D H Walker

Summary

Affiliation: University of Texas Medical Branch
Country: USA

Publications

  1. pmc Compartmentalized, functional role of angiogenin during spotted fever group rickettsia-induced endothelial barrier dysfunction: evidence of possible mediation by host tRNA-derived small noncoding RNAs
    Bin Gong
    Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX, USA
    BMC Infect Dis 13:285. 2013
  2. pmc Pathogenesis of Lassa fever
    Nadezhda E Yun
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
    Viruses 4:2031-48. 2012
  3. ncbi request reprint Pathogenic mechanisms of diseases caused by Rickettsia
    David H Walker
    University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:1-11. 2003
  4. ncbi request reprint Establishment of a novel endothelial target mouse model of a typhus group rickettsiosis: evidence for critical roles for gamma interferon and CD8 T lymphocytes
    D H Walker
    Department of Pathology, University of Texas Medical Branch, Galveston, USA
    Lab Invest 80:1361-72. 2000
  5. ncbi request reprint Rickettsiae and rickettsial infections: the current state of knowledge
    David H Walker
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Clin Infect Dis 45:S39-44. 2007
  6. ncbi request reprint Principles of the malicious use of infectious agents to create terror: reasons for concern for organisms of the genus Rickettsia
    David H Walker
    University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:739-42. 2003
  7. pmc The realities of biodefense vaccines against Rickettsia
    David H Walker
    University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0609, USA
    Vaccine 27:D52-5. 2009
  8. doi request reprint Emerging and re-emerging tick-transmitted rickettsial and ehrlichial infections
    David H Walker
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Med Clin North Am 92:1345-61, x. 2008
  9. pmc Critical role of cytotoxic T lymphocytes in immune clearance of rickettsial infection
    D H Walker
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 69:1841-6. 2001
  10. ncbi request reprint Tick-transmitted infectious diseases in the United States
    D H Walker
    University of Texas Medical Branch, Center for Tropical Diseases, Pathology, Galveston 77555 0609, USA
    Annu Rev Public Health 19:237-69. 1998

Research Grants

  1. SPOTTED FEVER RICKETTSIAL ANTIGENS
    David H Walker; Fiscal Year: 2010
  2. EHRLICHIA CHAFFEENSIS SURFACE PROTEINS
    David Walker; Fiscal Year: 2004
  3. SPOTTED FEVER RICKETTSIAL ANTIGENS
    David Walker; Fiscal Year: 2003
  4. Gammacell-220 Excel Refurbished Research Irradiator
    David Walker; Fiscal Year: 2006
  5. Region VI Center for Biodefence and Emerging Infections
    David Walker; Fiscal Year: 2007
  6. Ehrlichia chaffeensis protective proteins
    David H Walker; Fiscal Year: 2010
  7. Ehrlichia chaffeensis protective proteins
    David Walker; Fiscal Year: 2009
  8. Vaccine for Epidemic Typhus
    David Walker; Fiscal Year: 2007
  9. Spotted Fever Rickettesial Antigens
    David Walker; Fiscal Year: 2007
  10. Ehrlichia chaffeensis protective proteins
    David Walker; Fiscal Year: 2007

Collaborators

Detail Information

Publications117 found, 100 shown here

  1. pmc Compartmentalized, functional role of angiogenin during spotted fever group rickettsia-induced endothelial barrier dysfunction: evidence of possible mediation by host tRNA-derived small noncoding RNAs
    Bin Gong
    Department of Pathology, University of Texas Medical Branch at Galveston, Galveston, TX, USA
    BMC Infect Dis 13:285. 2013
    ..All these observations raise an intriguing hypothesis about a novel cytoplasmic role of ANG, which is induced upon infection with Rickettsia and generates tRFs that may play roles in SFG rickettsioses...
  2. pmc Pathogenesis of Lassa fever
    Nadezhda E Yun
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
    Viruses 4:2031-48. 2012
    ..However, further investigations are required in order to design improved diagnostic tools, an effective vaccine, and therapeutic agents...
  3. ncbi request reprint Pathogenic mechanisms of diseases caused by Rickettsia
    David H Walker
    University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:1-11. 2003
    ..The host cell receptor for the Rickettsia ligand and the mechanism of rickettsial escape from the phagosome need to be elucidated...
  4. ncbi request reprint Establishment of a novel endothelial target mouse model of a typhus group rickettsiosis: evidence for critical roles for gamma interferon and CD8 T lymphocytes
    D H Walker
    Department of Pathology, University of Texas Medical Branch, Galveston, USA
    Lab Invest 80:1361-72. 2000
    ..This model offers excellent opportunities for study of attenuation and pathogenetic mechanisms of typhus rickettsiae, which are established biologic weapons of potential use in bioterrorism...
  5. ncbi request reprint Rickettsiae and rickettsial infections: the current state of knowledge
    David H Walker
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Clin Infect Dis 45:S39-44. 2007
    ..However, disseminated intravascular coagulation rarely occurs. Immunity is mediated by reactive cytokine-activated rickettsicidal nitrogen and oxygen species and by clearance of rickettsiae by cytotoxic CD8 T cells...
  6. ncbi request reprint Principles of the malicious use of infectious agents to create terror: reasons for concern for organisms of the genus Rickettsia
    David H Walker
    University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:739-42. 2003
  7. pmc The realities of biodefense vaccines against Rickettsia
    David H Walker
    University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0609, USA
    Vaccine 27:D52-5. 2009
    ..Prospects for rational development of a safe, effective live attenuated vaccine are excellent...
