Search

Your search keyword '"BROWN, WENDY C."' showing total 438 results
Start Over Author "BROWN, WENDY C."
438 results on '"BROWN, WENDY C."'

10. The Genome Sequence of Taurine Cattle: A Window to Ruminant Biology and Evolution

Author

Elsik, Christine G., Tellam, Ross L., Worley, Kim C., Gibbs, Richard A., Elsik, Christine G., Tellam, Ross L, Gibbs, Richard A., Muzny, Donna M., Weinstock, George M., Adelson, David L, Eichler, Evan E., Elnitski, Laura, Elsik, Christine G., Guigó, Roderic, Hamernik, Debora L., Kappes, Steve M., Lewin, Harris A, Lynn, David J., Nicholas, Frank W., Reymond, Alexandre, Rijnkels, Monique, Skow, Loren C., Tellam, Ross L, Worley, Kim C., Zdobnov, Evgeny M., Gibbs, Richard A., Kappes, Steve M., Schook, Lawrence, Skow, Loren C., Weinstock, George M., Womack, James, Alioto, Tyler, Antonarakis, Stylianos E., Astashyn, Alex, Chapple, Charles E., Chen, Hsiu-Chuan, Chrast, Jacqueline, Câmara, Francisco, Elsik, Christine G., Ermolaeva, Olga, Guigó, Roderic, Henrichsen, Charlotte N., Hlavina, Wratko, Kapustin, Yuri, Kiryutin, Boris, Kitts, Paul, Kokocinski, Felix, Landrum, Melissa, Maglott, Donna, Pruitt, Kim, Reymond, Alexandre, Sapojnikov, Victor, Searle, Stephen M., Solovyev, Victor, Souvorov, Alexandre, Ucla, Catherine, Weinstock, George M., Wyss, Carine, Alioto, Tyler, Antonarakis, Stylianos E., Chapple, Charles E., Chrast, Jacqueline, Câmara, Francisco, Guigó, Roderic, Henrichsen, Charlotte N., Reymond, Alexandre, Ucla, Catherine, Wyss, Carine, Anzola, Juan M., Gerlach, Daniel, Zdobnov, Evgeny M., Elhaik, Eran, Elsik, Christine G., Graur, Dan, Reese, Justin T., Adelson, David L., Edgar, Robert C., McEwan, John C., Payne, Gemma M., Raison, Joy M., Junier, Thomas, Kriventseva, Evgenia V., Zdobnov, Evgeny M., Chrast, Jacqueline, Eyras, Eduardo, Henrichsen, Charlotte N., Plass, Mireya, Reymond, Alexandre, Donthu, Ravikiran, Larkin, Denis M., Lewin, Harris A., Nicholas, Frank W., Elnitski, Laura, Larkin, Denis M., Lewin, Harris A., Reecy, James, Yang, Mary Q., Adelson, David L, Chen, Lin, Cheng, Ze, Chitko-McKown, Carol G., Eichler, Evan E., Elnitski, Laura, Elsik, Christine G., Liu, George E., Matukumalli, Lakshmi K., Song, Jiuzhou, Zhu, Bin, Elsik, Christine G., Lynn, David J., Reese, Justin T., Bradley, Daniel G., Brinkman, Fiona S.L, Lau, Lilian P.L., Lynn, David J., Whiteside, Matthew D., Tellam, Ross L, Walker, Angela, Wheeler, Thomas T., Casey, Theresa, German, Bruce J., Lemay, Danielle G., Lynn, David J., Maqbool, Nauman J., Molenaar, Adrian J., Rijnkels, Monique, Lewin, Harris A., Seo, Seongwon, Stothard, Paul, Baldwin, Cynthia L., Baxter, Rebecca, Brinkmeyer-Langford, Candice L., Brown, Wendy C., Childers, Christopher