1
|
Weaver GC, Arya R, Schneider CL, Hudson AW, Stern LJ. Corrigendum: Structural Models for Roseolovirus U20 And U21: Non-Classical MHC-I Like Proteins From HHV-6A, HHV-6B, and HHV-7. Front Immunol 2022; 13:936968. [PMID: 35677042 PMCID: PMC9169504 DOI: 10.3389/fimmu.2022.936968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 05/09/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Grant C Weaver
- Immunology and Microbiology Graduate Program, Morningside Graduate School of Biomedical Sciences, UMass Chan Medical School, Worcester, MA, United States.,Department of Pathology, UMass Chan Medical School, Worcester, MA, United States
| | - Richa Arya
- Department of Pathology, UMass Chan Medical School, Worcester, MA, United States
| | | | - Amy W Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Lawrence J Stern
- Immunology and Microbiology Graduate Program, Morningside Graduate School of Biomedical Sciences, UMass Chan Medical School, Worcester, MA, United States.,Department of Pathology, UMass Chan Medical School, Worcester, MA, United States.,Department of Biochemistry and Molecular Biotechnology, UMass Chan Medical School, Worcester, MA, United States
| |
Collapse
|
2
|
Weaver GC, Arya R, Schneider CL, Hudson AW, Stern LJ. Structural Models for Roseolovirus U20 And U21: Non-Classical MHC-I Like Proteins From HHV-6A, HHV-6B, and HHV-7. Front Immunol 2022; 13:864898. [PMID: 35444636 PMCID: PMC9013968 DOI: 10.3389/fimmu.2022.864898] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 03/08/2022] [Indexed: 01/08/2023] Open
Abstract
Human roseolovirus U20 and U21 are type I membrane glycoproteins that have been implicated in immune evasion by interfering with recognition of classical and non-classical MHC proteins. U20 and U21 are predicted to be type I glycoproteins with extracytosolic immunoglobulin-like domains, but detailed structural information is lacking. AlphaFold and RoseTTAfold are next generation machine-learning-based prediction engines that recently have revolutionized the field of computational three-dimensional protein structure prediction. Here, we review the structural biology of viral immunoevasins and the current status of computational structure prediction algorithms. We use these computational tools to generate structural models for U20 and U21 proteins, which are predicted to adopt MHC-Ia-like folds with closed MHC platforms and immunoglobulin-like domains. We evaluate these structural models and place them within current understanding of the structural basis for viral immune evasion of T cell and natural killer cell recognition.
Collapse
Affiliation(s)
- Grant C. Weaver
- Immunology and Microbiology Graduate Program, Morningside Graduate School of Biomedical Sciences, UMass Chan Medical School, Worcester, MA, United States
- Department of Pathology, UMass Chan Medical School, Worcester, MA, United States
| | - Richa Arya
- Department of Pathology, UMass Chan Medical School, Worcester, MA, United States
| | | | - Amy W. Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Lawrence J. Stern
- Immunology and Microbiology Graduate Program, Morningside Graduate School of Biomedical Sciences, UMass Chan Medical School, Worcester, MA, United States
- Department of Pathology, UMass Chan Medical School, Worcester, MA, United States
- Department of Biochemistry and Molecular Biotechnology, UMass Chan Medical School, Worcester, MA, United States
| |
Collapse
|
3
|
Gibb B, Hyman P, Schneider CL. The Many Applications of Engineered Bacteriophages-An Overview. Pharmaceuticals (Basel) 2021; 14:ph14070634. [PMID: 34208847 PMCID: PMC8308837 DOI: 10.3390/ph14070634] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 06/26/2021] [Accepted: 06/26/2021] [Indexed: 12/18/2022] Open
Abstract
Since their independent discovery by Frederick Twort in 1915 and Felix d’Herelle in 1917, bacteriophages have captured the attention of scientists for more than a century. They are the most abundant organisms on the planet, often outnumbering their bacterial hosts by tenfold in a given environment, and they constitute a vast reservoir of unexplored genetic information. The increased prevalence of antibiotic resistant pathogens has renewed interest in the use of naturally obtained phages to combat bacterial infections, aka phage therapy. The development of tools to modify phages, genetically or chemically, combined with their structural flexibility, cargo capacity, ease of propagation, and overall safety in humans has opened the door to a myriad of applications. This review article will introduce readers to many of the varied and ingenious ways in which researchers are modifying phages to move them well beyond their innate ability to target and kill bacteria.
