Post-transplant reactivation of hepatitis C virus: lymphocyte infiltration and the expression of adhesion molecules and their ligands in liver allografts

Hepatitis C virus (HCV) recurrence after liver transplantation has been associated with chronic rejection. Biopsies from 10 patients with post-transplant HCV were examined for expression of adhesion molecules ICAM-1, VCAM-1, and ELAM-1, number of lymphocytes positive for their ligands LFA-1, VLA-4, and SLeX, and activation markers MHC class II antigens and IL2-R by immunohistochemistry. The phenotypes of the graft-infiltrating lymphocytes were determined. Results were compared to those for patients with normal graft function or rejection. Five recipients with HCV reactivation and one with de novo HCV had a biopsy available showing induction of ICAM-1 in sinusoidal endothelium (p<0.05) and hepatocytes (p<0.01), and Class II antigens in hepatocytes (p<0.01), compared to normal controls. Lymphocytes in the graft infiltrate expressed LFA-1, VLA-4, and Class II antigens, but IL2-R was not significantly expressed. CD3+, CD4+, and CD8+ cells were observed. In our study, HCV recurrence was not associated with acute or chronic rejection, and the inflammation was due to the viral infection.     

Midbrain binding of [123I]nor-beta-CIT in atypical depression

BACKGROUND: Altered serotonin (SERT) and dopamine transporter (DAT) densities have been recorded in major depression. Atypical depression (ATD) has been suggested to be connected to decreased serotonergic transmission, but no studies have been published on the association between brain serotonin transporter density and ATD. METHODS: PATIENTS with depression (n=29) were divided into three groups according to DSM-IV criteria: atypically depressed, melancholic patients, and "undifferentiated" patients. Depressive symptoms were evaluated with the 29-item Hamilton Depression Rating Scale (HAM-D-29). Single photon emission computed tomography (SPECT) with [(123)I]nor-beta-CIT was used to evaluate serotonin transporter density (SERT) in the midbrain and dopamine transporter density (DAT) in the striatum of patients and healthy controls (n=18). RESULTS: All subgroups except those with undifferentiated depression had lower SERT densities compared to controls. No significant differences were found in the densities between the subgroups. Atypical scores of HAM-D-29 were associated with SERT densities in the midbrain (beta=-0.40, t=-2.3, p=0.03), even after adjustment for age, gender and HAM-D-21 scores (beta=-0.39, t=-2.32, p=0.03). CONCLUSIONS: The association between atypical scores of HAM-D-29 and midbrain SERT densities suggests a relationship between serotonergic dysfunction and ATD.     

Monitoring of viral load by quantitative plasma PCR during active cytomegalovirus infection of individual liver transplant patients

A quantitative PCR test, the Cobas Amplicor CMV Monitor, was used for the monitoring of viral load in the peripheral blood of 27 individual liver transplant patients and correlated with cytomegalovirus (CMV) pp65 antigenemia. Altogether, 243 specimens were analyzed. During the first 3 months, 20 patients showed PCR positivity which correlated with pp65 antigenemia. Of those, 13 patients developed symptomatic CMV infection 27 to 52 days after transplantation, with a significantly higher peak viral load in PCR and in pp65 assay compared with the seven asymptomatic infections (median 10,200 versus 2,240 copies/ml, P < 0.05, and median 100 versus 30 pp65-positive cells/50,000 leukocytes, P < 0.01). Five were primary infections of D+/R- cases (donor CMV seropositive and recipient seronegative) and demonstrated, except in one case, a high peak viral load (>10,000 copies/ml; range, 10,200 to 21,600 copies, and > or =50 positive cells, range, 50 to 800 cells). The peak viral loads of the six D+/R+ patients with symptomatic infection varied widely (range, 2,290 to 126,000 copies and 50 to 300 positive cells). Two D-/R+ patients developed symptomatic infection with a lower viral load (range, 1,120 to 6,510 copies and 25 to 100 positive cells). All symptomatic infections were successfully treated with ganciclovir. The asymptomatic infections all in D+/R+ patients with low copy numbers (<5,500 copies) were monitored until CMV disappeared. One of the seven PCR-negative patients had one sample with low antigenemia, but the subsequent specimens were all negative. The time-related correlation of the two methods was also good. In summary, quantitative PCR could equally well be used as the CMV pp65 assay for the monitoring of viral load in individual transplant patients.     

