Browsing by Subject "DNA, Viral"
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Item Open Access A functional variant at miRNA-122 binding site in IL-1a 3' UTR predicts risk of recurrence in patients with oropharyngeal cancer.(Oncotarget, 2016-06) Wang, Chengyuan; Sturgis, Erich M; Chen, Xingming; Wei, Qingyi; Li, GuojunIL-1a, an important regulator of immune and inflammation responses, has been implicated in cancer development and prognosis. An insertion (Ins)/deletion (Del) polymorphism (IL-1a rs3783553) in the 3' UTR of IL-1a may disrupt a binding site for miRNA-122 and may affect its transcription level. Thus, this polymorphism may cause interindividual variation in immune and inflammation responses and thus may lead to different susceptibility to treatment response and prognosis of such patients. We evaluated the association of IL-1a rs3783553 polymorphism with risk of recurrence of squamous cell carcinoma of the oropharynx (SCCOP) in a cohort of 1008 patients. Log-rank test and univariate and multivariable Cox models were used to evaluate associations. Compared with patients with Del/Del homozygous genotype, the patients with Ins/Del+Ins/Ins variant genotypes had worse disease-free survival (log-rank P < 0.0001) and increased risk of SCCOP recurrence (HR, 2.4, 95% CI, 1.7-3.3) after multivariable adjustment. Furthermore, among patients with HPV16-positive tumors, the patients with Ins/Del+Ins/Ins variant genotypes of the IL-1a polymorphism had worse disease-free survival (log-rank P < 0.0001) and much higher recurrence risk than those with Del/Del homozygous genotype of this polymorphism (HR, 16.3, 95% CI, 5.0-52.7). Our findings suggest that IL-1a rs3783553 polymorphism may modulate the risk of SCCOP recurrence in patients, particularly for patients with HPV16-positive tumors. However, larger studies are needed to validate these results.Item Open Access A Lysine Residue Essential for Geminivirus Replication Also Controls Nuclear Localization of the Tomato Yellow Leaf Curl Virus Rep Protein.(Journal of virology, 2019-05) Maio, Francesca; Arroyo-Mateos, Manuel; Bobay, Benjamin G; Bejarano, Eduardo R; Prins, Marcel; van den Burg, Harrold AGeminiviruses are single-stranded DNA (ssDNA) viruses that infect a wide range of plants. To promote viral replication, geminiviruses manipulate the host cell cycle. The viral protein Rep is essential to reprogram the cell cycle and then initiate viral DNA replication by interacting with a plethora of nuclear host factors. Even though many protein domains of Rep have been characterized, little is known about its nuclear targeting. Here, we show that one conserved lysine in the N-terminal part of Rep is pivotal for nuclear localization of the Rep protein from Tomato yellow leaf curl virus (TYLCV), with two other lysines also contributing to its nuclear import. Previous work had identified that these residues are essential for Rep from Tomato golden mosaic virus (TGMV) to interact with the E2 SUMO-conjugating enzyme (SCE1). We here show that mutating these lysines leads to nuclear exclusion of TYLCV Rep without compromising its interaction with SCE1. Moreover, the ability of TYLCV Rep to promote viral DNA replication also depends on this highly conserved lysine independently of its role in nuclear import of Rep. Our data thus reveal that this lysine potentially has a broad role in geminivirus replication, but its role in nuclear import and SCE1 binding differs depending on the Rep protein examined.IMPORTANCE Nuclear activity of the replication initiator protein (Rep) of geminiviruses is essential for viral replication. We now define that one highly conserved lysine is important for nuclear import of Rep from three different begomoviruses. To our knowledge, this is the first time that nuclear localization has been mapped for any geminiviral Rep protein. Our data add another key function to this lysine residue, besides its roles in viral DNA replication and interaction with host factors, such as the SUMO E2-conjugating enzyme.Item Open Access CCR5-Δ32 Heterozygosity, HIV-1 Reservoir Size, and Lymphocyte Activation in Individuals Receiving Long-term Suppressive Antiretroviral Therapy.