Active Virus Infection Research Articles

Murine Cytomegalovirus Infection of Melanoma Lesions Delays Tumor Growth by Recruiting and Repolarizing Monocytic Phagocytes in the Tumor.

Cytomegalovirus (CMV) is a ubiquitous betaherpesvirus that infects many different cell types. Human CMV (HCMV) has been found in several solid tumors, and it has been hypothesized that it may promote cellular transformation or exacerbate tumor growth. Paradoxically, in some experimental situations, murine CMV (MCMV) infection delays tumor growth. We previously showed that wild-type MCMV delayed the growth of poorly immunogenic B16 melanomas via an undefined mechanism. Here, we show that MCMV delayed the growth of these immunologically "cold" tumors by recruiting and modulating tumor-associated macrophages. Depletion of monocytic phagocytes with clodronate completely prevented MCMV from delaying tumor growth. Mechanistically, our data suggest that MCMV recruits new macrophages to the tumor via the virus-encoded chemokine MCK2, and viruses lacking this chemokine were unable to delay tumor growth. Moreover, MCMV infection of macrophages drove them toward a proinflammatory (M1)-like state. Importantly, adaptive immune responses were also necessary for MCMV to delay tumor growth as the effect was substantially blunted in Rag-deficient animals. However, viral spread was not needed and a spread-defective MCMV strain was equally effective. In most mice, the antitumor effect of MCMV was transient. Although the recruited macrophages persisted, tumor regrowth correlated with a loss of viral activity in the tumor. However, an additional round of MCMV infection further delayed tumor growth, suggesting that tumor growth delay was dependent on active viral infection. Together, our results suggest that MCMV infection delayed the growth of an immunologically cold tumor by recruiting and modulating macrophages in order to promote anti-tumor immune responses.IMPORTANCE Cytomegalovirus (CMV) is an exciting new platform for vaccines and cancer therapy. Although CMV may delay tumor growth in some settings, there is also evidence that CMV may promote cancer development and progression. Thus, defining the impact of CMV on tumors is critical. Using a mouse model of melanoma, we previously found that murine CMV (MCMV) delayed tumor growth and activated tumor-specific immunity although the mechanism was unclear. We now show that MCMV delayed tumor growth through a mechanism that required monocytic phagocytes and a viral chemokine that recruited macrophages to the tumor. Furthermore, MCMV infection altered the functional state of macrophages. Although the effects of MCMV on tumor growth were transient, we found that repeated MCMV injections sustained the antitumor effect, suggesting that active viral infection was needed. Thus, MCMV altered tumor growth by actively recruiting macrophages to the tumor, where they were modulated to promote antitumor immunity.

Virome capture sequencing does not identify active viral infection in unicentric and idiopathic multicentric Castleman disease.

Castleman disease (CD) describes a spectrum of heterogeneous disorders defined by characteristic lymph node histopathology. Enlarged lymph nodes demonstrating CD histopathology can occur in isolation (unicentric CD; UCD) sometimes accompanied by mild symptoms, or at multiple sites (multicentric CD, MCD) with systemic inflammation and cytokine-driven multi-organ dysfunction. The discovery that Kaposi sarcoma herpesvirus/human herpesvirus (HHV)-8 drives MCD in a subset of patients has led to the hypotheses that UCD and MCD patients with negative HHV-8 testing by conventional methods may represent false negatives, or that these cases are driven by another virus, known or unknown. To investigate these hypotheses, the virome capture sequencing for vertebrate viruses (VirCapSeq-VERT) platform was employed to detect RNA transcripts from known and novel viruses in fresh frozen lymph node tissue from CD patients (12 UCD, 11 HHV-8-negative MCD [idiopathic MCD; iMCD], and two HHV-8-positive MCD) and related diseases (three T cell lymphoma and three Hodgkin lymphoma). This assay detected HHV-8 in both HHV-8-positive cases; however, HHV-8 was not found in clinically HHV-8-negative iMCD or UCD cases. Additionally, no novel viruses were discovered, and no single known virus was detected with apparent association to HHV-8-negative CD cases. Herpesviridae family members, notably including Epstein-Barr virus (EBV), were detected in 7 out of 12 UCD and 5 of 11 iMCD cases with apparent correlations with markers of disease severity in iMCD. Analysis of a separate cohort of archival formalin-fixed, paraffin-embedded lymph node tissue by In situ hybridization revealed significantly fewer EBV-positive cells in UCD and iMCD compared to tissue from HHV-8-positive MCD and EBV-associated lymphoproliferative disorder. In an additional cohort, quantitative testing for EBV by PCR in peripheral blood during disease flare did not detect systemic EBV viremia, suggesting detection lymph node tissue is due to occult, local reactivation in UCD and iMCD. This study confirms that HHV-8 is not present in UCD and iMCD patients. Further, it fails to establish a clear association between any single virus, novel or known, and CD in HHV-8-negative cases. Given that distinct forms of CD exist with viral and non-viral etiological drivers, CD should be considered a group of distinct and separate diseases with heterogeneous causes worthy of further study.