P., Connelley, Timothy, Ellis, Shirley A., Fritz, Krista, Glass, Elizabeth J., Herzig, Carolyn T.A., livanainen, Antti, Lahmers, Kevin K., Skow, Loren C., Bennett, Anna K., Childers, Christopher P., Dickens, Michael C., Elsik, Christine G., Gilbert, James G.R., Hagen, Darren E., Reese, Justin T., Salih, Hanni, Aerts, Jan, Caetano, Alexandre R., Dalrymple, Brian, Elsik, Christine G., Fernando Garcia, Jose, Gibbs, Richard A., Gill, Clare A., Hamernik, Debora L, Hiendleder, Stefan G., Memili, Erdogan, Nicholas, Frank W., Reecy, James, Rijnkels, Monique, Skow, Loren C., Spurlock, Diane, Stothard, Paul, Tellam, Ross L, Weinstock, George M., Williams, John L, Worley, Kim C., Alexander, Lee, Brownstein, Michael J., Guan, Leluo, Holt, Robert A., Jones, Steven J.M., Marra, Marco A., Moore, Richard, Moore, Stephen S., Roberts, Andy, Taniguchi, Masaaki, Waterman, Richard C., Chacko, Joseph, Chandrabose, Mimi M., Cree, Andy, Diep Dao, Marvin, Dinh, Huyen H., Ayiesha Gabisi, Ramatu, Hines, Sandra, Hume, Jennifer, Jhangiani, Shalini N., Joshi, Vandita, Kovar, Christie L., Lewis, Lora R., Liu, Yih-shin, Lopez, John, Morgan, Margaret B., Muzny, Donna M., Bich Nguyen, Ngoc, Okwuonu, Geoffrey O., Ruiz, San Juana, Santibanez, Jireh, Wright, Rita A., Buhay, Christian, Ding, Yan, Dugan-Rocha, Shannon, Herdandez, Judith, Holder, Michael, Sabo, Aniko, Egan, Amy, Goodell, Jason, Wilczek-Boney, Katarzyna, Fowler, Gerald R., Edward Hitchens, Matthew, Lozado, Ryan J., Moen, Charles, Steffen, David, Warren, James T., Zhang, Jingkun, Chiu, Readman, Jones, Steven J.M., Marra, Marco A., Schein, Jacqueline E., James Durbin, K., Havlak, Paul, Jiang, Huaiyang, Liu, Yue, Qin, Xiang, Ren, Yanru, Shen, Yufeng, Song, Henry, Weinstock, George M., Worley, Kim C., Nicole Bell, Stephanie, Davis, Clay, Jolivet Johnson, Angela, Lee, Sandra, Nazareth, Lynne V., Patel, Bella Mayurkumar, Pu, Ling-Ling, Vattathil, Selina, Williams, Rex Lee, Jr., Curry, Stacey, Hamilton, Cerissa, Sodergren, Erica, Nazareth, Lynne V., Wheeler, David A., Adelson, David L, Aerts, Jan, Barris, Wes, Bennett, Gary L, Dalrymple, Brian, Eggen, André, Gill, Clare A., Green, Ronnie D., Harhay, Gregory P., Hobbs, Matthew, Jann, Oliver, Kappes, Steve M., Keele, John W., Kent, Matthew P., Larkin, Denis M., Lewin, Harris A., Lien, Sigbjørn, McEwan, John C., McKay, Stephanie D., McWilliam, Sean, Moore, Stephen S., Nicholas, Frank W., Payne, Gemma M., Ratnakumar, Abhirami, Salih, Hanni, Schnabel, Robert D., Smith, Timothy, Snelling, Warren M., Sonstegard, Tad S., Stone, Roger T., Sugimoto, Yoshikazu, Takasuga, Akiko, Taylor, Jeremy F., Tellam, Ross L., Van Tassell, Curtis P., Williams, John L, MacNeil, Michael D., Abatepaulo, Antonio R.R., Abbey, Colette