Persistent cytomegalovirus infection in kidney allografts is associated with inferior graft function and survival

The long-term effects of cytomegalovirus (CMV) infections on kidney allografts are unknown. We examined the impact of persistent intragraft CMV infection on long-term kidney allograft function and survival. CMV was diagnosed in 82/172 renal transplant recipients by antigenemia test and viral cultures. Biopsies from 48 of 82 patients taken after CMV infection and from 15 patients with no previous CMV infection detected were available for the immunohistochemical demonstration of CMV antigens and DNA hybridization in situ. Five-year follow-up data from these 63 patients were analysed. In 17 patients, CMV antigens and/or DNA persisted in the biopsy >2 months after the last positive finding in blood or urine. Patients with persistent intragraft CMV had reduced graft survival (P = 0.041) and Cox regression analysis showed persistent CMV as a risk factor for reduced graft survival (RR: 3.5). Recipients with persistent intragraft CMV had reduced creatinine clearance 1 and 2 years after transplantation (P = 0.007) and in multivariate logistic regression analyses including several potential pre- and posttransplant risk factors, persistent CMV was an independent risk factor for lower clearance at 1 and 2 years (OR: 4.4 and 4.9). Our novel findings show that persistent intragraft CMV infection was associated with reduced kidney allograft function and survival.     

Measuring implementation progress in kangaroo mother care

Aim: To describe the development and testing of a monitoring model with quantitative indicators or progress markers that could measure the progress of individual hospitals in the implementation of kangaroo mother care (KMC). Methods: Three qualitative data sets in the larger research programme on the implementation of KMC of the MRC Research Unit for Maternal and Infant Health Care Strategies in South Africa were used to develop a progress-monitoring model and an accompanying instrument. Results: The model was conceptualized around three phases (pre-implementation, implementation and institutionalization) and six constructs depicting progress (awareness, adopting the concept, mobilization of resources, evidence of practice, evidence of routine and integration, sustainable practice). For each construct, indicators were developed for which data could be collected by means of the monitoring instrument used in a walk-through visit to a hospital. The instrument has been tested in 65 hospitals.

Conclusion: The progress-monitoring model enables the quantification of individual hospitals' progress in the process of implementing KMC and an objective measurement of the effectiveness of different outreach strategies. The model also has potential to be adapted for measuring progress in other innovative healthcare interventions on a large scale.     

Characterization of colonic and mesenteric lymph node dendritic cell subpopulations in a murine adoptive transfer model of inflammatory bowel disease

Ulcerative colitis and Crohn's disease, collectively termed inflammatory bowel diseases (IBD), are chronic inflammatory diseases of the intestine that afflict more than 4 million people worldwide. Intestinal inflammation is characterized by an abnormal mucosal immune response to normally harmless antigens in the gut flora. In Crohn's disease, the pathogenic mucosal immune response is a typical T helper (TH1) type cell response, whereas ulcerative colitis is predominantly associated with a TH2 response. We are interested in the role of dendritic cells in early immunologic events leading to T cell activation and chronic intestinal inflammation. Using a murine adoptive transfer model of IBD, we found an accumulation of dendritic cells in colon and mesenteric lymph nodes during the early stage of IBD before the appearance of epithelial lesions and tissue degradation. In situ immunostaining and flow-cytometric analysis revealed that approximately 50% of colonic dendritic cells were CD11b B220 myeloid dendritic cells and 50% expressed the CD11b B220 plasmacytoid phenotype. In corresponding mesenteric lymph nodes, approximately 16% were plasmacytoid dendritic cells. Colonic myeloid dendritic cells were shown to express the co-stimulatory molecule CD40. Both, colonic myeloid and plasmacytoid dendritic cells released interferon-alpha in situ and stimulated T cell proliferation ex vivo. Our results show that dendritic cells can mature in the intestine without migrating to mesenteric lymph nodes. Mature intestinal dendritic cells may form a nucleation site for a local T cell response and play an important role in the pathogenesis of IBD.     