(The Journal of infectious diseases, 2016-03) Henrich, Timothy J; Hanhauser, Emily; Harrison, Linda J; Palmer, Christine D; Romero-Tejeda, Marisol; Jost, Stephanie; Bosch, Ronald J; Kuritzkes, Daniel RWe conducted a case-controlled study of the associations of CCR5-Δ32 heterozygosity with human immunodeficiency virus type 1 (HIV-1) reservoir size, lymphocyte activation, and CCR5 expression in 114 CCR5(Δ32/WT) and 177 wild-type CCR5 AIDS Clinical Trials Group participants receiving suppressive antiretroviral therapy. Overall, no significant differences were found between groups for any of these parameters. However, higher levels of CCR5 expression correlated with lower amounts of cell-associated HIV-1 RNA. The relationship between CCR5-Δ32 heterozygosity, CCR5 expression, and markers of HIV-1 persistence is likely to be complex and may be influenced by factors such as the duration of ART.Item Open Access Conserved Structural Motif Identified in Peptides That Bind to Geminivirus Replication Protein Rep.(Biochemistry, 2021-09) Ascencio-Ibáñez, J Trinidad; Bobay, Benjamin GThe geminivirus replication protein, Rep, has long been recognized as a high-value target for control of geminivirus infections as this protein is highly conserved and essential for viral replication and proliferation. In addition, inhibition of viral replication has been pursued through various antiviral strategies with varying degrees of success, including inhibitory peptides that target Rep. While much effort has centered around sequence characterization of the Rep protein and inhibitory peptides, detailed structural analysis has been missing. This study computationally investigated the presence of common structural features within these inhibitory peptides and if these features could inform if a particular peptide will bind Rep and/or interfere with viral replication. Molecular dynamics simulations of the inhibitory peptide library showed that simply possessing stable structural features does not inform interference of viral replication regardless of the binding of Rep. Additionally, nearly all known Rep inhibitory peptides sample a conserved β-sheet structural motif, possibly informing structure-function relationships in binding Rep. In particular, two peptides (A22 and A64) characterized by this structural motif were computationally docked against a wide variety of geminivirus Rep proteins to determine a mechanism of action. Computational docking revealed these peptides utilize a common Rep protein sequence motif for binding, HHN-x1/2-Q. The results identified residues in both Rep and the inhibitory peptides that play a significant role in the interaction, establishing the foundation for a rational structure-based design approach for the construction of both broadly reactive and geminivirus species-specific inhibitors.Item Open Access Human Herpes Virus 8 in HIV-1 infected individuals receiving cancer chemotherapy and stem cell transplantation.(PloS one, 2018-01) Hogan, Louise E; Hanhauser, Emily; Hobbs, Kristen S; Palmer, Christine D; Robles, Yvonne; Jost, Stephanie; LaCasce, Anne S; Abramson, Jeremy; Hamdan, Ayad; Marty, Francisco M; Kuritzkes, Daniel R; Henrich, Timothy JBackground
Human Herpes Virus 8 (HHV8) can cause Kaposi's Sarcoma (KS) in immunosuppressed individuals. However, little is known about the association between chemotherapy or hematopoietic stem cell transplantation (HSCT), circulating HHV8 DNA levels, and clinical KS in HIV-1-infected individuals with various malignancies. Therefore, we examined the associations between various malignancies, systemic cancer chemotherapy, T cell phenotypes, and circulating HHV8 DNA in 29 HIV-1-infected participants with concomitant KS or other cancer diagnoses.Methods
We quantified HHV8 plasma viral loads and cell-associated HHV8 DNA and determined the relationship between circulating HHV8 DNA and lymphocyte counts, and markers of early and late lymphocyte activation, proliferation and exhaustion.Results
There were no significant differences in plasma HHV8 DNA levels between baseline and post-chemotherapy time points or with the presence or absence of clinical KS. However, in two participants circulating HHV8 DNA increased following treatment for KS or HSCT for lymphoma,. We observed an approximately 2-log10 reduction in plasma HHV8 DNA in an individual with KS and multicentric Castleman disease following rituximab monotherapy. Although individuals with clinical KS had lower mean CD4+ T cell counts and percentages as expected, there were no significant associations with these factors and plasma HHV8 levels. We identified increased proportions of CD8+ and CD4+ T cells expressing CD69 (P = 0.01 & P = 0.04 respectively), and increased CD57 expression on CD4+ T cells (P = 0.003) in participants with detectable HHV8.Conclusion