A., Aerts, Jan, Ahola, Virpi, Almeida, Iassudara G., Amadio, Ariel F., Anatriello, Elen, Bahadue, Suria M., Baldwin, Cynthia L., Baxter, Rebecca, Bennett, Anna K., Biase, Fernando H., Boldt, Clayton R., Brinkmeyer-Langford, Candice L, Brown, Wendy C., Caetano, Alexandre R., Carroll, Jeffery A., Carvalho, Wanessa A, Casey, Theresa, Cervelatti, Eliane P., Chacko, Elsa, Chapin, Jennifer E., Cheng, Ye, Childers, Christopher P., Choi, Jungwoo, Colley, Adam J., Connelley, Timothy, de Campos, Tatiana A., De Donato, Marcos, de Miranda Santos, Isabel K.F., de Oliveira, Carlo J.F., Deobald, Heather, Devinoy, Eve, Dickens, Michael C., Donohue, Kaitlin E., Dovc, Peter, Eberlein, Annett, Ellis, Shirley A., Fitzsimmons, Carolyn J., Franzin, Alessandra M., Fritz, Krista, Garcia, Gustavo R., Fernando Garcia, Jose, Genini, Sem, German, Bruce J., Gilbert, James G.R., Gill, Clare A., Gladney, Cody J., Glass, Elizabeth J., Grant, Jason R., Greaser, Marion L., Green, Jonathan A., Hadsell, Darryl L., Hagen, Darren E., Hakimov, Hatam A., Halgren, Rob, Harrow, Jennifer L, Hart, Elizabeth A., Hastings, Nicola, Hernandez, Marta, Herzig, Carolyn T.A., Hiendleder, Stefan G., Hobbs, Matthew, Hu, Zhi-Liang, livanainen, Antti, Ingham, Aaron, Iso-Touru, Terhi, Jamis, Catherine, Jann, Oliver, Jensen, Kirsty, Kapetis, Dimos, Kerr, Tovah, Khalil, Sari S., Khatib, Hasan, Kolbehdari, Davood, Kumar, Charu G., Kumar, Dinesh, Leach, Richard, Lee, Justin C-M, Lemay, Danielle G., Li, Changxi, Liu, George E., Logan, Krystin M., Malinverni, Roberto, Maqbool, Nauman J., Marques, Elisa, Martin, William F., Martins, Natalia F., Maruyama, Sandra R., Mazza, Raffaele, McLean, Kim L, Medrano, Juan F., Memili, Erdogan, Molenaar, Adrian J., Moreno, Barbara T., Moré, Daniela D., Muntean, Carl T., Nandakumar, Hari P., Nogueira, Marcelo F.G., Olsaker, Ingrid, Pant, Sameer D., Panzitta, Francesca, Pastor, Rosemeire C.P., Poli, Mario A., Poslusny, Nathan, Rachagani, Satyanarayana, Ranganathan, Shoba, Razpet, Andrej, Reecy, James, Riggs, Penny K., Rijnkels, Monique, Rincon, Gonzalo, Rodriguez-Osorio, Nelida, Rodriguez-Zas, Sandra L., Romero, Natasha E., Rosenwald, Anne, Sando, Lillian, Schmutz, Sheila M., Seo, Seongwon, Shen, Libing, Sherman, Laura, Skow, Loren C., Southey, Bruce R., Spurlock, Diane, Strandberg Lutzow, Ylva, Sweedler, Jonathan V., Tammen, Imke, Taniguchi, Masaaki, Tellam, Ross L, Telugu, Bhanu Prakash V.L, Urbanski, Jennifer M., Utsunomiya, Yuri T., Verschoor, Chris P., Waardenberg, Ashley J., Walker, Angela, Wang, Zhiquan, Ward, Robert, Weikard, Rosemarie, Welsh, Thomas H., Jr., Wheeler, Thomas T., White, Stephen N., Williams, John L, Wilming, Laurens G., Wunderlich, Kris R., Yang, Jianqi, and Zhao, Feng-Qi