Expression of the p24 silencing suppressor of Grapevine leafroll-associated virus 2 from Potato virus X or Barley stripe mosaic virus vector elicits hypersensitive responses in Nicotiana benthamiana

The 24-kDa protein (p24) encoded by Grapevine leafroll-associated virus 2 (GLRaV-2) is an RNA-silencing suppressor (RSS), but its effect on active viral infection is unclear. Using a Potato virus X (PVX)-based expression system, we demonstrated that p24 elicits lethal systemic necrosis in Nicotiana benthamiana, sharing typical characteristics of the hypersensitive response (HR), and that NbRAR1 (a cytoplasmic Zn2+-binding protein) is involved in the PVX–p24-mediated systemic necrosis. Moreover, expression of p24 from Barley stripe mosaic virus (BSMV) vector triggered local necrosis in infiltrated patches of N. benthamiana, likely inhibiting viral systemic spread. By deletion analysis, we demonstrated that amino acids (aa) 1 to 180, which are located in the region (aa 1–188) previously shown to be necessary for p24's RSS activity, is sufficient for p24 to elicit systemic necrosis in the context of PVX infection. Using substitution mutants, we revealed that silencing-suppression-defective mutants R2A and W54A induce only a mild necrotic response; two mutants without self-interaction ability previously shown to lose or retain weak suppression function also displayed decreased pathogenicity: W149A without RSS activity elicited a mild necrotic response, whereas V162H/L169H/L170H which retains weak RSS activity was able to induce systemic necrosis, but with a 1- to 2-day delay. Taken together, p24 plays an important role in GLRaV-2 pathogenesis, triggering HR-like necrosis in N. benthamiana plants when expressed from PVX or BSMV vector; both the silencing suppression and self-interaction are crucial for p24's pathogenicity activity, and the region of p24 for determining systemic necrosis is mapped to aa 1–180.

Lymphoplasmacytic Meningoencephalitis and Neuronal Necrosis Associated With Parvoviral Infection in Cats.

Neurologic manifestations other than cerebellar hypoplasia are rarely associated with feline panleukopenia virus (FPV) infection in cats. Here the authors describe lymphoplasmacytic meningoencephalitis and neuronal necrosis in 2 cats autopsied after exhibiting ataxia and nystagmus. Gross changes consisted of cerebellar herniation through the foramen magnum, with flattening of cerebrocortical gyri and narrowing of sulci. Histologically, lymphoplasmacytic meningoencephalitis, extensive neuronal necrosis, and neuroaxonal degeneration with digestion chambers were present in the telencephalon and brain stem in both cats. Frozen brain tissue of both cats was positive for parvoviral antigen via fluorescent antibody testing, and formalin-fixed, paraffin-embedded tissue sections of brain were immunoreactive for parvovirus antigen and positive for parvoviral DNA on in situ hybridization. Frozen brain tissue from 1 case was positive for parvovirus NS1 and VP2 genes using conventional polymerase chain reaction, and subsequent DNA sequencing and phylogenetic analysis revealed that the viral strain was a FPV. Reverse transcription quantitative polymerase chain reaction on formalin-fixed, paraffin-embedded brain tissue revealed high levels of parvovirus in both cases, supporting an acute and active viral infection. Although rare, FPV infection should be considered in cases of lymphoplasmacytic meningoencephalitis and neuronal necrosis in cats.

Hepatocellular Carcinoma Risk Stratification by Genetic Profiling in Patients with Cirrhosis.

Prediction of future hepatocellular carcinoma (HCC) risk in the sizable chronic liver disease population is an urgent unmet need to enable regular HCC screening for early detection. Germline deoxyribonucleic acid polymorphisms likely represent etiology-specific host factors that determine HCC susceptibility, including single nucleotide polymorphisms in EGF, IFNL3, MICA, and TLL1 in hepatitis C with or without active viral infection, and PNPLA3, TM6SF2, and MBOAT7 in metabolic liver diseases. Transcriptome-based prognostic liver signature in diseased liver tissue has been associated with long-term HCC risk in viral and metabolic etiologies. Transcriptomic signatures of hepatic injury and specific cell type such as aggregated lymphocytes also predict HCC development. Circulating factors such as proteins and their chemical modification, nucleotides, and metabolites may serve for less-invasive assessment of short- or long-term HCC risk. These biomarkers will enable individual HCC risk-based personalized clinical management for cost-effective early HCC detection and improvement of patient survival.

