ehrlichia chaffeensis

Summary

Summary: A species of gram-negative bacteria that is the causative agent of human EHRLICHIOSIS. This organism was first discovered at Fort Chaffee, Arkansas, when blood samples from suspected human ehrlichiosis patients were studied.

Top Publications

  1. Varela A, Stallknecht D, Yabsley M, Moore V, Howerth E, Davidson W, et al. Primary and secondary infection with Ehrlichia chaffeensis in white-tailed deer (Odocoileus virginianus). Vector Borne Zoonotic Dis. 2005;5:48-57 pubmed
    White-tailed deer (Odocoileus virginianus) are the principal reservoir host for Ehrlichia chaffeensis, causative agent of human monocytic ehrlichiosis (HME). Because white-tailed deer maintain a long-term infection with E...
  2. Cheng Z, Wang X, Rikihisa Y. Regulation of type IV secretion apparatus genes during Ehrlichia chaffeensis intracellular development by a previously unidentified protein. J Bacteriol. 2008;190:2096-105 pubmed publisher
    ..In the rickettsial pathogen Ehrlichia chaffeensis, the virBD genes are split into two operons, the virB3-virB6 (preceded by sodB) and virB8-virD4 operons...
  3. Rikihisa Y. Ehrlichia subversion of host innate responses. Curr Opin Microbiol. 2006;9:95-101 pubmed
    Anaplasma (formerly Ehrlichia) phagocytophilum and Ehrlichia chaffeensis, upon infection of humans, replicate in host leukocyte granulocytes and monocytes/macrophages, respectively...
  4. Zhang J, Popov V, Gao S, Walker D, YU X. The developmental cycle of Ehrlichia chaffeensis in vertebrate cells. Cell Microbiol. 2007;9:610-8 pubmed
    b>Ehrlichia chaffeensis, an obligatory intracellular bacterium, has two forms in mammalian cells: small dense-cored cells (DC) with dense nucleoid and larger reticulate cells (RC) with uniformly dispersed nucleoid...
  5. Wakeel A, Kuriakose J, McBride J. An Ehrlichia chaffeensis tandem repeat protein interacts with multiple host targets involved in cell signaling, transcriptional regulation, and vesicle trafficking. Infect Immun. 2009;77:1734-45 pubmed publisher
    b>Ehrlichia chaffeensis is an obligately intracellular bacterium that exhibits tropism for mononuclear phagocytes forming cytoplasmic membrane-bound microcolonies called morulae. To survive and replicate within phagocytes, E...
  6. Singu V, Peddireddi L, Sirigireddy K, Cheng C, Munderloh U, Ganta R. Unique macrophage and tick cell-specific protein expression from the p28/p30-outer membrane protein multigene locus in Ehrlichia chaffeensis and Ehrlichia canis. Cell Microbiol. 2006;8:1475-87 pubmed
    b>Ehrlichia chaffeensis and Ehrlichia canis are tick-transmitted rickettsial pathogens that cause human and canine monocytic ehrlichiosis respectively...
  7. Peddireddi L, Cheng C, Ganta R. Promoter analysis of macrophage- and tick cell-specific differentially expressed Ehrlichia chaffeensis p28-Omp genes. BMC Microbiol. 2009;9:99 pubmed publisher
    b>Ehrlichia chaffeensis is a rickettsial agent responsible for an emerging tick-borne illness, human monocytic ehrlichiosis. Recently, we reported that E...
  8. Li J, Winslow G. Survival, replication, and antibody susceptibility of Ehrlichia chaffeensis outside of host cells. Infect Immun. 2003;71:4229-37 pubmed
    b>Ehrlichia chaffeensis, an obligate intracellular, tick-transmitted bacterium, is susceptible to antibody-mediated host defense, but the mechanism by which this occurs is not understood...
  9. Ndip L, Ndip R, Esemu S, Walker D, McBride J. Predominance of Ehrlichia chaffeensis in Rhipicephalus sanguineus ticks from kennel-confined dogs in Limbe, Cameroon. Exp Appl Acarol. 2010;50:163-8 pubmed publisher
    ..b>Ehrlichia chaffeensis DNA was detected in 33 (56%) ticks, E...

More Information

Publications93

  1. Olano J, Walker D. Human ehrlichioses. Med Clin North Am. 2002;86:375-92 pubmed
  2. Ohashi N, Zhi N, Zhang Y, Rikihisa Y. Immunodominant major outer membrane proteins of Ehrlichia chaffeensis are encoded by a polymorphic multigene family. Infect Immun. 1998;66:132-9 pubmed
    ..immunodominant major proteins ranging from 23 to 30 kDa were identified in the outer membrane fractions of Ehrlichia chaffeensis and Ehrlichia canis. The N-terminal amino acid sequence of a 28-kDa protein of E...
  3. Ge Y, Rikihisa Y. Surface-exposed proteins of Ehrlichia chaffeensis. Infect Immun. 2007;75:3833-41 pubmed
    The surface proteins of Ehrlichia chaffeensis provide an important interface for pathogen-host interactions. To investigate the surface proteins of E...