Published
2009

14. Analysis of the Anaplasma marginale major surface protein 1 complex protein composition by tandem mass spectrometry

Author

Macmillan, Henriette, Brayton, Kelly A., Palmer, Guy H., McGuire, Travis C., Munske, Gerhard, Siems, William F., and Brown, Wendy C.

Subjects
Mass spectrometry -- Usage, Bacterial proteins -- Research, Liquid chromatography -- Usage, Biological sciences
Abstract

The protective major surface protein 1 (MSP1) complex of Anaplasma marginale is a heteromer of MSP1a and MSP1b, encoded by a multigene family. The mspl[beta] sequences were highly conserved throughout infection. However, liquid chromatography-tandem mass spectrometry analysis identified only a single MSPlb protein, MSP1b1, within the MSP1 complex.

Published
2006

28. Identification of a T-Cell Epitope That Is Globally Conserved among Outer Membrane Proteins (OMPs) OMP7, OMP8, and OMP9 of Anaplasma marginale Strains and with OMP7 from the A. marginale subsp. centrale Vaccine Strain

Author

Deringer, James R., primary, Forero-Becerra, Elkin G., additional, Ueti, Massaro W., additional, Turse, Joshua E., additional, Futse, James E., additional, Noh, Susan M., additional, Palmer, Guy H., additional, and Brown, Wendy C., additional

Published
2017
Full Text
View/download PDF

29. Immunogenicity of Outer Membrane Proteins VirB9-1 and VirB9-2, a Novel Nanovaccine against Anaplasma marginale

Author

Zhao, Liang, Mahony, Donna, Cavallaro, Antonino S., Zhang, Bing, Zhang, Jun, Deringer, James R., Zhao, Chun-Xia, Brown, Wendy C., Yu, Chengzhong, Mitter, Neena, Middelberg, Anton P. J., Zhao, Liang, Mahony, Donna, Cavallaro, Antonino S., Zhang, Bing, Zhang, Jun, Deringer, James R., Zhao, Chun-Xia, Brown, Wendy C., Yu, Chengzhong, Mitter, Neena, and Middelberg, Anton P. J.

Abstract

Anaplasma marginale is the most prevalent tick-borne livestock pathogen and poses a significant threat to cattle industry. In contrast to currently available live blood-derived vaccines against A. marginale, alternative safer and better-defined subunit vaccines will be of great significance. Two proteins (VirB9-1 and VirB9-2) from the Type IV secretion system of A. marginale have been shown to induce humoral and cellular immunity. In this study, Escherichia coli were used to express VirB9-1 and VirB9-2 proteins. Silica vesicles having a thin wall of 6 nm and pore size of 5.8 nm were used as the carrier and adjuvant to deliver these two antigens both as individual or mixed nano-formulations. High loading capacity was achieved for both proteins, and the mouse immunisation trial with individual as well as mixed nano-formulations showed high levels of antibody titres over 107 and strong T-cell responses. The mixed nano-formulation also stimulated high-level recall responses in bovine T-cell proliferation assays. These results open a promising path towards the development of efficient A. marginale vaccines and provide better understanding on the role of silica vesicles to deliver multivalent vaccines as mixed nano-formulations able to activate both B-cell and T-cell immunity, for improved animal health.

Published
2016

34. Loss of Immunization-Induced Epitope-Specific CD4 T-Cell Response following Anaplasma marginale Infection Requires Presence of the T-Cell Epitope on the Pathogen and Is Not Associated with an Increase in Lymphocytes Expressing Known Regulatory Cell Phenotypes

Author

Brown, Wendy C., primary, Turse, Joshua E., additional, Lawrence, Paulraj K., additional, Johnson, Wendell C., additional, Scoles, Glen A., additional, Deringer, James R., additional, Sutten, Eric L., additional, Han, Sushan, additional, and Norimine, Junzo, additional

Published
2015
Full Text
View/download PDF

36. Rapid deletion of antigen-specific CD4+ T cells following infection represents a strategy of immune evasion and persistence for Anaplasma marginale1

Author

Han, Sushan, Norimine, Junzo, Palmer, Guy H., Mwangi, Waithaka, Lahmers, Kevin K., and Brown, Wendy C.

Subjects
CD4-Positive T-Lymphocytes, Anaplasmosis, Antigens, Bacterial, Time Factors, Cattle Diseases, Clonal Deletion, Epitopes, T-Lymphocyte, Bacteremia, Article, Anaplasma marginale, Organ Specificity, Animals, Cattle, Immunologic Memory, Bacterial Outer Membrane Proteins
Abstract

Acquired T-cell immunity is central for protection against infection. However, the immunological consequences of exposing memory T cells to high antigen loads during acute and persistent infection with systemic pathogens are poorly understood. We investigated this using infection with Anaplasma marginale, a ruminant pathogen that replicates to levels of 109 bacteria per ml of blood during acute infection and maintains mean bacteremia levels of 106 per ml during long-term persistent infection. We established that immunization-induced antigen-specific peripheral blood CD4+ T cell responses were rapidly and permanently lost following infection. To determine whether these T cells were anergic, sequestered in the spleen, or physically deleted from peripheral blood, CD4+ T lymphocytes from the peripheral blood specific for major surface protein (MSP)1a T-cell epitope were enumerated by DRB3*1101 tetramer staining and FACS analysis throughout the course of immunization and challenge. Immunization induced significant epitope-specific T lymphocyte responses that rapidly declined near peak bacteremia to background levels. Concomitantly, the mean frequency of tetramer+ CD4+ cells decreased rapidly from 0.025% before challenge to a pre-immunization level of 0.0003% of CD4+ T cells. Low frequencies of tetramer+ CD4+ T cells in spleen, liver, and inguinal lymph nodes sampled 9-12 weeks post-challenge were consistent with undetectable or unsustainable antigen-specific responses and the lack of T-cell sequestration. Thus, infection of cattle with A. marginale leads to the rapid loss of antigen-specific T cells and immunologic memory, which may be a strategy for this pathogen to modulate the immune response and persist.