Active and diverse viruses persist in the deep sub-seafloor sediments over thousands of years

Viruses are ubiquitous and cause significant mortality in marine bacterial and archaeal communities. Little is known about the role of viruses in the sub-seafloor biosphere, which hosts a large fraction of all microbes on Earth. We quantified and characterized viruses in sediments from the Baltic Sea. The results show that the Baltic Sea sub-seafloor biosphere harbors highly abundant viruses with densities up to 1.8 × 1010 viruses cm−3. High potential viral production down to 37 meters below seafloor in ca. 6000-years-old sediments and infected prokaryotic cells visible by transmission electron microscopy demonstrate active viral infection. Morphological and molecular data indicate that the highly diverse community of viruses includes both allochthonous input from the overlying seawater and autochthonous production. The detection of cyanophage-like sequences showed that viruses of phototrophic hosts may persist in marine sediments for thousands of years. Our results imply that viruses influence sub-seafloor microbial community dynamics and thereby affect biogeochemical processes in the sub-seafloor biosphere.

Dynamic marine viral infections and major contribution to photosynthetic processes shown by spatiotemporal picoplankton metatranscriptomes

Viruses provide top-down control on microbial communities, yet their direct study in natural environments was hindered by culture limitations. The advance of bioinformatics enables cultivation-independent study of viruses. Many studies assemble new viral genomes and study viral diversity using marker genes from free viruses. Here we use cellular metatranscriptomics to study active community-wide viral infections. Recruitment to viral contigs allows tracking infection dynamics over time and space. Our assemblies represent viral populations, but appear biased towards low diversity viral taxa. Tracking relatives of published T4-like cyanophages and pelagiphages reveals high genomic continuity. We determine potential hosts by matching dynamics of infection with abundance of particular microbial taxa. Finally, we quantify the relative contribution of cyanobacteria and viruses to photosystem-II psbA (reaction center) expression in our study sites. We show sometimes >50% of all cyanobacterial+viral psbA expression is of viral origin, highlighting the contribution of viruses to photosynthesis and oxygen production.

Substantial improvement in immune thrombocytopenic purpura associated with T-cell/histiocyte-rich B-cell lymphoma treated with chemotherapy: A case report.

Immune thrombocytopenic purpura (ITP) is characterized by antibody and immune platelet destruction, occasionally leading to life-threatening hemorrhage. ITP is a frequent complication of chronic lymphoid leukemia, but is rarely associated with diffuse large B-cell lymphoma (DLBCL). We herein describe a case of ITP associated with T-cell/histiocyte-rich B-cell lymphoma (T/HRBCL), which is a rare variant of DLBCL. A 54-year-old man presented with fever, multiple lymphadenopathies, petechial purpura and intraoral mucosal hemorrhage. Laboratory data revealed thrombocytopenia, normal white blood cell count, mild anemia, no active viral infections, and no autoimmune antibodies. Multiple lymphadenopathies were observed on computed tomography. A bone marrow biopsy revealed minor hypercellularity with increased number of megakaryocytes; however, there were no pathological cells or phagocytic cells. The patient was diagnosed with ITP; concurrently, he was also diagnosed with T/HRBCL via lymph node biopsy, and was treated accordingly with a chemotherapeutic regimen comprising rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone. Prompt reduction in the size of the superficial lymph nodes and an increase of the platelet count were observed simultaneously. To the best of our knowledge, this is the first report of T/HRBCL complicated by ITP. The findings strongly suggest a causative association between ITP and T/HRBCL.

