Current management of CMV infection in cancer patients (solid tumors). Epidemiology and therapeutic strategies.

Little evidence is available regarding the incidence of CMV disease in patients with solid cancers. Latest data show that approximately 50 % of these patients with CMV PCR positivity developed clinically relevant CMV-viremia, and would require specific therapy. In the clinical arena, CMV reactivation is an important differential diagnosis in the infectological work up of these patients, but guidelines of management on this subject are not yet available. CMV reactivation should be considered during differential diagnosis for patients with a severe decline in lymphocyte counts when receiving chemoradiotherapy or immunochemotherapy with lymphocyte-depleting or blocking agents. Monitoring of CMV reactivation followed by the implementation of preemptive strategies or the establishment of early antiviral treatment improves the prognosis and reduces the morbidity and mortality of these patients.

Chemically sulfated polysaccharides from natural sources: Assessment of extraction-sulfation efficiencies, structural features and antiviral activities.

The provisioning of compound libraries with a high degree of diversity and attractive pharmacological properties is a limiting step in drug development. This study reports the production of highly bioactive sulfated polysaccharides, originally present in a nonsulfated, dormant state in natural sources, and demonstrates their antiviral activity (human cytomegalovirus EC50 values of 2.34-7.77 µg/mL) at a low degree of cytotoxicity. Furthermore, data strongly suggested the inhibition of virus entry as the main mode of antiviral action. Remarkably, the utilized oleum-DMF reagent was able to generate a range of sulfated polysaccharides from various natural sources, possessing varying saccharide compositions, degrees of sulfation (0.4-1.7) and molecular masses (38-94,000 g/mol). Typically, in a matter of minutes, this reagent not only solubilized polysaccharides but also chemically converted their hydroxyl functionality into sulfates. The most active sulfated polysaccharide (EC50 of 2.62 µg/mL) proved to be a 94,000 g/mol branched glucan with sulfates at C-6/C-3,6/C-2,3,6 positions. In conclusion, the important determinants of such compounds' antiviral activity are: (i) degree of sulfation, (ii) molecular mass and (iii) structural features. Thus, our approach offers a huge prospect for the improvement of natural source-derived libraries based on biologically active polysaccharides with diversified chemical profiles.

Burden of cytomegalovirus reactivation post kidney transplant with antithymocyte globulin use in Thailand: A retrospective cohort study.

Background: Cytomegalovirus (CMV) is an important cause of infectious complications after kidney transplantation (KT), especially among patients receiving antithymocyte globulin (ATG). CMV infection can result in organ dysfunction and indirect effects such as graft rejection, graft failure, and opportunistic infections . Prevention of CMV reactivation includes pre-emptive or prophylactic approaches. Access to valganciclovir prophylaxis is limited by high cost. Our objective is to determine the burden and cost of treatment for CMV reactivation/disease among KT recipients who received ATG in Thailand since its first use in our center. Methods: We conducted a single-center retrospective cohort study of KT patients who received ATG during 2010-2013. We reviewed patients' characteristics, type of CMV prophylaxis, incidence of CMV reactivation, and outcome (co-infections, graft function and death). We compared the treatment cost between patients with and without CMV reactivation. Results: Thirty patients included in the study had CMV serostatus D+/R+. Twenty-nine patients received intravenous ganciclovir early after KT as inpatients. Only three received outpatient valganciclovir prophylaxis. Incidence of CMV reactivation was 43%, with a median onset of 91 (range 23-1007) days after KT. Three patients had CMV end-organ disease; enterocolitis or retinitis. Infectious complication rate among ATG-treated KT patients was up to 83%, with a trend toward a higher rate among those with CMV reactivation ( P = 0.087). Patients with CMV reactivation/disease required longer duration of hospitalization ( P = 0.018). The rate of graft loss was 17%. The survival rate was 97%. The cost of treatment among patients with CMV reactivation was significantly higher for both inpatient setting ( P = 0.021) and total cost ( P = 0.035) than in those without CMV reactivation. Conclusions: Burden of infectious complications among ATG-treated KT patients was high. CMV reactivation is common and associated with longer duration of hospitalization and higher cost.

Pre-transplant assessment of CMV-specific immune response by Elispot assay in kidney transplant recipients.