Collapse
Affiliation(s)
- Bryan Gibb
- Department of Biological and Chemical Sciences, Theobald Science Center, Room 423, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
- Correspondence: (B.G.); (C.L.S.)
| | - Paul Hyman
- Department of Biology and Toxicology, Ashland University, 401 College Ave., Ashland, OH 44805, USA;
| | - Christine L. Schneider
- Department of Life Sciences, Carroll University, 100 North East Ave., Waukesha, WI 53186, USA
- Correspondence: (B.G.); (C.L.S.)
| |
Collapse
|
4
|
Zumwalde NA, Sharma A, Xu X, Ma S, Schneider CL, Romero-Masters JC, Hudson AW, Gendron-Fitzpatrick A, Kenney SC, Gumperz JE. Adoptively transferred Vγ9Vδ2 T cells show potent antitumor effects in a preclinical B cell lymphomagenesis model. JCI Insight 2017; 2:93179. [PMID: 28679955 DOI: 10.1172/jci.insight.93179] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/31/2017] [Indexed: 01/09/2023] Open
Abstract
A central issue for adoptive cellular immunotherapy is overcoming immunosuppressive signals to achieve tumor clearance. While γδ T cells are known to be potent cytolytic effectors that can kill a variety of cancers, it is not clear whether they are inhibited by suppressive ligands expressed in tumor microenvironments. Here, we have used a powerful preclinical model where EBV infection drives the de novo generation of human B cell lymphomas in vivo, and autologous T lymphocytes are held in check by PD-1/CTLA-4-mediated inhibition. We show that a single dose of adoptively transferred Vδ2+ T cells has potent antitumor effects, even in the absence of checkpoint blockade or activating compounds. Vδ2+ T cell immunotherapy given within the first 5 days of EBV infection almost completely prevented the outgrowth of tumors. Vδ2+ T cell immunotherapy given more than 3 weeks after infection (after neoplastic transformation is evident) resulted in a dramatic reduction in tumor burden. The immunotherapeutic Vδ2+ T cells maintained low cell surface expression of PD-1 in vivo, and their recruitment to tumors was followed by a decrease in B cells expressing PD-L1 and PD-L2 inhibitory ligands. These results suggest that adoptively transferred PD-1lo Vδ2+ T cells circumvent the tumor checkpoint environment in vivo.
Collapse
Affiliation(s)
| | | | - Xuequn Xu
- Department of Medical Microbiology and Immunology
| | - Shidong Ma
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Christine L Schneider
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - James C Romero-Masters
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Amy W Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Annette Gendron-Fitzpatrick
- Comparative Pathology Laboratory, Research Animal Resources Center, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Shannon C Kenney
- Department of Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | | |
Collapse
|
5
|
Sturgill ER, Malouli D, Hansen SG, Burwitz BJ, Seo S, Schneider CL, Womack JL, Verweij MC, Ventura AB, Bhusari A, Jeffries KM, Legasse AW, Axthelm MK, Hudson AW, Sacha JB, Picker LJ, Früh K. Natural Killer Cell Evasion Is Essential for Infection by Rhesus Cytomegalovirus. PLoS Pathog 2016; 12:e1005868. [PMID: 27580123 PMCID: PMC5006984 DOI: 10.1371/journal.ppat.1005868] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 08/12/2016] [Indexed: 02/06/2023] Open
Abstract
The natural killer cell receptor NKG2D activates NK cells by engaging one of several ligands (NKG2DLs) belonging to either the MIC or ULBP families. Human cytomegalovirus (HCMV) UL16 and UL142 counteract this activation by retaining NKG2DLs and US18 and US20 act via lysomal degradation but the importance of NK cell evasion for infection is unknown. Since NKG2DLs are highly conserved in rhesus macaques, we characterized how NKG2DL interception by rhesus cytomegalovirus (RhCMV) impacts infection in vivo. Interestingly, RhCMV lacks homologs of UL16 and UL142 but instead employs Rh159, the homolog of UL148, to prevent NKG2DL surface expression. Rh159 resides in the endoplasmic reticulum and retains several NKG2DLs whereas UL148 does not interfere with NKG2DL expression. Deletion of Rh159 releases human and rhesus MIC proteins, but not ULBPs, from retention while increasing NK cell stimulation by infected cells. Importantly, RhCMV lacking Rh159 cannot infect CMV-naïve animals unless CD8+ cells, including NK cells, are depleted. However, infection can be rescued by replacing Rh159 with HCMV UL16 suggesting that Rh159 and UL16 perform similar functions in vivo. We therefore conclude that cytomegaloviral interference with NK cell activation is essential to establish but not to maintain chronic infection. Natural killer (NK) cells are an important subset of the innate immune system that rapidly responds to cellular transformation and infection. The importance of NK cell control of viral infection is dramatically illustrated by our results revealing that cytomegalovirus (CMV) is unable to establish infections in healthy individuals unless NK cell responses are subverted. By studying infection of rhesus macaques with rhesus CMV, a highly representative animal model for human CMV, we identified a key viral factor that allows RhCMV to limit NK cell activation by preventing NK cell activating ligands from trafficking to the cell surface. Importantly, we observed that this avoidance of NK cell activation is essential to establish infection in vivo because RhCMV lacking the NK cell evasion factor was unable to infect animals unless NK cells were depleted. By unmasking such viral stealth strategies it might be possible to harness innate immunity to prevent viral infection, the primary goal of CMV vaccine development.