Viral metagenomics revealed novel betatorquevirus species in pediatric inpatients with encephalitis/meningoencephalitis from Ghana

The cause of acute encephalitis/meningoencephalitis in pediatric patients remains often unexplained despite extensive investigations for large panel of pathogens. To explore a possible viral implication, we investigated the virome of cerebrospinal fluid specimens of 70 febrile pediatric inpatients with clinical compatible encephalitis/meningoencephalitis. Using viral metagenomics, we detected and genetically characterized three novel human Torque teno mini virus (TTMV) species (TTMV-G1-3). Phylogenetically, TTMV-G1-3 clustered in three novel monophyletic lineages within genus Betatorquevirus of the Anelloviridae family. TTMV-G1-3 were highly prevalent in diseased children, but absent in the healthy cohort which may indicate an association of TTMV species with febrile illness. With 2/3 detected malaria co-infection, it remains unclear if these novel anellovirus species are causative agents or increase disease severity by interaction with malaria parasites. The presence of the viruses 28 days after initiating antimalarial and/or antibiotic treatment suggests a still active viral infection likely as effect of parasitic and/or bacterial co-infection that may have initiated a modulated immune system environment for viral replication or a defective virus clearance. This study increases the current knowledge on the genetic diversity of TTMV and strengthens that human anelloviruses can be considered as biomarkers for strong perturbations of the immune system in certain pathological conditions.

Non-CMV Viral Infections Following Solid-Organ Transplantation – Focus on Human T-Cell Lymphotropic Virus Type-1 and Human Herpesviruses-6,-7 and -8

In non-endemic areas, HTLV-1 is an uncommon pathogen in the transplant host but can be associated with significant morbidity and mortality. Careful assessment of risk factors, targeted screening and heightened awareness of the clinical presentation of HTLV-1 associated disease is necessary for timely recognition and management in the transplant host. The use of antiretroviral agents in the management of symptomatic disease due to HTLV-1 remains controversial. HHV-6 has long been recognized as a pathogen in the transplant host however, establishing pathogenicity remains a challenge in clinical situations due to its ubiquitous nature, overlapping clinical manifestations and clustering of infection with other beta-herpesviruses. HHV-6 has the unique ability to undergo integration into the host chromosome and has been reported in ~1% of solid-organ and allogeneic stem cell transplant population. Increased recognition of this entity is needed as it can be mistaken for active viral infection and can lead to unnecessary use of antiviral medications. Current guidelines recommend against screening and treatment of asymptomatic HHV-6 infection in the solid-organ transplant host. HHV-7 is often diagnosed as co-infection with other beta-herpesviruses but pathogenicity is less clear. No clinical syndrome solely attributable to HHV-7 has been identified. HHV-8 infection following organ transplantation can be due to primary acquisition from donor or non-donor derived exposures; or secondary to reactivation of latent infection in a seropositive recipient. Kaposi sarcoma is the most common HHV-8 associated post-transplant complication however, there is increasing recognition of non-neoplastic syndromes of febrile illness with bone marrow suppression and hemophagocytic syndrome. Lack of standardized laboratory assays remains an impediment to targeted screening and diagnosis of HHV-8 associated complications. There is accumulating data on the role of mTOR inhibitors and HIV protease inhibitors particularly nelfinavir in the treatment of KS however, data in the transplant host is sparse. Multi-disciplinary approach is needed for management of HHV-8 associated complications.

RNA Sequencing of the In Vivo Human Herpesvirus 6B Transcriptome To Identify Targets for Clinical Assays Distinguishing between Latent and Active Infections

Human herpesvirus 6B (HHV-6B) DNA is frequently detected in human samples. Diagnostic assays distinguishing HHV-6B reactivation from latency are limited. This has impaired strategies to diagnose and treat HHV-6B-associated diseases. We used RNA sequencing to characterize and compare the HHV-6B transcriptome in multiple sample types, including (i) whole blood from hematopoietic cell transplant (HCT) recipients with and without HHV-6B plasma viremia, (ii) tumor tissue samples from subjects with large B cell lymphoma infected with HHV-6B, (iii) lymphoblastoid cell lines (LCLs) from subjects with inherited chromosomally integrated HHV-6B or latent infection with HHV-6B, and (iv) HHV-6B Z29 infected SupT1 CD4+ T cells. We demonstrated substantial overlap in the HHV-6B transcriptome observed in in vivo and in vitro samples, although there was variability in the breadth and quantity of gene expression across samples. The HHV-6B viral polymerase gene U38 was the only HHV-6B transcript detected in all next-generation RNA sequencing (RNA-seq) data sets and was one of the most highly expressed genes. We developed a novel reverse transcription-PCR assay targeting HHV-6B U38, which identified U38 mRNA in all tested whole-blood samples from patients with concurrent HHV-6B viremia. No HHV-6B U38 transcripts were detected by RNA-seq or reverse transcription-real-time quantitative PCR (RT-qPCR) in whole-blood samples from subjects without HHV-6B plasma detection or from latently infected LCLs. A RT-qPCR assay for HHV-6B U38 may be useful to identify lytic HHV-6B infection in nonplasma samples and samples from individuals with inherited chromosomally integrated HHV-6B. This study also demonstrates the feasibility of transcriptomic analyses for HCT recipients.IMPORTANCE Human herpesvirus 6B (HHV-6B) is a DNA virus that infects most children within the first few years of life. After primary infection, HHV-6B persists as a chronic, latent infection in many cell types. Additionally, HHV-6B can integrate into germ line chromosomes, resulting in individuals with viral DNA in every nucleated cell. Given that PCR to detect viral DNA is the mainstay for diagnosing HHV-6B infection, the characteristics of HHV-6B infection complicate efforts to distinguish between latent and active viral infection, particularly in immunocompromised patients who have frequent HHV-6B reactivation. In this study, we used RNA sequencing to characterize the HHV-6B gene expression profile in multiple sample types, and our findings identified evidence-based targets for diagnostic tests that distinguish between latent and active viral infection.