  4. Lee S, Na D, Kim C, Li Y, Cho Y, Park J, et al. Identification and prevalence of Ehrlichia chaffeensis infection in Haemaphysalis longicornis ticks from Korea by PCR, sequencing and phylogenetic analysis based on 16S rRNA gene. J Vet Sci. 2005;6:151-5 pubmed
    ..This is the first study to report molecular detection and phylogenetic analysis of E. chaffeensis from H. longicornis ticks in Korea. The implicit significance of E. chaffeensis infection in H. longicornis ticks in Korea is discussed. ..
  5. Yabsley M, Wimberly M, Stallknecht D, Little S, Davidson W. Spatial analysis of the distribution of Ehrlichia chaffeensis, causative agent of human monocytotropic ehrlichiosis, across a multi-state region. Am J Trop Med Hyg. 2005;72:840-50 pubmed
    b>Ehrlichia chaffeensis, which causes human monocytotrophic ehrlichiosis (HME), is an important emerging tick-borne pathogen in the southeastern and southcentral United States. The endemnicity probability of E...
  6. da Costa P, Valle L, Brigatte M, Greco D. More about human monocytotropic ehrlichiosis in Brazil: serological evidence of nine new cases. Braz J Infect Dis. 2006;10:7-10 pubmed
    Human Ehrlichia chaffeensis infections have been reported in North America, Asia and Europe, but only recently have human cases been reported in Brazil. Nine new human cases of E...
  7. Dedonder S, Cheng C, Willard L, Boyle D, Ganta R. Transmission electron microscopy reveals distinct macrophage- and tick cell-specific morphological stages of Ehrlichia chaffeensis. PLoS ONE. 2012;7:e36749 pubmed publisher
    b>Ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis...
  8. Davidson W, Lockhart J, Stallknecht D, Howerth E, Dawson J, Rechav Y. Persistent Ehrlichia chaffeensis infection in white-tailed deer. J Wildl Dis. 2001;37:538-46 pubmed
    ..deer (Odocoileus virginianus) were inoculated intravenously with a deer-origin isolate (15B-WTD-GA) of Ehrlichia chaffeensis. The course of infection was monitored using indirect fluorescent antibody (IFA), polymerase chain ..
  9. Von Ohlen T, Luce Fedrow A, Ortega M, Ganta R, Chapes S. Identification of critical host mitochondrion-associated genes during Ehrlichia chaffeensis infections. Infect Immun. 2012;80:3576-86 pubmed publisher
    b>Ehrlichia chaffeensis is an obligate intracellular bacterium that causes human monocytic ehrlichiosis (HME)...
  10. Kumagai Y, Huang H, Rikihisa Y. Expression and porin activity of P28 and OMP-1F during intracellular Ehrlichia chaffeensis development. J Bacteriol. 2008;190:3597-605 pubmed publisher
    b>Ehrlichia chaffeensis, an obligatory intracellular gram-negative bacterium, must take up various nutrients and metabolic compounds because it lacks many genes involved in metabolism...
  11. Rikihisa Y. Anaplasma phagocytophilum and Ehrlichia chaffeensis: subversive manipulators of host cells. Nat Rev Microbiol. 2010;8:328-39 pubmed publisher
    ..and Ehrlichia spp. cause several emerging human infectious diseases. Anaplasma phagocytophilum and Ehrlichia chaffeensis are transmitted between mammals by blood-sucking ticks and replicate inside mammalian white blood cells ..
  12. Manangan J, Schweitzer S, Nibbelink N, Yabsley M, Gibbs S, Wimberly M. Habitat factors influencing distributions of Anaplasma phagocytophilum and Ehrlichia chaffeensis in the Mississippi Alluvial Valley. Vector Borne Zoonotic Dis. 2007;7:563-73 pubmed
    Human monocytotropic ehrlichiosis (HME), caused by the bacterium Ehrlichia chaffeensis, and human granulocytic anaplasmosis (HGA), caused by the bacterium Anaplasma phagocytophilum, are two emerging tick-borne zoonoses of concern...
  13. Wen B, Jian R, Zhang Y, Chen R. Simultaneous detection of Anaplasma marginale and a new Ehrlichia species closely related to Ehrlichia chaffeensis by sequence analyses of 16S ribosomal DNA in Boophilus microplus ticks from Tibet. J Clin Microbiol. 2002;40:3286-90 pubmed
    ..The other sequence was most similar to that of the gene of Ehrlichia chaffeensis, an etiological agent of human monocytic ehrlichiosis...
  14. McBride J, Doyle C, Zhang X, Cardenas A, Popov V, Nethery K, et al. Identification of a glycosylated Ehrlichia canis 19-kilodalton major immunoreactive protein with a species-specific serine-rich glycopeptide epitope. Infect Immun. 2007;75:74-82 pubmed
    ..characterization of this highly conserved 19-kDa major immunoreactive glycoprotein (gp19) ortholog of the Ehrlichia chaffeensis variable-length PCR target (VLPT) protein. E...
  15. Ganta R, Wilkerson M, Cheng C, Rokey A, Chapes S. Persistent Ehrlichia chaffeensis infection occurs in the absence of functional major histocompatibility complex class II genes. Infect Immun. 2002;70:380-8 pubmed
    Human monocytic ehrlichiosis is an emerging tick-borne disease caused by the rickettsia Ehrlichia chaffeensis. We investigated the impact of two genes that control macrophage and T-cell function on murine resistance to E. chaffeensis...