Collapse
Affiliation(s)
- Elizabeth R. Sturgill
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Daniel Malouli
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Scott G. Hansen
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Benjamin J. Burwitz
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Seongkyung Seo
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Christine L. Schneider
- Department of Life Sciences, Carroll University, Waukesha, Wisconsin, United States of America
| | - Jennie L. Womack
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Marieke C. Verweij
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Abigail B. Ventura
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Amruta Bhusari
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Krystal M. Jeffries
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Alfred W. Legasse
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Michael K. Axthelm
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Amy W. Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Jonah B. Sacha
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Louis J. Picker
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
- * E-mail:
| |
Collapse
|
6
|
Mellergaard M, Skovbakke SL, Schneider CL, Lauridsen F, Andresen L, Jensen H, Skov S. N-glycosylation of asparagine 8 regulates surface expression of major histocompatibility complex class I chain-related protein A (MICA) alleles dependent on threonine 24. J Biol Chem 2014; 289:20078-91. [PMID: 24872415 DOI: 10.1074/jbc.m114.573238] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
NKG2D is an activating receptor expressed on several types of human lymphocytes. NKG2D ligands can be induced upon cell stress and are frequently targeted post-translationally in infected or transformed cells to avoid immune recognition. Virus infection and inflammation alter protein N-glycosylation, and we have previously shown that changes in cellular N-glycosylation are involved in regulation of NKG2D ligand surface expression. The specific mode of regulation through N-glycosylation is, however, unknown. Here we investigated whether direct N-glycosylation of the NKG2D ligand MICA itself is critical for cell surface expression and sought to identify the essential residues. We found that a single N-glycosylation site (Asn(8)) was important for MICA018 surface expression. The frequently expressed MICA allele 008, with an altered transmembrane and intracellular domain, was not affected by mutation of this N-glycosylation site. Mutational analysis revealed that a single amino acid (Thr(24)) in the extracellular domain of MICA018 was essential for the N-glycosylation dependence, whereas the intracellular domain was not involved. The HHV7 immunoevasin, U21, was found to inhibit MICA018 surface expression by affecting N-glycosylation, and the retention was rescued by T24A substitution. Our study reveals N-glycosylation as an allele-specific regulatory mechanism important for regulation of surface expression of MICA018, and we pinpoint the residues essential for this N-glycosylation dependence. In addition, we show that this regulatory mechanism of MICA surface expression is likely targeted during different pathological conditions.