  8. doi request reprint Emerging and re-emerging tick-transmitted rickettsial and ehrlichial infections
    David H Walker
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Med Clin North Am 92:1345-61, x. 2008
    ..Globally, many of these bacteria have been named but the genetic differences among them are often small, and many of their clinical manifestations may not be distinguishable diagnostically...
  9. pmc Critical role of cytotoxic T lymphocytes in immune clearance of rickettsial infection
    D H Walker
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 69:1841-6. 2001
    ..CTLs appear to be crucial to recovery from rickettsial infection...
  10. ncbi request reprint Tick-transmitted infectious diseases in the United States
    D H Walker
    University of Texas Medical Branch, Center for Tropical Diseases, Pathology, Galveston 77555 0609, USA
    Annu Rev Public Health 19:237-69. 1998
    ..Polymerase chain reaction, still a research tool, promises the greatest sensitivity, specificity, and timeliness. Prevention by vaccines is not yet a reality, although OspA-based vaccines offer hope for the prevention of Lyme disease...
  11. ncbi request reprint Immunohistochemical diagnosis of typhus rickettsioses using an anti-lipopolysaccharide monoclonal antibody
    D H Walker
    Center for Tropical Diseases and Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    Mod Pathol 10:1038-42. 1997
    ....
  12. ncbi request reprint Progress in rickettsial genome analysis from pioneering of Rickettsia prowazekii to the recent Rickettsia typhi
    David H Walker
    Department of Pathology, University of Texas Medical Branch Galveston, TX 77555 0609, USA
    Ann N Y Acad Sci 1063:13-25. 2005
    ..Resequencing revealed that eight annotated pseudogenes of E strain are actually intact genes. Comparative genomics of virulent and avirulent strains of rickettsial species may reveal their virulence factors...
  13. ncbi request reprint Ricketts creates rickettsiology, the study of vector-borne obligately intracellular bacteria
    David H Walker
    World Health Organization Collaborating Center for Tropical Diseases, Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77666 0609, USA
    J Infect Dis 189:938-55. 2004
  14. ncbi request reprint Fatal cardiac failure in a 7-month-old child
    David H Walker
    Department of Pathology, Center for Tropical Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Pediatr Dev Pathol 6:582-4. 2003
  15. pmc Immunization with Ehrlichia P28 outer membrane proteins confers protection in a mouse model of ehrlichiosis
    Patricia A Crocquet-Valdes
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Clin Vaccine Immunol 18:2018-25. 2011
    ..Partial protection induced by immunization with P28-9, P28-12, and P28-19 against Ehrlichia was associated with the generation of Ehrlichia-specific cell-mediated and humoral immune responses...
  16. doi request reprint Emerging and re-emerging rickettsioses: endothelial cell infection and early disease events
    David H Walker
    Department of Pathology, University of Texas, Medical Branch, Galveston, Texas 77555 0609, USA
    Nat Rev Microbiol 6:375-86. 2008
    ....
  17. ncbi request reprint A conserved, transcriptionally active p28 multigene locus of Ehrlichia canis
    J W McBride
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Gene 254:245-52. 2000
    ..canis infected DH82 cells, indicating that the genes are transcribed as monocistronic messages...
  18. ncbi request reprint Rickettsial infection in murine models activates an early anti-rickettsial effect mediated by NK cells and associated with production of gamma interferon
    A N Billings
    Department of Pathology, The University of Texas Medical Branch, Galveston 77555-0609, USA
    Am J Trop Med Hyg 65:52-6. 2001
    ..Thus, it appears that NK cells contribute to the early anti-rickettsial immune response, likely via a mechanism involving gamma interferon...
  19. pmc Molecular cloning and characterization of the 120-kilodalton protein gene of Ehrlichia canis and application of the recombinant 120-kilodalton protein for serodiagnosis of canine ehrlichiosis
    X J Yu
    Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    J Clin Microbiol 38:369-74. 2000
    ..canis p120 reacted with convalescent sera from dogs with canine ehrlichiosis. These results indicate that the recombinant p120 is a potential antigen for the serodiagnosis of canine ehrlichiosis...
  20. ncbi request reprint Rickettsia felis: molecular characterization of a new member of the spotted fever group
    D H Bouyer
    Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston 77555 0609, USA
    Int J Syst Evol Microbiol 51:339-47. 2001
    ..felis as a member of the SFG. The organism is passed trans-stadially and transovarially, and infection in the cat flea has been observed in the midgut, tracheal matrix, muscle, hypodermis, ovaries and testes...
  21. ncbi request reprint Detection of a spotted fever group rickettsia in Amblyomma cajennense (Acari: Ixodidae) in south Texas
    A N Billings
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    J Med Entomol 35:474-8. 1998
    ..cajennense ticks in Texas and the United States. If this rickettsia is pathogenic, exposure to infected A. cajennense ticks may pose a previously unrecognized health risk to people who have been fed upon by these ticks...
  22. pmc Molecular cloning of the gene for a conserved major immunoreactive 28-kilodalton protein of Ehrlichia canis: a potential serodiagnostic antigen
    J W McBride
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Clin Diagn Lab Immunol 6:392-9. 1999
    ..In addition, reactivity of sera from clinical cases of canine ehrlichiosis with the recombinant P28 demonstrated that the recombinant protein may be a reliable serodiagnostic antigen...
