Hepatitis C virus (HCV) persistence in the host results from inefficiencies of innate and adaptive immune responses. Most studies addressing the role of innate immunity concentrated on peripheral blood (PB) natural killer (NK) cells, whereas only limited information is available on intrahepatic (IH) NK cells. We therefore examined phenotypic and functional features of IH and PB NK cells in paired liver biopsy and venous blood samples from 70 patients with chronic HCV infection and 26 control persons subjected to cholecystectomy for gallstones as controls. Ex vivo isolated IH NK cells from HCV‐infected patients displayed unique phenotypic features, including increased expression of NKp46‐activating receptor in the face of reduced tumor necrosis factor–related apoptosis‐inducing ligand (TRAIL) and cluster of differentiation (CD) 107a expression, which resulted in impaired degranulation compared with controls. To gain insights into the effect of HCV on NK cells, we exposed peripheral blood mononuclear cells (PBMCs) from patients and healthy donors to cell‐culture–derived HCV (HCVcc) and measured NK cell degranulation, TRAIL, and phosphorylated extracellular signal‐regulated kinase 1/2 (pERK1/2) expression. Exposure of PBMCs to HCVcc significantly boosted NK degranulation, pERK1/2, and TRAIL expression in healthy donors, but not in patients with chronic HCV infection, a defect that was completely reversed by interferon‐alpha. Purified NK cells showed a minimal, though significant, increase in degranulation and TRAIL expression, both in patients and controls, after exposure to HCVcc. Conclusions: These findings indicate dysfunctional IH NK cell cytotoxicity associated with TRAIL down‐regulation in chronic HCV infection, which may contribute to virus persistence. PB NK cell impairment upon exposure to HCVcc suggests the existence of an accessory cell‐dependent NK cell lytic defect in chronic HCV infection predominantly involving the TRAIL pathway. (HEPATOLOGY 2012;56:841–849)
The new immunosuppressive drug FK 506 was used from the outset with low doses of prednisone to treat 120 recipients of primary liver grafts and 20 more patients undergoing liver retransplantation. The patient survival rate after 2 to 8 months in the primary liver transplantation series is 93,3%, with original graft survival of 87.5%. Of the 20 patients in the hepatic retransplant series, 17 (85%) are living. Almost all of the surviving patients have good liver function. In addition 11 hearts, 2 double lungs, and a heart-lung have been transplanted under .FK 506, with survival of all 14 patients. With all of the organ systems so far tested, including the kidney (which has been reported elsewhere), rejection usually has been controlled without additional drugs and with lower average steroid doses than in the past. Nephrotoxicity has been observed, but not to an alarming degree, and there has been a notable absence of hypertension. There is a suggestion that serum cholesterol may be lowered by FK 506, but this is unproved. Although the adverse reactions of FK 506 and the immunosuppressive mechanisms resemble those of cycIosporine, our preliminary observations suggest that FK 506 may have a more advantageous therapeutic index.
The experimental immunosuppressive drug FK 506 was given to 36 renal transplant recipients, many of whom were highly sensitized. Ten were undergoing kidney retransplantation, 10 also underwent liver transplantation at an earlier time (6 patients) or concomitantly (4 patients), and 2 patients received a third organ (heart or pancreas) in addition to a liver and kidney. With follow-ups of 4 to 13 months, all but 2 of the 36 patients are alive, 29 (81 %) are dialysis 'free, and most have good renal function. Twenty of the 29 dialysis-free patients are receiving no or low-dose (2.5 to 5.0 mg/d) prednisone therapy. Only one kidney was lost to cellular rejection. However, patients who had antidonor cytotoxic antibodies in current or historical serum samples had a high rate (3 of 9) of irreversible humoral rejection. A low incidence of posttransplant hypertension was noteworthy. Hirsutism and gingival hyperplasia were not observed. Serum cholesterol levels in patients who took FK 506 were unexpectedly low, and the effect on the level of uric acid was minimal. The side effects of FK 506 therapy include nephrotoxicity, neurotoxicity, and potential induction of a diabetic state. These are similar to the side effects of cyclosporine use, but probably less severe. The seeming safety, efficacy, and relative freedom from side effects of FK 506 encourage further trials in kidney transplantation.
Oral preoperative CHO load is effective for avoiding a blood glucose level >180 mg/dL, but without affecting the risk of postoperative infectious complication.
The effect of conversion from cyclosporine-steroid immunosuppression to the new agent FK506 was studied in 96 liver allograft recipients who were experiencing graft dysfunction or cyclosporine toxicity. Patients were stratified according to the cause of graft dysfunction that ultimately led to conversion to FK506. Response to FK506 introduction was monitored pathologically and biochemically. The outcome of a switch from CsA to FK506 was highly favorable in patients experiencing acute and the early stages of chronic rejection, despite optimal conventional therapy. Patients with later stages of chronic rejection did not respond to conversion to FK506 and most eventually lost their liver grafts in this process. Patients in whom we had difficulty separating chronic rejection from chronic persistent or low-grade chronic active hepatitis were mostly unaffected by conversion to FK506. Active hepatitis was a poor indication for conversion, because most of the patients experienced graft failure or died from liver failure. As a group, there was no statistically significant change in renal function 180 days after conversion to FK506. These findings expand the experience with FK506 in human liver allograft recipients.
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