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Ilkka Seppälä

Publications and source records attributed to Ilkka Seppälä.

12 recordsLinked to original sources
PubMed2006

Antigenicity of borrelial protein BBK32 fragments in early Lyme borreliosis.

Recombinantly produced borrelial BBK32 protein fragments originating from Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii were evaluated as antigens in the serology of Lyme borreliosis (LB). In ELISA, a mid-portion hydrophilic fragment reacted with LB patient sera. Of the 23 patients with culture- or PCR-positive erythema migrans (EM), 43 % at diagnosis and 52 % at convalescence were positive for at least one Borrelia species-specific variant BBK32 fragment antigen. In parallel ELISAs with BBK32 whole proteins from the three borrelial subspecies as antigens, 17 % at diagnosis and 26 % at convalescence were positive. These results suggest that BBK32 protein fragments may improve the early IgG serology of LB compared to the BBK32 whole protein.

Antibodies, Bacterial↗
PubMed2005

New antigens for serologic diagnosis of neuroborreliosis in children.

OBJECTIVE: To evaluate serology with novel Borrelia-specific protein or peptide antigens in the laboratory diagnosis of neuroborreliosis (NB) in children. METHODS: The performance of enzyme-linked immunosorbent assays with several recombinant borrelial protein antigens and invariable region 6 synthetic peptide antigen and of a commercial enzyme-linked immunosorbent assay with the flagella antigen were evaluated in the serodiagnosis and follow-up of children with clinical suspicion of NB. Serum samples were obtained from 20 children with neurologic symptoms indicative of NB. The patients were retrospectively divided into 2 groups based on the laboratory tests at presentation indicating definite (n = 7) or probable (n = 13) NB. RESULTS: In addition to cerebrospinal fluid (CSF) lymphocytic pleocytosis and CSF antiflagella antibodies, all 7 patients with definite NB had serum IgG antibodies to at least 2 of the 3 novel antigens at presentation. The 13 patients with probable NB had variable laboratory findings: CSF pleocytosis (n = 7), CSF antiflagella IgM antibodies (n = 4), serum antiflagella IgM and/or IgG antibodies (n = 10). Of these 13 patients, 7 had serum IgG antibodies to 2 of the 3 novel antigens at presentation. During long term follow-up, serum anti-invariable region 6 antibodies disappeared. CONCLUSIONS: The present study suggests that assessment of serum antibodies to a panel of Borrelia-specific antigens could improve the laboratory diagnosis of NB at presentation.

Adolescent↗
PubMed2003

Recombinant or peptide antigens in the serology of Lyme arthritis in children.

The performance of ELISAs with the recombinant antigens decorin-binding protein A (DbpA), DbpB, and BBK32 (from Borrelia afzelii, B. garinii, and B. burgdorferi sensu stricto) and VlsE peptide antigen invariable region 6 (IR(6)) were evaluated in the serodiagnosis and follow-up of children with Lyme arthritis (LA). Serum samples were obtained from 52 children with clinically typical and serologically confirmed LA. In IgG ELISAs, at diagnosis, 50 samples were positive for BBK32, 51 for DbpA, 40 for DbpB, and 51 for IR(6). In the posttreatment follow-up, the rate of decline of the antibodies to the recombinant protein antigens or to IR(6) did not appear useful in the prediction of the treatment response or the clinical course of LA. Yet, IR(6) seems to have the greatest potential to be used universally in the diagnostic serology of Lyme borreliosis (LB). Alternate to that, the use of several specific borrelial antigens, in parallel, might improve the accuracy of serology for LB.

Adolescent↗
PubMed2003

Diagnosis of Lyme neuroborreliosis with antibodies to recombinant proteins DbpA, BBK32, and OspC, and VlsE IR6 peptide.