  23. ncbi request reprint Characterization of the complete transcriptionally active ehrlichia chaffeensis 28 kDa outer membrane protein multigene family
    X Yu
    Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Gene 248:59-68. 2000
    ..chaffeensis also. The large repertoire of the p28 genes in a single ehrlichial organism and antigenic diversity of the P28 among the isolates of E. chaffeensis suggest that P28s may be involved in immune avoidance...
  24. ncbi request reprint Immunization with a portion of rickettsial outer membrane protein A stimulates protective immunity against spotted fever rickettsiosis
    P A Crocquet-Valdes
    Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0609, USA
    Vaccine 20:979-88. 2001
    ..Production of IFN-gamma by antigen-exposed T-lymphocytes of DNA vaccine recipients indicated that cellular immunity had been stimulated...
  25. ncbi request reprint Phylogenetic analysis of the rompB genes of Rickettsia felis and Rickettsia prowazekii European-human and North American flying-squirrel strains
    C G Moron
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    Am J Trop Med Hyg 62:598-603. 2000
    ..Analysis of the R. felis rompB gene sequence showed 10-13% divergence from SFG rickettsiae and 18% divergence from the TG rickettsiae. The rompB of all sequenced strains of R. prowazekii showed an overall similarity of 99.7-99.9%...
  26. pmc Genetic diversity of the 28-kilodalton outer membrane protein gene in human isolates of Ehrlichia chaffeensis
    X J Yu
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, The University of Texas Medical Branch at Galveston, Galveston, Texas 77555 0609, USA
    J Clin Microbiol 37:1137-43. 1999
    ..chaffeensis might evade the host immune defenses. Whether or not immunization with the p28 of one strain of E. chaffeensis would confer cross-protection against other strains needs to be investigated...
  27. pmc Immunodiagnosis of Ehrlichia canis infection with recombinant proteins
    J W McBride
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555, USA
    J Clin Microbiol 39:315-22. 2001
    ..The results of this study demonstrate that the rP43 and rP28 are sensitive and reliable serodiagnostic antigens for E. canis infections...
  28. ncbi request reprint Identification of protective components of two major outer membrane proteins of spotted fever group Rickettsiae
    C M Diaz-Montero
    Department of Pathology and World Health Organization Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston 77555 0609, USA
    Am J Trop Med Hyg 65:371-8. 2001
    ....
  29. ncbi request reprint Overproduction of TNF-alpha by CD8+ type 1 cells and down-regulation of IFN-gamma production by CD4+ Th1 cells contribute to toxic shock-like syndrome in an animal model of fatal monocytotropic ehrlichiosis
    Nahed Ismail
    Departments of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
    J Immunol 172:1786-800. 2004
    ..In conclusion, uncontrolled TNF-alpha production by CD8(+) T cells together with a weak CD4(+) Th1 cell response are associated with immunopathology and failure to clear IOE in the fatal model of HME...
  30. ncbi request reprint The rickettsial outer-membrane protein A and B genes of Rickettsia australis, the most divergent rickettsia of the spotted fever group
    J Stenos
    Department of Pathology, University of Texas Medical Branch at Galveston 77550, USA
    Int J Syst Evol Microbiol 50:1775-9. 2000
    ..R. australis rOmpB is more similar to rOmpB of other SFG rickettsiae than to that of typhus group rickettsiae...
  31. pmc Mechanisms of immunity to Ehrlichia muris: a model of monocytotropic ehrlichiosis
    Hui Min Feng
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555, USA
    Infect Immun 72:966-71. 2004
    ..Protective immunity against monocytotropic E. muris is mediated by a combination of CD8 and CD4 T lymphocytes, gamma interferon, tumor necrosis factor alpha, and antibodies...
  32. pmc Animal model of fatal human monocytotropic ehrlichiosis
    E A Sotomayor
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
    Am J Pathol 158:757-69. 2001
    ..This tropism for macrophages and the pathological lesions closely resemble those of human monocytotropic ehrlichiosis for which it is a promising model for investigation of immunity and pathogenesis...
  33. pmc Comparison of Ehrlichia chaffeensis recombinant proteins for serologic diagnosis of human monocytotropic ehrlichiosis
    X J Yu
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    J Clin Microbiol 37:2568-75. 1999
    ..None of the recombinant antigens yielded false-positive results. All the sera reactive with the recombinant 28- or the 106-kDa proteins also reacted with the recombinant 120-kDa protein...
  34. ncbi request reprint A preliminary investigation of Ehrlichia species in ticks, humans, dogs, and capybaras from Brazil
    Marcelo B Labruna
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 7755 0609, USA
    Vet Parasitol 143:189-95. 2007
    ..canis infecting dogs in the Amazon region of Brazil. Further studies are needed to evaluate the presence of other agents of human and animal ehrlichioses in Brazil...
  35. pmc Antigenic protein modifications in Ehrlichia
    S Thomas
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas, USA
    Parasite Immunol 31:296-303. 2009
    ..muris and IOE have the same antigenic proteins. Finally, studies on post-translational protein modifications using a novel technique, Eastern blotting, showed that E. muris proteins are more lipoylated and glycosylated than those of IOE...
  36. ncbi request reprint Identification of the target cells of Orientia tsutsugamushi in human cases of scrub typhus
    C G Moron
    Department of Pathology, University of Texas Medical Branch at Galveston, 301 University Blvd, Galveston, TX 77555, USA
    Mod Pathol 14:752-9. 2001
    ..Electron microscopy confirmed the location of rickettsiae in endothelium and cardiac myocytes...