Footprints of BK and JC polyomaviruses in specimens from females affected by spontaneous abortion.

Are JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) infections associated with spontaneous abortion (SA)? There is no association of JCPyV or BKPyV with SA. A large number of risk factors have been associated with SA. The role of polyomaviruses, including JCPyV and BKPyV, in SA remains to be clarified. This is a case-control study including women affected by spontaneous abortion (SA, n = 100, the cases) and women who underwent voluntary interruption of pregnancy (VI, n = 100, the controls). Viral DNAs were investigated by qualitative PCR and quantitative droplet-digital PCR (ddPCR) in matched chorionic villi tissues and peripheral blood mononuclear cells (PBMCs) from SA (n = 100) and VI (n = 100). Indirect ELISAs with mimotopes/synthetic peptides corresponding to JCPyV and BKPyV viral capsid protein 1 epitopes were then employed to investigate specific IgG antibodies against JCPyV and BKPyV in human sera from SA (n = 80) and VI (n = 80) cohorts. JCPyV DNA was detected in 51% and 61% of SA and VI samples, respectively, with a mean viral DNA load of 7.92 copy/104 cells in SA and 5.91 copy/104 cells in VI (P > 0.05); BKPyV DNA was detected in 11% and 12% of SA and VI specimens, respectively, with a mean viral DNA load of 2.7 copy/104 cells in SA and 3.08 copy/104 cells in VI (P > 0.05). JCPyV was more prevalent than BKPyV in both SA and VI specimens (P < 0.0001). In PBMCs from the SA and VI cohorts, JCPyV DNA was detected with a prevalence of 8% and 12%, respectively, with a mean viral DNA load of 2.29 copy/104 cells in SA and 1.88 copy/104 cells in VI (P > 0.05). The overall prevalence of serum IgG antibodies against JCPyV detected by indirect ELISAs was 52.5% and 48.7% in SA and VI groups, respectively, whereas BKPyV-positive sera were found in 80% SA and 78.7% VI samples. This study did not investigate the presence of viral mRNA and/or proteins, which are indicative of an active viral infection, and these might be taken into consideration in future studies. JCPyV and BKPyV DNA sequences were detected and quantitatively analyzed for the first time by PCR/ddPCR in chorionic villi tissues and PBMCs from SA and VI specimens. Moreover specific immunological approaches detected serum IgG against JCPyV/BKPyV. Statistical analyses, however, do not indicate an association between these polyomaviruses and SA. This work was supported by the University of Ferrara, FAR research grants and the University Hospital of Ferrara/University of Ferrara joint grant. No potential conflicts of interest were disclosed.

De-Escalation of Antimicrobials in Adult Hematopoietic Cell Transplantation Recipients with Febrile Neutropenia of Unknown Origin

De-Escalation of Antimicrobials in Adult Hematopoietic Cell Transplantation Recipients with Febrile Neutropenia of Unknown Origin

Diversity of Active Viral Infections within the Sphagnum Microbiome.

