Evolution of fibrosis during HCV recurrence after liver transplantation--influence of IL-28B SNP and response to peg-IFN and ribavirin treatment.

The IL-28 gene is associated with sustained viral response (SVR) after treatment with peg-IFN and ribavirin in liver transplant recipients with chronic hepatitis C genotype 1 infection. We analysed the importance of recipient and donor IL-28B genotype for response to treatment and fibrosis progression in 54 liver transplant recipients. Fibrosis stage (F) was defined as mild when F≤2 and severe when F≥3 in a liver biopsy or according to liver elasticity analysis. We found a significantly lower prevalence of IL-28B SNP CC in the recipients (22%) than in the donors (67%), P<0.0001. SVR was seen in 61% of the recipients with mild and 27% with severe fibrosis pretreatment, P=0.01. Recipients with IL-28 CC and non-CC had mild fibrosis in 64% and 38% prior to treatment, P=0.13. At follow-up, after treatment, significantly more recipients with CC had mild fibrosis than non-CC recipients (75% versus 32%, P=0.0072), and all with CC and SVR had mild fibrosis. The strongest baseline factor predicting SVR was genotype. Hence, 13/19 (68%) genotype non-1 patients reached SVR versus only 9/35 (26%) genotype 1 patients, P=0.0022. In summary, we found that liver transplant recipients with IL-28B CC tended to have less advanced fibrosis prior to and significantly less after SOC treatment and that all recipients with IL-28B CC who achieved SVR had mild fibrosis at follow-up. A significantly higher SVR rate was achieved in recipients with mild than severe fibrosis pretreatment and with genotype non-1 than 1 infection. Our findings indicate that treatment for post-transplant HCV recurrence should be offered before advanced fibrosis is seen in the recipient.

Concentration-guided ribavirin dosing with darbepoetin support and peg-IFN alfa-2a for treatment of hepatitis C recurrence after liver transplantation.

Relapse of hepatitis C virus infection after liver transplantation is universal. Standard-of-care (SOC) treatment for relapse offers less satisfactory treatment response than in nontransplanted patients. Tolerance for treatment is suboptimal and withdrawals owing to adverse events induced by treatment frequent. To improve tolerance for SOC, and ribavirin (RBV) in particular, concentration-guided RBV dosing calculated by a formula taking renal function and weight into consideration was utilized. A serum RBV concentration of 10 µm was set as the goal. All patients were given maintenance darbepoetin therapy from 2 weeks prior to initiation of treatment. In total, 21 patients with a mean age of 52 (range 25-64) years were included. The mean RBV concentration at week 4 was 10.2 and 7.36 µm in genotype 1/4 and non-1/4 patients, respectively, and 11.7 and 9.42 at week 12. The mean haemoglobin drop was 25 g/L vs 21 g/L in the genotype 1/4 and non-1/4 group, respectively, a nonsignificant difference. With this treatment approach, 80-90% of patients could be kept adherent to treatment. Sustained viral response was achieved 8/16 (50%) with low-grade fibrosis (fibrosis stage ≤ 2) vs in none of five patients with advanced fibrosis (Fibrosis stage 3 and 4), P < 0.05. We conclude that a treatment algorithm utilizing concentration-guided RBV dosing during darbepoetin maintenance therapy substantially improves tolerance and allows high adherence to a SOC treatment schedule, and that therapy needs to be initiated before advanced fibrosis is developed.

Liver transplantation for familial amyloidotic polyneuropathy (FAP): a single-center experience over 16 years.

Orthotopic liver transplantation (LTx) is currently the only available treatment that has been proven to halt the progress of familial amyloidotic polyneuropathy (FAP). The aim of this study was to assess mortality and symptomatic response to LTx for FAP. All 86 FAP patients transplanted at our hospital between April 1990 and November 2005 were included in the study. Five patients underwent retransplantation. The 1-, 3- and 5-year patient survival rates in patients transplanted during 1996-2005 were 94.6%, 92.3% and 92.3%, respectively, a significant difference from the rates of 76.7%, 66.7% and 66.7%, respectively, during 1990-1995 (p = 0.0003). Multivariate analysis revealed that the age at the time of LTx (>or=40 years), duration of the disease (>or=7 years) and modified body mass index (mBMI) (<600) were independent prognostic factors for patient survival. A halt in the progress of symptoms was noted in most patients, but only a minority experienced an improvement after LTx. To optimize the posttransplant prognosis, LTx should be performed in the early stages of the disease, and close post-LTx monitoring of heart function by echocardiography and of heart arrhythmia by Holter ECG is mandatory.

