proteins could participate in a nonresponse to this vaccine in immunocompromised, namely hemodialyzed, patients. One hundred and seven hemodialyzed patients (68 men and 39 women, mean age 35 years) were vaccinated with Pasteur Hevac B vaccine, with a mean delay of 2 months following the onset of chronic hemodialysis. Patients were considered nonresponders when their serum antiHBs remained less than 10 mUI/ml on at least two occasions within the 12 months following the vaccination. HLA-A, B and DR antigens were determined by complement-dependent microlymphotoxicity. Ninety patients (84%) were responders and 17 (16%) nonresponders. The HLA-A1, B8 and DR3 frequency was higher in nonresponders (35, 35 and 44%, respectively) than in responders (18, 4 and 14%, respectively). The extended haplotype HLA-A1, B8, DR3 was more frequent in the former (19%) than in the latter (2%) (p less than 0.03). There was only one female within the nonresponders (6%) as compared to 37 (41%) in the responders (p less than 0.05). We conclude that genetic determinants (sex and HLA markers) play a critical role in the induction of an antiHBs immune response in both immunoincompetent hemodialyzed patients and normal immunocompetent hosts.

Adolescent↗
PubMed1990

In vivo cell activation following OKT3 administration. Systemic cytokine release and modulation by corticosteroids.

A massive and self-limited release of tumor necrosis factor and interferon gamma was detected in the systemic circulation in 35 consecutive renal allograft recipients by specific radioimmunoassays very soon following the first injection of the monoclonal antibody OKT3 (anti-CD3). Peak serum TNF and IFN gamma levels were reached, respectively, at 1 and 4 hr following the first OKT3 injection. Abnormally high serum interleukin 2 levels were also observed 4 hr following the first OKT3 injection in a minority of patients (5 cases). OKT3 had no effect on interleukin 1 beta, interferon alpha, and granulocyte/macrophage colony stimulating factor serum levels, which in all patients remained within the normal range throughout the study. This selective OKT3-induced cytokine release, which only followed the first injection, was transient (i.e., lasting a few hours). It tightly paralleled the spontaneously reversible clinical syndrome characterized by high fever, headaches, and gastrointestinal symptoms that is invariably associated with the first OKT3 administration. Importantly, when administered in adequate dosages and with adequate timing, corticosteroids influenced both the cytokine release and the systemic reaction. Thus, the highest TNF, IFN gamma, and IL-2 serum levels were detected in patients who did not receive corticosteroids. Patients who received high-dose corticosteroids (1 g solumedrol bolus) concomitantly with the first OKT3 injection still had high TNF and IFN gamma levels. Conversely, when the same corticosteroid dose was injected 15-60 min prior to the first OKT3 injection, in all cases the increase of serum TNF and IFN gamma was significantly lower as compared with the above-described groups; IL-2 levels did not rise. These data offer a direct explanation for one major side effect of OKT3 and thus provide the basis for devising means to prevent its occurrence.

Antibodies, Monoclonal↗
PubMed1990

[Hepatocyte transplantation. Treatment of hepatic encephalopathy. An experimental study in the rat].

The aim of this work was to assess the effect of intrasplenic liver cell transplantation (ILCT) on hepatic insufficiency induced by a terminolateral portocaval shunt (PCS) in rats. Thirty syngenic Wistar Furth rats were divided up into three groups: (a) rats with PCS (n = 10); (b) rats with PCS then ILCT of 10(7) liver cells isolated from the livers of syngenic rats (n = 10); (c) operated control rats (n = 10). Double-blind behavior tests were carried out two weeks, two months and six months after surgery. The spontaneous motor activity and the exploring activity of each rat were studied in automated cages fitted with infrared diodes. Each interruption of the infrared beam was automatically recorded by a computer and converted into an activity score (number/hour). The spontaneous motor activity and the exploring activity were poor in the rats with PCS. The ILCT significantly increased the spontaneous motor activity and the exploring activity 2 months and 3 weeks after transplantation, respectively. Three months after transplantation, the spontaneous motor activity and the exploring activity in the PCS/ILCT group were not significantly different from those of the control rats. This study shows that ILCT can correct the neurological signs of hepatic encephalopathy in an experimental model of chronic hepatic insufficiency, and suggests that ILCT may produce therapeutic benefits in chronic hepatic insufficiency.

