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In Europe, Lyme borreliosis is caused by Borrelia burgdorferi sensu stricto, B. afzelii, B. garinii and the recently described species B. spielmanii. For the development of diagnostic tools, the heterogeneity of the causative agents must be considered. The serological diagnosis should follow the principle of a two-step procedure: a sensitive enzyme-linked immunosorbent analysis as the first step, followed by immunoblot (IgM and IgG) if reactive. The sensitivity and standardization of immunoblots have been enhanced by the use of recombinant antigens instead of whole cell lysates. Improved sensitivity has resulted from the use of recombinant proteins primarily expressed in vivo (e.g. VlsE) and the combination of homologous proteins from different strains (e.g. DbpA). At present, detection rates for serum antibodies are 20–50% in localized, 70–90% in disseminated early and nearly 100% in late disease. Detection of the borreliae by culture or PCR should be confined to specific indications. The best results are obtained from skin biopsies (50–70% with culture or PCR) and synovial tissue or fluid (50–70% with PCR). Cerebrospinal fluid is positive in only 10–30%. Methods that are not recommended for diagnostic purposes include antigen tests in body fluids, PCR of urine and lymphocyte transformation tests. [ABSTRACT FROM AUTHOR]

Describes the disease entity Lyme borreliosis. Nature of Lyme borreliosis; Clinical manifestations; Etiologic agent of the disease; Disease transmission; Incidence of the disease; Microbiology of Borrelia burgdorferi; Pathogenesis; Diagnostic procedures.

Borrelia burgdorferi sensu lato is the causative agent of Lyme disease (LD), an infectious disease occurring in North America, Europe, and Asia in different clinical stages. B. burgdorferi sensu lato encompasses at least 12 species, with B. burgdorferi sensu stricto, B. garinii, and B. afzelii being of highest clinical importance. Immunologic testing for LD as well as recent vaccination strategies exclusively refer to proteinaceous antigens. However, B. burgdorferi sensu stricto exhibits glycolipid antigens, includ- ing 6-O-acylated cholesteryl β-D-galactopyranoside (ACGa1), and first the data indicated that this compound may act as an immunogen. Here we investigated whether B. garinhi and B. afzelii also possess this antigen, and whether antibodies directed against these compounds are abundant among patients suffering from different stages of LD. Gas-liquid chromatography/mass spectroscopy and NMR spectroscopy showed that both B. garinii and B. afzelii exhibit ACGa1 in high quantities. In contrast, B. hermsii causing relapsing fever features 6-O-acylated cholesteryl β-D-glucopyranoside (ACG1c). Sera derived from patients diagnosed for LD contained antibodies against ACGa1, with 80% of patients suffering from late stage disease exhibiting this feature. Antibodies reacted with ACGa1 from all three B. burgdorferi species tested, but not with ACG1c from B. hermsii. These data show that ACGa1 is present in all clinically important B. burgdorferi species, and that specific antibodies against this compound are frequently found during LD. ACGaI may thus be an interesting tool for improving diagnostics as well as for novel vaccination strategies. [ABSTRACT FROM AUTHOR]

belongs to human pathogenic species within the sensu lato complex in Europe, which is a causative agent of Lyme disease. So far, the human disease caused by B. spielmanii has been associated with skin manifestations. The aim of the study was to analyze 4 human B. spielmanii isolates by pulsed-field gel electrophoresis and to localize genes of 3 important Borrelia proteins: OspA, DbpA, and VlsE. The analysis revealed variation within linear plasmid profiles among the strains; isolate PSigII contained a large plasmid of 100 kb compared with a 50 kb plasmid present in the 3 other B. spielmanii isolates, all carried the genes ospA and dbpA. Differences in the size of linear plasmids among the Borrelia strains may be a result of host-pathogen interactions, as the PSigII strain was the only strain of the 4 tested strains to be isolated from a patient with a previous history of Lyme disease, whereas 3 other patients were diagnosed with this disease for the first time. [ABSTRACT FROM AUTHOR]

Abstract: To study pathogenic mechanisms of Lyme meningoradiculitis, dorsal root ganglia (DRG) cells and two neuronal cell lines (B50, SH-SY5Y) were incubated with Borrelia garinii, the Borrelia species most frequently isolated from CSF of Lyme neuroborreliosis patients in Europe. We demonstrated that (I) OspA-positive B. garinii adhere to neuronal cells, (II) Borrelia adhesion can be blocked by a monoclonal antibody against OspA, (III) preincubation with proteoglycans interferes with the adhesion process and (IV) rOspA directly binds to the proteoglycans. This indicates that both OspA and the cell bound proteoglycans are involved in the attachment of B. garinii to neuronal cells. [Copyright &y& Elsevier]

