Search results for "VIRUS DISEASE"
showing 10 items of 1907 documents
Role of inflammation and infection in vascular disease
2006
Relationship of infection, inflammation, and atherosclerosis has been a subject of intensive investigation in recent years. Potential mechanisms whereby chronic infections may play a role in atherogenesis are myriad. Chlamydia pneumoniae (Cp) infection in early life may accelerate atherosclerosis, leading to cardiovascular complications. Other infections, simultaneously occurring with Cp, may result in a synergistic effect to promote atherosclerosis. Chronic Helicobacter pylori infection is known to increase the pH level of the gastric juice and to decrease ascorbic acid levels, both of which will lead to a reduced folate absorption. Low folate hampers the methionine synthase reaction. This…
Human cytomegalovirus (HCMV)-specific CD4+ T lymphocyte response in AIDS patients with no past or current HCMV disease following HAART.
2003
Abstract Background: The incidence of Human Cytomegalovirus (HCMV) end-organ disease has dramatically decreased since the implementation of highly active antiretroviral therapies (HAARTs), but the precise immune mechanism whereby HCMV is controlled remains to be elucidated. Objectives: To investigate the effect of (HAART) on CD4 + T-cell immunity to HCMV in AIDS patients with no past or current HCMV disease. Study design: Seventeen patients were prospectively examined for CD4 + (CD45RO + and CD45 RA + ) T-cell counts (flow cytometry), HIV RNA load (Amplicor HIV test), HCMV leukoDNAemia and HCMV DNA in urine (nested PCR), lymphoproliferative response (LPR) to HCMV, phytohemagglutinin (PHA) a…
Assessment of human cytomegalovirus specific T cell immunity in human immunodeficiency virus infected patients in different disease stages following …
2004
T cell immunity to human cytomegalovirus (HCMV) was assessed in HAART-treated HIV-1 infected patients (9 asymptomatic, CDC group A; and 22 symptomatic, CDC group B), and in eight HIV-1 long term non-progressors. Patients were either prospectively or cross-sectionally examined for CD4(+) T cell counts, HIV RNA load, HCMV leukoDNAemia, HCMV DNA in urine, lymphoproliferative response (LPR) to HCMV and phytohemagglutinin (PHA), and cytokine secretion (IFN-gamma and IL-4) by HCMV-stimulated peripheral blood mononuclear cell (PBMC) cultures. No patient either progressed to clinical AIDS or developed HCMV active infection during the study period. Twenty-nine patients responded to HAART, though 12 …
Virological and immunological features of active cytomegalovirus infection in nonimmunosuppressed patients in a surgical and trauma intensive care un…
2010
Cytomegalovirus (CMV) reactivation occurs frequently in critically ill patients. The natural course of CMV infection and the interaction between CMV and the adaptive immune system in this setting remain poorly defined. Fifty-three CMV-seropositive patients in a surgical and trauma intensive care unit were included in this study. The CMV DNA load in tracheal aspirates (TA) and plasma (PL) was monitored by qPCR. CMV-specific T-cell immunity was assessed by intracellular cytokine staining. Plasma TNF-alpha levels were determined by ELISA. CMV reactivation occurred in 39.7% of patients (23% had CMV DNA detected only in TA). The analysis of TA allowed an earlier diagnosis in 28% of patients. Cle…
Optimized recombinant dense bodies of human cytomegalovirus efficiently prime virus specific lymphocytes and neutralizing antibodies without the addi…
2010
Control of human cytomegalovirus (HCMV) infection correlates with the reconstitution of antiviral T lymphocytes in haematopoietic stem cell transplant recipients. A vaccine to foster this reconstitution and to ameliorate the severe consequences of HCMV reactivation is yet unavailable. This work focused on providing a rationale for the amendment of the yields and the antigenic composition of a vaccine, based on subviral dense bodies (DB) of HCMV. Modified DB were generated that contained the HLA-A2 presented IE1 model peptide TMYGGISLL, integrated at different positions in the major DB protein pp65. Insertion at position W175 of pp65 allowed efficient formation of recDB in the cytoplasm of i…
Human cytomegalovirus pp71 stimulates major histocompatibility complex class i presentation of IE1-derived peptides at immediate early times of infec…
2013
ABSTRACT Suppression of major histocompatibility complex (MHC) class I-mediated presentation of human cytomegalovirus (HCMV) peptides is an important mechanism to avoid CD8 T lymphocyte recognition and killing of infected cells. Of particular interest is how MHC class I presentation of essential regulatory immediate early (IE) proteins of HCMV can be effectively compromised at times when known viral immunoevasins are not abundantly expressed. The tegument protein pp71 had been suggested to be involved in MHC class I downregulation. Intriguingly, this polypeptide is also critically engaged in the initial derepression of the major IE gene locus, leading to enhanced expression of IE proteins I…
γδT cells elicited by CMV reactivation after allo-SCT cross-recognize CMV and leukemia.
