Search results for "Cytomegalovirus infections"

Failure of Cytomegalovirus-Specific CD8+ T Cell Levels at Viral DNAemia Onset to Predict the Eventual Need for Preemptive Antiviral Therapy in Alloge…

2018

Kinetics of cytomegalovirus (CMV) pp65 and IE-1-specific IFNgamma CD8+ and CD4+ T cells during episodes of viral DNAemia in allogeneic stem cell tran…

2010

The dynamics of CMV pp65 and IE-1-specific IFNgamma-producing CD8(+) (IFNgamma CD8(+)) and CD4(+) (IFNgamma CD4(+)) T cells and CMV DNAemia were assessed in 19 pre-emptively treated episodes of active CMV infection. Peripheral counts of IFNgamma CD8(+) and IFNgamma CD4(+) T cells inversely correlated with CMV DNAemia levels (P = <0.001 and P = 0.003, respectively). A threshold value of 1.3 cells/microl predicting CMV DNAemia clearance was established for IFNgamma CD8(+) T cells (PPV, 100%; NPV, 93%) and for IFNgamma CD4(+) T cells (PPV, 100%; NPV, 75%). Undetectable T-cell responses were usually observed at the time of initiation of pre-emptive therapy. Either a rapid (within 7 days) or a d…

Immunological insights into the pathogenesis of active CMV infection in non-immunosuppressed critically ill patients.

2011

Dissociation of cytomegalovirus (CMV) DNA loads between the lower respiratory tract and blood, with high levels in the former compartment and low or undetectable levels in the latter, commonly occurs during active CMV infection in critically ill patients despite the presence of high frequencies of CMV-specific IFN-γ-producing CD8+ and CD4+ T cells in blood. Data presented in this case report suggest that inter-compartmental differences in interleukin-10 (IL-10) levels may, in part, explain the pathobiology of this phenomenon. In the absence of ganciclovir treatment, a significant correlation was observed between IL-10 levels and CMV DNA loads in lower respiratory tract specimens (P = 0.016)…

Liposomally-entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients

1992

Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2-20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vit…

Enhancerless Cytomegalovirus Is Capable of Establishing a Low-Level Maintenance Infection in Severely Immunodeficient Host Tissues but Fails in Expon…

2010

ABSTRACT Major immediate-early transcriptional enhancers are genetic control elements that act, through docking with host transcription factors, as a decisive regulatory unit for efficient initiation of the productive virus cycle. Animal models are required for studying the function of enhancers paradigmatically in host organs. Here, we have sought to quantitatively assess the establishment, maintenance, and level of in vivo growth of enhancerless mutants of murine cytomegalovirus in comparison with those of an enhancer-bearing counterpart in models of the immunocompromised or immunologically immature host. Evidence is presented showing that enhancerless viruses are capable of forming restr…

Patchwork Pattern of Transcriptional Reactivation in the Lungs Indicates Sequential Checkpoints in the Transition from Murine Cytomegalovirus Latency…

1999

The lungs are a relevant organ site of primary and recurrent human cytomegalovirus (hCMV) disease (for overviews, see references 21, 22, 31, 34, 39, and 44). Murine CMV (mCMV) can serve us as a model for studying CMV pneumonia in acute infection (6, 27, 33, 37) as well as for studying viral latency, reactivation, and recurrence in the lungs (2, 17, 18, 42, 43). We have shown recently that transcription from the major immediate-early (MIE) transcription unit ie1-ie3 (hereafter referred to as ie1/3), which is driven by a strong MIE promoter-enhancer (MIEPE) (3), occurs during pulmonary latency of mCMV but fails to initiate the productive cycle (17). Notably, the paralogous MIEPE of hCMV can f…

Preemptive CD8 T-Cell Immunotherapy of Acute Cytomegalovirus Infection Prevents Lethal Disease, Limits the Burden of Latent Viral Genomes, and Reduce…

1998

ABSTRACT In the immunocompetent host, primary cytomegalovirus (CMV) infection is resolved by the immune response without causing overt disease. The viral genome, however, is not cleared but is maintained in a latent state that entails a risk of virus recurrence and consequent organ disease. By using murine CMV as a model, we have shown previously that multiple organs harbor latent CMV and that reactivation occurs with an incidence that is determined by the viral DNA load in the respective organ (M. J. Reddehase, M. Balthesen, M. Rapp, S. Jonjic, I. Pavic, and U. H. Koszinowski. J. Exp. Med. 179:185–193, 1994). This predicts that a therapeutic intervention capable of limiting the load of lat…

Differential diagnosis of cytomegalovirus infection and acute rejection by serum CC-Chemokine measurement after orthotopic liver transplantation

2003

Cytomegalovirus inhibits the engraftment of donor bone marrow cells by downregulation of hemopoietin gene expression in recipient stroma

1998

ABSTRACT Cytomegalovirus (CMV) disease after bone marrow (BM) transplantation is often associated with BM graft failure. There are two possible reasons for such a correlation. First, a poor hematopoietic reconstitution of unrelated etiology could promote the progression of CMV infection by the lack of immune control. Alternatively, CMV infection could interfere with the engraftment of donor BM cells in recipient BM stroma. Evidence for a causative role of CMV in BM aplasia came from studies in long-term BM cultures and from the murine in vivo model of CMV-induced aplastic anemia. A deficiency in the expression of essential stromal hemopoietins, such as stem cell factor (SCF), has indicated …

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…