Cytomegalovirus (CMV) primary infection or re-activation in solid organ transplant (SOT) recipients is associated with increased morbidity and mortality, with patients with IgG-CMV D+/R- sero-matching at greater risk. The impact of pre-transplant CMV-specific host cellular immunity on the long-term risk of CMV replication in kidney transplants (KT) was prospectively evaluated in eighty patients by CMV-EliSpot assay. The study population included 54 male and 26 female recipients, with CMV-IgG distribution: 60 D+/R+, 11 D-/R+, 7 D+/R-, 2 D-/R-. At pre-transplantation, 49 KT (61.3%) were CMV-responders by EliSpot. At 3-month follow up, 16 (32.7%) out of 49 CMV-responders showed CMV blood infection, compared to 8 (25.8%) out of 31 non-responders. No further episode of CMV viraemia was reported in the responder group, in comparison to 15 out 31 non-responders (48.4%) showing at least one episode of CMV-DNAemia at 12-month follow-up. Baseline CMV-IgG serology showed a strong correlation with EliSpot determinations; KT recipients exhibiting at least one episode of CMV viraemia at 12-month follow-up showed lower baseline CMV-EliSpot values than those without signs of CMV replication. The study suggests that monitoring CMV-specific T-cell responses at pre-transplantation by EliSpot assay may be useful for predicting the post-transplantation risk of CMV infection and reactivation.

Clinical assessment of anti-viral CD8+ T cell immune monitoring using QuantiFERON-CMV® assay to identify high risk allogeneic hematopoietic stem cell transplant patients with CMV infection complications.

The reconstitution of anti-viral cellular immunity following hematopoietic stem cell transplantation (HSCT) is crucial in preventing cytomegalovirus (CMV)-associated complications. Thus immunological monitoring has emerged as an important tool to better target pre-emptive anti-viral therapies. However, traditional laboratory-based assays are too cumbersome and complicated to implement in a clinical setting. Here we conducted a prospective study of a new whole blood assay (referred to as QuantiFERON-CMV®) to determine the clinical utility of measuring CMV-specific CD8+ T-cell responses as a prognostic tool. Forty-one evaluable allogeneic HSCT recipients underwent weekly immunological monitoring from day 21 post-transplant and of these 21 (51.2%) showed CMV reactivation and 29 (70.7%) developed acute graft-versus-host disease (GvHD). Patients with acute GvHD (grade ≥ 2) within 6 weeks of transplant showed delayed reconstitution of CMV-specific T-cell immunity (p = 0.013) and a higher risk of CMV viremia (p = 0.026). The median time to stable CMV-specific immune reconstitution was 59 days and the incidence of CMV reactivation was lower in patients who developed this than those who did not (27% versus 65%; p = 0.031). Furthermore, a failure to reconstitute CMV-specific immunity soon after the onset of CMV viraemia was associated with higher peak viral loads (5685 copies/ml versus 875 copies/ml; p = 0.002). Hence, QuantiFERON-CMV® testing in the week following CMV viremia can be useful in identifying HSCT recipients at risk of complicated reactivation.

Assessment of natural killer cell responses to human cytomegalovirus-infected macrophages.

Natural killer (NK) cells are major components of the innate immune system and are assumed to play an important role in the defense against cytomegalovirus infection. Human cytomegalovirus (HCMV) is the only virus known that shapes the NK cell receptor repertoire in humans. Assays allowing the simultaneous measurement of multiple cell parameters and the assessment of subpopulations of NK cells are suitable for monitoring the NK cell response to infected cells. Herein, we describe an autologous assay system to assess NK cell responses to HCMV-infected macrophages which is based on flow cytometry to detect CD107a expression and interferon gamma (IFNγ) secretion. Further we established a simple method to handle HCMV-infected macrophages. Our assay provides a practicable approach to investigate NK cell responses to HCMV infection in vitro.

Longitudinal assessment of cytomegalovirus (CMV)-specific immune responses in liver transplant recipients at high risk for late CMV disease.

Cytomegalovirus (CMV)-seronegative recipients (R(-)) of a liver transplant from CMV-positive donors (D(+)) are at high risk for developing late CMV disease after discontinuation of antiviral prophylaxis. Levels of viremia and CMV-specific interferon (IFN)- gamma -producing CD4(+) and IFN- gamma -producing CD8(+) T cell responses were prospectively measured from discontinuation of antiviral prophylaxis until 1 year after transplantation in 17 consecutive D(+)/R(-) patients. CMV loads of >1000 copies/mL were strongly associated with CMV disease in the 6 symptomatic patients. Despite immunosuppression, broadly diverse T cells specific for CMV lysate or peptide libraries spanning pp65 and immediate early (IE) 1 immunodominant CMV antigens developed in all patients. A vigorous CD8(+) T cell response to pp65 and IE1 antigens characterized the D(+)/R(-) cohort. Unexpectedly, none of these responses were predictive of CMV disease or viremia. No significant lymphopenia or functional impairment of CMV-specific T cells was detected in the symptomatic patients, whose morbidity was resolved after antiviral treatment while measurable CMV immunity was maintained during the 1-year observation period.

Cytomegalovirus DNAemia and disease: incidence, natural history and management in settings other than allogeneic stem cell transplantation.