  37. ncbi request reprint Sequence and characterization of an Ehrlichia chaffeensis gene encoding 314 amino acids highly homologous to the NAD A enzyme
    X J Yu
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    FEMS Microbiol Lett 154:53-8. 1997
    ..canis and E. muris have 89.2% and 93.2% homology, respectively, to the NAD A of E. chaffeensis. We propose that the nadA gene may be an excellent candidate for a genetic tool for the phylogenetic study of ehrlichiae...
  38. pmc Histologic, serologic, and molecular analysis of persistent ehrlichiosis in a murine model
    Juan P Olano
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Am J Pathol 165:997-1006. 2004
    ..In conclusion, we have provided for the first time a complete histopathological, serological, immunohistochemical, and quantitative analysis of an animal model for the study of persistent ehrlichial infection...
  39. pmc Expression analysis of the T-cell-targeting chemokines CXCL9 and CXCL10 in mice and humans with endothelial infections caused by rickettsiae of the spotted fever group
    Gustavo Valbuena
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555, USA
    Am J Pathol 163:1357-69. 2003
    ..Our results suggest that CXCL9 and CXCL10 may play a role early during the immune response against rickettsial infections...
  40. ncbi request reprint Human ehrlichioses
    Juan P Olano
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
    Med Clin North Am 86:375-92. 2002
    ....
  41. ncbi request reprint Phylogenetic relationships of Anaplasma marginale and 'Ehrlichia platys' to other Ehrlichia species determined by GroEL amino acid sequences
    X J Yu
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    Int J Syst Evol Microbiol 51:1143-6. 2001
    ..The first two groups were relatively closely related (17-20% divergence), while the third group was only distantly related to the first two groups (62-73% divergence)...
  42. pmc Differential interaction of dendritic cells with Rickettsia conorii: impact on host susceptibility to murine spotted fever rickettsiosis
    Rong Fang
    Center for Biodefense and Emerging Infectious Diseases, 301 University Blvd, Galveston, TX 77555 0609, USA
    Infect Immun 75:3112-23. 2007
    ..conorii-infected BMDCs in the presence of IL-2. These data suggest that rickettsiae can target DCs to stimulate a protective type 1 response in resistant hosts but suppressive adaptive immunity in susceptible hosts...
  43. pmc Enzyme-linked immunosorbent assay with conserved immunoreactive glycoproteins gp36 and gp19 has enhanced sensitivity and provides species-specific immunodiagnosis of Ehrlichia canis infection
    Ana Maria Cardenas
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Clin Vaccine Immunol 14:123-8. 2007
    ..canis infections, including species-specific identification and the lack of sensitivity associated with low antibody titers early in the acute phase of the infection...
  44. pmc The absence of Toll-like receptor 4 signaling in C3H/HeJ mice predisposes them to overwhelming rickettsial infection and decreased protective Th1 responses
    Jeffrey M Jordan
    Department of Pathology and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0609, USA
    Infect Immun 76:3717-24. 2008
    ..Together, these data demonstrate that, while rickettsiae do not contain endotoxic lipopolysaccharide, they nevertheless initiate TLR4-specific immune responses, and these responses are important in protection...
  45. ncbi request reprint Rickettsial phospholipase A2 as a pathogenic mechanism in a model of cell injury by typhus and spotted fever group rickettsiae
    D H Walker
    Department of Pathology, University of Texas Medical Branch, Galveston 77555-0609, USA
    Am J Trop Med Hyg 65:936-42. 2001
    ..Neither the inhibitor nor antivenom impaired rickettsial active transport of L-lysine. Thus, host cell injury was mediated by a rickettsial phospholipase A2-dependent mechanism...
  46. ncbi request reprint Cloning and sequencing of the gene for a 120-kDa immunodominant protein of Ehrlichia chaffeensis
    X J Yu
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    Gene 184:149-54. 1997
    ..Hydropathy analysis of the deduced amino-acid sequence demonstrated that the repeat domain contains highly hydrophilic segments. The 120-kDa protein should be evaluated for a role in stimulating protective immunity...
  47. pmc Protective heterologous immunity against fatal ehrlichiosis and lack of protection following homologous challenge
    Nagaraja R Thirumalapura
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Infect Immun 76:1920-30. 2008
    ....
  48. pmc Role of tumor necrosis factor alpha (TNF-alpha) and interleukin-10 in the pathogenesis of severe murine monocytotropic ehrlichiosis: increased resistance of TNF receptor p55- and p75-deficient mice to fatal ehrlichial infection
    Nahed Ismail
    Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0609, USA
    Infect Immun 74:1846-56. 2006
    ..Our data suggest that fatal ehrlichiosis could be a multistep process, where TNF-alpha is not solely responsible for mortality...
  49. pmc Persistent infection contributes to heterologous protective immunity against fatal ehrlichiosis
    Nagaraja R Thirumalapura
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 77:5682-9. 2009
    ..muris. The study indicated that persistent ehrlichial infection contributes to heterologous protection by stimulating the maintenance of memory T-cell responses...
  50. pmc Molecular characterization of a novel Rickettsia species from Ixodes scapularis in Texas
    A N Billings
    University of Texas Medical Branch, Galveston 77555 0609, USA
    Emerg Infect Dis 4:305-9. 1998
    ..australis for the 17 kDa gene, R. helvetica for gltA, and R. montana for rompA. The new organism, provisionally designated as genotype Cooleyi, is highly divergent in three conserved genes from recognized Rickettsia species...