These results suggest there is a complex relationship between circulating HHV8 DNA and tissue-based disease in HIV-1 and HHV8 co-infected individuals with various malignancies.Item Open Access Human Immunodeficiency Virus Type 1 Persistence Following Systemic Chemotherapy for Malignancy.(The Journal of infectious diseases, 2017-07) Henrich, Timothy J; Hobbs, Kristen S; Hanhauser, Emily; Scully, Eileen; Hogan, Louise E; Robles, Yvonne P; Leadabrand, Kaitlyn S; Marty, Francisco M; Palmer, Christine D; Jost, Stephanie; Körner, Christian; Li, Jonathan Z; Gandhi, Rajesh T; Hamdan, Ayad; Abramson, Jeremy; LaCasce, Ann S; Kuritzkes, Daniel RBackground
Systemic chemotherapies for various malignancies have been shown to significantly, yet transiently, decrease numbers of CD4+ T lymphocytes, a major reservoir for human immunodeficiency virus type 1 (HIV-1) infection. However, little is known about the impact of cytoreductive chemotherapy on HIV-1 reservoir dynamics, persistence, and immune responses.Methods
We investigated the changes in peripheral CD4+ T-cell-associated HIV-1 DNA and RNA levels, lymphocyte activation, viral population structure, and virus-specific immune responses in a longitudinal cohort of 15 HIV-1-infected individuals receiving systemic chemotherapy or subsequent autologous stem cell transplantation for treatment of hematological malignancies and solid tumors.Results
Despite a transient reduction in CD4+ T cells capable of harboring HIV-1, a 1.7- and 3.3-fold increase in mean CD4+ T-cell-associated HIV-1 RNA and DNA, respectively, were observed months following completion of chemotherapy in individuals on antiretroviral therapy. We also observed changes in CD4+ T-cell population diversity and clonal viral sequence expansion during CD4+ T-cell reconstitution following chemotherapy cessation. Finally, HIV-1 DNA was preferentially, and in some cases exclusively, detected in cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-responsive CD4+ T cells following chemotherapy.Conclusions
Expansion of HIV-infected CMV/EBV-specific CD4 + T cells may contribute to maintenance of the HIV DNA reservoir following chemotherapy.Item Open Access Postnatal cytomegalovirus exposure in infants of antiretroviral-treated and untreated HIV-infected mothers.(Infect Dis Obstet Gynecol, 2014) Meyer, Sarah A; Westreich, Daniel J; Patel, Emily; Ehlinger, Elizabeth P; Kalilani, Linda; Lovingood, Rachel V; Denny, Thomas N; Swamy, Geeta K; Permar, Sallie RHIV-1 and CMV are important pathogens transmitted via breastfeeding. Furthermore, perinatal CMV transmission may impact growth and disease progression in HIV-exposed infants. Although maternal antiretroviral therapy reduces milk HIV-1 RNA load and postnatal transmission, its impact on milk CMV load is unclear. We examined the relationship between milk CMV and HIV-1 load (4-6 weeks postpartum) and the impact of antiretroviral treatment in 69 HIV-infected, lactating Malawian women and assessed the relationship between milk CMV load and postnatal growth in HIV-exposed, breastfed infants through six months of age. Despite an association between milk HIV-1 RNA and CMV DNA load (0.39 log(10) rise CMV load per log(10) rise HIV-1 RNA load, 95% CI 0.13-0.66), milk CMV load was similar in antiretroviral-treated and untreated women. Higher milk CMV load was associated with lower length-for-age (-0.53, 95% CI: -0.96, -0.10) and weight-for-age (-0.40, 95% CI: -0.67, -0.13) Z-score at six months in exposed, uninfected infants. As the impact of maternal antiretroviral therapy on the magnitude of postnatal CMV exposure may be limited, our findings of an inverse relationship between infant growth and milk CMV load highlight the importance of defining the role of perinatal CMV exposure on growth faltering of HIV-exposed infants.Item Open Access Potent functional antibody responses elicited by HIV-I DNA priming and boosting with heterologous HIV-1 recombinant MVA in healthy Tanzanian adults.