Genetics and Genomics Commons^™

Species D Adenoviruses As Oncolytics Against B-Cell Cancers, Christopher Y. Chen, Julien S. Senac, Eric A. Weaver, Shannon M. May, Diane F. Jelinek, Philip Greipp, Thomas Witzig, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Purpose: Oncolytic viruses are self-amplifying anticancer agents that make use of the natural ability of viruses to kill cells. Adenovirus serotype 5 (Ad5) has been extensively tested against solid cancers, but less so against B-cell cancers because these cells do not generally express the coxsackie and adenoviral receptor (CAR). To determine whether other adenoviruses might have better potency, we "mined" the adenovirus virome of 55 serotypes for viruses that could kill B-cell cancers.

Experimental Design: Fifteen adenoviruses selected to represent Ad species B, C, D, E, and F were tested in vitro against cell lines and primary patient B-cell cancers …

Association Between Chronic Liver And Colon Inflammation During The Development Of Murine Syngeneic Graft-Versus-Host Disease, Jason Anthony Brandon, Jacqueline Perez-Rodriguez, C. Darrell Jennings, Donald A. Cohen, Vishal J. Sindhava, Subbarao Bondada, Alan M. Kaplan, J. Scott Bryson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The murine model of cyclosporine A (CsA)-induced syngeneic graft-versus-host disease (SGVHD) is a bone marrow (BM) transplantation model that develops chronic colon inflammation identical to other murine models of CD4⁺ T cell-mediated colitis. Interestingly, SGVHD animals develop chronic liver lesions that are similar to the early peribiliary inflammatory stages of clinical chronic liver disease, which is frequently associated with inflammatory bowel disease (IBD). Therefore, studies were initiated to investigate the chronic liver inflammation that develops in the SGVHD model. To induce SGVHD, mice were lethally irradiated, reconstituted with syngeneic BM, and treated with CsA. All of the SGVHD animals …

Regulation Of Pim1 Under Hypoxia In Prostate Cancer, Eva Sahakian

Loma Linda University Electronic Theses, Dissertations & Projects

A defining characteristic of solid tumors is the capacity to divide and spread under conditions of nutrient deprivation and limited oxygen availability. These microenvironmental stresses arise from structural abnormalities in tumor vessels that lead to aberrant microcirculation. Hypoxia acts as a physiological “selection pressure” in the progression of cancer by activating pathways and enhancing the expression of specific genes in tumor cells which eventually diminish their apoptotic potential. Ultimately, hypoxic microenvironment functions as a “stress factor”, selecting cells with the ability to survive and divide under anoxic conditions. The members of the PIM family of cytoplasmic serine threonine kinases are …

A New Tumor Suppressor Gene Candidate Regulated By The Non-Coding Rna Pca3 In Human Prostate Cancer, Alessandro K. Lee

Dissertations and Theses (Open Access)

Prostate cancer is the second leading cause of cancer-related death and the most common non-skin cancer in men in the USA. Considerable advancements in the practice of medicine have allowed a significant improvement in the diagnosis and treatment of this disease and, in recent years, both incidence and mortality rates have been slightly declining. However, it is still estimated that 1 man in 6 will be diagnosed with prostate cancer during his lifetime, and 1 man in 35 will die of the disease.

In order to identify novel strategies and effective therapeutic approaches in the fight against prostate cancer, it …

Plasmid Injection And Application Of Electric Pulses Alter Endogenous Mrna And Protein Expression In B16.F10 Mouse Melanomas, L. C. Heller, Y. L. Cruz, B. Ferraro, H. Yang, R. Heller

Bioelectrics Publications

The application of electric pulses to tissues causes cell membrane destabilization, allowing exogenous molecules to enter the cells. This delivery technique can be used for plasmid gene therapy. Reporter gene expression after plasmid delivery with eight representative published protocols was compared in B16.F10 mouse melanoma tumors. This expression varied significantly based on the pulse parameters utilized for delivery. To observe the possible influence of plasmid injection and/or pulse application on endogenous gene expression, levels of stress-related mRNAs 4 and 24 h after delivery were determined by PCR array. Increases in mRNA levels for several inflammatory chemokines and cytokines were observed …

