Chronic wasting disease (CWD) is a fatal prion disease of North American deer and elk and poses an unclear risk for transmission to humans. Human exposure to CWD occurs through hunting activities and consumption of venison from prion-infected animals. Although the amino acid residues of the prion protein (PrP) that prevent or permit human CWD infection are unknown, NMR-based structural studies suggest that the β2-α2 loop (residues 165–175) may impact species barriers. Here we sought to define PrP sequence determinants that affect CWD transmission to humans. We engineered transgenic mice that express human PrP with four amino acid substitutions that result in expression of PrP with a β2-α2 loop (residues 165–175) that exactly matches that of elk PrP. Compared with transgenic mice expressing unaltered human PrP, mice expressing the human-elk chimeric PrP were highly susceptible to elk and deer CWD prions but were concurrently less susceptible to human Creutzfeldt-Jakob disease prions. A systematic in vitro survey of amino acid differences between humans and cervids identified two additional residues that impacted CWD conversion of human PrP. This work identifies amino acids that constitute a substantial structural barrier for CWD transmission to humans and helps illuminate the molecular requirements for cross-species prion transmission.
Timothy D. Kurt, Lin Jiang, Natalia Fernández-Borges, Cyrus Bett, Jun Liu, Tom Yang, Terry R. Spraker, Joaquín Castilla, David Eisenberg, Qingzhong Kong, Christina J. Sigurdson
While 30%–70% of RSV-infected infants develop bronchiolitis, 2% require hospitalization. It is not clear why disease severity differs among healthy, full-term infants; however, virus titers, inflammation, and Th2 bias are proposed explanations. While TLR4 is associated with these disease phenotypes, the role of this receptor in respiratory syncytial virus (RSV) pathogenesis is controversial. Here, we evaluated the interaction between TLR4 and environmental factors in RSV disease and defined the immune mediators associated with severe illness. Two independent populations of infants with RSV bronchiolitis revealed that the severity of RSV infection is determined by the
Mauricio T. Caballero, M. Elina Serra, Patricio L. Acosta, Jacqui Marzec, Luz Gibbons, Maximiliano Salim, Andrea Rodriguez, Andrea Reynaldi, Alejandro Garcia, Daniela Bado, Ursula J. Buchholz, Diego R. Hijano, Silvina Coviello, Dawn Newcomb, Miguel Bellabarba, Fausto M. Ferolla, Romina Libster, Ada Berenstein, Susana Siniawaski, Valeria Blumetti, Marcela Echavarria, Leonardo Pinto, Andrea Lawrence, M. Fabiana Ossorio, Arnoldo Grosman, Cecilia G. Mateu, Carola Bayle, Alejandra Dericco, Mariana Pellegrini, Ignacio Igarza, Horacio A. Repetto, Luciano Alva Grimaldi, Prathyusha Gudapati, Norberto R. Polack, Fernando Althabe, Min Shi, Fernando Ferrero, Eduardo Bergel, Renato T. Stein, R. Stokes Peebles, Mark Boothby, Steven R. Kleeberger, Fernando P. Polack
The phagocytosis of apoptotic cells and associated vesicles (efferocytosis) by DCs is an important mechanism for both self tolerance and host defense. Although some of the engulfment ligands involved in efferocytosis have been identified and studied in vitro, the contributions of these ligands in vivo remain ill defined. Here, we determined that during
Fanny Tzelepis, Mark Verway, Jamal Daoud, Joshua Gillard, Kimya Hassani-Ardakani, Jonathan Dunn, Jeffrey Downey, Marilena Elena Gentile, Joanna Jaworska, Anthony Michel Jean Sanchez, Yohann Nédélec, Hojatollah Vali, Maryam Tabrizian, Arnold Scott Kristof, Irah Luther King, Luis Bruno Barreiro, Maziar Divangahi
Ticks are notorious hematophagous ectoparasites and vectors of many deadly pathogens. As an effective vector, ticks must break the strong barrier provided by the skin of their host during feeding, and their saliva contains a complex mixture of bioactive molecules that paralyze host defenses. The receptor for advanced glycation end products (RAGE) mediates immune cell activation at inflammatory sites and is constitutively and highly expressed in skin. Here, we demonstrate that longistatin secreted with saliva of the tick
Anisuzzaman, Takeshi Hatta, Takeharu Miyoshi, Makoto Matsubayashi, M. Khyrul Islam, M. Abdul Alim, M. Abu Anas, M. Mehedi Hasan, Yasunobu Matsumoto, Yasuhiko Yamamoto, Hiroshi Yamamoto, Kozo Fujisaki, Naotoshi Tsuji
Many pathogens, including viruses, bacteria, and protozoan parasites, suppress cellular immune responses through activation of type I IFN signaling. Recent evidence suggests that immune suppression and susceptibility to the malaria parasite,