  16. Standaert S, Yu T, Scott M, Childs J, Paddock C, Nicholson W, et al. Primary isolation of Ehrlichia chaffeensis from patients with febrile illnesses: clinical and molecular characteristics. J Infect Dis. 2000;181:1082-8 pubmed
    b>Ehrlichia chaffeensis was sought among patients with a history of tick exposure and fever, and the accuracy of other diagnostic tests was compared with that of primary isolation. Among the 38 patients enrolled, E...
  17. Bao W, Kumagai Y, Niu H, Yamaguchi M, Miura K, Rikihisa Y. Four VirB6 paralogs and VirB9 are expressed and interact in Ehrlichia chaffeensis-containing vacuoles. J Bacteriol. 2009;191:278-86 pubmed publisher
    ..to several virB genes and virD4 of Agrobacterium tumefaciens are found in an intravacuolar pathogen Ehrlichia chaffeensis, the tick-borne causative agent of human monocytic ehrlichiosis...
  18. Yabsley M. Natural history of Ehrlichia chaffeensis: vertebrate hosts and tick vectors from the United States and evidence for endemic transmission in other countries. Vet Parasitol. 2010;167:136-48 pubmed publisher
    b>Ehrlichia chaffeensis, an intracellular gram-negative zoonotic bacterium, is the causative agent of human monocytotropic ehrlichiosis (HME)...
  19. Miura K, Matsuo J, Rahman M, Kumagai Y, Li X, Rikihisa Y. Ehrlichia chaffeensis induces monocyte inflammatory responses through MyD88, ERK, and NF-?B but not through TRIF, interleukin-1 receptor 1 (IL-1R1)/IL-18R1, or toll-like receptors. Infect Immun. 2011;79:4947-56 pubmed publisher
    ..hepatitis, is caused by infection of monocytes/macrophages with a lipopolysaccharide-deficient bacterium, Ehrlichia chaffeensis. The E...
  20. Heo E, Park J, Koo J, Park M, Park M, Dumler J, et al. Serologic and molecular detection of Ehrlichia chaffeensis and Anaplasma phagocytophila (human granulocytic ehrlichiosis agent) in Korean patients. J Clin Microbiol. 2002;40:3082-5 pubmed
    Sera from 491 Korean patients with acute febrile diseases were tested for Ehrlichia chaffeensis and Anaplasma phagocytophila antibodies by indirect immunofluorescence assay (IFA), Western blotting, and TaqMan real-time PCR. Overall, 0...
  21. Paddock C, Folk S, Shore G, Machado L, Huycke M, Slater L, et al. Infections with Ehrlichia chaffeensis and Ehrlichia ewingii in persons coinfected with human immunodeficiency virus. Clin Infect Dis. 2001;33:1586-94 pubmed
    ..course and laboratory evaluation of 21 patients coinfected with human immunodeficiency virus (HIV) and Ehrlichia chaffeensis or Ehrlichia ewingii are reviewed and summarized, including 13 cases of ehrlichiosis caused by E...
  22. Reddy G, Streck C. Variability in the 28-kDa surface antigen protein multigene locus of isolates of the emerging disease agent Ehrlichia chaffeensis suggests that it plays a role in immune evasion. Mol Cell Biol Res Commun. 1999;1:167-75 pubmed
    ..locus encoding 28 kDa surface antigen proteins (28 kDa SAPs) for two closely related rickettsials, Ehrlichia chaffeensis and Ehrlichia canis (Reddy, G. R., et al. (1998) Biochem. Biophys. Res. Commun...
  23. Felek S, Unver A, Stich R, Rikihisa Y. Sensitive detection of Ehrlichia chaffeensis in cell culture, blood, and tick specimens by reverse transcription-PCR. J Clin Microbiol. 2001;39:460-3 pubmed
    b>Ehrlichia chaffeensis is an obligatory intracellular bacterium of monocytes and macrophages and the etiologic agent of human monocytic ehrlichiosis, an emerging zoonosis...
  24. Dawson J, Paddock C, Warner C, Greer P, Bartlett J, Ewing S, et al. Tissue diagnosis of Ehrlichia chaffeensis in patients with fatal ehrlichiosis by use of immunohistochemistry, in situ hybridization, and polymerase chain reaction. Am J Trop Med Hyg. 2001;65:603-9 pubmed
    ..human ehrlichiosis is a complex of emerging tick-borne diseases caused by 3 distinct Ehrlichia species: Ehrlichia chaffeensis, Ehrlichia ewingii, and the human granulocytotropic ehrlichiosis agent...
  25. Park J, Heo E, Choi K, Dumler J, Chae J. Detection of antibodies to Anaplasma phagocytophilum and Ehrlichia chaffeensis antigens in sera of Korean patients by western immunoblotting and indirect immunofluorescence assays. Clin Diagn Lab Immunol. 2003;10:1059-64 pubmed
    ..to detect antibodies against Anaplasma phagocytophilum (the human granulocytic ehrlichiosis agent) and Ehrlichia chaffeensis (the human monocytic ehrlichiosis agent) by indirect fluorescent-antibody assay (IFA) and the Western blot ..