Published
2008

37. Advances in immunology and vaccine discovery. Report of the United States-European Commission Workshop

Author

Gay, Cyril G., Richie, Thomas L, Pastoret, Paul-Pierre, Minguez-Tudela, Isabel, De Baetselier, Patrick, Gobel, Thomas, Goddeeris, Bruno, Kaiser, Pete, Morrison, Ivan, Sanchez-Vizcaino, José Manuel, Anderson, Kevin, Baillie, Leslie W, Brown, Wendy C, Estes, D. Mark, Herrera, Eileen, Nara, Peter L, Ockenhouse, Chris F., Roth, James A, Sztein, Marcelo B, and Cellular and Molecular Immunology

Subjects
Innate immunity, immunogenetics, biodefense, Immune evasion, genomics, mucosal immunity, Vaccine, comparative immunology
Abstract

As the 21st century unfolds, infectious diseases remain one of the most significant threats to our economy, our food animal production systems, animal welfare, and most importantly, the lives of people worldwide, regardless of their economic standing. The potential use of biological threat agents for terrorism or biowarfare further undermines the security of our society. Arguably, vaccines represent the single most cost-effective, medically delivered strategy for confronting these challenges. The workshop "Advances in Immunology and Vaccine Discovery" was organized to address these challenges, based on the conviction that the interface between immunology and vaccinology offers the best prospects for major breakthroughs in vaccine discovery and development. Six focus areas were identified by workshop organizers: (1) pathogen immune evasion; (2) innate immunity; (3) mucosal immunity; (4) immunogenetics; (5) comparative immunology; and (6) genomics. These areas provided opportunities to elucidate how protective immunity may relate to the disruption of the molecular mechanisms that underlie host-pathogen interactions. A report generated by workshop organizers and participants provides key recommendations and identifies important research gaps, needs, future steps, and potential strategic US-EU collaborations. The report is available on line through ScienceDirect (URL).

Published
2007

38. Rapid and long-term disappearance of CD4+ T lymphocyte responses specific for Anaplasma marginale major surface protein-2 (MSP2) in MSP2 vaccinates following challenge with live A. marginale

Author

Abbott, Jeffrey R, Palmer, Guy H, Kegerreis, Kimberly A, Hetrick, Peter F, Howard, Chris J, Hope, Jayne, and Brown, Wendy C

Subjects
Vaccines, Attenuated/immunology, Molecular Sequence Data, Interferon-gamma/secretion, T-Lymphocytes, Regulatory/immunology, Anaplasma marginale/immunology, CD4-Positive T-Lymphocytes/cytology, Leukocytes, Mononuclear/microbiology, Antigen-Presenting Cells/microbiology, Rickettsia/immunology, parasitic diseases, Antigen-Presenting Cells/immunology, Antigens, Bacterial/immunology, Animals, Amino Acid Sequence, Lymphocyte Count, Leukocytes, Mononuclear/immunology, Cell Survival/immunology, Cell Proliferation, CD4-Positive T-Lymphocytes/metabolism, Enzyme-Linked Immunosorbent Assay/methods, Leukocytes, Mononuclear/secretion, Anaplasmosis/microbiology, CD4-Positive T-Lymphocytes/microbiology, Clostridium/immunology, Immunodominant Epitopes/immunology, Bacterial Vaccines/immunology, Coculture Techniques, Vaccines, Attenuated/administration & dosage, Growth Inhibitors/immunology, Bacterial Outer Membrane Proteins/administration & dosage, Bacterial Vaccines/administration & dosage, CD4-Positive T-Lymphocytes/immunology, Antigens, Bacterial/administration & dosage, Cattle, Immunodominant Epitopes/administration & dosage, Immunization, Secondary/methods, Anaplasmosis/immunology, Bacterial Outer Membrane Proteins/immunology, Immunoglobulin G/biosynthesis
Abstract