Three recombinant antigens, decorin binding protein A (DbpA), BBK32, and outer surface protein C (OspC), and IR(6) peptide of borrelial VlsE protein, were evaluated for the diagnosis of neuroborreliosis (NB), using cerebrospinal fluid (CSF) and serum samples from 89 patients. Their performances in enzyme-linked immunosorbent assay (ELISA) were compared with that of commercial flagella antigen. IgG ELISAs were performed with three variants of each recombinant antigen originating from Borrelia burgdorferi sensu stricto, B. afzelii and B. garinii, and with the IR(6) peptide. IgM antibodies were analysed against OspC and flagella. Of the patients whose CSF contained elevated anti-flagella IgG antibodies, 93% were positive for at least three of the new antigens. Of those with negative or borderline CSF anti-flagella antibodies, 51% were positive for three new antigens. Antibodies to BBK32 were detectable mainly in early disease. Antibodies to DbpA and IR(6) were observed in early and late NB. The use of the new antigens at presentation of the disease improved the laboratory diagnosis of NB. In IgG ELISAs, the diagnostic sensitivity of assays with the new antigens was between 75 and 88%, but was only 52% with the flagella antigen. The discriminatory power between patient and control samples appeared better in the CSF than in the serum. We suggest that assessment of CSF antibodies to at least two antigens, using either flagella and one of the new antigens or two of the new antigens, would improve the current diagnostic yield of NB.

Adhesins, Bacterial↗
PubMed2003

Varicella zoster and Borrelia burgdorferi are the main agents associated with facial paresis, especially in children.

BACKGROUND: The etiology of facial paresis (FP) often remains unresolved. Yet, a microbial association is frequently suspected. OBJECTIVE: To evaluate the infectious etiology of FP by using sensitive tests. STUDY DESIGN: We studied the serum and cerebrospinal fluid of 42 patients diagnosed with idiopathic peripheral facial paresis using sensitive serological methods and nucleic acid detection and for reference, 42 patients with other neurological disorders (OND) matched for age, sex, season and geographical area. RESULTS: Varicella zoster virus and Borrelia burgdorferi accounted for 56% of all associated agents in children with FP compared with 11% of OND (P=0.01). In adults, the respective numbers were 29 and 13%. Other treatable etiological agents, Chlamydia pneumoniae and Mycoplasma pneumoniae, accounted for 11% in children and 8% in adults and with the same prevalence between patients with FP and OND. CONCLUSIONS: Microbes, with specific therapy available accounted for 52% of all associated agents in the patients with FP when compared with 26% in controls with OND (P=0.04). Based on this, we conclude that the patients with FP may benefit from antimicrobial therapy.

Adolescent↗
PubMed2002

Complement inhibitor factor H binding to Lyme disease spirochetes is mediated by inducible expression of multiple plasmid-encoded outer surface protein E paralogs.

Borrelia burgdorferi spirochetes can circumvent the vertebrate host's immune system for long periods of time. B. burgdorferi sensu stricto and B. afzelii, but not B. garinii, bind the complement inhibitor factor H to protect themselves against complement-mediated opsonophagocytosis and killing. We found that factor H binding and complement resistance are due to inducible expression of a wide repertoire of outer surface protein E (OspE) lipoproteins variably called OspE, p21, ErpA, and ErpP. Individual Borrelia strains carry multiple plasmid-encoded OspE paralogs. Together the OspE homologs were found to constitute an array of proteins that bind factor H via multiple C-terminal domains that are exposed outwards from the Borrelial surface. Charged residue substitutions in the key binding regions account for variations between OspE family members in the optimal binding pH, temperature, and ionic strength. This may help the spirochetes to adapt into various host environments. Our finding that multiple plasmid-encoded OspE proteins act as virulence factors of Borrelia can provide new tools for the prevention and treatment of borreliosis.

Amino Acid Sequence↗
PubMed2002

Cloning of the gene encoding the decorin-binding protein B (DbpB) in Borrelia burgdorferi sensu lato and characterisation of the antibody responses to DbpB in Lyme borreliosis.