  26. Dahlgren F, Mandel E, Krebs J, Massung R, McQuiston J. Increasing incidence of Ehrlichia chaffeensis and Anaplasma phagocytophilum in the United States, 2000-2007. Am J Trop Med Hyg. 2011;85:124-31 pubmed publisher
    b>Ehrlichia chaffeensis causes human monocytic ehrlichiosis, and Anaplasma phagocytophilum causes human granulocytic anaplasmosis. These related tick-borne rickettsial organisms can cause severe and fatal illness...
  27. Long S, Zhang X, Zhang J, Ruble R, Teel P, YU X. Evaluation of transovarial transmission and transmissibility of Ehrlichia chaffeensis (Rickettsiales: Anaplasmataceae) in Amblyomma americanum (Acari: Ixodidae). J Med Entomol. 2003;40:1000-4 pubmed
    It has long been assumed that Ehrlichia chaffeensis (Anderson, Dawson & Wilson), is not transmitted transovarially in the lone star tick vector Amblyomma americanum (L.)...
  28. Zhang T, Kedzierska Mieszkowska S, Liu H, Cheng C, Ganta R, Zolkiewski M. Aggregate-reactivation activity of the molecular chaperone ClpB from Ehrlichia chaffeensis. PLoS ONE. 2013;8:e62454 pubmed publisher
    Rickettsiale diseases, including human monocytic ehrlichiosis caused by Ehrlichia chaffeensis, are the second leading cause of the tick-borne infections in the USA and a growing health concern. Little is known about how E...
  29. Luo T, Zhang X, Wakeel A, Popov V, McBride J. A variable-length PCR target protein of Ehrlichia chaffeensis contains major species-specific antibody epitopes in acidic serine-rich tandem repeats. Infect Immun. 2008;76:1572-80 pubmed publisher
    b>Ehrlichia chaffeensis and E. canis have a small subset of tandem repeat (TR)-containing proteins that elicit strong host immune responses and are associated with host-pathogen interactions...
  30. Mohan Kumar D, Yamaguchi M, Miura K, Lin M, Los M, Coy J, et al. Ehrlichia chaffeensis uses its surface protein EtpE to bind GPI-anchored protein DNase X and trigger entry into mammalian cells. PLoS Pathog. 2013;9:e1003666 pubmed publisher
    b>Ehrlichia chaffeensis, an obligatory intracellular rickettsial pathogen, enters and replicates in monocytes/macrophages and several non-phagocytic cells. E...
  31. Miura K, Rikihisa Y. Virulence potential of Ehrlichia chaffeensis strains of distinct genome sequences. Infect Immun. 2007;75:3604-13 pubmed
    Human monocytic ehrlichiosis, one of the most frequent life-threatening tick-borne zoonoses, is caused by Ehrlichia chaffeensis that lacks endotoxin and peptidoglycan. While sequence polymorphisms in several genes in E...
  32. Lee M, Yu D, Yoon J, Li Y, Lee J, Park J. Natural co-infection of Ehrlichia chaffeensis and Anaplasma bovis in a deer in South Korea. J Vet Med Sci. 2009;71:101-3 pubmed
    ..White-tailed deer (Odocoileus virginianus) are important hosts for Ehrlichia chaffeensis, Anaplasma phagocytophilum and Anaplasma-like organisms...
  33. Yabsley M, Dugan V, Stallknecht D, Little S, Lockhart J, Dawson J, et al. Evaluation of a prototype Ehrlichia chaffeensis surveillance system using white-tailed deer (Odocoileus virginianus) as natural sentinels. Vector Borne Zoonotic Dis. 2003;3:195-207 pubmed
    The natural history of Ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, includes the lone star tick (LST, Amblyomma americanum) as a vector and white-tailed deer (WTD; Odocoileus virginianus) as both a ..
  34. Li J, Yager E, Reilly M, Freeman C, Reddy G, Reilly A, et al. Outer membrane protein-specific monoclonal antibodies protect SCID mice from fatal infection by the obligate intracellular bacterial pathogen Ehrlichia chaffeensis. J Immunol. 2001;166:1855-62 pubmed
    Previous studies of Ehrlichia chaffeensis infection in the mouse have demonstrated that passive transfer of polyclonal Abs from resistant immunocompetent mice to susceptible SCID mice ameliorated infection and disease, even when Abs were ..
  35. Talbot T, Comer J, Bloch K. Ehrlichia chaffeensis infections among HIV-infected patients in a human monocytic ehrlichiosis-endemic area. Emerg Infect Dis. 2003;9:1123-7 pubmed
    Manifestations of human monocytic ehrlichiosis (HME), a tick-borne infection caused by Ehrlichia chaffeensis, range from asymptomatic disease to fulminant infection and may be particularly severe in persons infected with HIV...
  36. Cheng C, Nair A, Indukuri V, Gong S, Felsheim R, JAWORSKI D, et al. Targeted and random mutagenesis of Ehrlichia chaffeensis for the identification of genes required for in vivo infection. PLoS Pathog. 2013;9:e1003171 pubmed publisher
    b>Ehrlichia chaffeensis is a tick transmitted pathogen responsible for the disease human monocytic ehrlichiosis. Research to elucidate gene function in rickettsial pathogens is limited by the lack of genetic manipulation methods...