Parameters obtained by hepatobiliary scintigraphy have significant correlation with biochemical factors early after liver transplantation.

BACKGROUND: Early postoperative hepatobiliary scintigraphy after liver transplantation is performed worldwide, but data on its significance for graft function are currently limited. PURPOSE: To examine the correlation between the result of early postoperative hepatobiliary scintigraphy and pre- and postoperative biochemical parameters in liver transplantation (LTx) patients. MATERIAL AND METHODS: Six parameters of hepatobiliary scintigraphy using (99m)Tc mebrofenin were statistically analyzed in 108 LTx patients: 1) half-life of the activity of elimination of mebrofenin from the blood; 2) total clearance of mebrofenin from the blood due to all possible routes; 3) half-life of the activity due to liver uptake; 4) clearance of mebrofenin from the blood due to liver uptake; 5) time to maximal uptake in the liver; and 6) the hepatic extraction fraction (HEF) and biochemical data. Analysis between patients with preoperative normal liver function, familial amyloid polyneuropathy (FAP), and end-stage liver disease (non-FAP) was also performed. RESULTS: Univariate and multivariate analysis revealed that total bilirubin postoperative day 3 correlated with all three scintigraphic parameters, and peak aspartate aminotransferase and alanine aminotransferase correlated with HEF. The analysis between patients with FAP and non-FAP revealed no significant difference of scintigraphic data between the two groups. CONCLUSION: A significant correlation between early postoperative scintigraphic results and biochemical parameters was demonstrated.

Introduction of hand-assisted retroperitoneoscopic living donor nephrectomy at Karolinska University Hospital Huddinge.

Living donor kidney transplantation accounts for about 50% of the total number of renal transplantations at our center. From 1999 through 2005, 75 out of 220 living donor nephrectomies were performed with a laparoscopic technique (LLDN). In June 2005, we introduced the technique of hand-assisted retroperitoneoscopic nephrectomy (HARS) for living donors. Since the introduction until the end of 2005, 11 out of 18 living donor nephrectomies (LDN) were performed with HARS. Reduced operation time was observed for the HARS group (mean, 166 minutes) compared with the LLDN (mean, 244 minutes). Two grafts showed delayed function, one in the LLND group and one in the HARS group. No major perioperative or postoperative complications were observed in the HARS group, whereas one patient who underwent LLDN developed severe pancreatitis. So far in our hands HARS is a fast and safe procedure with results comparable with open LDN. Compared to LLDN, we experienced reduced operation time together with the advantage of retroperitoneal access.

Liver transplantation for HCV cirrhosis at Karolinska University Hospital Huddinge, Stockholm.

Hepatitis C virus (HCV)-induced cirrhosis is the major indication for liver transplantation globally, and an increasing indication for liver transplantation in Sweden. We have retrospectively examined the 120 patients transplanted for HCV cirrhosis from 1987 through 2005, including 11 who received more than one graft. The 1-, 3-, and 5-year postoperative survivals for all patients transplanted for HCV with or without hepatocellular cancer (HCC) were 77%, 66%, and 53%, respectively. HCV patients without HCC had a 1-, 3-, and 5-year survivals of 78%, 73%, and 61%, compared with 84%, 79% and 74%, respectively, for patients transplanted with chronic liver diseases without cancer or HCV. The number of patients with HCV cirrhosis transplanted in our center is increasing. Compared with patients transplanted for other chronic liver diseases, we experienced inferior results among patients with HCV cirrhosis.

Binding of peptides from the N-terminal region of alpha-gliadin to the celiac disease-associated HLA-DQ2 molecule assessed in biochemical and T cell assays.