2013
Human cytomegalovirus (CMV) infections and relapse of disease remain major problems after allogeneic stem cell transplantation (allo-SCT), in particular in combination with CMV-negative donors or cordblood transplantations. Recent data suggest a paradoxical association between CMV reactivation after allo-SCT and reduced leukemic relapse. Given the potential of Vδ2-negative γδT cells to recognize CMV-infected cells and tumor cells, the molecular biology of distinct γδT-cell subsets expanding during CMV reactivation after allo-SCT was investigated. Vδ2(neg) γδT-cell expansions after CMV reactivation were observed not only with conventional but also cordblood donors. Expanded γδT cells were ca…
Cytomegalovirus and varicella–zoster virus vaccines in hematopoietic stem cell transplantation
2009
Impairment of cellular immunity upon hematopoietic stem cell transplantation (HSCT) may lead to serious clinical manifestations induced by human cytomegalovirus (HCMV) and varicella-zoster virus (VZV) infections. Although the clinical presentations, preferential organ involvement and clinical courses are different, infections with both herpesviruses are similar with respect to many pathophysiological aspects and the therapeutic strategies that are employed to combat them. Antiviral drug prophylaxis and therapy are successfully used to limit the risk of reactivated HCMV and VZV infections, but are unable to absolutely prevent episodes of virus disease in long-term follow-up after HSCT. Contr…
Application of a 5-bromo-2′-deoxyuridine ELISA for measuring the lymphoproliferative response to human cytomegalovirus in HIV-1-infected patients
2002
Assessment of the lymphoproliferative response to human cytomegalovirus (HCMV) may help to identify human immunodeficiency virus (HIV)-1-infected patients at high risk of developing HCMV end-organ disease. The tritiated thymidine ([3H]-TdR)-incorporation assay is the gold standard for measuring lymphoproliferative responses, though it is unsuitable as a routine laboratory procedure. An alternative non-radioactive technique, a 5-bromo-2'-deoxyuridine (BrdU) enzyme-linked immunosorbent assay, was applied for measuring T-cell proliferation in response to HCMV. Stimulation of either 1 x 10(5) or 5 x 10(4) peripheral blood mononuclear cells (PBMCs)/well with 10 PFU/well (before inactivation) of …
An evaluation of the role of NKG2C+natural killer cells in protection from cytomegalovirus DNAemia early following allogeneic stem cell transplantati…
2013
The role of natural killer (NK) cells in affording protection against human cytomegalovirus (CMV) in allogeneic stem cell transplant recipients is largely unknown. The current study was aimed at determining whether NKG2C+ NK cells confer protection from CMV DNAemia early following transplantation in patients lacking mono and polyfunctional CMV pp65 and IE-1-specific CD4+ and CD8+ T-cell responses, as measured by flow cytometry for intracellular cytokine staining. Fourteen out of the 36 patients included in this study developed CMV DNAemia between days +30 and +60 after transplant. Three patients did so after day +60. Peripheral blood levels of CD56(bright) CD16(-/low) and CD56(dim) CD16+ NK…