  37. Kumagai Y, Matsuo J, Hayakawa Y, Rikihisa Y. Cyclic di-GMP signaling regulates invasion by Ehrlichia chaffeensis of human monocytes. J Bacteriol. 2010;192:4122-33 pubmed publisher
    ..The genome of Ehrlichia chaffeensis, an obligatory intracellular bacterium that causes human monocytic ehrlichiosis, encodes a single protein ..
  38. Wakeel A, Zhu B, YU X, McBride J. New insights into molecular Ehrlichia chaffeensis-host interactions. Microbes Infect. 2010;12:337-45 pubmed publisher
    b>Ehrlichia chaffeensis is an obligately intracellular bacterium that exhibits tropism for mononuclear phagocytes and survives by reprogramming the host cell...
  39. Ganta R, Cheng C, Miller E, McGuire B, Peddireddi L, Sirigireddy K, et al. Differential clearance and immune responses to tick cell-derived versus macrophage culture-derived Ehrlichia chaffeensis in mice. Infect Immun. 2007;75:135-45 pubmed
    Human monocytic ehrlichiosis is caused by a tick-transmitted rickettsia, Ehrlichia chaffeensis. We recently reported that E. chaffeensis grown in tick cells expresses different proteins than bacteria grown in macrophages...
  40. Cao W, Gao Y, Zhang P, Zhang X, Dai Q, Dumler J, et al. Identification of Ehrlichia chaffeensis by nested PCR in ticks from Southern China. J Clin Microbiol. 2000;38:2778-80 pubmed
    A total of 717 ticks collected from southern China were examined by nested PCR for the presence of Ehrlichia chaffeensis. Sixteen (55. 2%) of 29 adult Amblyomma testudinarium ticks and 28 (11.7%) of 240 adult and at least 4...
  41. Rikihisa Y, Lin M, Niu H, Cheng Z. Type IV secretion system of Anaplasma phagocytophilum and Ehrlichia chaffeensis. Ann N Y Acad Sci. 2009;1166:106-11 pubmed publisher
    The intracellular bacterial pathogens Ehrlichia chaffeensis and Anaplasma phagocytophilum have evolved to infect leukocytes and hijack biological compounds and processes of these host defensive cells...
  42. Ohashi N, Rikihisa Y, Unver A. Analysis of transcriptionally active gene clusters of major outer membrane protein multigene family in Ehrlichia canis and E. chaffeensis. Infect Immun. 2001;69:2083-91 pubmed
  43. Massung R, Lee K, Mauel M, Gusa A. Characterization of the rRNA genes of Ehrlichia chaffeensis and Anaplasma phagocytophila. DNA Cell Biol. 2002;21:587-96 pubmed publisher
    The rRNA genes of Ehrlichia chaffeensis and Anaplasma phagocytophila have been analyzed. The 16S rRNA genes were previously characterized for both of these agents...
  44. Holden K, Boothby J, Anand S, Massung R. Detection of Borrelia burgdorferi, Ehrlichia chaffeensis, and Anaplasma phagocytophilum in ticks (Acari: Ixodidae) from a coastal region of California. J Med Entomol. 2003;40:534-9 pubmed
    ..19%) I. pacificus ticks and 5 (8.62%) D. variabilis ticks. Ehrlichia chaffeensis, the causative agent of HME, was detected by nested PCR in just five (0.64%) I...
  45. Paddock C, Sumner J, Shore G, Bartley D, Elie R, McQuade J, et al. Isolation and characterization of Ehrlichia chaffeensis strains from patients with fatal ehrlichiosis. J Clin Microbiol. 1997;35:2496-502 pubmed
    Two new isolates of Ehrlichia chaffeensis (designated Jax and St. Vincent) were obtained from patients with fatal ehrlichial infections. Patients developed characteristic manifestations of severe disease due to E...
  46. Zhu B, Kuriakose J, Luo T, Ballesteros E, Gupta S, Fofanov Y, et al. Ehrlichia chaffeensis TRP120 binds a G+C-rich motif in host cell DNA and exhibits eukaryotic transcriptional activator function. Infect Immun. 2011;79:4370-81 pubmed publisher
    b>Ehrlichia chaffeensis is an obligately intracellular bacterium that modulates host cell gene transcription in the mononuclear phagocyte, but the host gene targets and mechanisms involved in transcriptional modulation are not well-defined...
  47. Winslow G, Yager E, Shilo K, Volk E, Reilly A, Chu F. Antibody-mediated elimination of the obligate intracellular bacterial pathogen Ehrlichia chaffeensis during active infection. Infect Immun. 2000;68:2187-95 pubmed
    ..Here, we examined immunity against infection by Ehrlichia chaffeensis, an obligate intracellular bacterium that causes human monocytic ehrlichiosis...
  48. Kocan A, Levesque G, Whitworth L, Murphy G, Ewing S, Barker R. Naturally occurring Ehrlichia chaffeensis infection in coyotes from Oklahoma. Emerg Infect Dis. 2000;6:477-80 pubmed
    A nested polymerase chain reaction assay was used to determine the presence of Ehrlichia chaffeensis, E. canis, and E. ewingii DNA in blood samples of free-ranging coyotes from central and northcentral Oklahoma...