Chlorella Viruses Encode Most, If Not All, Of The Machinery To Glycosylate Their Glycoproteins Independent Of The Endoplasmic Reticulum And Golgi, James L. Van Etten, James Gurnon, Giane M. Yanai-Balser, David Dunigan, Michael V. Graves

Nebraska Center for Virology: Faculty Publications

In contrast to all other viruses that use the host machinery located in the endoplasmic reticulum and Golgi to glycosylate their glycoproteins, the large dsDNA-containing chlorella viruses encode most, if not all, of the components to glycosylate their major capsid proteins. Furthermore, all experimental results indicate that glycosylation occurs independent of the endoplasmic reticulum and Golgi. (Review article)

Neuroaids In Africa, Kevin Robertson, Jeff Liner, James Hakim, Jean-Louis Sankalé, Igor Grant, Scott Letendre, David Clifford, Amadou Gallo Diop, Assan Jaye, Georgette Kanmogne, Alfred Njamnshi, T. Dianne Langford, Tufa Gemechu Weyessa, Charles Wood, Mwanza Banda, Mina Hosseinipour, Ned Sacktor, Noeline Nakasuja, Paul Bangirana, Robert Paul, John Joska, Joseph Wong, Michael Boivin, Penny Holding, Betsy Kammerer, Annelies Van Rie, Prudence Ive, Avindra Nath, Kathy Lawler, Clement Adebamowo, Walter Royal Iii, Jeymohan Joseph

Nebraska Center for Virology: Faculty Publications

In July 2009, the Center for Mental Health Research on AIDS at the National Institute of Mental Health organized and supported the meeting “NeuroAIDS in Africa.” This meeting was held in Cape Town, South Africa, and was affiliated with the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention. Presentations began with an overview of the epidemiology of HIV in sub-Saharan Africa, the molecular epidemiology of HIV, HIV-associated neurocognitive disorders (HANDs), and HAND treatment. These introductory talks were followed by presentations on HAND research and clinical care in Botswana, Cameroon, Ethiopia, The Gambia, Kenya, Malawi, Nigeria, Senegal, South Africa, Uganda, …

Functional Properties Of The Hiv-1 Subtype C Envelope Glycoprotein Associated With Mother-To-Child Transmission, Hong Zhang, Marzena Rola, John T. West, Damien C. Tully, Piotr Kubis, Jun He, Chipepo Kankasa, Charles Wood

Nebraska Center for Virology: Faculty Publications

Understanding the properties of viruses capable of establishing infection during perinatal transmission of HIV-1 is critical for designing effective means of limiting transmission. We previously demonstrated that the newly transmitted viruses (in infant) were more fit in growth, as imparted by their envelope glycoproteins, than those in their corresponding mothers. Here, we further characterized the viral envelope glycoproteins from six mother-infant transmission pairs and determined whether any specific envelope functions correlate with HIV-1 subtype C perinatal transmission. We found that most newly transmitted viruses were less susceptible to neutralization by their maternal plasma compared to contemporaneous maternal viruses. However, the …

Chronology And Evolution Of The Hiv-1 Subtype C Epidemic In Ethiopia, Damien C. Tully, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To reconstruct the onset date and evolutionary history of the HIV-1 subtype C epidemic in Ethiopia - one of the earliest recorded subtype C epidemics in the world.

Design—HIV-1 C env sequences with a known sampling year isolated from HIV-1 positive patients from Ethiopia between 1984 and 2003.

Methods—Evolutionary parameters including origin and demographic growth patterns were estimated using a Bayesian coalescent-based approach under either strict or relaxed molecular clock models.