Collapse
Affiliation(s)
- Maiken Mellergaard
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| | - Sarah Line Skovbakke
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| | | | - Felicia Lauridsen
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| | - Lars Andresen
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| | - Helle Jensen
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| | - Søren Skov
- From the Laboratory of Immunology, Section for Experimental Animal Models, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870 Frederiksberg, Denmark and
| |
Collapse
|
7
|
Lochmatter C, Schneider CL, Ingram K, Keiser J, Schifferli JA. Schistosoma mansoni tetraspanning orphan receptor (SmTOR): a new vaccine candidate against schistosomiasis. Clin Exp Immunol 2013; 170:342-57. [PMID: 23121675 DOI: 10.1111/j.1365-2249.2012.04667.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
One approach to fight against schistosomiasis is to develop an efficient vaccine. Schistosoma mansoni tetraspanning orphan receptor (SmTOR) might be a vaccine candidate, as it is a tegument membrane protein expressed most highly in cercariae. In this study we characterized the recombinant first extracellular domain of SmTOR (rSmTORed1) as having the expected property to bind C2 of complement similarly to a smaller peptide of the same domain, and to produce specific and high-titre antibodies in BALB/c mice immunized using complete Freund's adjuvant/incomplete Freund's adjuvant (CFA/IFA). Immunization was protective against parasite infection, as demonstrated by a significant decrease in worm burden in immunized BALB/c mice versus the control groups over two independent trials [64 and 45% reduction for mean adult worm burden in immunized versus phosphate-bufferd saline (PBS) injected mice]. Interestingly, infection by itself did not lead to the generation of anti-rSmTORed1 antibodies, corresponding to the low frequency of specific anti-rSmTORed1 antibodies detected in the sera of patients infected with S. mansoni (2/20; 10%). These data suggest that, as opposed to the natural infection during which SmTOR induces antibodies only rarely, immunization with its smaller first extracellular domain might be more efficient.
Collapse
Affiliation(s)
- C Lochmatter
- Immunonephrology Laboratory, Department of Biomedicine, University Hospital Basel, Basel, Switzerland.
| | | | | | | | | |
Collapse
|
8
|
Schneider CL, Hudson AW. The human herpesvirus-7 (HHV-7) U21 immunoevasin subverts NK-mediated cytoxicity through modulation of MICA and MICB. PLoS Pathog 2011; 7:e1002362. [PMID: 22102813 PMCID: PMC3213103 DOI: 10.1371/journal.ppat.1002362] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 09/22/2011] [Indexed: 12/12/2022] Open
Abstract
Herpesviruses have evolved numerous immune evasion strategies to facilitate establishment of lifelong persistent infections. Many herpesviruses encode gene products devoted to preventing viral antigen presentation as a means of escaping detection by cytotoxic T lymphocytes. The human herpesvirus-7 (HHV-7) U21 gene product, for example, is an immunoevasin that binds to class I major histocompatibility complex molecules and redirects them to the lysosomal compartment. Virus infection can also induce the upregulation of surface ligands that activate NK cells. Accordingly, the herpesviruses have evolved a diverse array of mechanisms to prevent NK cell engagement of NK-activating ligands on virus-infected cells. Here we demonstrate that the HHV-7 U21 gene product interferes with NK recognition. U21 can bind to the NK activating ligand ULBP1 and reroute it to the lysosomal compartment. In addition, U21 downregulates the surface expression of the NK activating ligands MICA and MICB, resulting in a reduction in NK-mediated cytotoxicity. These results suggest that this single viral protein may interfere both with CTL-mediated recognition through the downregulation of class I MHC molecules as well as NK-mediated recognition through downregulation of NK activating ligands. The long coevolution of herpesviruses with their hosts has resulted in the development of a diverse array of viral immune evasion strategies and host counter-strategies. The identification of viral proteins that impair the function of cellular immune-recognition receptors has proven fertile ground for the discovery of fundamental concepts in immunology and cell biology. While the cytomegaloviruses have demonstrated an extraordinary array of immunoevasive tactics, little is known about the immunoevasive strategies of the closely-related human herpesvirus-7 (HHV-7). We have previously demonstrated that the U21 gene product from HHV-7 likely interferes with viral antigen presentation to cytotoxic T cells by rerouting class I major histocompatibility molecules to lysosomes for degradation. In addition to the host's cytotoxic T cell response, virus infection also induces the expression of Natural-Killer (NK) activating ligands, alerting cytotoxic NK cells to identify and kill virus-infected cells. Here we describe a novel function for the same viral protein - U21 - in interfering with NK cell recognition. Our findings provide the first indication that HHV-7, too, may have found it necessary to strategize mechanisms of NK escape.