(PLoS One, 2015) Joachim, Agricola; Nilsson, Charlotta; Aboud, Said; Bakari, Muhammad; Lyamuya, Eligius F; Robb, Merlin L; Marovich, Mary A; Earl, Patricia; Moss, Bernard; Ochsenbauer, Christina; Wahren, Britta; Mhalu, Fred; Sandström, Eric; Biberfeld, Gunnel; Ferrari, Guido; Polonis, Victoria RUNLABELLED: Vaccine-induced HIV antibodies were evaluated in serum samples collected from healthy Tanzanian volunteers participating in a phase I/II placebo-controlled double blind trial using multi-clade, multigene HIV-DNA priming and recombinant modified vaccinia Ankara (HIV-MVA) virus boosting (HIVIS03). The HIV-DNA vaccine contained plasmids expressing HIV-1 gp160 subtypes A, B, C, Rev B, Gag A, B and RTmut B, and the recombinant HIV-MVA boost expressed CRF01_AE HIV-1 Env subtype E and Gag-Pol subtype A. While no neutralizing antibodies were detected using pseudoviruses in the TZM-bl cell assay, this prime-boost vaccination induced neutralizing antibodies in 83% of HIVIS03 vaccinees when a peripheral blood mononuclear cell (PBMC) assay using luciferase reporter-infectious molecular clones (LucR-IMC) was employed. The serum neutralizing activity was significantly (but not completely) reduced upon depletion of natural killer (NK) cells from PBMC (p=0.006), indicating a role for antibody-mediated Fcγ-receptor function. High levels of antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies against CRF01_AE and/or subtype B were subsequently demonstrated in 97% of the sera of vaccinees. The magnitude of ADCC-mediating antibodies against CM235 CRF01_AE IMC-infected cells correlated with neutralizing antibodies against CM235 in the IMC/PBMC assay. In conclusion, HIV-DNA priming, followed by two HIV-MVA boosts elicited potent ADCC responses in a high proportion of Tanzanian vaccinees. Our findings highlight the potential of HIV-DNA prime HIV-MVA boost vaccines for induction of functional antibody responses and suggest this vaccine regimen and ADCC studies as potentially important new avenues in HIV vaccine development. TRIAL REGISTRATION: Controlled-Trials ISRCTN90053831 The Pan African Clinical Trials Registry ATMR2009040001075080 (currently PACTR2009040001075080).Item Open Access Vaginal Self-Sampling for Human Papillomavirus Infection as a Primary Cervical Cancer Screening Tool in a Haitian Population.(Sex Transm Dis, 2015-11) Boggan, Joel C; Walmer, David K; Henderson, Gregory; Chakhtoura, Nahida; McCarthy, Schatzi H; Beauvais, Harry J; Smith, Jennifer SBACKGROUND: Human papillomavirus (HPV) testing as primary cervical cancer screening has not been studied in Caribbean women. We tested vaginal self-collection versus physician cervical sampling in a population of Haitian women. METHODS: Participants were screened for high-risk HPV with self-performed vaginal and clinician-collected cervical samples using Hybrid Capture 2 assays (Qiagen, Gaithersburg, MD). Women positive by either method then underwent colposcopy with biopsy of all visible lesions. Sensitivity and positive predictive value were calculated for each sample method compared with biopsy results, with κ statistics performed for agreement. McNemar tests were performed for differences in sensitivity at ≥cervical intraepithelial neoplasia (CIN)-I and ≥CIN-II. RESULTS: Of 1845 women screened, 446 (24.3%) were HPV positive by either method, including 105 (5.7%) only by vaginal swab and 53 (2.9%) only by cervical swab. Vaginal and cervical samples were 91.4% concordant (κ = 0.73 [95% confidence interval, 0.69-0.77], P < 0.001). Overall, 133 HPV-positive women (29.9%) had CIN-I, whereas 32 (7.2%) had ≥CIN-II. The sensitivity of vaginal swabs was similar to cervical swabs for detecting ≥CIN-I (89.1% vs. 87.9%, respectively; P = 0.75) lesions and ≥CIN-II disease (87.5% vs. 96.9%, P = 0.18). Eighteen of 19 cases of CIN-III and invasive cancer were found by both methods. CONCLUSIONS: Human papillomavirus screening via self-collected vaginal swabs or physician-collected cervical swabs are feasible options in this Haitian population. The agreement between cervical and vaginal samples was high, suggesting that vaginal sample-only algorithms for screening could be effective for improving screening rates in this underscreened population.