Results—Bayesian evolutionary analysis indicated a most recent common ancestor date of 1965 with three distinct epidemic growth phases. Regression analysis of root-to-tip distances revealed a highly similar estimate for …

Enhancement Of Autophagy During Lytic Replication By The Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator, Hui-Ju Wen, Zhilong Yang, You Zhou, Charles Wood

Nebraska Center for Virology: Faculty Publications

Autophagy is one of two major degradation systems in eukaryotic cells. The degradation mechanism of autophagy is required to maintain the balance between the biosynthetic and catabolic processes and also contributes to defense against invading pathogens. Recent studies suggest that a number of viruses can evade or subvert the host cell autophagic pathway to enhance their own replication. Here, we investigated the effect of autophagy on the KSHV (Kaposi’s sarcoma-associated herpesvirus) life cycle. We found that the inhibition of autophagy reduces KSHV lytic reactivation from latency, and an enhancement of autophagy can be detected during KSHV lytic replication. In addition, …

Protection Against Mucosal Shiv Challenge By Peptide And Helper-Dependent Adenovirus Vaccines, Eric A. Weaver, Pramod N. Nehete, Bharti P. Nehete, Stephanie J. Buchl, Donna Palmer, David C. Montefiori, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env) peptides and first generation adenovirus serotype 5 (FG-Ad5) vaccines expressing the same peptides were immunized intramuscularly three times with helperdependent adenovirus (HD-Ad) vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5- immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than in …

Comparison Of Replication-Competent, First Generation, And Helper-Dependent Adenoviral Vaccines, Eric A. Weaver, Pramod N. Nehete, Stephanie S. Buchl, Julien S. Senac, Donna Palmer, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

All studies using human serotype 5 Adenovirus (Ad) vectors must address two major obstacles: safety and the presence of pre-existing neutralizing antibodies. Helper-Dependent (HD) Ads have been proposed as alternative vectors for gene therapy and vaccine development because they have an improved safety profile. To evaluate the potential of HD-Ad vaccines, we compared replication-competent (RC), first-generation (FG) and HD vectors for their ability to induce immune responses in mice. We show that RC-Ad5 and HD-Ad5 vectors generate stronger immune responses than FG-Ad5 vectors. HD-Ad5 vectors gave lower side effects than RC or FG-Ad, producing lower levels of tissue damage and …

Accumulation Of Rhodopsin In Late Endosomes Triggers Photoreceptor Cell Degeneration, Yashodhan Chinchore, Amitavo Mitra, Patrick J. Dolph, Norbert Perrimon

Dartmouth Scholarship

Progressive retinal degeneration is the underlying feature of many human retinal dystrophies. Previous work using Drosophila as a model system and analysis of specific mutations in human rhodopsin have uncovered a connection between rhodopsin endocytosis and retinal degeneration. In these mutants, rhodopsin and its regulatory protein arrestin form stable complexes, and endocytosis of these complexes causes photoreceptor cell death. In this study we show that the internalized rhodopsin is not degraded in the lysosome but instead accumulates in the late endosomes. Using mutants that are defective in late endosome to lysosome trafficking, we were able to show that rhodopsin accumulates …

X4 Human Immunodeficiency Virus Type 1 Gp120 Down-Modulates Expression And Immunogenicity Of Codelivered Antigens, Avi-Hai Hovav, Michael Santosuosso, Maytal Bivas-Benita, Andre Plair, Alex Cheng, Mazal Elnekave, Elda Righi, Tao Chen, Satoshi Kashiwagi, Michael W. Panas, Shi-Hua Xiang, Karina Furmanov, Norman L. Letvin, Mark C. Poznansky

Nebraska Center for Virology: Faculty Publications

In order to increase the immune breadth of human immunodeficiency virus (HIV) vaccines, strategies such

as immunization with several HIV antigens or centralized immunogens have been examined. HIV-1 gp120

protein is a major immunogen of HIV and has been routinely considered for inclusion in both present and

future AIDS vaccines. However, recent studies proposed that gp120 interferes with the generation of immune

response to codelivered antigens. Here, we investigate whether coimmunization with plasmid-encoded gp120

alters the immune response to other coadministered plasmid encoded antigens such as luciferase or ovalbumin

in a mouse model. We found that the presence of gp120 …

Identification And Characterization Of A New Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator (Rta)- Responsive Element Involved In Rta-Mediated Transactivation, Hui-Ju Wen, Veenu Minhas, Charles Wood

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) replication and transcription activator (RTA) is well established as a key transcriptional activator that regulates the KSHV life cycle from latency to lytic replication. It is expressed immediately after infection and activates a number of viral genes leading to virus replication. The RTA-responsive element (RRE) in the RTA target gene promoters is critical for RTA to mediate this transactivation. A number of non-conserved RREs have been identified in various RTA-responsive promoters, and AT-rich sequences have been proposed to serve as RTA targets, but no consensus RRE sequence has been identified so far. Two nonconserved RREs (RRE1 …