Animals↗
PubMed1990

The OKT3 immunosuppressive effect. In situ antigenic modulation of human graft-infiltrating T cells.

OKT3 exerts its in vivo immunosuppressive effects by inducing major peripheral T cell depletion as well as antigenic modulation of the T3/Ti T cell receptor complex. Modulated cells, which reversibly lose the expression of the CD3 T cell receptor molecular complex but still share the CD4 and CD8 antigens, have been shown to be functionally immunoincompetent. Antigenic modulation is maintained as long as significant OKT3 serum levels are present. Cells infiltrating renal allografts from seven OKT3 treated patients were studied by double immunofluorescence to assess whether antigenic modulation could affect cells located in profound organs such as renal allografts. Needle biopsies were obtained in patients given OKT3 (5 mg/day) for at least 10 consecutive days in association with conventional immunosuppressive drugs for treatment of a rejection episode (5 cases) or prophylactically (2 cases). In all patients at the time of biopsy, CD3 positive cells were absent from the circulation, significant OKT3 serum levels were present, and neither IgG nor IgM anti-OKT3 antibodies were detected. Infiltrating cells were double-labeled using a combination of either anti-CD3 and anti-CD4 or anti-CD3 and anti-CD8 monoclonal antibodies. Following 7-14 consecutive days of treatment, all patients given OKT3 for a rejection episode showed a significant decrease in the number of graft-infiltrating lymphocytes. Importantly, all T cells still infiltrating the allograft were CD3-CD4+ or CD3-CD8+ cells, which is exactly the same phenotypical pattern of CD3 circulating modulated T cells. In 6 out of the 7 patients, this phenotypical pattern was associated with clinically normal graft function. These results further underline the fact that antigenic modulation is an important mechanism mediating the immunosuppressive effect of OKT3 both in peripheral blood and in renal allografts.

Antibodies, Monoclonal↗
PubMed1989

Hypertension in kidney transplantation.

The prevalence of hypertension is approximately 50 percent in renal transplanted patients, even in the most recent series. Hypertension contributes to the cardiovascular complication observed in these patients. Hypertension is related to various mechanisms: renin release from the own remaining kidney(s), stenosis of the transplant artery, often chronic rejection, rarely recurrence of the initial disease on the renal graft, or possibly transmission of "predisposition" to essential hypertension with the graft.

Humans↗
PubMed1989

Characteristics of clometacin-induced hepatitis with special reference to the presence of anti-actin cable antibodies.

The clinical, biochemical, histopathological and immunological features of 30 cases of clometacin-induced hepatitis are described. The age range of the patients was 32-84 years with a notable female predominance of 29:1. The hepatitis was highly cytolytic with high values of transaminases but with little or no cholestasis. Gammaglobulins were higher than 18 g/l in 73% of the cases. 25 liver biopsies were performed and showed acute hepatitis with a predominant centrilobular necrosis in 17; chronic aggressive hepatitis was noted in 8 cases but 1 showed concomitant cirrhotic changes. Anti-tissue antibodies were looked for in all cases. Anti-smooth muscle antibodies of anti-actin cable type (titre 1/80 to 1/2, 560) were detected in 19 cases, anti-nucleus antibodies in 16 cases which were associated to the former in 14 cases. The above findings show that clometacin produces a hepatitis syndrome quite akin to autoimmune chronic active hepatitis (lupoid hepatitis) and to the hepatopathy induced by oxyphenisatin.

Actins↗