Ehrlichia chaffeensis, TRP32, TRP47, and TRP120, have been identified and molecularly characterized withinE. chaffeensis 200-kDa ankyrin protein (Ank200) and the minor immunodeterminants in the N- and C-terminal regions of chaffeensis 20-mer, 20-mer, and 21-mer, respectively) in terminal acidic domains, which reacted with antibodies in sera from human monocytotropic ehrlichiosis (HME) patients and an epitope-containing regions were identified in the N terminus and the C terminus of TRP47. The sensitivities and specificities of synthetic peptides representing these and other well-defined major immunodeterminants of E.TRP47. Major antibody epitopes of Ank200 were localized to four polypeptide regions (18-mer,E. chaffeensis-infected dog. Two minor E. chaffeensis serum samples that had detectable assay (IFA) were tested. All 31 serum samples reacted with at least one (96.8%) with TRP120 peptides, 27 (87.1%) with TRP32 peptides, 24 (77.4%) with TRP47 peptides, 19 (61.3%) with Ank200 peptides, and 28 (90.3%) with recombinant TRP120-TR protein. A mixture of the two most sensitive peptides from TRP120 and TRP32 did not provide enhanced analytical sensitivity compared to that provided by TRP120 alone. Our results demonstrate that the TRP120 peptide can be utilized for development of standardized sensitive point-of-care and reference laboratory immunodiagnostics for HME. This is the first study to compare analysis of molecularly defined major antibody epitopes with IFA for diagnosis of HME. were determined by enzyme-linked immunosorbent assay (ELISA). Thirty-one HME patientE. chaffeensis antibodies (titers from 64 to 8,192) by indirect fluorescentantibodyE. chaffeensis peptide, 30
Recently, major species-specific antibody epitopes in three immunoreactive tandem repeat proteins (TRPs) of tandem repeat (TR) regions. In this study, we mapped the major immunodeterminants of the