Biomedical subjects
Publications and source records attributed to B Charpentier.
This article reports a case of arteriocaliceal fistula following a kidney transplant biopsy. Hematuria and anuria were arrested by therapeutic embolic occlusion.
In several combinations of inbred rats, liver allografts are spontaneously tolerated, and after a few weeks liver tolerant rats are in a state of donor-specific transplantation tolerance. In vivo and in vitro experiments were conducted to analyze the immunological status of LEW or BN rats with spontaneously tolerated (LEW X BN) F1 liver allografts several months after transplantation. Acute rejection of secondary donor-specific heart allografts retransplanted from liver-tolerant rats to normal syngeneic hosts suggests that the state of tolerance in liver-tolerant rats is related to an active modification of the immune system of the rat and not to a reduced immunogenicity of the graft. No cytotoxic antibodies or cells were found in liver-tolerant rats. Reactivity in mixed lymphocyte culture was normal or slightly reduced. Arguments for the presence of splenic suppressor cells were found in LEW tolerant rats using a local graft-versus-host assay, but these could not be found in BN rats, or when attempting to transfer or to break the tolerance state. A nonspecific humoral blocking factor was found in vitro in liver-tolerant rats but transfer of serum from liver-tolerant rats to normal syngeneic hosts did not permit a significant prolongation of donor-specific heart allografts. These results suggest that more than one mechanism may be involved at the maintenance phase of liver allograft tolerance.
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Five focal non typhoid salmonellosis (NTS) are reported in a group of 342 kidney transplant recipients. There is no relationship between the unusual presentation of NTS (septicemia, pneumonia, orchitis, prostatis, urinary tract infections) and the serotypes (S. typhi-murium, S. panama). With the therapeutic immunodepression, many host factors are important to induce the unusual presentation of NTS: major surgery, urologic abnormalities, preexisting uraemic state. The major importance of decreased host resistance is emphasized by the absence of relationship between death and bacterial resistance. The use of lysotypes exclude the role of an intrahospital contamination.
Kidneys of potential donors undergoing sudden cardiac arrest are generally not gathered because the warm ischemia time is too long until nephrectomy. A rapid in situ cold perfusion technique was developed to preserve kidneys in 21 brain-dead patients after cardiac arrest not responding to cardiac resuscitation. In 7 of the 21 potential donors, the in situ perfusion was unsuccessful. In 14 other subjects this technique permitted to save 15 transplantable kidneys; 1 month after grafting, the renal function was similar to that observed in kidneys gathered in living patients. The in situ perfusion technique allows to increase by nearly 10% the efficacy of kidney gathering.
Since lymphocyte radiolabeling is widely used for in vitro and in vivo studies and may interfere with the properties of the cells, the purpose of this work was to investigate the effects of 99mTc labeling on lymphocyte morphology and functions. Two ranges of 99mTc activity were used, 37 and 370 MBq, and their effects were compared to those produced by a graduated external irradiation. Electron microscopy was performed and T cells were studied using biological markers (E-Rosette formation, cell proliferation under lectin reactivity, and specific cell-mediated cytolysis). After 370-MBq labeling, an intense cytotoxic effect was observed on cell morphology, drastically impeding T-lymphocyte functions. Thirty-seven-megabecquerel labeling and sham procedure did not significantly affect cell functions. The external irradiation dose-response curve indicated a clear radiation-induced inhibitory effect, especially over 10 Gy. This effect was less intense than that obtained with 370-MBq 99mTc labeling. The labeling cytotoxic effect can then be attributed to a radiolesion due to a radiation dose which is probably higher than 10 Gy. In fact, the dose received by lymphocytes during the 370-MBq labeling procedure was estimated as 70 Gy by calculations, taking into account all emissions of 99mTc.
The cytotoxic capacities of T lymphocytes and natural killer (NK) cells and the phagocytic functions of polymorphonuclear leukocytes were determined in a group of 20 patients with end stage disease who were being maintained on hemodialysis. The mononuclear cells from these patients were able to mediate normal T-cytotoxic functions in a xenogeneic cell-mediated lympholysis assay and normal NK cytotoxic capacity when tested against K562 target cells. Contrarily, polymorphonuclear functions in these patients were severely impaired. The reduction of Nitroblue tetrazolium in dark formazan (NBT test) and the direct phagocytosis of 2 pyogenic strains (Staphylococcus aureus and Salmonella typhimurium) were equally and deeply depressed in almost all patients. This defect was not restored either by 4 hr of hemodialysis nor by 12 months of treatment. This study confirms a major role for a defect of polymorphonuclear cell functions in the depressed defence of patients on chronic hemodialysis against infections.
The authors describe five cases of renal allograft rupture as a result of acute rejection. In one case of perineal hematoma, no operation was performed. The evolution of the hematoma led to a periureteral sclerosis, which was successfully operated. The authors advocate deferring the surgical management of allograft ruptures. Once the diagnosis has been established with the aid of physical examination, electrography and computerized scanography, the extra time can be devoted to following the evolution of the rejection. If the rejection is irreversible, a nephrectomy has to be performed, but if it is reversible, they favour conservative treatment followed by operative intervention around the tenth day.
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A collaborative study including seven kidney transplant centers in Paris recorded 19 new cases of "de novo" membranous glomerulonephritis (MGN) in a series of 1000 kidney graft biopsies over 1550 renal transplantations. This study represents the largest series "de novo" MGN in the literature. The mean time for the onset of the proteinuria was 26 months post-transplantation (extremes 2-58 months). None of the following factors seemed to be linked with the presence of MGN: age, sex, donor-recipient HLA phenotype, 1st graft vs 2nd graft, cadaver vs related graft, HLA matching, recipient treatment, number of transfused blood units, lymphocytotoxins, number of rejection episodes, number and length of acute tubular necrosis, viral or bacterial infections. These 19 new cases of MGN were compared to the other previously published 42 cases. They generally do not appear to be deleterious for the graft function.
Cimetidine, an H2-receptor antagonist had no immunoproliferative or immunostimulative effect on in vitro T cell functions of normal human peripheral blood lymphocytes. This was shown by adding Cimetidine to mitogen, alloantigen and xenoantigen-stimulated cultures. Generation of helper and cytotoxic T cells was not modified in a full kinetic experiment. These data failed to confirm previous reports showing an increase of cell-mediated immunity under Cimetidine therapy.
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125I-labeled human beta 2 microglobulin forms complexes with Rat serum glycoproteins. After beta 2m injection in vivo, the serum contains a complex in a 55 K-67 K position. When incubated with Rat serum vitro beta 2m forms additional complexes in greater than or equal to 200 K position. The 55 K complex is partially precipitated by Brown-Norway anti-Lewis alloantiserum.
T-cells were investigated by the E rosette assay, PHA stimulation, allogeneic MLC and CML responses, in a group of 100 healthy aged people over 70 years old, and compared to young control individuals less than 45 years old. No major difference was found between the two groups, except for PHA stimulation which was significantly reduced in old individuals when low mitogen concentration was used. These observations suggest that only some T cells subsets are affected by ageing, without modification of the total T lymphocyte number. Contrarily, the phagocytic activities of polymorphonuclear cells assessed in a group of 38 aged people were dramatically decreased, using either the NBT test or a direct phagocytosis assay.
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