In humans and ruminants infected with Anaplasma, the major surface protein 2 (MSP2) is immunodominant. Numerous CD4(+) T cell epitopes in the hypervariable and conserved regions of MSP2 contribute to this immunodominance. Antigenic variation in MSP2 occurs throughout acute and persistent infection, and sequentially emerging variants are thought to be controlled by variant-specific Ab. This study tested the hypothesis that challenge of cattle with Anaplasma marginale expressing MSP2 variants to which the animals had been immunized, would stimulate variant epitope-specific recall CD4(+) T cell and IgG responses and organism clearance. MSP2-specific T lymphocyte responses, determined by IFN-gamma ELISPOT and proliferation assays, were strong before and for 3 wk postchallenge. Surprisingly, these responses became undetectable by the peak of rickettsemia, composed predominantly of organisms expressing the same MSP2 variants used for immunization. Immune responsiveness remained insignificant during subsequent persistent A. marginale infection up to 1 year. The suppressed response was specific for A. marginale, as responses to Clostridium vaccine Ag were consistently observed. CD4(+)CD25(+) T cells and cytokines IL-10 and TGF-beta1 did not increase after challenge. Furthermore, a suppressive effect of nonresponding cells was not observed. Lymphocyte proliferation and viability were lost in vitro in the presence of physiologically relevant numbers of A. marginale organisms. These results suggest that loss of memory T cell responses following A. marginale infection is due to a mechanism other than induction of T regulatory cells, such as peripheral deletion of MSP2-specific T cells.

Published
2005

39. Nanoparticle-Based Delivery of Anaplasma marginale Membrane Proteins; VirB9-1 and VirB10 Produced in the Pichia pastoris Expression System.

Author

Bing Zhang, Cavallaro, Antonio S., Mody, Karishma T., Jun Zhang, Deringer, James R., Brown, Wendy C., Mahony, Timothy J., Chengzhong Yu, and Mitter, Neena

Subjects
ANAPLASMOSIS, ANAPLASMA marginale, PICHIA pastoris, DIAGNOSIS
Abstract

Bovine anaplasmosis or cattle-tick fever is a tick-borne haemolytic disease caused by the rickettsial haemoparasite Anaplasma marginale in tropical and subtropical areas of the world. While difficult to express, the proteins VirB9-1 and VirB10 are immunogenic components of the outer membrane type IV secretion system that have been identified as candidate antigens for vaccines targeting of A. marginale. Soluble VirB9-1 and VirB10 were successfully expressed using Pichia pastoris. When formulated with the self-adjuvanting silica vesicles, SV-100 (diameter: 50 nm, and pore entrance size: 6 nm), 200 g of VirB9-1 and VirB10 were adsorbed per milligram of nanoparticle. The VirB9-1 and VirB10, SV-100 formulations were shown to induce higher antibody responses in mice compared to the QuilA formulations. Moreover, intracellular staining of selected cytokines demonstrated that both VirB9-1 and VirB10 formulations induced cell-mediated immune responses in mice. Importantly, the SV-100 VirB9-1 and VirB10 complexes were shown to specifically stimulate bovine T-cell linages derived from calves immunised with A. marginale outer membrane fractions, suggesting formulations will be useful for bovine immunisation and protection studies. Overall this study demonstrates the potential of self-adjuvanting silica vesicle formulations to address current deficiencies in vaccine delivery applications. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

40. Anaplasma marginale major surface protein 2 CD4+-T-cell epitopes are evenly distributed in conserved and hypervariable regions (HVR), whereas linear B-cell epitopes are predominantly located in the HVR

Author

Abbott, Jeffrey R, Palmer, Guy H, Howard, Chris J, Hope, Jayne, and Brown, Wendy C.