Celiac disease (CD) is most probably an immunological disease, precipitated in susceptible individuals by ingestion of wheat gliadin and related proteins from other cereals. The disease shows a strong HLA association predominantly to the cis- or trans-encoded HLA-DQ(alpha1*0501, beta1*02) (i.e., DQ2) heterodimer. T cell recognition of gliadin peptides presented by DQ2 in the intestinal mucosa is central in the immunopathogenesis of CD. Here we describe a study where overlapping peptides from the N-terminal region of alpha-gliadin have been tested in biochemical assays for binding to affinity-purified DQ2 and DR3 (i.e., DR(alpha, beta1*0301)) molecules. The peptides were also tested for binding to DQ2 in a functional binding assay, where binding was measured as the capacity to inhibit the stimulation of a gliadin-specific, DQ2-restricted T lymphocyte clone RNnTalpha33. In both assay systems the overlapping gliadin peptides were found to bind with weak or intermediate affinity to DQ2. No or only very weak binding was found to DR3 in the biochemical binding assay. Overall, the results question the role of these peptides in the T-cell-mediated immunopathogenesis of CD. The in vitro assays described here provide new methods for the screening of potentially toxic peptides.

Gluten activation of peripheral blood T cells induces a Th0-like cytokine pattern in both coeliac patients and controls.

Coeliac disease is apparently a T cell-mediated disease, precipitated in the proximal small intestine of susceptible individuals by gluten. Preferential presentation of gluten peptides most probably takes place in coeliac mucosa by the disease-associated HLA-DQ2 and -DQ8 molecules. In peripheral blood, however, both HLA-DR, -DQ and -DP-restricted T cell responses to gluten have been observed. We examined gluten-specific T cell clones (TCC) derived from peripheral blood for cytokine production to see if their profiles were related to the HLA restriction or the disease state of the donors. As previously found for mucosal TCC, the main product was interferon-gamma (IFN-gamma), often with additional IL-4, IL-5, IL-6, IL-10, tumour necrosis factor, and transforming growth factor-beta. Regardless of restriction element or disease state, gluten-reactive TCC from peripheral blood therefore seem to secrete cytokines compatible with a Th0 profile.

HLA-DQ2-restricted T-cell recognition of gluten-derived peptides in celiac disease. Influence of amino acid substitutions in the membrane distal domain of DQ beta 1*0201.

CD is precipitated in susceptible individuals by ingestion of wheat gluten. The disease is strongly associated to the HLA-DQ(alpha 1*0501, beta 1*0201) (DQ2) heterodimer, where both the DQ alpha and DQ beta chains are required for susceptibility. We have recently shown that gluten-specific CD4+ T cells from the small intestinal mucosa of CD patients are predominantly restricted by the CD-associated HLA-DQ(alpha 1*0501, beta 1*0201) heterodimer. Here we report studies on the influence of aa substitutions in the DQ beta 1*0201 chain on DQ2-restricted T-cell recognition of gluten antigens. A B-LCL expressing the DQ(alpha 1*501, beta 1*0301) heterodimer was transfected with the DQB1*0201 gene, or with DQB1*0201 genes altered by site-directed mutagenesis. Surface expression of the wild-type or mutated DQ(alpha 1*0501, beta 1*0201) heterodimers was observed in the transfectants. Seven DQ2-restricted, gluten-specific TCCs were then investigated with respect to their ability to recognize antigen presented by the transfectants. All TCCs were sensitive to one or more of the aa substitutions induced but showed different response patterns. The results demonstrate that single aa substitutions of the DQ beta 1*0201 chain at positions in the peptide-binding cleft of DQ(alpha 1*0501, beta 1*0201) may affect binding of gluten-derived peptides and/or interfere with T-cell recognition. Because all seven TCCs studied were differently affected, they probably differ with respect to glutenpeptide and/or DQ(alpha 1*0501, beta 1*0201) restriction fine specificity.

T cells from the peripheral blood of coeliac disease patients recognize gluten antigens when presented by HLA-DR, -DQ, or -DP molecules.