  49. Marshall G, Jacobs R, Schutze G, Paxton H, Buckingham S, DeVincenzo J, et al. Ehrlichia chaffeensis seroprevalence among children in the southeast and south-central regions of the United States. Arch Pediatr Adolesc Med. 2002;156:166-70 pubmed
    The reported annual incidence of human monocytic ehrlichiosis, which is due to infection with Ehrlichia chaffeensis, is as high as 5.5 per million in some states, but serosurveys suggest much higher infection rates in some populations.
  50. Cheng C, Ganta R. Laboratory maintenance of Ehrlichia chaffeensis and Ehrlichia canis and recovery of organisms for molecular biology and proteomics studies. Curr Protoc Microbiol. 2008;Chapter 3:Unit 3A.1 pubmed publisher
    ..include the human monocytic ehrlichiosis caused by the Amblyomma americanum tick-transmitted bacterium, Ehrlichia chaffeensis; human ewingii ehrlichiosis caused by Ehrlichia ewingii (also transmitted by A...
  51. Unver A, Rikihisa Y, Stich R, Ohashi N, Felek S. The omp-1 major outer membrane multigene family of Ehrlichia chaffeensis is differentially expressed in canine and tick hosts. Infect Immun. 2002;70:4701-4 pubmed
    Sixteen of 22 omp-1 paralogs encoding 28-kDa-range immunodominant outer membrane proteins of Ehrlichia chaffeensis were transcribed in blood monocytes of dogs throughout a 56-day infection period. Only one paralog was transcribed by E...
  52. Zhang X, Zhang J, Long S, Ruble R, YU X. Experimental Ehrlichia chaffeensis infection in beagles. J Med Microbiol. 2003;52:1021-6 pubmed
    ..model for human monocytic ehrlichiosis was used to assess persistent infection and antigenic variation of Ehrlichia chaffeensis. Two beagle dogs were infected subcutaneously with E. chaffeensis Arkansas strain...
  53. Davidson W, Lockhart J, Stallknecht D, Howerth E. Susceptibility of red and gray foxes to infection by Ehrlichia chaffeensis. J Wildl Dis. 1999;35:696-702 pubmed
    ..foxes (Urocyon cinereoargenteus) were evaluated for their susceptibility to experimental infection with Ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis...
  54. Luo T, Kuriakose J, Zhu B, Wakeel A, McBride J. Ehrlichia chaffeensis TRP120 interacts with a diverse array of eukaryotic proteins involved in transcription, signaling, and cytoskeleton organization. Infect Immun. 2011;79:4382-91 pubmed publisher
    b>Ehrlichia chaffeensis is an obligately intracellular bacterium that exhibits tropism for mononuclear phagocytes and survives by evading host cell defense mechanisms. Recently, molecular interactions between E...
  55. Lin M, Rikihisa Y. Ehrlichia chaffeensis downregulates surface Toll-like receptors 2/4, CD14 and transcription factors PU.1 and inhibits lipopolysaccharide activation of NF-kappa B, ERK 1/2 and p38 MAPK in host monocytes. Cell Microbiol. 2004;6:175-86 pubmed
    ..b>Ehrlichia chaffeensis, an obligatory intramonocytic Gram-negative bacterium, causes human monocytic ehrlichiosis...
  56. Rikihisa Y, Lin M. Anaplasma phagocytophilum and Ehrlichia chaffeensis type IV secretion and Ank proteins. Curr Opin Microbiol. 2010;13:59-66 pubmed publisher
    ..b>Ehrlichia chaffeensis AnkA was recently reported to be translocated into host-cell nucleus...
  57. Jaworski D, Bowen C, Wasala N. A white-tailed deer/lone star tick model for studying transmission of Ehrlichia chaffeensis. Vector Borne Zoonotic Dis. 2013;13:193-5 pubmed publisher
    Animal models for Ehrlichia chaffeensis have been unsuccessful in recapitulating the natural disease cycle...
  58. Luo T, Zhang X, McBride J. Major species-specific antibody epitopes of the Ehrlichia chaffeensis p120 and E. canis p140 orthologs in surface-exposed tandem repeat regions. Clin Vaccine Immunol. 2009;16:982-90 pubmed publisher
    b>Ehrlichia chaffeensis and E. canis have a small subset of tandem repeat (TR)-containing protein orthologs, including p120/p140, which elicit strong antibody responses...
  59. Safdar N, Love R, Maki D. Severe Ehrlichia chaffeensis infection in a lung transplant recipient: a review of ehrlichiosis in the immunocompromised patient. Emerg Infect Dis. 2002;8:320-3 pubmed
    ..Of 23 reported cases of ehrlichiosis in immunocompromised patients, organ failure occurred in all patients and 6 (25%) died...
  60. Luce Fedrow A, Von Ohlen T, Boyle D, Ganta R, Chapes S. Use of Drosophila S2 cells as a model for studying Ehrlichia chaffeensis infections. Appl Environ Microbiol. 2008;74:1886-91 pubmed publisher
    b>Ehrlichia chaffeensis is an obligate intracellular bacterium and the causative agent of human monocytic ehrlichiosis...