Collapse
Affiliation(s)
- Christine L. Schneider
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Amy W. Hudson
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
9
|
Glosson NL, Gonyo P, May NA, Schneider CL, Ristow LC, Wang Q, Hudson AW. Insight into the mechanism of human herpesvirus 7 U21-mediated diversion of class I MHC molecules to lysosomes. J Biol Chem 2010; 285:37016-29. [PMID: 20833720 PMCID: PMC2978630 DOI: 10.1074/jbc.m110.125849] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 08/11/2010] [Indexed: 01/11/2023] Open
Abstract
The U21 open reading frame from human herpesvirus-7 encodes a membrane protein that associates with and redirects class I MHC molecules to the lysosomal compartment. The mechanism by which U21 accomplishes this trafficking excursion is unknown. Here we have examined the contribution of localization, glycosylation, domain structure, and the absence of substrate class I MHC molecules on the ability of U21 to traffic to lysosomes. Our results suggest the existence of a cellular protein necessary for U21-mediated rerouting of class I MHC molecules.
Collapse
Affiliation(s)
- Nicole L. Glosson
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Patrick Gonyo
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Nathan A. May
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Christine L. Schneider
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Laura C. Ristow
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Qiuhong Wang
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Amy W. Hudson
- From the Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| |
Collapse
|
10
|
LaCount DJ, Hanson SF, Schneider CL, Friesen PD. Caspase inhibitor P35 and inhibitor of apoptosis Op-IAP block in vivo proteolytic activation of an effector caspase at different steps. J Biol Chem 2000; 275:15657-64. [PMID: 10747956 DOI: 10.1074/jbc.m000791200] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Signal-induced activation of caspases, the critical protease effectors of apoptosis, requires proteolytic processing of their inactive proenzymes. Consequently, regulation of procaspase processing is critical to apoptotic execution. We report here that baculovirus pancaspase inhibitor P35 and inhibitor of apoptosis Op-IAP prevent caspase activation in vivo, but at different steps. By monitoring proteolytic processing of endogenous Sf-caspase-1, an insect group II effector caspase, we show that Op-IAP blocked the first activation cleavage at TETD downward arrowG between the large and small caspase subunits. In contrast, P35 failed to affect this cleavage, but functioned downstream to block maturation cleavages (DXXD downward arrow(G/A)) of the large subunit. Substitution of P35's reactive site residues with TETDG failed to increase its effectiveness for blocking TETD downward arrowG processing of pro-Sf-caspase-1, despite wild-type function for suppressing apoptosis. These data are consistent with the involvement of a novel initiator caspase that is resistant to P35, but directly or indirectly inhibitable by Op-IAP. The conservation of TETD downward arrowG processing sites among insect effector caspases, including Drosophila drICE and DCP-1, suggests that in vivo activation of these group II caspases involves a P35-insensitive caspase and supports a model wherein apical and effector caspases function through a proteolytic cascade to execute apoptosis in insects.
Collapse
Affiliation(s)
- D J LaCount
- Department of Biochemistry and the Institute for Molecular Virology, College of Agricultural and Life Sciences and Graduate School, University of Wisconsin, Madison, Wisconsin 53706, USA
| | | | | | | |
Collapse
|
11
|
Schneider CL, Cowles RL, Stuefer-Powell CL, Carr TP. Dietary stearic acid reduces cholesterol absorption and increases endogenous cholesterol excretion in hamsters fed cereal-based diets. J Nutr 2000; 130:1232-8. [PMID: 10801924 DOI: 10.1093/jn/130.5.1232] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The observation that dietary stearic acid does not raise plasma cholesterol concentration is well documented, although the regulating mechanisms are not completely understood. Therefore, we examined the effect of dietary stearic acid on cholesterol absorption and sterol balance using male Syrian hamsters fed modified NIH-07 cereal-based diets selectively enriched in palmitic acid (16:0), stearic acid (18:0), trans fatty acid (18:1t), cis oleic acid (18:1c) or linoleic acid (18:2). All diets contained 17 g/100 g total fat and 0.05 g/100 g cholesterol; the five fat blends were enriched 30% with the fatty acid of interest above a constant fatty acid background. Cholesterol absorption efficiency was 50-55% in all treatment groups except for the 18:0 group, in which cholesterol absorption was significantly reduced to 21%. Plasma total cholesterol concentration was significantly lower in the 18:0 group compared to the 16:0 group. Fecal neutral steroid excretion was significantly greater in hamsters fed the high 18:0 diet compared to the other treatment groups. After accounting for unabsorbed dietary cholesterol, endogenous cholesterol excretion was about 100% higher in the 18:0 group. Consequently, the calculated rate of whole body cholesterol synthesis was significantly increased by dietary 18:0. Bile acid excretion accounted for only 12-20% of total sterol output by the hamsters in this study. Thus, the data suggest that reduced plasma cholesterol concentration in hamsters fed high 18:0 diets may be influenced by reduced cholesterol absorption and increased excretion of endogenous cholesterol.