  51. ncbi request reprint Monoclonal antibody-based immunohistochemical diagnosis of rickettsialpox: the macrophage is the principal target
    D H Walker
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609, USA
    Mod Pathol 12:529-33. 1999
    ....
  52. ncbi request reprint Balancing protective immunity and immunopathology: a unifying model of monocytotropic ehrlichiosis
    Nahed Ismail
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 1063:383-94. 2005
    ..In this study, we consider the roles of innate and adaptive immune responses in terms of protection from severe ehrlichiosis and their potential roles in immunopathology...
  53. ncbi request reprint Analysis of ehrlichial p28 gene expression in a murine model of persistent infection
    Patricia A Crocquet-Valdes
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Ann N Y Acad Sci 1063:420-4. 2005
    ..A model of persistent infection was described and provided tools for study of persistent ehrlichial infection. We completed the sequence of the E. muris p28 locus and examined mRNA expression...
  54. ncbi request reprint Restriction and expansion of Ehrlichia strain diversity
    XUE JIE YU
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Sealy Center for Vaccine Development, University of Texas Medical Branch, Galveston, TX 77555 0609, United States
    Vet Parasitol 143:337-46. 2007
    ..canis suggests that E. chaffeensis and E. ruminantium face more host immune pressure than E. canis or that E. chaffeensis and E. ruminantium evolved earlier than E. canis and have diverged...
  55. pmc An intradermal environment promotes a protective type-1 response against lethal systemic monocytotropic ehrlichial infection
    Heather L Stevenson
    Department of Pathology and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas 77555 0609, USA
    Infect Immun 74:4856-64. 2006
    ....
  56. ncbi request reprint Overcoming barriers to the transformation of the genus Ehrlichia
    S Wesley Long
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Ann N Y Acad Sci 1063:403-10. 2005
    ..muris. Application of these techniques should allow for a wide variety of molecular studies to be performed that were previously impossible. This heralds the beginning of a new era in ehrlichial research...
  57. pmc Ehrlichia chaffeensis: a prevalent, life-threatening, emerging pathogen
    David H Walker
    Department of Pathology, University of Texas Medical Branch, World Health OrganizationCollaborating Center for Tropical Diseases, UTMB Center for Biodefense and EmergingInfectious Diseases, Galveston, Texas 77555 0609
    Trans Am Clin Climatol Assoc 115:375-82; discussion 382-4. 2004
    ..Protection against fatal ehrlichiosis was achieved by prior infection with low virulence E. muris. Acute clinical diagnosis is difficult except by PCR. Response to doxycycline is dramatic...
  58. doi request reprint Diagnosing emerging and reemerging infectious diseases: the pivotal role of the pathologist
    Juan P Olano
    Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 0428, USA
    Arch Pathol Lab Med 135:83-91. 2011
    ..Nanobiotechnology is beginning to impact laboratory diagnostics in the clinical setting...
  59. pmc Infection of the endothelium by members of the order Rickettsiales
    Gustavo Valbuena
    Department of Pathology and Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555 0609, USA
    Thromb Haemost 102:1071-9. 2009
    ..The study of these bacteria in relevant in vivo models is likely to offer new insights into the physiology of the endothelium that have not been revealed by other models...
  60. pmc CD4+ CD25+ Foxp3- T-regulatory cells produce both gamma interferon and interleukin-10 during acute severe murine spotted fever rickettsiosis
    Rong Fang
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 77:3838-49. 2009
    ....
  61. pmc Amino acid biosynthesis deficiency in bacteria associated with human and animal hosts
    XUE JIE YU
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, United States
    Infect Genet Evol 9:514-7. 2009
    ..The extent of genome reduction appears to depend on the environment in which they reside. The richer the nutrients are in the environment the smaller the genome is in the bacteria...
  62. pmc Rickettsiae stimulate dendritic cells through toll-like receptor 4, leading to enhanced NK cell activation in vivo
    Jeffrey M Jordan
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    J Infect Dis 199:236-42. 2009
    ..Last, adoptive transfer of rickettsiae-exposed, TLR4-stimulated DCs activated NK cells in vivo. Together, these data reveal an important role for DCs in recognizing rickettsiae through TLR4 and inducing early antirickettsial immunity...
  63. pmc Progress and obstacles in vaccine development for the ehrlichioses
    Jere W McBride
    Department of Pathology, Center for Emerging Infectious Diseases and Biodefense, Sealy Center for Vaccine Development, and the Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Expert Rev Vaccines 9:1071-82. 2010
    ....
  64. ncbi request reprint The endothelium as a target for infections
    Gustavo Valbuena
    School of Medicine, Universidad de Los Andes, Bogota, Colombia
    Annu Rev Pathol 1:171-98. 2006
    ..This article defines criteria for considering an infection as truly endothelium-targeted and reviews the literature that offers insights into the pathogenesis of human endothelial-target infections...
  65. pmc Amblyomma imitator ticks as vectors of Rickettsia rickettsii, Mexico
    Karla A Oliveira
    University of Texas Medical Branch at Galveston, Galveston, Texas 77555 0609, USA
    Emerg Infect Dis 16:1282-4. 2010
    ..Sequence analyses of 17-kD common antigen and outer membrane protein A and B gene fragments showed to it to be R. rickettsii, which suggested a potential new vector for this bacterium...