A genome walking technique was applied to borrelial DNA to clone the gene encoding decorin-binding protein B (DbpB) in Borrelia garinii and B. afzelii. Sequence analysis showed 62-67% identity of the predicted amino acid sequences of DbpB between the B. afzelii and B. garinii strains and B. burgdorferi sensu stricto. Within subspecies, the sequences were 99-100% identical. The respective recombinant DbpBs (rDbpBs) were produced and tested as antigens in an enzyme-linked immunosorbent assay (ELISA) for Lyme borreliosis (LB). In IgG ELISA, with rDbpBs as antigens, 11 (73%) of 15 adult patients with Lyme arthritis and 9 (64%) of 14 with neuroborreliosis were positive. Of children with Lyme arthritis, 40 (77%) of 52 were positive. All adult and paediatric patients with disseminated LB had high titres of anti-flagellin IgG antibodies. Seropositivity against rDbpB from B. garinii predominated, 39 (65%) of 60 of the positive samples reacting with rDbpB from B. garinii. In patients with erythema migrans, IgM antibodies to rDbpB were detected in 1 (4%) of 23 and IgG antibodies in 6 (26%) of 23. These results indicate that DbpB may be a useful antigen in the IgG serology for disseminated LB. The high inter-species sequence heterogeneity observed indicates that a combination of the variant DbpBs should be included in the antigen set to cover all the relevant borrelial subspecies in the serodiagnosis of LB.

Adhesins, Bacterial↗
PubMed2002

Recombinant OspC from Borrelia burgdorferi sensu stricto, B. afzelii and B. garinii in the serodiagnosis of Lyme borreliosis.

Genes for the outer-surface protein C (OspC) from three north European human isolates of Borrelia burgdorferi sensu stricto, B. afzelii and B. garinii were cloned and sequenced. Polyhistidine-tagged recombinant OspC (rOspC) proteins were produced in Escherichia coli and used, after biotinylation, as antigens on streptavidin-coated plates in enzyme-linked immunosorbent assays (ELISA). In IgM ELISA, 30% (5/17) and 35% (6/17) of patients with erythema migrans (EM) in the acute or convalescent phase, respectively, reacted with one to three rOspCs. Of the patients, 53% (8/15) with neuroborreliosis (NB) and 53% (8/15) with Lyme arthritis (LA) had IgM antibodies to OspC. The immunoreactivity was stronger against rOspC from B. afzelii and B. garinii than against rOspC from B. burgdorferi sensu stricto. In early Lyme borreliosis (LB), rOspC and flagella performed equally well in detecting IgM antibodies. Cross-reactive antibodies to rOspC were observed in serum samples from patients with rheumatoid factor positivity and with syphilis or Epstein-Barr virus (EBV) infection. In IgM ELISA, thiocyanate in the serum dilution buffer reduced EBV-associated non-specific positive reactions. Of the patient sera examined in IgG ELISA, 30% (5/17) with EM in the acute phase, 35% (6/17) with EM in the convalescent phase, 33% (5/15) with NB and 60% (9/15) with LA were positive. Because of the heterogeneity of OspC, a polyvalent antigen with several OspC variants from at least B. afzelii and B. garinii is needed to improve the sensitivity of OspC ELISA in the serodiagnosis of LB in Europe.

Amino Acid Sequence↗
PubMed2002

Species-specific serodiagnosis of Lyme arthritis and neuroborreliosis due to Borrelia burgdorferi sensu stricto, B. afzelii, and B. garinii by using decorin binding protein A.