Subjects
Interferon-gamma/biosynthesis, Immunoglobulin G/blood, Antigens, Bacterial/immunology, CD4-Positive T-Lymphocytes/immunology, Animals, Epitopes, B-Lymphocyte, Epitopes, T-Lymphocyte, Antibodies, Bacterial/blood, Cattle, Bacterial Outer Membrane Proteins/immunology, Anaplasma marginale/immunology
Abstract

Organisms in the genus Anaplasma express an immunodominant major surface protein 2 (MSP2), composed of a central hypervariable region (HVR) flanked by highly conserved regions. Throughout Anaplasma marginale infection, recombination results in the sequential appearance of novel MSP2 variants and subsequent control of rickettsemia by the immune response, leading to persistent infection. To determine whether immune evasion and selection for variant organisms is associated with a predominant response against HVR epitopes, T-cell and linear B-cell epitopes were localized by measuring peripheral blood gamma interferon-secreting cells, proliferation, and antibody binding to 27 overlapping peptides spanning MSP2 in 16 cattle. Similar numbers of MSP2-specific CD4(+) T-cell epitopes eliciting responses of similar magnitude were found in conserved and hypervariable regions. T-cell epitope clusters recognized by the majority of animals were identified in the HVR (amino acids [aa] 171 to 229) and conserved regions (aa 101 to 170 and 272 to 361). In contrast, linear B-cell epitopes were concentrated in the HVR, residing within hydrophilic sequences. The pattern of recognition of epitope clusters by T cells and of HVR epitopes by B cells is consistent with the influence of protein structure on epitope recognition.

Published
2004

44. The Repertoire of Anaplasma marginale Antigens Recognized by CD4+ T-Lymphocyte Clones from Protectively Immunized Cattle Is Diverse and Includes Major Surface Protein 2 (MSP-2) and MSP-3

Author

Brown, Wendy C., Zhu, Daming, Shkap, Varda, McGuire, Travis C., Blouin, Edmour F., Kocan, Katherine M., and Palmer, Guy H.

Subjects
Male, Anaplasmosis, Antigens, Bacterial, Anaplasma, Ixodes, Vaccination, T-Lymphocytes, Helper-Inducer, Clone Cells, Bacterial Proteins, parasitic diseases, Microbial Immunity and Vaccines, Animals, Cytokines, Cattle, RNA, Messenger, Cell Division
Abstract

Major surface proteins of Anaplasma marginale are vaccine candidates. We recently demonstrated that immunization of calves with outer membranes of the Florida strain of A. marginale resulted in protective immunity that correlated with a memory CD4(+) T-lymphocyte response specific for major surface protein 1 (MSP-1), MSP-2, and MSP-3 (W. C. Brown, V. Shkap, D. Zhu, T. C. McGuire, W. Tuo, T. F. McElwain, and G. H. Palmer, Infect. Immun. 66:5406-5413, 1998). As immunogens, these proteins have been shown to induce complete or partial protection against homologous challenge. To further define the T helper (Th) cell response to these and other A. marginale antigens and to determine conservation of Th cell epitopes among genetically distinct A. marginale strains, Th cell clones obtained prior to challenge from three immunized calves were characterized for antigen-specific responses. Nine distinct antigenic profiles were defined by 11 Th cell clones derived by stimulation with the Florida strain. Several clones responded to MSP-2, MSP-3, or both. All of these MSP-2- or MSP-3-specific clones and the majority of other clones that did not respond to MSPs recognized all bovine blood-passaged strains of A. marginale. These results demonstrate conservation of certain Th cell epitopes between MSP-2 and MSP-3 and show that Th cell epitopes in MSP-2, MSP-3, and undefined antigens are conserved among strains of A. marginale. Of seven clones that responded to the blood-passaged Virginia strain, two did not recognize antigen prepared from this strain cultured in tick cells, suggesting differences in the antigenic composition between these stages. Analysis of the cytokines expressed by the Th cells revealed that all clones expressed gamma interferon and tumor necrosis factor alpha, and most coexpressed interleukin-4. Our results provide a rationale for identifying Th cell epitopes conserved among different strains of A. marginale for inclusion in a nucleic acid or recombinant protein vaccine.

Published
1998

49. CD205 antigen targeting combined with dendritic cell recruitment factors and antigen-linked CD40L activation primes and expands significant antigen-specific antibody and CD4+ T cell responses following DNA vaccination of outbred animals

Author

Njongmeta, Leo M., primary, Bray, Jocelyn, additional, Davies, Christopher J., additional, Davis, William C., additional, Howard, Chris J., additional, Hope, Jayne C., additional, Palmer, Guy H., additional, Brown, Wendy C., additional, and Mwangi, Waithaka, additional

Published
2012
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results