Use Of Average Mutual Information For Studying Changes In Hiv Populations, Khalid Sayood, Federico Hoffman, Charles Wood

Nebraska Center for Virology: Faculty Publications

Average mutual information (AMI) has been used in a number of applications in bioinformatics. In this paper we present its use to study genetic changes in populations; in particular populations of HIV viruses. Disease progression of HIV-1 infection in infants can be rapid resulting in death within the the first year, or slow, allowing the infant to survive beyond the first year. We study the development of rapid and slow progressing HIV population using AMI charts based on average mutual information among amino acids in the env gene from a population of 1142 clones derived from seven infants with slow …

Comparison Of Replication-Competent, First Generation, And Helper-Dependent Adenoviral Vaccines, Eric A. Weaver, Pramod N. Nehete, Stephanie S. Buchl, Julien S. Senac, Donna Palmer, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

All studies using human serotype 5 Adenovirus (Ad) vectors must address two major obstacles: safety and the presence of pre-existing neutralizing antibodies. Helper-Dependent (HD) Ads have been proposed as alternative vectors for gene therapy and vaccine development because they have an improved safety profile. To evaluate the potential of HD-Ad vaccines, we compared replication-competent (RC), first-generation (FG) and HD vectors for their ability to induce immune responses in mice. We show that RC-Ad5 and HD-Ad5 vectors generate stronger immune responses than FG-Ad5 vectors. HD-Ad5 vectors gave lower side effects than RC or FG-Ad, producing lower levels of tissue damage and …

The Association Of Human Leukocyte Antigen(Hla) Alleles And Type 2 Diabetes Mellitus (T2dm) Among Mexican Americans (Ma), Kantibhai Motiram Patel

Open Access Theses & Dissertations

The epidemic of type 2 diabetes mellitus (T2DM) is ranked as a major public health priority across the United States and especially in the El Paso, Texas region. The risk for the development of T2DM is greater in minority groups, particularly among Mexican Americans (MA) who comprise approximately 78% of El Paso's population. The growing incidence of T2DM in this group is typically attributed to increase in weight (obesity). The incidence of diabetes may also be influenced by genetic factors that are unique to this group. Several earlier studies have identified genetic markers for type 1 diabetes mellitus (T1DM). These …

Human Ubc9 Contributes To Production Of Fully Infectious Human Immunodeficiency Virus Type 1 Virions, Tareq Jaber, Christopher R. Bohl, Gentry L. Lewis, Charles Wood, John T. West Jr., Robert A. Weldon Jr.

Nebraska Center for Virology: Faculty Publications

Ubc9 was identified as a cellular protein that interacts with the Gag protein of Mason-Pfizer monkey virus. We show here that Ubc9 also interacts with the human immunodeficiency virus type 1 (HIV-1) Gag protein and that their interaction is important for virus replication. Gag was found to colocalize with Ubc9 predominantly at perinuclear puncta. While cells in which Ubc9 expression was suppressed with RNA interference produced normal numbers of virions, these particles were 8- to 10-fold less infectious than those produced in the presence of Ubc9. The nature of this defect was assayed for dependence on Ubc9 during viral assembly, …

Expression Of Hpv16 E5 Produces Enlarged Nuclei And Polyploidy Through Endoreplication, Lulin Hu, Tamara A. Potapova, Shibo Li, Susannah Rankin, Gary J. Gorbsky, Peter C. Angeletti, Brian P. Ceresa

Nebraska Center for Virology: Faculty Publications

Anogenital cancers and head and neck cancers are causally-associated with infection by high-risk

human papillomavirus (HPV). The mechanism by which high-risk HPVs contribute to

oncogenesis is poorly understood. HPV16 encodes three genes (HPV16 E5, E6, and E7) that can

transform cells when expressed independently. HPV16 E6 and E7 have well-described roles

causing genomic instability and unregulated cell cycle progression. The role of HPV16 E5 in cell

transformation remains to be elucidated. Expression of HPV16 E5 results in enlarged, polyploid

nuclei that are dependent on the level and duration of HPV16 E5 expression. Live-cell imaging

data indicate these changes do not …

Human Papillomavirus 16 E5 Induces Bi-Nucleated Cell Formation By Cell-Cell Fusion, Lulin Ha, Kendra Plafker, Valeriya Vorozhoko, Rosemary E. Zuna, Marie H. Hanigan, Gary J. Gorbsky, Scott M. Plafker, Peter C. Angeletti, Brian P. Ceresa