Sphagnum-dominated peatlands play an important role in global carbon storage and represent significant sources of economic and ecological value. While recent efforts to describe microbial diversity and metabolic potential of the Sphagnum microbiome have demonstrated the importance of its microbial community, little is known about the viral constituents. We used metatranscriptomics to describe the diversity and activity of viruses infecting microbes within the Sphagnum peat bog. The vegetative portions of six Sphagnum plants were obtained from a peatland in northern Minnesota, and the total RNA was extracted and sequenced. Metatranscriptomes were assembled and contigs were screened for the presence of conserved virus marker genes. Using bacteriophage capsid protein gp23 as a marker for phage diversity, we identified 33 contigs representing undocumented phages that were active in the community at the time of sampling. Similarly, RNA-dependent RNA polymerase and the nucleocytoplasmic large DNA virus (NCLDV) major capsid protein were used as markers for single-stranded RNA (ssRNA) viruses and NCLDV, respectively. In total, 114 contigs were identified as originating from undescribed ssRNA viruses, 22 of which represent nearly complete genomes. An additional 64 contigs were identified as being from NCLDVs. Finally, 7 contigs were identified as putative virophage or polinton-like viruses. We developed co-occurrence networks with these markers in relation to the expression of potential-host housekeeping gene rpb1 to predict virus-host relationships, identifying 13 groups. Together, our approach offers new tools for the identification of virus diversity and interactions in understudied clades and suggests that viruses may play a considerable role in the ecology of the Sphagnum microbiome.IMPORTANCESphagnum-dominated peatlands play an important role in maintaining atmospheric carbon dioxide levels by modifying conditions in the surrounding soil to favor the growth of Sphagnum over that of other plant species. This lowers the rate of decomposition and facilitates the accumulation of fixed carbon in the form of partially decomposed biomass. The unique environment produced by Sphagnum enriches for the growth of a diverse microbial consortia that benefit from and support the moss's growth, while also maintaining the hostile soil conditions. While a growing body of research has begun to characterize the microbial groups that colonize Sphagnum, little is currently known about the ecological factors that constrain community structure and define ecosystem function. Top-down population control by viruses is almost completely undescribed. This study provides insight into the significant viral influence on the Sphagnum microbiome and identifies new potential model systems to study virus-host interactions in the peatland ecosystem.

Efficacy of Sofosbuvir-Based Anti-Viral Therapy in Preventing Post-Transplant Recurrence of HCV

Introduction: Hepatitis C virus (HCV) infection is a leading cause of end-stage liver disease in Pakistan and the most common indication for liver transplantation in the country. Recurrence of HCV infection following liver transplantation leads to accelerated fibrosis and progression to cirrhosis. Rates of graft loss and patient mortality also are markedly higher for patients with recurrent HCV than for uninfected patients. Retransplantation frequently is associated with a poor outcome. Sofosbuvir is a nucleotide polymerase inhibitor of NS5B-directed HCV-RNA replication. Administration of sofosbuvir with ribavirin is associated with rapid decreases of HCV RNA to undetectable levels in patients with HCV genotype 1, 2, 3, 4, and 6 infections.This study aimed at investigating the efficacy of Sofosbuvir based anti-viral therapy in post-transplant patients with recurrent HCV infection Methods: This was a retrospective analysis of medical records of patients who had received Sofosbuvir based combinations to treat active viral infection in the post-transplant setting Response to therapy was determined via SVR 12 and SVR 24. Patients aged 18 to 80 were included in this study. Patients with HCV/ HBV coinfection, CKD with eGFR < 30 ml/ min and HCV/ HIV co-infection were excluded. Data was collected using a structured questionnaire in 25 patients (21 males and 4 females). Frequencies and percentages were calculated to examine the responses Results: The results of the study showed that amongst patients who had started treatment within one year post transplant, SVR12 was achieved by in 95%, and SVR24 was achieved in 90%.of the patients. Moreover, the findings showed meaningful correlation of SVR12 and SVR24 with a93% concordance. Among those patients (2/25-8%) that were unable to achieve SVR12 or end of treatment response the main factor was lack of compliance or discontinuation of treatment. Conclusion: The sofosbuvir based anti-viral therapy in post-transplant patients is effective and safe in preventing HCV recurrence. Treatment of HCV in the post-transplant period can lead to better outcomes and should therefore be offered to all patients.

Clinical course of human herpesvirus 6 infection in pediatric living donor liver transplantation.

Differentiation between active and latent viral infection is critical for analysis of HHV-6-associated disease. HHV-6 infection has been associated with several clinical manifestations; however, the precise role of HHV-6 in pediatric LDLT remains unclear. This retrospective cohort study included 33 pediatric patients who received LDLT. All of the recipients were monitored for HHV-6 infection using viral isolation and real-time PCR. HHV-6 infection was observed in 14 of 33 (42.4%) recipients, and HHV-6B infection occurred within 2weeks after LDLT in 10 of 14 (71.4%) recipients. HHV-6 was isolated from 10 of 33 (30.3%) recipients. Multivariate analysis showed that independent predictors of HHV-6B infection were age (OR 0.975; 95% CI 0.943-0.999; P=.041), PELD (OR 1.091; P=.038), and biliary atresia (OR 16.48; P=.035). The occurrence of unexplained fever was significantly higher in recipients with HHV-6B infection (11/14) compared with uninfected recipients (6/19) (P=.013). Additionally, ALT levels at 8 and 9weeks after transplantation were significantly higher in the recipients with HHV-6B infection. Younger age, high MELD/PELD score, and biliary atresia as an underlying disease were identified as risk factors for viral infection.