Borrelia burgdorferi may cause an acute infection of the central nervous system (CNS) that rarely leads to chronic disease. To characterize host immunity to B. burgdorferi in humans, we performed serial T cell receptor (TCR) variable β (TCRBV) chain analyses in blood and cerebrospinal fluid (CSF) samples from 10 patients with acute neuroborreliosis. In most patients, we found significant differences in TCRBV expression between CSF and peripheral blood T cells, predominantly involving CD8[sup +] T cells. T cells that accumulated in the CSF had a memory phenotype and expressed high levels of C-C chemokine receptor 5 and CD69. Serial studies demonstrated that CD8[sup +] T cell accumulation decreased continuously after resolution of the infection. In 2 patients, serial analysis of the TCR-α and -β chain sequences revealed that overexpression of TCRBV in CSF was caused by extensive clonal expansion of CD8[sup +] T cells. Our findings support the role of CD8[sup +] T cells during the early host defense against spirochete infection of the CNS. [ABSTRACT FROM AUTHOR]

We describe the isolation and characterization of Rickettsia monacensis sp. nov. (type strain, IrR/Munich[sup T]) from an Ixodes ricinus tick collected in a city park, the English Garden in Munich, Germany. Rickettsiae were propagated in vitro with Ixodes scapularis cell line ISE6. BLAST analysis of the 16S rRNA, the citrate synthase, and the partial 190-kDa rickettsial outer membrane protein A (rOmpA) gene sequences demonstrated that the isolate was a spotted fever group (SFG) rickettsia closely related to several yet-to-be-cultivated rickettsiae associated with I. ricinus. Phylogenetic analysis of partial rompA sequences demonstrated that the isolate was genotypically different from other validated species of SFG rickettsiae. R. monacensis also replicated in cell lines derived from the ticks I. ricinus (IREII) and Dermacentor andersoni (DAE100) and in the mammalian cell lines L-929 and Veto, causing cell lysis. Transmission electron microscopy of infected ISE6 and Veto cells showed rickettsiae within the cytoplasm, pseudopodia, nuclei, and vacuoles. Hamsters inoculated with R. monacensis had immunoglobulin G antibody titers as high as 1:16,384, as determined by indirect immunofluorescence assay. Western blot analyses demonstrated that the hamster sera cross-reacted with peptides from other phylogenetically distinct rickettsiae, including rOmpA. R. monacensis induced actin tails in both tick and mammalian cells similar to those reported for R. rickettsii. R. monacensis joins a growing list of SFG rickettsiae that colonize ticks but whose infectivity and pathogenicity for vertebrates are unknown. [ABSTRACT FROM AUTHOR]

A total of 305 Ixodes ricinus ticks (243 nymphs and 62 adults) were collected from three different regions of Thuringia in Middle Germany which are known to be endemic for Borrelia burgdorferi. Our aim was to investigate the carrier rate of ticks for granulocytic Ehrlichia species. The presence of ehrlichial 16S ribosomal DNA was investigated by polymerase chain reaction. Using primers specific for the Ehrlichia phagocytophila group PCR fragments of 151 bp and 943 bp, respectively, were produced in positive samples. Adult ticks showed a significantly higher infection rate (4/62; 6.5%) compared to nymphs (3/243; 1.2%). Prevalence rates varied between 0 and 3.8% regarding the different areas under investigation. The nucleotide sequences showed high similarity (between 97.5% and 99% identity) to the known sequences of the three E. phagocytophila group members HGE agent, E. phagocytophila and Ehrlichia equi. The sequence data did not allow a final classification to a particular member of this group. [Copyright &y& Elsevier]

The human granulocytic ehrlichiosis agent (HGEa) survives extreme differences between ticks and humans, possibly by use of differential expression of specific antigens for survival in different hosts. The role of the immunodominant p44 antigens is unknown. In this study, HGEa cultured in human or tick cells was probed with human, mouse, and hamster serum and with monoclonal antibodies (MAbs). p44 antigens were strongly expressed in human HL-60 cells but were strikingly reduced in tick cells. In HGEa alternately grown in HL-60 or tick cells, a p44 epitope recognized by MAb R5E4 was expressed in human but not tick cells. This was not a temperature effect, because incubation of infected tick cells at 37 C didnot induce expression of the p44 epitope. The p44 antigen predominates in human but not tick cells and may be involved in regulatory changes that mediate survival of the HGEa by immune modulation after tick transmission. [ABSTRACT FROM AUTHOR]