  61. Huang H, Lin M, Wang X, Kikuchi T, Mottaz H, Norbeck A, et al. Proteomic analysis of and immune responses to Ehrlichia chaffeensis lipoproteins. Infect Immun. 2008;76:3405-14 pubmed publisher
    b>Ehrlichia chaffeensis is an obligately intracellular gram-negative bacterium and is the etiologic agent of human monocytic ehrlichiosis (HME). Although E...
  62. Zhang J, Guo H, Winslow G, YU X. Expression of members of the 28-kilodalton major outer membrane protein family of Ehrlichia chaffeensis during persistent infection. Infect Immun. 2004;72:4336-43 pubmed
    The 28-kDa immunodominant outer membrane proteins (P28 OMPs) of Ehrlichia chaffeensis are encoded by a multigene family. As an indirect measure of the in vivo expression of the members of the p28 multigene family of E...
  63. Sehdev A, Dumler J. Hepatic pathology in human monocytic ehrlichiosis. Ehrlichia chaffeensis infection. Am J Clin Pathol. 2003;119:859-65 pubmed
    b>Ehrlichia chaffeensis causes human monocytic ehrlichiosis (HME) that usually includes fever, myalgias, and pancytopenia and, in 80% to 90% of patients, elevations in serum transaminase levels...
  64. Lopez J, Rivera M, Concha J, Gatica S, Loeffeholz M, Barriga O. [Serologic evidence for human Ehrlichiosis in Chile]. Rev Med Chil. 2003;131:67-70 pubmed
    ..Ehrlichiosis is a non contagious infectious disease, mainly transmitted by thick bites. In 1998, this infection was detected in dogs, for the first time, in Chile...
  65. Yager E, Bitsaktsis C, Nandi B, McBride J, Winslow G. Essential role for humoral immunity during Ehrlichia infection in immunocompetent mice. Infect Immun. 2005;73:8009-16 pubmed
    ..Antibodies can protect susceptible SCID mice from fatal Ehrlichia chaffeensis infection, an observation that has been hypothesized to involve the opsonization of bacteria released from ..
  66. Wen B, Cao W, Pan H. Ehrlichiae and ehrlichial diseases in china. Ann N Y Acad Sci. 2003;990:45-53 pubmed
    ..These results reveal that a variety of tick-borne ehrlichial agents and diseases exist in China, and the ehrlichial agents and their tick-vectors are same as or different from that in other countries at species or strain levels...
  67. Kawahara M, Tajima T, Torii H, Yabutani M, Ishii J, Harasawa M, et al. Ehrlichia chaffeensis infection of sika deer, Japan. Emerg Infect Dis. 2009;15:1991-3 pubmed publisher
    To determine whether Ehrlichia chaffeensis exists in Japan, we used PCR to examine blood from sika deer in Nara, Japan. Of 117 deer, 36 (31%) were infected with E. chaffeensis. The E...
  68. Lin M, Rikihisa Y. Obligatory intracellular parasitism by Ehrlichia chaffeensis and Anaplasma phagocytophilum involves caveolae and glycosylphosphatidylinositol-anchored proteins. Cell Microbiol. 2003;5:809-20 pubmed
    Obligatory intracellular, human ehrlichiosis agents Ehrlichia chaffeensis and Anaplasma phagocytophilum create unique replicative compartments devoid of lysosomal markers in monocytes/macrophages and granulocytes respectively...
  69. Faburay B, Liu H, Peddireddi L, Ganta R. Isolation and characterization of Ehrlichia chaffeensis RNA polymerase and its use in evaluating p28 outer membrane protein gene promoters. BMC Microbiol. 2011;11:83 pubmed publisher
    b>Ehrlichia chaffeensis is a tick-transmitted rickettsial pathogen responsible for an important emerging disease, human monocytic ehrlichiosis. To date how E...
  70. Comer J, Nicholson W, Sumner J, Olson J, Childs J. Diagnosis of human ehrlichiosis by PCR assay of acute-phase serum. J Clin Microbiol. 1999;37:31-4 pubmed
    ..residing or having exposure history in Minnesota or Wisconsin, and similarly confirmed products from Ehrlichia chaffeensis were amplified from three individuals from Florida or Maryland...
  71. Rahman M, Cheng Z, Matsuo J, Rikihisa Y. Penicillin-binding protein of Ehrlichia chaffeensis: cytokine induction through MyD88-dependent pathway. J Infect Dis. 2012;206:110-6 pubmed publisher
    Human monocytic ehrlichiosis is one of the most prevalent tick-borne zoonoses caused by infection with Ehrlichia chaffeensis. Although E...
  72. Sumner J, Childs J, Paddock C. Molecular cloning and characterization of the Ehrlichia chaffeensis variable-length PCR target: an antigen-expressing gene that exhibits interstrain variation. J Clin Microbiol. 1999;37:1447-53 pubmed
    A clone expressing an immunoreactive protein with an apparent molecular mass of 44 kDa was selected from an Ehrlichia chaffeensis Arkansas genomic library by probing with anti-E. chaffeensis hyperimmune mouse ascitic fluid...
  73. Yu X, Crocquet Valdes P, Walker D. Cloning and sequencing of the gene for a 120-kDa immunodominant protein of Ehrlichia chaffeensis. Gene. 1997;184:149-54 pubmed
    b>Ehrlichia chaffeensis is the tick-borne, obligately intracellular bacterium that causes human monocytic ehrlichiosis. A 120-kDa protein is one of the immunodominant proteins of E...