Collapse
Affiliation(s)
- C L Schneider
- Department of Nutritional Science and Dietetics, University of Nebraska, Lincoln, NE 68583-0806, USA
| | | | | | | |
Collapse
|
12
|
Carr TP, Cai G, Lee JY, Schneider CL. Cholesteryl ester enrichment of plasma low-density lipoproteins in hamsters fed cereal-based diets containing cholesterol. Proc Soc Exp Biol Med 2000; 223:96-101. [PMID: 10632967 DOI: 10.1046/j.1525-1373.2000.22313.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Male Syrian hamsters were fed 0.02, 0.03, or 0.05% cholesterol to test the hypothesis that moderate cholesterol intake increases the cholesteryl ester content of the plasma low-density lipoproteins (LDL). Dietary cholesterol levels of 0.02%-0.05% were chosen to reflect typical human intakes of cholesterol. Hamsters were fed ad libitum a cereal-based diet (modified NIH-07 open formula) for 15 weeks. Increasing dietary cholesterol from 0.02% to 0.05% resulted in significantly increased plasma LDL and high-density lipoprotein cholesterol concentration, increased liver cholesterol concentration, and increased total aorta cholesterol content. The cholesteryl ester content of plasma LDL was determined as the molar ratio of cholesteryl ester to apolipoprotein B and to surface lipid (i.e., phospholipid + free cholesterol). Increasing dietary cholesterol from 0.02% to 0.05% resulted in significantly increased cholesteryl ester content of LDL particles. Furthermore, cholesteryl ester content of LDL was directly associated with increased total aorta cholesterol, whereas a linear relationship between plasma LDL cholesterol concentration and aorta cholesterol was not observed. Thus, the data suggest that LDL cholesteryl ester content may be an important atherogenic feature of plasma LDL.
Collapse
Affiliation(s)
- T P Carr
- Department of Nutritional Scinece, University of Nebraska, Lincoln, 68583, USA.
| | | | | | | |
Collapse
|
13
|
Fisher AJ, Cruz WD, Zoog SJ, Schneider CL, Friesen PD. Crystal structure of baculovirus P35: role of a novel reactive site loop in apoptotic caspase inhibition. EMBO J 1999; 18:2031-9. [PMID: 10205157 PMCID: PMC1171287 DOI: 10.1093/emboj/18.8.2031] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The aspartate-specific caspases are critical protease effectors of programmed cell death and consequently represent important targets for apoptotic intervention. Baculovirus P35 is a potent substrate inhibitor of metazoan caspases, a property that accounts for its unique effectiveness in preventing apoptosis in phylogenetically diverse organisms. Here we report the 2.2 A resolution crystal structure of P35, the first structure of a protein inhibitor of the death caspases. The P35 monomer possesses a solvent-exposed loop that projects from the protein's main beta-sheet core and positions the requisite aspartate cleavage site at the loop's apex. Distortion or destabilization of this reactive site loop by site-directed mutagenesis converted P35 to an efficient substrate which, unlike wild-type P35, failed to interact stably with the target caspase or block protease activity. Thus, cleavage alone is insufficient for caspase inhibition. These data are consistent with a new model wherein the P35 reactive site loop participates in a unique multi-step mechanism in which the spatial orientation of the loop with respect to the P35 core determines post-cleavage association and stoichiometric inhibition of target caspases.
Collapse
Affiliation(s)
- A J Fisher
- Department of Chemistry and Section of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA.