Nebraska Center for Virology: Faculty Publications

Human Papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes – E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, …

A Comparative Study Of Hiv-1 Clade C Env Evolution In A Zambian Infant With An Infected Rhesus Macaque During Disease Progression, For Yue Tso, Federico G. Hoffmann, Damien C. Tully, Philippe Lemey, Robert A. Rasmussen, Hong Zhang, Ruth M. Ruprecht, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To evaluate whether HIV-1 clade C (HIV-C) envelope variations that arise during disease progression in rhesus macaque model reflect changes that occur naturally in human infection.

Design—An infant macaque was infected with SHIV-1157i, an R5 tropic clade C SHIV (SHIV-C) which expresses a primary HIV-C envelope derived from an infected human infant, and monitored over a five-year period. Genetic variation of the V1-V5 envelope region, which is the main target for humoral immune responses, derived from the infected macaque and infant was examined.

Methods—V1-V5 envelope region were cloned and sequenced from longitudinal PBMC samples collected from the infected macaque and …

Protection Against Mucosal Shiv Challenge By Peptide And Helper-Dependent Adenovirus Vaccines, Eric A. Weaver, Pramod N. Nehete, Bharti P. Nehete, Stephanie J. Buchl, Donna Palmer, David C. Montefiori, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env) peptides and first generation adenovirus serotype 5 (FG-Ad5) vaccines expressing the same peptides were immunized intramuscularly three times with helper- dependent adenovirus (HD-Ad) vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5- immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than …

Effects Of Shielding Adenoviral Vectors With Polyethylene Glycol On Vector-Specific And Vaccine-Mediated Immune Responses, Eric A. Weaver, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Many individuals have been previously exposed to human adenovirus serotype 5 (Ad5). This prior immunity has long been known to hinder its use for gene therapy and as a gene-based vaccine. Given these immunogenicity problems, we have tested whether polyethylene glycol (PEG) can blunt immune effects against Ad5 during systemic and mucosal vaccination. Ad5 vectors were covalently modified with 5-, 20-, and 35-kDa linear PEG polymers and evaluated for their ability to produce immune responses against transgene antigen products and the vector itself. We show that shielding Ad5 with different-sized PEGs generally reduces transduction and primary antibody responses by the …

Mechanisms Of T Helper Cell Modulation In A Simulated Space Radiation Environment, Asma Rizvi

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure to solar particle events (SPEs) poses the most serious threat to astronaut health. Due to this radiation environment, exploration of the solar system beyond Earth’s orbit entails many risks for the crew on these deep space missions. Depression or dysfunction of the immune system is a major concern due to its high radio-sensitivity; potential consequences include overwhelming infection, development of cancer, fibrosis, and poor wound healing. Astronauts are also exposed to low dose/low dose rate (LDR) radiation. A three month stay at the international space station exposes them to ~ 0.05 Gy of radiation.

C57BL/6 mice received LDR gamma-radiation …

A Versatile Assay For The Identification Of Rna Silencing Suppressors Based On Complementation Of Viral Movement, Jason G. Powers, Tim L. Sit, Feng Qu, T. Jack Morris, Kook-Hyung Kim, Steven A. Lommel

Nebraska Center for Virology: Faculty Publications

The cell-to-cell movement of Turnip crinkle virus (TCV) in Nicotiana benthamiana requires the presence of its coat protein (CP), a known suppressor of RNA silencing. RNA transcripts of a TCV construct containing a reporter gene (green fluorescent protein) (TCV-sGFP) in place of the CP open reading frame generated foci of three to five cells. TCV CP delivered in trans by Agrobacterium tumefaciens infiltration potentiated movement of TCV-sGFP and increased foci diameter, on average, by a factor of four. Deletion of the TCV movement proteins in TCV-sGFP (construct TCVΔ92-sGFP) abolished the movement complementation ability of TCV CP. Other known suppressors of …