BACKGROUND AND OBJECTIVES: Despite increasing intensity and profound immunosuppression associated with newer therapies for hematologic malignancies, little information exists regarding cytomegalovirus (CMV) reactivation in settings other than allogeneic stem cell transplantation (SCT). DESIGN AND METHODS: We reviewed the epidemiology of CMV disease in patients who were CMV polymerase chain reaction (PCR) positive during treatment for hematologic malignancies without allogeneic SCT from June 1999 to June 2004. RESULTS: Thirty-six patients with CMV reactivation were identified. Of these, 92% were undergoing investigation for fever. Fifteen patients with CMV DNAemia were treated with ganciclovir without CMV disease developing. Notably, 20 patients with untreated CMV DNAemia did not develop CMV disease during a median follow-up of 3.5 (1-19) months. The highest rates of reactivation were observed with HyperCVAD (7.8%) and alemtuzumab (50%). INTERPRETATION AND CONCLUSIONS: We recommend that screening for CMV DNAemia be instituted and pre-emptive therapy contemplated for asymptomatic CMV reactivation only in patients receiving alemtuzumab therapy, but not routinely for other patients outside the allogeneic SCT setting. Indeed for such patients, detection of isolated CMV DNAemia does not imply the need for immediate therapy and future studies are needed to validate PCR detection of CMV DNA and CMV DNA titers as predictors for CMV disease.

A prospective assessment of valganciclovir for the treatment of cytomegalovirus infection and disease in transplant recipients.

We assessed valganciclovir for the treatment of cytomegalovirus (CMV) in organ-transplant recipients. Virologic and clinical outcomes were compared with those in matched historical control individuals. Thirty-two patients (23 with symptomatic disease) received valganciclovir, and 32 patients received intravenous (iv) ganciclovir. The rate of virologic clearance by day 21 of therapy was similar in the valganciclovir arm (50.0%) and the ganciclovir arm (46.9%) (P value not significant). The change from baseline viral load by day 7 and day 14 of therapy was similar in both arms. Two patients treated with valganciclovir required a switch to iv ganciclovir, because of a lack of response. Valganciclovir is useful for the treatment of CMV infection and disease in selected organ-transplant recipients.

Assessment of CMV load in solid organ transplant recipients by pp65 antigenemia and real-time quantitative DNA PCR assay: correlation with pp67 RNA detection.

After bone marrow (BM) or solid-organ (SO) transplantation viremic Cytomegalovirus (CMV) infection is observed frequently. Quantitative assay of CMV in blood helps the management of this clinical condition. In the present report, 83 samples from 39 solid organ recipients, three CMV assays were compared simultaneously for the first time: the Nuclisens CMV pp67 assay (nucleic acid sequence-based amplification, NASBA), an "in-house" quantitative real-time PCR assay (TaqMan) for CMV DNA, and pp65 antigenemia. The relation between CMV DNA and pp65 antigenemia, the quantitative assays, was evaluated on a larger group including 251 blood samples from 118 solid organ recipients. Real-time PCR provided the best results; > or =130 CMV DNA copies/2 x 10(5) peripheral blood leukocytes (PBLs) predicted > or =1 pp65 antigen positive (Ag+) cell/2 x 10(5) PBLs. By taking pp65 antigenemia as the "gold standard," the sensitivity of CMV DNA quantitation and of the pp67 RNA assay were 0.95 and 0.20, respectively, while the corresponding specificity values were 0.50 and 0.93. When real-time PCR was considered as the "gold standard," the sensitivity and specificity of the pp65 antigenemia were 0.65 and 0.91, respectively. Among the three tests examined, the sensitivity of the pp67 RNA assay was the lowest. On the other hand, the pp67 RNA assay was highly specific and effective in pinpointing high viremia patients. The present report, by providing predictive values for all three diagnostic profiles, DNA load, antigenemia, and pp67RNA, is a contribution for validation of real-time PCR as a new standard for quantitative assessment of CMV viremia in clinical settings.

Cytomegalovirus infection in the liver transplant recipient. Epidemiology, pathogenesis, and clinical management.

The effects of cytomegalovirus (CMV) on the liver transplant patient can be divided into two general categories: the direct infectious disease effects (e.g. CMV mononucleosis, hepatitis, pneumonitis, GI infection) and the indirect effects that are mediated by cytokines elaborated as a consequence of the infection. These indirect effects include an immunosuppressive effect that contributes to the development of superinfection with fungi, bacteria, and Pneumocystis carinii; a role in the pathogenesis of allograft injury; and a role in the development of post-transplant lymphoproliferative disease. The two key steps in the pathogenesis of CMV infection-reactivation of the virus from latency and systemic spread-are modulated by the immunosuppressive therapy administered. New antiviral programs, primarily those involving ganciclovir, have resulted in considerable progress in the prevention and treatment of CMV disease among liver transplant recipients.