| | | | | | | | | |
Collapse
|
14
|
Staszewski S, Massari FE, Kober A, Göhler R, Durr S, Anderson KW, Schneider CL, Waterbury JA, Bakshi KK, Taylor VI. Combination therapy with zidovudine prevents selection of human immunodeficiency virus type 1 variants expressing high-level resistance to L-697,661, a nonnucleoside reverse transcriptase inhibitor. J Infect Dis 1995; 171:1159-65. [PMID: 7538547 DOI: 10.1093/infdis/171.5.1159] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
L-697,661 is a human immunodeficiency virus type 1 (HIV-1)-specific nonnucleoside reverse transcriptase (RT) inhibitor. Its tolerability and activity in combination with zidovudine were evaluated in a 48-week double-blind study. One hundred nineteen zidovudine-naive HIV-1-infected patients with CD4 cell counts of 200-500/mm3 received either combination therapy, L-697,661 alone, or zidovudine alone. Activity was assessed by CD4 cell count changes. Selection for L-697,661-resistant virus was monitored by susceptibility testing of RT expressed by circulating viral RNA. Therapy was generally well tolerated. All groups receiving zidovudine exhibited transient increases in CD4 cell counts, while the L-697,661 monotherapy group showed a significant decline and yielded RT > 100-fold resistant to L-697,661 and associated with substitutions at RT residue 181. The RT from patients receiving combination therapy was maximally 15-fold less susceptible to L-697,661. Hence, cotreatment with zidovudine prevents selection of HIV-1 variants that are highly resistant to L-697,661 in patients naive to both compounds.
Collapse
Affiliation(s)
- S Staszewski
- Merck Research Laboratories, West Point, Pennsylvania, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Byrnes VW, Emini EA, Schleif WA, Condra JH, Schneider CL, Long WJ, Wolfgang JA, Graham DJ, Gotlib L, Schlabach AJ. Susceptibilities of human immunodeficiency virus type 1 enzyme and viral variants expressing multiple resistance-engendering amino acid substitutions to reserve transcriptase inhibitors. Antimicrob Agents Chemother 1994; 38:1404-7. [PMID: 7522428 PMCID: PMC188219 DOI: 10.1128/aac.38.6.1404] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
To evaluate the potential that multiply resistant human immunodeficiency virus type 1 variants may arise during combination nucleoside and nonnucleoside reverse transcriptase inhibitor therapy, we constructed a series of mutant reverse transcriptase enzymes and viruses that coexpressed various combinations of resistance-associated amino acid substitutions. Substitutions at residues 100 (Leu-->Ile) and 181 (Tyr-->Cys), which mediate resistance to the nonnucleosides, suppressed resistance to 3'-azido-3'-deoxythymidine (AZT) when coexpressed with AZT-specific substitutions. However, a number of viral variants that exhibited significantly reduced susceptibilities to both classes of inhibitors were constructed.
Collapse
Affiliation(s)
- V W Byrnes
- Merck Research Laboratories, West Point, Pennsylvania 19486
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Schleif WA, Murthy KK, Sardana VV, Schneider CL, Byrnes VW, Cobb KE, Roth E, Wolfgang JA, Hoffman JM, Smith AM. Attempted prophylaxis of human immunodeficiency virus type 1 infection in chimpanzees with a nonnucleoside reverse transcriptase inhibitor. AIDS Res Hum Retroviruses 1994; 10:107-10. [PMID: 7514014 DOI: 10.1089/aid.1994.10.107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Affiliation(s)
- W A Schleif
- Merck Research Laboratories, West Point, Pennsylvania 19486
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Byrnes VW, Sardana VV, Schleif WA, Condra JH, Waterbury JA, Wolfgang JA, Long WJ, Schneider CL, Schlabach AJ, Wolanski BS. Comprehensive mutant enzyme and viral variant assessment of human immunodeficiency virus type 1 reverse transcriptase resistance to nonnucleoside inhibitors. Antimicrob Agents Chemother 1993; 37:1576-9. [PMID: 7692811 PMCID: PMC188022 DOI: 10.1128/aac.37.8.1576] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The nonnucleoside reverse transcriptase (RT) inhibitors comprise a class of structurally diverse compounds that are functionally related and specific for the human immunodeficiency virus type 1 RT. Viral variants resistant to these compounds arise readily in cell culture and in treated, infected human. Therefore, the eventual clinical usefulness of the nonnucleoside inhibitors will rely on a thorough understanding of the genetic and biochemical bases for resistance. A study was performed to assess the effects of substitutions at each RT amino acid residue that influences the enzyme's susceptibility to the various nonnucleoside compounds. Single substitutions were introduced into both purified enzyme and virus. The resulting patterns of resistance were markedly distinct for each of the tested inhibitors. For instance, a > 50-fold loss of enzyme susceptibility to BI-RG-587 was engendered by any of four individual substitutions, while the same level of relative resistance to the pyridinone derivatives was mediated only by substitution at residue 181. Similarly, substitution at residue 181. Similarly, substitution at residue 106 had a noted effect on virus resistance to BI-RG-587 but not to the pyridinones. The opposite effect was mediated by a substitution at residue 179. Such knowledge of nonucleoside inhibitor resistance profiles may help in understanding the basis for resistant virus selection during clinical studies of these compounds.