  66. pmc Relative importance of T-cell subsets in monocytotropic ehrlichiosis: a novel effector mechanism involved in Ehrlichia-induced immunopathology in murine ehrlichiosis
    Nahed Ismail
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, 301 University Blvd, Galveston, TX 77555 0609, USA
    Infect Immun 75:4608-20. 2007
    ..Our data demonstrate a novel mechanism of immunopathology in which CD8(+) T cells mediate Ehrlichia-induced toxic shock, which is associated with IL-10 overproduction and CD4(+) T-cell apoptosis...
  67. ncbi request reprint The developmental cycle of Ehrlichia chaffeensis in vertebrate cells
    Jian Zhi Zhang
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Cell Microbiol 9:610-8. 2007
    ..We conclude that E. chaffeensis has a developmental cycle, in which the DC attaches to and enters into the host cells, and transforms into RC and the RC multiplies by binary fission for 48 h and then matures into DC at 72 h...
  68. ncbi request reprint Effect of blocking the CXCL9/10-CXCR3 chemokine system in the outcome of endothelial-target rickettsial infections
    Gustavo Valbuena
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Am J Trop Med Hyg 71:393-9. 2004
    ....
  69. pmc Human monocytotropic ehrlichiosis, Missouri
    Juan P Olano
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0747, USA
    Emerg Infect Dis 9:1579-86. 2003
    ..HME is a prevalent, potentially severe disease in southeastern Missouri that often requires hospitalization. Because clinical presentation of HME is nonspecific, PCR is useful in the diagnosis of acute HME...
  70. pmc Fc-dependent polyclonal antibodies and antibodies to outer membrane proteins A and B, but not to lipopolysaccharide, protect SCID mice against fatal Rickettsia conorii infection
    Hui Min Feng
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555, USA
    Infect Immun 72:2222-8. 2004
    ..Antibodies might be useful for treating infections with antibiotic-resistant organisms, and some B-cell epitopes should be included in a subunit vaccine...
  71. pmc Effect of antibody on the rickettsia-host cell interaction
    Hui Min Feng
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 72:3524-30. 2004
    ..conorii infection of endothelium and macrophages by opsonization that inhibited phagosomal escape and resulted in phagolysosomal killing mediated by nitric oxide, reactive oxygen intermediates, and L-tryptophan starvation...
  72. ncbi request reprint Rickettsiae-stimulated dendritic cells mediate protection against lethal rickettsial challenge in an animal model of spotted fever rickettsiosis
    Jeffrey M Jordan
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
    J Infect Dis 196:629-38. 2007
    ..Taken together, our data suggest that a vigorous proinflammatory response in DCs is associated with protective immunity to rickettsiae and that generation of antigen-specific immunity is crucial to complete protection...
  73. ncbi request reprint Novel Immunoreactive glycoprotein orthologs of Ehrlichia spp
    Jere W McBride
    Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:678-84. 2003
    ..The chromosomal location, amino acid homology, and biophysical properties support the conclusion that the p153 and p156 glycoproteins (designated gp200s) are species-specific immunoreactive orthologs...
  74. ncbi request reprint T cells mediate cross-protective immunity between spotted fever group rickettsiae and typhus group rickettsiae
    Gustavo Valbuena
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    J Infect Dis 190:1221-7. 2004
    ..Furthermore, we present evidence that T cells are responsible for this cross-immunity and that cross-stimulation of T cells also occurs in humans...
  75. pmc Kinetics of antibody response to Ehrlichia canis immunoreactive proteins
    Jere W McBride
    Department of Pathology, Sealy Center for Vaccine Development, and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 71:2516-24. 2003
    ..Immunoreactivity and antibody response kinetics suggest that major immunoreactive proteins identified are immunodominant, but early recognition suggests increased dominance by some antigens...
  76. ncbi request reprint Cardiac arrest on induction of anesthesia due to triple vessel coronary artery disease despite a "Negative" angiogram
    Rashmi N Mueller
    Department of Anesthesiology, The University of Texas Medical Branch, Galveston 77555, USA
    Anesthesiology 97:745-9. 2002
  77. pmc Identification and functional analysis of an immunoreactive DsbA-like thio-disulfide oxidoreductase of Ehrlichia spp
    Jere W McBride
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 70:2700-3. 2002
    ..Recombinant Ehrlichia Dsb (eDsb) proteins were recognized by sera from E. canis-infected dogs but not from E. chaffeensis-infected patients. The eDsb proteins were observed primarily in the periplasm of E. chaffeensis and E. canis...
  78. ncbi request reprint Ultrastructural evidence of the ehrlichial developmental cycle in naturally infected Ixodes persulcatus ticks in the course of coinfection with Rickettsia, Borrelia, and a flavivirus
    Vsevolod L Popov
    Department of Pathology, The University of Texas Medical Branch, Center for Biodefense and Emerging Infectious Diseases, Galveston, Texas 77555, USA
    Vector Borne Zoonotic Dis 7:699-716. 2007
    ..This is the first demonstration of E. muris, "R. tarasevichiae," and the ehrlichial developmental cycle in naturally infected I. persulcatus sticks...
  79. pmc Clinical manifestations, epidemiology, and laboratory diagnosis of human monocytotropic ehrlichiosis in a commercial laboratory setting
    Juan P Olano
    Department of Pathology, University of Texas Medical Branch, Center for Biodefense and Emerging Infectious Diseases, Galveston, Texas 77555 0609, USA
    Clin Diagn Lab Immunol 10:891-6. 2003
    ..The clinical and laboratory information from 41 patients provides insight into the epidemiological, clinical, and laboratory characteristics of HME...