  74. Kumagai Y, Cheng Z, Lin M, Rikihisa Y. Biochemical activities of three pairs of Ehrlichia chaffeensis two-component regulatory system proteins involved in inhibition of lysosomal fusion. Infect Immun. 2006;74:5014-22 pubmed
    b>Ehrlichia chaffeensis, the etiologic agent of human monocytic ehrlichiosis, replicates in early endosomes by avoiding lysosomal fusion in monocytes and macrophages. In E...
  75. Lee M, Chae J. Molecular detection of Ehrlichia chaffeensis and Anaplasma bovis in the salivary glands from Haemaphysalis longicornis ticks. Vector Borne Zoonotic Dis. 2010;10:411-3 pubmed publisher
    ..Of total 463 one-side SGs, 56 (12.1%) SGs were positive for Ehrlichia chaffeensis and 11 (2.4%) were positive for Anaplasma bovis. In addition, two (0.4%) SGs were co-infected with both E...
  76. Lin M, Rikihisa Y. Ehrlichia chaffeensis and Anaplasma phagocytophilum lack genes for lipid A biosynthesis and incorporate cholesterol for their survival. Infect Immun. 2003;71:5324-31 pubmed
    b>Ehrlichia chaffeensis and Anaplasma phagocytophilum are agents of human monocytic and granulocytic ehrlichioses, respectively. They are extremely sensitive to mechanical stress and are pleomorphic gram-negative bacteria...
  77. Kumagai Y, Matsuo J, Cheng Z, Hayakawa Y, Rikihisa Y. Cyclic dimeric GMP signaling regulates intracellular aggregation, sessility, and growth of Ehrlichia chaffeensis. Infect Immun. 2011;79:3905-12 pubmed publisher
    ..Replication of an obligatory intracellular pathogen, Ehrlichia chaffeensis, is characterized by formation of bacterial aggregates called morulae inside membrane-bound inclusions...
  78. Cheng Z, Kumagai Y, Lin M, Zhang C, Rikihisa Y. Intra-leukocyte expression of two-component systems in Ehrlichia chaffeensis and Anaplasma phagocytophilum and effects of the histidine kinase inhibitor closantel. Cell Microbiol. 2006;8:1241-52 pubmed
    ..The present study examined TCS in the obligatory intracellular bacteria Ehrlichia chaffeensis and Anaplasma phagocytophilum, that cause human monocytic ehrlichiosis (HME) and human granulocytic ..
  79. Rikihisa Y. Molecular events involved in cellular invasion by Ehrlichia chaffeensis and Anaplasma phagocytophilum. Vet Parasitol. 2010;167:155-66 pubmed publisher
    b>Ehrlichia chaffeensis and Anaplasma phagocytophilum are obligatory intracellular bacteria that preferentially replicate inside leukocytes by utilizing biological compounds and processes of these primary host defensive cells...
  80. Luce Fedrow A, Von Ohlen T, Chapes S. Ehrlichia chaffeensis infections in Drosophila melanogaster. Infect Immun. 2009;77:4815-26 pubmed publisher
    b>Ehrlichia chaffeensis is an obligate, intracellular bacterium, transmitted by the tick Amblyomma americanum, and is the causative agent of human monocytic ehrlichiosis infections. We previously demonstrated that E...
  81. Zhu B, Nethery K, Kuriakose J, Wakeel A, Zhang X, McBride J. Nuclear translocated Ehrlichia chaffeensis ankyrin protein interacts with a specific adenine-rich motif of host promoter and intronic Alu elements. Infect Immun. 2009;77:4243-55 pubmed publisher
    ..Chromatin immunoprecipitation (ChIP) with DNA sequencing revealed an Ehrlichia chaffeensis p200 interaction located within host promoter and intronic Alu-Sx elements, the most abundant repetitive ..
  82. Cheng C, Paddock C, Reddy Ganta R. Molecular heterogeneity of Ehrlichia chaffeensis isolates determined by sequence analysis of the 28-kilodalton outer membrane protein genes and other regions of the genome. Infect Immun. 2003;71:187-95 pubmed
    b>Ehrlichia chaffeensis, a tick-transmitted rickettsial agent, is responsible for human monocytic ehrlichiosis (HME). In this study, we genetically mapped 10 isolates obtained from HME patients...
  83. Yu D, Li Y, Yoon J, Lee J, Lee M, Yu I, et al. Ehrlichia chaffeensis infection in dogs in South Korea. Vector Borne Zoonotic Dis. 2008;8:355-8 pubmed publisher
    b>Ehrlichia chaffeensis is one of the causative agents of canine ehrlichiosis and human monocytic ehrlichiosis (HME). Canine ehrlichiosis caused by E...
  84. Sexton D, Corey G, Carpenter C, Kong L, Gandhi T, Breitschwerdt E, et al. Dual infection with Ehrlichia chaffeensis and a spotted fever group rickettsia: a case report. Emerg Infect Dis. 1998;4:311-6 pubmed
    ..to be endemic in North Carolina; cases of human ehrlichial infection were recognized there soon after Ehrlichia chaffeensis was recognized as an important cause of tick-borne disease in the southeastern United States...