Collapse
Affiliation(s)
- V W Byrnes
- Merck Research Laboratories, West Point, Pennsylvania 19486
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
LaFemina RL, Schneider CL, Robbins HL, Callahan PL, LeGrow K, Roth E, Schleif WA, Emini EA. Requirement of active human immunodeficiency virus type 1 integrase enzyme for productive infection of human T-lymphoid cells. J Virol 1992; 66:7414-9. [PMID: 1433523 PMCID: PMC240448 DOI: 10.1128/jvi.66.12.7414-7419.1992] [Citation(s) in RCA: 230] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) integrase enzyme exhibits significant amino acid sequence conservation with integrase proteins of other retroviruses. We introduced specific amino acid substitutions at a number of the conserved residue positions of recombinant HIV-1 integrase. Some of these substitutions resulted in proteins which were not able to be purified in the same manner as the wild-type enzyme, and these were not studied further. The remaining mutant enzymes were assessed for their abilities to perform functions characteristic of the integrase protein. These included specific removal of the terminal dinucleotides from oligonucleotide substrates representative of the viral U5-long terminal repeat, nonspecific cleavage of oligonucleotide substrates, and mediation of the strand transfer (integration) reaction. Substitution at position 43, within the protein's zinc finger motif region, resulted in an enzyme with reduced specificity for cleavage of the terminal dinucleotide. In addition, a double substitution of aspartic acid and glutamine for valine and glutamic acid, respectively, at positions 151 and 152 within the D,D(35)E motif region rendered the integrase protein inactive for all of its functions. The introduction of this double substitution into an infectious HIV-1 provirus yielded a mutant virus that was incapable of productively infecting human T-lymphoid cells in culture.
Collapse
Affiliation(s)
- R L LaFemina
- Merck Research Laboratories, West Point, Pennsylvania 19486
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Baas LS, Schneider CL. Temporary epicardial electrodes. Dimens Crit Care Nurs 1986; 5:80-92. [PMID: 3633801 DOI: 10.1097/00003465-198603000-00006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
|
20
|
Schneider CL, Nordlund DJ. Prevalence of vitamin and mineral supplement use in the elderly. J Fam Pract 1983; 17:243-247. [PMID: 6875483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
This study examines the belief of many health professionals that the elderly are vulnerable to misconceptions of what constitutes good nutrition, especially as it relates to the use of vitamin and mineral supplements. A canvass of several census tracts in Toledo and several townships in Defiance County, Ohio, identified 309 individuals 60 years of age or older who agreed to participate in this study. Forty-nine percent of those interviewed used some vitamin or mineral supplement. Of these, 77 percent were taking a multiple vitamin. Women were more likely to use supplements than men (53 percent vs 38 percent), and supplement use increased across the three age categories: 60 to 69 years (42 percent), 70 to 79 years (48 percent), 80 years and older (60 percent). More than 85 percent of those using supplements spent less than 2 percent of their income on supplements. Health benefits were perceived by 94 percent of those using supplements.
Collapse
|
21
|
Schneider CL. Treatment of hemorrhagic diathesis after saline-solution-induced abortion. JAMA 1972; 220:1749-50. [PMID: 12306385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/22/2023]
|
22
|
|
23
|
Schneider CL. Incident-oblique and transmitted illumination for intravital cinemicrography. J Biol Photogr Assoc 1969; 37:34-40. [PMID: 4884089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
24
|
Schneider CL, Henry MM. Meconium embolism in vivo. Pulmonary and systemic microcirculation (as in maternal amniotic embolism). Am J Obstet Gynecol 1968; 101:909-14. [PMID: 5659950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
25
|
Meyers NL, Schneider CL. A triple axis servohydraulic stage for cinemicrography. J Biol Photogr Assoc 1968; 36:106-14. [PMID: 5671192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
26
|
Schneider CL. Erythrocyte hemolysis and fibrination-fibrinolysis during retained abruptio placentae with hypovolemia and transient anuria. Obstet Gynecol 1968; 31:491-504. [PMID: 5643128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|