  80. pmc Detection of medically important Ehrlichia by quantitative multicolor TaqMan real-time polymerase chain reaction of the dsb gene
    C Kuyler Doyle
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    J Mol Diagn 7:504-10. 2005
    ..This assay provides a powerful tool for prospective medical diagnosis for human and canine ehrlichioses and for ecologic and epidemiological studies involving arthropod and mammalian hosts...
  81. ncbi request reprint Cross-protection between distantly related spotted fever group rickettsiae
    Hui Min Feng
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Vaccine 21:3901-5. 2003
    ....
  82. pmc Identification of CD8 T-lymphocyte epitopes in OmpB of Rickettsia conorii
    Zhen Li
    Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch at Galveston, Galveston, Texas 77555 0609, USA
    Infect Immun 71:3920-6. 2003
    ..Significantly higher levels of specific cytotoxic T-lymphocyte killing were observed with the same three synthetic peptides, SKGVNVDTV (OmpB(708-716)), ANSTLQIGG (OmpB(789-797)), and IVEFVNTGP (OmpB(812-820))...
  83. pmc Regulatory roles of CD1d-restricted NKT cells in the induction of toxic shock-like syndrome in an animal model of fatal ehrlichiosis
    H L Stevenson
    Department of Pathology and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555 0609, USA
    Infect Immun 76:1434-44. 2008
    ..In conclusion, our data suggest that NKT cells mediate Ehrlichia-induced T-cell-mediated toxic shock-like syndrome, most likely via cognate and noncognate interactions with antigen-presenting cells...
  84. ncbi request reprint Fatal neonatal echovirus 6 infection: autopsy case report and review of the literature
    K C Ventura
    Department of Pathology, University of Texas Medical Branch, Galveston 77555, USA
    Mod Pathol 14:85-90. 2001
    ..Echovirus type 6 was isolated from blood, liver, and lungs. Although uncommon, echovirus type 6 infection may produce a spectrum of pathologic findings similar to those seen with the more commonly virulent echovirus type 11...
  85. pmc Emergence of the ehrlichioses as human health problems
    D H Walker
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Emerg Infect Dis 2:18-29. 1996
    ....
  86. pmc Detection of infection or infectious agents by use of cytologic and histologic stains
    G L Woods
    Department of Pathology, University of Texas Medical Branch, Galveston, 77555 0743, USA
    Clin Microbiol Rev 9:382-404. 1996
    ....
  87. ncbi request reprint Molecular characterization of the 28 kDa multigene locus of Ehrlichia muris
    Patricia A Crocquet-Valdes
    Department of Pathology, Sealy Center for Vaccine Development, and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Ann N Y Acad Sci 990:714-6. 2003
  88. ncbi request reprint Mechanisms of immunity against rickettsiae. New perspectives and opportunities offered by unusual intracellular parasites
    Gustavo Valbuena
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston 77555 0609, USA
    Microbes Infect 4:625-33. 2002
    ....
  89. pmc Emerging pathogens: challenges and successes of molecular diagnostics
    Jianli Dong
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA
    J Mol Diagn 10:185-97. 2008
    ..The ongoing challenge to the field of molecular diagnostics is to apply contemporary knowledge to facilitate agent diagnosis as well as to further discoveries of novel pathogens...
  90. ncbi request reprint Expression of CX3CL1 (fractalkine) in mice with endothelial-target rickettsial infection of the spotted-fever group
    Gustavo Valbuena
    Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555 0609, USA
    Virchows Arch 446:21-7. 2005
    ..The peak of expression of fractalkine on day 3 of infection coincided with the time of infiltration of macrophages into infected tissues and preceded the peak of rickettsial content in tissues...
  91. pmc Genotyping Rickettsia prowazekii isolates
    Yong Zhu
    University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Emerg Infect Dis 14:1300-2. 2008
    ..This method can be used to type and trace the origin of R. prowazekii isolated from samples collected during epidemics after a bioterrorism attack...
  92. pmc Rickettsia species infecting Amblyomma cooperi ticks from an area in the state of São Paulo, Brazil, where Brazilian spotted fever is endemic
    Marcelo B Labruna
    Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    J Clin Microbiol 42:90-8. 2004
    ..These results do not support the role of A. cooperi in the ecology of R. rickettsii in the area studied, but they add two more species of rickettsiae to the poorly developed list of species occurring in ticks in South America...
  93. ncbi request reprint Sequence analysis of the 190-kDa antigen-encoding gene of Rickettsia conorii (Malish 7 strain)
    P A Crocquet-Valdes
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609
    Gene 140:115-9. 1994
    ..The conservation of rompA across several pathogenic spotted fever group (SFG) rickettsial species suggests that it may be a potential candidate for use as a subunit vaccine for SFG rickettsial diseases...
  94. pmc Cloning, sequencing, and expression of the gene coding for an antigenic 120-kilodalton protein of Rickettsia conorii
    K W Schuenke
    Department of Pathology, University of Texas Medical Branch, Galveston 77555 0609
    Infect Immun 62:904-9. 1994
    ..A 75-kDa portion of the 120-kDa antigen was overexpressed in and purified from Escherichia coli. This polypeptide was recognized by antirickettsial antibodies and may be a useful diagnostic reagent for spotted fever group rickettsioses...