Ashraful Haque, Shannon E. Best, Marcela Montes de Oca, Kylie R. James, Anne Ammerdorffer, Chelsea L. Edwards, Fabian de Labastida Rivera, Fiona H. Amante, Patrick T. Bunn, Meru Sheel, Ismail Sebina, Motoko Koyama, Antiopi Varelias, Paul J. Hertzog, Ulrich Kalinke, Sin Yee Gun, Laurent Rénia, Christiane Ruedl, Kelli P.A. MacDonald, Geoffrey R. Hill, Christian R. Engwerda
Lyme disease, caused by the spirochete
Kenneth K.C. Bramwell, Ying Ma, John H. Weis, Xinjian Chen, James F. Zachary, Cory Teuscher, Janis J. Weis
Michail S. Lionakis, Muthulekha Swamydas, Brett G. Fischer, Theo S. Plantinga, Melissa D. Johnson, Martin Jaeger, Nathaniel M. Green, Andrius Masedunskas, Roberto Weigert, Constantinos Mikelis, Wuzhou Wan, Chyi-Chia Richard Lee, Jean K. Lim, Aymeric Rivollier, John C. Yang, Greg M. Laird, Robert T. Wheeler, Barbara D. Alexander, John R. Perfect, Ji-Liang Gao, Bart-Jan Kullberg, Mihai G. Netea, Philip M. Murphy
Rotavirus-induced diarrhea is a life-threatening disease in immunocompromised individuals and in children in developing countries. We have developed a system for prophylaxis and therapy against rotavirus disease using transgenic rice expressing the neutralizing variable domain of a rotavirus-specific llama heavy-chain antibody fragment (MucoRice-ARP1). MucoRice-ARP1 was produced at high levels in rice seeds using an overexpression system and RNAi technology to suppress the production of major rice endogenous storage proteins. Orally administered MucoRice-ARP1 markedly decreased the viral load in immunocompetent and immunodeficient mice. The antibody retained in vitro neutralizing activity after long-term storage (>1 yr) and boiling and conferred protection in mice even after heat treatment at 94°C for 30 minutes. High-yield, water-soluble, and purification-free MucoRice-ARP1 thus forms the basis for orally administered prophylaxis and therapy against rotavirus infections.
Daisuke Tokuhara, Beatriz Álvarez, Mio Mejima, Tomoko Hiroiwa, Yuko Takahashi, Shiho Kurokawa, Masaharu Kuroda, Masaaki Oyama, Hiroko Kozuka-Hata, Tomonori Nochi, Hiroshi Sagara, Farah Aladin, Harold Marcotte, Leon G.J. Frenken, Miren Iturriza-Gómara, Hiroshi Kiyono, Lennart Hammarström, Yoshikazu Yuki
Vaccine development for the blood stages of malaria has focused on the induction of antibodies to parasite surface antigens, most of which are highly polymorphic. An alternate strategy has evolved from observations that low-density infections can induce antibody-independent immunity to different strains. To test this strategy, we treated parasitized red blood cells from the rodent parasite
Michael F. Good, Jennifer M. Reiman, I. Bibiana Rodriguez, Koichi Ito, Stephanie K. Yanow, Ibrahim M. El-Deeb, Michael R. Batzloff, Danielle I. Stanisic, Christian Engwerda, Terry Spithill, Stephen L. Hoffman, Moses Lee, Virginia McPhun
Influenza A viruses cause significant morbidity and mortality worldwide. There is a need for alternative or adjunct therapies, as resistance to currently used antiviral drugs is emerging rapidly. We tested ligand epitope antigen presentation system (LEAPS) technology as a new immune-based treatment for influenza virus infection in a mouse model. Influenza-J-LEAPS peptides were synthesized by conjugating the binding ligand derived from the β2-microglobulin chain of the human MHC class I molecule (J-LEAPS) with 15 to 30 amino acid–long peptides derived from influenza virus NP, M, or HA proteins. DCs were stimulated with influenza-J-LEAPS peptides (influenza-J-LEAPS) and injected intravenously into infected mice. Antigen-specific LEAPS-stimulated DCs were effective in reducing influenza virus replication in the lungs and enhancing survival of infected animals. Additionally, they augmented influenza-specific T cell responses in the lungs and reduced the severity of disease by limiting excessive cytokine responses, which are known to contribute to morbidity and mortality following influenza virus infection. Our data demonstrate that influenza-J-LEAPS–pulsed DCs reduce virus replication in the lungs, enhance survival, and modulate the protective immune responses that eliminate the virus while preventing excessive cytokines that could injure the host. This approach shows promise as an adjunct to antiviral treatment of influenza virus infections.
Kobporn Boonnak, Leatrice Vogel, Marlene Orandle, Daniel Zimmerman, Eyal Talor, Kanta Subbarao
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