Coeliac disease (CD) is a T-cell mediated immunological disease of the small intestine which is precipitated in susceptible individuals by ingestion of gluten. We recently reported that gliadin-specific T cells can be found in the small intestinal mucosa of CD patients, and that a preponderance of these T cells was restricted by the CD-associated DQ(alpha 1*0501,beta 1*0201) heterodimer. Here we report studies on whether the same is found for gliadin specific T cells in the peripheral blood of CD patients. T-cell responses towards gluten antigens in vitro were found for both most CD patients and healthy controls. Gluten-specific T-cell clones (TCC) were established from four CD patients. Although a large proportion of these TCC were restricted by DQ molecules, including the CD-associated DQ(alpha 1*0501,beta 1*0201) heterodimer, several were restricted instead by DR or DP molecules. Thus, gluten-derived peptides can be presented to T cells by several different HLA class-II molecules, and the preferential DQ(alpha 1*0501,beta 1*0201) restriction of gluten-specific T cells in the small intestinal mucosa of CD patients is less pronounced than for similar T cells in the peripheral blood.

T cells recognize a peptide derived from alpha-gliadin presented by the celiac disease-associated HLA-DQ (alpha 1*0501, beta 1*0201) heterodimer.

CD is unique among the HLA-associated diseases since (a) the disease-promoting agent (gliadin) is known and (b) the disease is precipitated mainly in individuals carrying a particular cis- or trans-encoded HLA-DQ heterodimer; i.e., DQ(alpha 1*0501, beta 1*0201). Further, a preponderance of gliadin-specific T cells derived from the small intestinal mucosa of CD patients are restricted by this DQ heterodimer. T-cell recognition of gliadin peptides presented by the DQ(alpha 1*0501, beta 1*0201) heterodimer may thus be of importance in CD. Here we report that a T-cell clone from a patient with CD recognizes a synthetic alpha-gliadin peptide, when presented by the cis- or trans-encoded CD-associated DQ(alpha 1*0501, beta 1*0201) heterodimer. The minimal peptide recognized by the T-cell clone corresponds to residues 31-47 of alpha-gliadin, which is included in the part of alpha-gliadin previously shown to have disease-promoting activity. When testing analogue peptides derived from other alpha-gliadin sequences, one peptide differing by one amino acid was recognized by the T-cell clone, whereas the other peptide differing by two amino acids was not recognized. Our findings demonstrate that the CD-associated DQ(alpha 1*0501, beta 1*0201) heterodimer may serve as an antigen-presenting molecule to T cells for certain gliadin peptides.

Wheat peptide challenge in coeliac disease.

The exact nature of the cereal moiety that exacerbates coeliac disease is unknown. In-vitro studies have implicated both the N-terminal and far C-terminal domains of one of the wheat prolamins, A-gliadin. Peptides within these regions may act as epitopes that trigger immune events leading to enteropathy. We synthesized three peptides corresponding to amino-acids 3-21, 31-49, and 202-220 of A-gliadin. Four patients with coeliac disease were challenged by intraduodenal infusion of 1 g of gliadin or 200 mg of the synthetic peptides. Jejunal biopsies were taken before and at hourly intervals for 6 h after the infusion. Morphometric variables were measured and intraepithelial lymphocytes counted. Significant histological changes occurred in the small intestinal mucosa after challenge with a synthetic peptide corresponding to amino acids 31-49 of A-gliadin. The N-terminal peptide, residues 3-21 of A-gliadin, did not cause histological changes in any of the patients. In one of the four patients, minor histological changes following challenge with the peptide corresponding to residues 202-220 of A-gliadin were seen. Our results suggest that the oligopeptide corresponding to aminoacids 31-49 of A-gliadin is toxic in vivo, but there is no evidence of toxicity of the far N-terminal peptide, residues 3-21. The C-terminal peptide 202-220 may contain an epitope to which patients with coeliac disease display variable sensitivity. Since the oligopeptide corresponding to amino-acids 31-49 of A-gliadin is recognised by HLA DQ2-restricted T cells, the observed effects may be due to immune activation within the intestinal mucosa.