Development Of An Immunofluorescence Assay Using Recombinant Proteins Expressed In Insect Cells To Screen And Confirm Presence Of Human Herpesvirus 8-Specific Antibodies, Veenu Minhas, Lynsey N. Crosby, Kay L. Crabtree, Saul Phiri, Tendai J. M'Soka, Chipepo Kankasa, William J. Harrington, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 8 (HHV-8), or Kaposi’s sarcoma (KS)-associated herpesvirus, has been linked to all forms of KS. The results of most current serological assays for the detection of HHV-8-specific antibodies have low levels of concordance among themselves. To establish a sensitive and specific testing strategy that can be used to screen for HHV-8-specific antibodies, three HHV-8 proteins, ORF65, ORF73, and K8.1A, were expressed by using baculoviral vectors in insect cells and incorporated into a monoclonal antibodyenhanced immunofluorescence assay (mIFA) termed the Sf9 three-antigen mIFA. The results obtained by this mIFA were compared to those obtained by a standard mIFA with …

Small-Molecule Cd4 Mimics Interact With A Highly Conserved Pocket On Hiv-1 Gp120, Navid Madani, Arne Schön, Amy M. Princiotto, Judith M. Lalonde, Joel R. Cpurter, Takahiro Soeta, Danny Ng, Liping Wang, Evan T. Brower, Shi-Hua Xiang, Young Do Kwon, Chih-Chin Huang, Richard Wyatt, Peter D. Kwong, Ernesto Freire, Amos B. Smith Iii, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus (HIV-1) interaction with the primary receptor, CD4, induces conformational changes in the viral envelope glycoproteins that allow binding to the CCR5 second receptor and virus entry into the host cell. The small molecule NBD-556 mimics CD4 by binding the gp120 exterior envelope glycoprotein, moderately inhibiting virus entry into CD4-expressing target cells, and enhancing CCR5 binding and virus entry into CCR5-expressing cells lacking CD4. Studies of NBD-556 analogues and gp120 mutants suggest that: 1) NBD-556 binds within the Phe 43 cavity, a highly conserved, functionally important pocket formed as gp120 assumes the CD4- bound conformation; 2) the NBD-556 …

The Human Immunodeficiency Virus Type 1 Envelope Confers Higher Rates Of Replicative Fitness To Perinatally Transmitted Viruses Than To Nontransmitted Viruses, Xiaohong Kong, John T. West, Hong Zhang, Danielle M. Shea, Tendai J. M’Soka, Charles Wood

Nebraska Center for Virology: Faculty Publications

Selection of a minor viral genotype during perinatal transmission of human Immunodeficiency virus type 1

(HIV-1) has been observed, but there is a lack of information on the correlation of the restrictive transmission

with biological properties of the virus, such as replicative fitness. Recombinant viruses expressing the enhanced

green fluorescent protein or the Discosoma sp. red fluorescent (DsRed2) protein carrying the V1 to V5

regions of env from seven mother-infant pairs (MIPs) infected by subtype C HIV-1 were constructed, and

competition assays were carried out to compare the fitness between the transmitted and nontransmitted

viruses. Flow cytometry was used to …

Varying Efficiency Of Long-Term Replication Of Papillomaviruses In Saccharomyces Cerevisiae, Adam J. Rogers, Malte Loggen, Karen Lee, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Human papillomaviruses (HPVs) replicate in mitotically active basal keratinocytes. Two virally encoded proteins, E1, a helicase, and E2, a transcription factor, are important players in replication and maintenance of HPV episomes. We previously showed that HPV16 could replicate stably in Saccharomyces cerevisiae [Angeletti, P.C., Kim, K., Fernandes, F.J., and Lambert, P.F. (2002)] and we identified cis-elements that mediate replication and maintenance [J. Virol. 76(7), 3350-3358.; Kim, K., Angeletti, P.C., Hassebroek, E.C., and Lambert, P.F. (2005)]. Here, we demonstrate that although multiple HPV genomes replicate stably in yeast, they do so with differing long-term efficiency; HPV6-Ura3 is replicated at the …