The impact of cytomegalovirus infections and acute rejection episodes on the development of vascular changes in 6-month protocol biopsy specimens of cadaveric kidney allograft recipients

BACKGROUND: The role of cytomegalovirus (CMV) in chronic kidney allograft rejection remains controversial. The purpose of this study was to examine the impact of CMV infection on histopathologic changes in 6-month protocol biopsy specimens of kidney allografts. METHODS: Altogether, 52 renal allograft recipients were studied. CMV infection was diagnosed by CMV antigenemia test, viral cultures from blood and urine, or both. CMV was demonstrated in the biopsy specimens by antigen detection and hybridization in situ. Acute rejections were diagnosed by biopsy histology, and biopsy specimens were graded according to the Banff '97 classification. RESULTS: CMV infection was diagnosed in 41 patients. The 11 patients in whom CMV infection was not detected were used as controls. Acute rejection was diagnosed in 22 of 41 CMV patients and in 6 of 11 control patients. CMV was demonstrated in the biopsy specimens of 19 of 41 CMV patients. CMV was not associated with increased glomerular, tubular, or interstitial changes. However, the arteriosclerotic changes in small arterioles were significantly increased in the subgroup of patients where CMV was demonstrated in the graft as compared with controls (P<0.01). Analysis of the impact of acute rejection on arteriolar thickening showed that only a positive history of both acute rejection and CMV found in the graft was associated with significantly increased vascular changes compared with CMV-free recipients (P<0.05). CONCLUSIONS: Neither CMV nor acute rejection alone was associated with increased vascular or other histopathologic changes in 6-month protocol biopsy specimens of kidney allografts, but a previous history of both acute rejection and the presence of CMV in the graft was associated with increased vascular changes.     

Pretransplant human herpesvirus 6 infection of patients with acute liver failure is a risk factor for posttransplant human herpesvirus 6 infection of the liver

BACKGROUND: Acute liver failure (ALF) is a significant cause of liver transplantation. We have previously reported that human herpesvirus-6 (HHV-6) was found in most livers of patients with ALF of unknown origin ending up with liver transplantation. In this study, we investigated the posttransplant HHV-6 infection of the liver graft in these patients. METHODS: Thirty-two patients transplanted due to ALF were included in this retrospective study. Twelve of the 15 patients with unknown cause and four of 17 patients with a known cause of ALF had HHV-6 antigens in the explanted liver. Altogether, 18 patients had some pretransplant evidence of HHV-6. After transplantation, the patients were frequently monitored for the viruses, and biopsy histology was performed in every case of graft dysfunction. HHV-6 was demonstrated in liver tissue by immunohistochemistry. RESULTS: During the follow-up of 6 months, hepatic HHV-6 infection was demonstrated in 9 of the 18 patients, at a mean 19 days (6-38 days) after transplantation. All patients with posttransplant HHV-6 showed graft dysfunction. In biopsy histology, seven out of these nine patients demonstrated viral infection, one of them also having CMV antigens in the liver. None of those patients without evidence of pretransplant HHV-6 showed HHV-6 in the posttransplant biopsies. Posttransplant HHV-6 was not treated and the virus had no effect on 1-year patient or graft survivals. CONCLUSION: Pretransplant hepatic HHV-6 infection of patients with ALF is a risk factor for posttransplant HHV-6 infection and liver dysfunction, but has no effect on 1-year graft or patient survival.     

Effects of transforming growth factor-beta and formula feeding on systemic immune responses to dietary beta-lactoglobulin in allergy-prone rats

Early nutritional events have the potential to affect health outcomes in later life including the development of allergy. Food allergy is usually the first manifestation of allergy. Breast-feeding has been associated with a protective effect against the development of allergy, but the evidence is contradictory and the mechanisms involved are not clear. We hypothesize that milk cytokines, such as transforming growth factor beta (TGF-beta), play a role in regulating immune responses to dietary antigens. Using a rat pup model of gastrostomy feeding, the immune response profile, at weaning and post-weaning, of allergy-prone Brown Norway rats fed formula supplementation with TGF-beta was assessed. We show that feeding formula to allergy-prone rat pups results in increased total IgE immunoglobulin, beta-lactoglobulin (BLG) IgG1 antibody, and mucosal mast cell activation, as measured by serum rat mast cell protease II (RMCPII) levels in the gut. Supplementation of formula with physiological levels of TGF-beta down-regulated the BLG IgG1 response as well as total IgE and mucosal mast cell activation. Supplementation of formula also resulted in an increase in Th1 cytokines, interleukin (IL)-18, IL-12p40, IL-12p35, and interferon gamma (IFN-gamma) and an increase in IL-10. In conclusion, TGF-beta supplementation of formula moved the immune response profile of allergy prone (Th2 type) rat pups toward a Th1 profile in the suckling period. Importantly, this immune profile persisted after weaning when TGF-beta was no longer present in the diet.