  95. ncbi request reprint Rocky Mountain spotted fever--changing ecology and persisting virulence
    J Stephen Dumler
    Division of Medical Microbiology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, USA
    N Engl J Med 353:551-3. 2005
  96. ncbi request reprint A mutation inactivating the methyltransferase gene in avirulent Madrid E strain of Rickettsia prowazekii reverted to wild type in the virulent revertant strain Evir
    Jian Zhi Zhang
    Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    Vaccine 24:2317-23. 2006
    ..We conclude that the mutation in the E strain gene reverts to wild type in the virulent revertant Evir strain. Whether the mutation plays an essential role in the attenuation of E strain needs to be further investigated...
  97. ncbi request reprint Detection of Rickettsia felis in a New World flea species, Anomiopsyllus nudata (Siphonaptera: Ctenophthalmidae)
    Heather L Stevenson
    Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555 0609, USA
    J Med Entomol 42:163-7. 2005
    ..felis. This work comprises the first report of R. felis detection in a flea species (A. nudata) endemic to the New World...
  98. pmc Antigenic variation of Ehrlichia chaffeensis resulting from differential expression of the 28-kilodalton protein gene family
    S Wesley Long
    Department of Pathology and WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas 77555 0609, USA
    Infect Immun 70:1824-31. 2002
    ..chaffeensis 28-kDa proteins may result from differential expression of the p28 gene family members rather than gene conversion...
  99. ncbi request reprint Human ehrlichioses in Brazil: first suspect cases
    Simone B Calic
    Ezequiel Dias Foundation, Belo Horizonte, Brazil
    Braz J Infect Dis 8:259-62. 2004
    ..The differential diagnosis was made at the Minas Gerais Rickettsiosis Public Health Laboratory. The clinical and laboratory findings, with positive serology for the HME agent, indicated suspected cases of human ehrlichioses in Brazil...
  100. ncbi request reprint [Emerging and reemerging rickettsiosis in an endemic area of Minas Gerais State, Brazil]
    Marcio A M Galvao
    Departamento de Nutrição Clínica e Social, Escola de Nutrição, Universidade Federal de Ouro Preto, Ouro Preto, MG, 35400 000, Brasil
    Cad Saude Publica 18:1593-7. 2002
    ..81%), respectively. The results in schoolchildren and the presence of canine seroreactivity to Ehrlichiaspecies that are potentially pathogenic to humans suggests the risk of transmission of other Rickettsiaein the study area...
  101. ncbi request reprint Detection of Rickettsia rickettsii in the tick Amblyomma cajennense in a new Brazilian spotted fever-endemic area in the state of Minas Gerais
    Elizângela Guedes
    Departamento de Medicina Veterinaria Preventiva, Escola de Veterinaria, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
    Mem Inst Oswaldo Cruz 100:841-5. 2005
    ..rickettsii has been previously reported infecting A. cajennense ticks in Brazil and other Latin American countries, the present study performed the first molecular characterization of R. rickettsii from the tick A. cajennense...

Research Grants43

  1. SPOTTED FEVER RICKETTSIAL ANTIGENS
    David H Walker; Fiscal Year: 2010
    ..This project is designed to determine what components of the immune response are responsible for failure to control bacterial growth in fatal infections to allow future immunomodulatory treatment to enhance survival. ..
  2. EHRLICHIA CHAFFEENSIS SURFACE PROTEINS
    David Walker; Fiscal Year: 2004
    ....
  3. SPOTTED FEVER RICKETTSIAL ANTIGENS
    David Walker; Fiscal Year: 2003
    ....
  4. Gammacell-220 Excel Refurbished Research Irradiator
    David Walker; Fiscal Year: 2006
    ....
  5. Region VI Center for Biodefence and Emerging Infections
    David Walker; Fiscal Year: 2007
    ..abstract_text> ..
  6. Ehrlichia chaffeensis protective proteins
    David H Walker; Fiscal Year: 2010
    ..chaffeensis. ..
  7. Ehrlichia chaffeensis protective proteins
    David Walker; Fiscal Year: 2009
    ..chaffeensis. ..
  8. Vaccine for Epidemic Typhus
    David Walker; Fiscal Year: 2007
    ..This effective epidemic typhus vaccine may be effective for other rickettsial diseases because of the cross-reactive antigens among the rickettsiae. ..
  9. Spotted Fever Rickettesial Antigens
    David Walker; Fiscal Year: 2007
    ..abstract_text> ..
  10. Ehrlichia chaffeensis protective proteins
    David Walker; Fiscal Year: 2007
    ..chaffeensis. ..
  11. EHRLICHIA CHAFFEENSIS SURFACE PROTEINS
    David Walker; Fiscal Year: 2001
    ....
  12. EHRLICHIA CHAFFEENSIS SURFACE PROTEINS
    David Walker; Fiscal Year: 1999
    ..Toward the goal of elucidating the pathogenesis of E. chaffeensis infection, a series of studies are designed to identify the E. chaffeensis adhesin for the human and canine monocyte/macrophage. ..
  13. ANTIGENIC COMPOSITION OF MEDICALLY RELATED EHRLICHIAE
    David Walker; Fiscal Year: 1993
    ....
  14. ANALYSIS OF SPOTTED FEVER RICKETTSIAL ANTIGENS
    David Walker; Fiscal Year: 1993
    ..australis), Israel tick typhus (unnamed Rickettsia sp.), and the recognized Oriental spotted fever (R. japonica) comprise scientifically and medically important diseases that offer a fertile focus of investigation...
  15. ANALYSIS OF SPOTTED FEVER RICKETTSIAL ANTIGENS
    David Walker; Fiscal Year: 1991
    ....