A novel sampling method to detect airborne influenza and other respiratory viruses in mechanically ventilated patients: a feasibility study

BackgroundRespiratory viruses circulate constantly in the ambient air. The risk of opportunistic infection from these viruses can be increased in mechanically ventilated patients. The present study evaluates the feasibility of detecting airborne respiratory viruses in mechanically ventilated patients using a novel sample collection method involving ventilator filters.MethodsWe collected inspiratory and expiratory filters from the ventilator circuits of mechanically ventilated patients in an intensive care unit over a 14-month period. To evaluate whether we could detect respiratory viruses collected in these filters, we performed a reverse transcription polymerase chain reaction on the extracted filter membrane with primers specific for rhinovirus, respiratory syncytial virus, influenza virus A and B, parainfluenza virus (type 1, 2 and 3) and human metapneumovirus. For each patient, we also performed a full virology screen (virus particles, antibody titres and virus-induced biomarkers) on respiratory samples (nasopharyngeal swab, tracheal aspirate or bronchoalveolar fluid) and blood samples.ResultsRespiratory viruses were detected in the ventilator filters of nearly half the patients in the study cohort (n = 33/70). The most common virus detected was influenza A virus (n = 29). There were more viruses detected in the inspiratory filters (n = 18) than in the expiratory filters (n = 15). A third of the patients with a positive virus detection in the ventilator filters had a hospital laboratory confirmed viral infection. In the remaining cases, the detected viruses were different from viruses already identified in the same patient, suggesting that these additional viruses come from the ambient air or from cross-contamination (staff or visitors). In patients in whom new viruses were detected in the ventilator filters, there was no evidence of clinical signs of an active viral infection. Additionally, the levels of virus-induced biomarker in these patients were not statistically different from those of non-infected patients (p = 0.33).ConclusionsRespiratory viruses were present within the ventilator circuits of patients receiving mechanical ventilation. Although no adverse clinical effect was evident in these patients, further studies are warranted, given the small sample size of the study and the recognition that ventilated patients are potentially susceptible to opportunistic infection from airborne respiratory viruses.

The value of T cell spot test of tuberculosis infection and inflammatory indicators for diagnosis of active tuberculosis in patients with fever of unknown origin

Objective To evaluate the value of T cell spot test of tuberculosis infection(T-SPOT.TB) and inflammatory indicators for diagnosis of active tuberculosis in patients with fever of unknown origin (FUO). Methods Patients with FUO in Tongji Hospital from Jan 1st 2014 to Feb 28th 2015 were retrospectively enrolled, and general condition, laboratory examination including T-SPOT.TB, blood routine test, procalcitonin (PCT), high sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), serum ferritin (SF) and final diagnosis were collected and analyzed. Results A total of 395 hospitalized patients with FUO were retrospectively enrolled into this study, among which there were 36 (9.11%) confirmed active tuberculosis (including 7 pulmonary cases and 29 extra-pulmonary cases), 189 (47.85%) bacterial infections, 50 (12.66%) viral infections, 4 (6.32%) fungal infections, 20 (5.06%) neoplastic diseases, 51(12.91%) autoimmune diseases, 25 (6.32%) other diseases. While 20 (5.06%) patients remained un-diagnosed. The sensitivity of T-SPOT.TB for the diagnosis of active TB in patients with FUO was 80.56% (95%CI: 63.43%-91.20%), and the specificity was 83.57% (95%CI: 79.23%-87.16%). The positive predictive value was 32.95% (95%CI: 23.52%-43.89%), and the negative predictive value was 97.72% (95%CI: 95.16%-99.00%). There were significant differences in positive LDH levels (187[141, 255] U/L vs 209[160, 343] U/L) and SF levels (296.2[191.3, 494.8] g/L vs 528.1[281.1, 1 022.0] μg/L) between active tuberculosis group and bacterial infection group (χ2=77.692, H=13.442, H=16.142, all P<0.05). The combination of T-SPOT.TB and multiple inflammatory indicators obtained most valuable efficiency (AUC=0.866) for TB diagnosis. Similarly, there were significant differences in positive ESR (31[15, 78] mm/1 h vs 10[6, 19] mm/1 h), ratio of neutrophil granulocytes ([71.17±12.59]% vs [57.08±20.38]%) between active tuberculosis group and viral infection group (H=32.797, F=6.171, all P<0.05). The combination acquired most valuable efficiency (AUC=0.929). Conclusions For patients with FUO, T-SPOT.TB combined with inflammatory indicators are valuable for the diagnosis of active tuberculosis. Key words: Fever of unknown origin; T-SPOT.TB test; Inflammatory indicators; Active tuberculosis