The antigenic potential of decorin binding protein A (DbpA) was evaluated in serodiagnosis of human Lyme borreliosis (LB). The dbpA was cloned and sequenced from the three pathogenic Borrelia species common in Europe. Sequence analysis revealed high interspecies heterogeneity. The identity of the predicted amino acid sequences was 43 to 62% among Borrelia burgdorferi sensu stricto, B. afzelii, and B. garinii. The respective recombinant DbpAs (rDbpAs) were produced and tested as antigens by Western blotting and enzyme-linked immunosorbent assay (ELISA). One hundred percent of patients with neuroborreliosis (NB) and 93% of patients with Lyme arthritis (LA) reacted positively. Sera from the majority of patients reacted with one rDbpA only and had no or low cross-reactivity to other two variant proteins. In patients with culture-positive erythema migrans (EM), the sensitivity of rDbpA immunoglobulin G (IgG) or IgM ELISA was low. The DbpA seems to be a sensitive and specific antigen for the serodiagnosis of LA or NB, but not of EM, provided that variants from all three pathogenic borrelial species are included in the combined set of antigens.

Adhesins, Bacterial↗
PubMed2002

Recombinant BBK32 protein in serodiagnosis of early and late Lyme borreliosis.

Borrelial protein BBK32 was evaluated as an antigen in the serodiagnosis of early and disseminated Lyme borreliosis (LB). bbk32 was cloned and sequenced from eight isolates of the three pathogenic Borrelia species. The identities between the amino acid sequences of the BBK32 proteins from Borrelia burgdorferi sensu stricto, B. garinii, and B. afzelii isolates were 71 to 100%. By immunoglobulin G (IgG) Western blotting (WB) or enzyme-linked immunosorbent assay (ELISA), up to 74 and 100% of acute- and convalescent-phase samples, respectively, from 23 patients with erythema migrans (EM) were positive for recombinant BBK32 protein from B. afzelii. In the serology of disseminated LB, the three variant BBK32 antigens cross-reacted. In total, 14 of 14 samples from patients with neuroborreliosis and 15 of 15 samples from patients with Lyme arthritis were positive. The specificities of the IgG ELISA with the variant BBK32 antigens for EM and disseminated borreliosis were 81 to 92% and 89 to 95%, respectively. Our findings indicate that the BBK32 proteins are promising serodiagnostic antigens for the detection of early and disseminated LB but that variant BBK32 proteins may be needed either in parallel or in combination with an immunoassay for LB to cover all the relevant borrelial species that cause the disease.

Antibodies, Bacterial↗
PubMedDate not supplied

Lyme borreliosis and facial paralysis--a prospective analysis of risk factors and outcome.

PURPOSE: To evaluate the incidence of Lyme borreliosis in patients with acute idiopathic facial paralysis with special emphasis on the risk factors that explain the poor outcome of facial paralysis and occurrence of Lyme borreliosis. MATERIALS AND METHODS: During a 2-year period, we prospectively studied 503 consecutive patients with acute idiopathic facial paralysis for the presence of Lyme borreliosis. We screened the patients for antibodies to Borrelia burgdorferi and for symptoms or signs related to Lyme borreliosis. Chi-square and logistic regression tests were used for the statistical analysis. Special attention was paid to strict criteria for the diagnosis of Lyme borreliosis. RESULTS: Eleven (2.2%) of the 503 patients with facial paralysis had Lyme borreliosis. Fever, headache, pharyngalgia, enlarged cervical lymph nodes, bilateral paralysis, and arthralgia were more common in patients with Lyme borreliosis than in those without it. In the logistic regression modeling the best combination of explanatory variables for predicting the occurrence of Lyme borreliosis included summer season at the onset of facial paralysis, presence of enlarged cervical lymph nodes, and arthralgia. The best combination of explanatory variables to predict the poor outcome of facial paralysis was total paralysis of facial nerves, recurrent facial paralysis, and hyperacusis. CONCLUSIONS: Lyme borreliosis is an important infectious cause of facial paralysis. In our study, 11 of 503 patients with acute idiopathic facial paralysis had Lyme borreliosis. The screening for serum antibodies in addition to the thorough evaluation of the history of the patient and of the patient's clinical signs or symptoms possibly linked with Lyme borreliosis, are essential when diagnosing Lyme borreliosis.

Acute Disease↗