T cells specific for viral antigens presented by HLA-Dw4 recognize DR13 on allogeneic cells: a possible mechanism for induction of rejection.

Alloreactivity probably involves T cell recognition of peptides bound to allogeneic HLA molecules. In order to study whether T cells recognizing common viral antigens presented by self HLA molecules also recognize some allogeneic HLA molecules we generated T lymphocyte clones (TLC) specific for herpes simplex virus (HSV) antigen. Two TLC were found which recognized HSV presented by self Dw4, but which also respond to DR13 on allogeneic cells in the absence of HSV. The response against DR13 could be inhibited by preincubating the allogeneic cells with tetanus toxoid, but not with other protein antigens tested. The difference between Dw4 (encoded by DRB1*0401) and DR13 (encoded by DRB1*1302) mainly involves amino acid residues assumed to be of importance for peptide binding, and not residues putatively interacting with the T cell receptor. Thus, the results suggest that T cells recognizing a virally-derived peptide presented by self Dw4 molecules may also recognize a different peptide presented by allogeneic DR13 molecules. Our findings indicate that some rejection episodes may be induced and effected by T cells activated by viral peptides presented by self HLA molecules.

Insulin dependent diabetes mellitus susceptibility or protection may be determined by certain HLA-DQ molecules.

On the basis of our own studies and those of others, we suggest that several DQ molecules may be involved in IDDM susceptibility (Table 2). Our studies suggest that these DQ molecules may be encoded both when the DQA1 and DQB1 genes are in cis or trans position. A common denominator of several of these IDDM susceptibility molecules is that they have a non-Asp amino acid at DQ beta chain residue 57. Our studies demonstrate that this residue may be an important residue for peptide presentation to T cells.

Particular HLA-DQ alpha beta heterodimer associated with IDDM susceptibility in both DR4-DQw4 Japanese and DR4-DQw8/DRw8-DQw4 whites.

Insulin-dependent diabetes mellitus (IDDM) susceptibility is associated with the DR4-DQw4 haplotype in Japanese and the DR4-DQw8/-Drw8-DQw4 genotype (among others) in whites. We investigated whether these Japanese and white individuals encode the same or a similar DQ alpha beta heterodimer, which may be an IDDM-susceptibility molecule in both populations. First, we carried out genomic DQA1 and DQB1 typing with sequence-specific oligonucleotide probes. The results revealed that Japanese DR4-DQw4 and white DR4-DQw8/DRw8-DQw4 IDDM patients carried the DQA1*0301 allele and the DQB1*0401 or DQB1*0402 allele, either in the cis (Japanese DR4-DQw4 individuals) or trans (white DR4-DQw8/DRw8-DQw4 individuals) position. Because the DQB1*0401 and DQB1*0402 alleles differ only at residue 23, these DQB1 genes are very similar. We next tested cells from these individuals with a particular DQ-specific T-lymphocyte clone, HH58. The clone was only restimulated with cells from Japanese individuals who carried the DQA1*0301 and DQB1*0401 alleles in the cis position or white individuals who carried the DQA1*0301 and DQB1*0402 alleles in the trans position. Thus, particular cis- or trans-encoded DQ alpha beta heterodimers, which in both cases are recognized by T lymphocytes, may confer susceptibility to IDDM in both ethnic groups.

T cells recognizing an HLA-DQ alpha beta heterodimer encoded in cis by the DR4DQw4 haplotype and in trans by DR4DQw8/DRw8DQw4 heterozygous cells.

We generated alloreactive DQ-specific CD4+ T-lymphocyte clones. One of these (TLC HH58) was only restimulated with cells having the DR4DQw4 haplotype or cells being DR4DQw8/DRw8DQw4 heterozygous. The former cells carry the DQA1*0301 and DQB1*0401 alleles in cis position while the latter cells carry DQA1*0301 and DQB1*0402 alleles (DQB1*0402 is identical to DQB1*0401 except for codon 23) in trans position. Thus, very similar DQ alpha beta heterodimers are encoded by these genes in both cis and trans positions, which are recognized by the same T cells.