Abstract OT1-03-06: Phase IB/II clinical trial to evaluate safety and efficacy of tucatinib in combination with palbociclib and letrozole in patients with hormone receptor positive and HER2-positive metastatic breast cancer

Abstract Breast cancers overexpressing HER2-oncogene and hormone receptors (HR) represent therapeutic challenge because of a bi-directional cross-talk between HR and HER2 pathways leading to tumor progression and drug resistance. There is a strong rationale for evaluation of novel targeted drug combinations in this breast cancer subtype. We designed a phase IB /II clinical trial to test the combination of novel oral HER2 small molecule inhibitor tucatinib with CDK4/6 inhibitor palbociclib and aromatase inhibitor letrozole in patients with HR+/HER2+ metastatic breast cancer (NCT03054363). In addition to the rationale for the synergy of targeting HR, HER2 and CDK4/6 pathways simultaneously in this disease setting and its potential for anti-tumor efficacy, we propose this novel combination of three oral agents, if well tolerated, will be highly patient-centered as an effective non-chemotherapy based regimen for treatment of HR+/HER2+ breast cancer. This multicenter clinical trial is conducted through the Academic Breast Cancer Consortium (ABRCC), with the University of Colorado Cancer Center as the lead site. Target enrollment: 40 patients (20 patients in phase IB and 20 patients in phase II part). Main inclusion criteria: 1. HR+/HER2+ locally advanced unresectable / metastatic breast cancer 2. Measurable or evaluable disease. Bone only disease is allowed. 3. Subjects without brain metastases are eligible; subjects with untreated asymptomatic CNS metastases not needing immediate local therapy, and subjects with stable brain metastases previously treated with radiation therapy or surgery are eligible 4. ECOG 0-1 5. Postmenopausal women, or premenopausal women on ovarian suppression 6. Prior treatments: - At least two approved HER2-targeted agents (trastuzumab, pertuzumab, or TDM-1) at any time in the course of the disease - At least 1 line of HER2-targeted therapy in the metastatic setting (with the exception of asymptomatic subjects with oligometastatic or bone / soft tissue only disease who, on investigator opinion, are appropriate for a front line single agent anti-endocrine therapy per NCCN guidelines) - Up to 2 lines of prior endocrine therapy in the metastatic setting are allowed 7. Adequate organ and marrow function Main exclusion criteria: 1. Previously treated progressing brain metastases 2. Brain metastases and contraindications to undergo contrast brain MRI 3. Toxicities of prior cancer therapies that have not resolved to grade 1 or less, except peripheral neuropathy, which must have resolved to grade 2 or less, and alopecia 4. Previous treatment with EGFR or HER2 tyrosine kinase inhibitors or CDK4/6 inhibitors 5. Systemic anti-cancer therapy or radiation within 2 weeks of the first dose of study drugs 6. Active bacterial, fungal or viral infections, hepatitis B, C, or HIV 7. Clinically significant cardio-vascular disease Primary objectives: - Phase IB: safety and tolerability of combination therapy - Phase II: efficacy by PFS Exploratory assessment of biomarkers of resistance and response will be performed in the blood and biopsy samples Study contact: Elena Shagisultanova, MD, PhD, elena.shagisultanova@ucdenver.edu Citation Format: Shagisultanova E, Diamond J, Stopeck A, Pusztai L, O'Regan R, Gradishar W, Brown-Glaberman U, Chalasani P, McSpadden T, Borakove M, Shedin T, Kabos P, Borges V. Phase IB/II clinical trial to evaluate safety and efficacy of tucatinib in combination with palbociclib and letrozole in patients with hormone receptor positive and HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-03-06.

Highly Sensitive Virome Capture Sequencing Technique VirCapSeq-VERT Identifies Partial Noncoding Sequences but no Active Viral Infection in Cutaneous T-Cell Lymphoma

Highly Sensitive Virome Capture Sequencing Technique VirCapSeq-VERT Identifies Partial Noncoding Sequences but no Active Viral Infection in Cutaneous T-Cell Lymphoma