Cerebrospinal fluid chemokine CXCL13 in the diagnosis of neuroborreliosis in children.

BACKGROUND: The diagnosis of Lyme neuroborreliosis (LNB) requires laboratory confirmation because neurological symptoms indicative of LNB are not specific. Recent studies have suggested that a chemokine, CXCL13, could have an important role in the diagnosis of LNB. The aim of this study was to assess CXCL13 levels in the cerebrospinal fluid (CSF) of children with LNB. METHODS: CSF samples were available for 57 children with symptoms indicative of LNB. Based on the presence of anti-flagella antibodies and pleocytosis in CSF, patients were divided into 3 different groups: confirmed LNB (n = 24), possible LNB (n = 16), and non-LNB (n = 17). CXCL13 levels were determined with a commercial kit (Quantikine). RESULTS: All 24 patients with confirmed LNB had elevated CXCL13 levels in CSF. Elevated CXCL13 was also observed in the majority of patients without anti-flagella antibodies in the CSF (possible LNB). Of the 17 non-LNB and 50 control samples, 1 was positive. CONCLUSIONS: In LNB, the production of CXCL13 in CSF seems to precede antibody production. Assessment of CSF CXCL13 may improve the diagnostics for children with possible LNB.

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 to decorin-binding protein B (DbpB) in the diagnosis of Lyme neuroborreliosis in children.

BACKGROUND: Laboratory support is needed to confirm the clinical diagnosis of Lyme neuroborreliosis (LNB). Antibodies to Borrelia-specific proteins have been used to improve serological diagnostics. The aims of this study were to assess the occurrence of antibodies to decorin-binding protein B (DbpB) in serum and cerebrospinal fluid (CSF) in children with LNB and to evaluate the performance of DbpB variants in the diagnosis of LNB in children. METHODS: Serum and CSF sample pairs were available from 57 children evaluated for LNB. Based on the presence of anti-flagella antibodies and pleocytosis in the CSF, patients were divided into three different groups: confirmed LNB (n=24), possible LNB (n=16), and non LNB (n=17). Recombinant DbpBs from three Borrelia burgdorferi sensu lato species - Borrelia burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii - were used in an ELISA to detect IgG antibodies. RESULTS: The sensitivity of variant recombinant DbpBs in serum and CSF samples varied between 0% and 46% and between 0% and 42%, respectively. In CSF, the most sensitive antigen was the DbpB variant from B. garinii. CONCLUSIONS: Serum or CSF antibodies to DbpB do not appear to be beneficial in the laboratory diagnosis of LNB in children.

Antibodies to recombinant decorin-binding proteins A and B in the cerebrospinal fluid of patients with Lyme neuroborreliosis.

Cerebrospinal fluid (CSF) and serum samples from 34 patients with proven neuroborreliosis (NB) and 22 patients with suspected neuroborreliosis (SNB) from Finland were analysed for antibodies to decorin-binding proteins A (DbpA) and B (DbpB). Antibodies to recombinant protein antigens originating from Borrelia burgdorferi sensu stricto, B. afzelii, or B. garinii species were studied by enzyme-linked immunosorbent assay (ELISA). Of the 34 patients with NB, 100% of the CSF and 88% of the serum samples had IgG antibodies to 1 to 3 variants of DbpA and 79% of the CSF and 70% of the serum samples were positive for 1 to 3 DbpB variants. Antibodies to DbpB seemed to be associated with lymphocytic pleocytosis in the CSF and short duration of the disease, whereas antibodies to DbpA in the CSF were observed irrespective of the duration of the disease and lymphocytic pleocytosis. Among the variant antigens, CSF reactivity was mainly with the DbpB from B. garinii, whereas positivity with the DbpA from B. afzelii or B. garinii predominated. The results suggest that CSF antibodies to DbpB might be useful as a marker of active infection whereas antibodies to DbpA seem to persist a long time after acute phases of NB.

Immune responses to borrelial VlsE IR6 peptide variants.

Laboratory confirmation of Lyme borreliosis (LB) relies mainly on the demonstration of anti-borrelial antibodies. In recent studies, a novel VlsE protein IR(6) peptide-based assay has been introduced. Our aim was to evaluate the IR(6) peptides from three Borrelia burgdorferi sensu lato genospecies in the serodiagnosis of European and North American patients. Five VlsE protein IR(6) peptide variants representing sequences from B. burgdorferi sensu stricto, B. garinii, and B. afzelii were used as antigens in both IgG and IgM enzyme-linked immunosorbent assays (ELISA). Serum antibodies of 187 patients at different stages of LB from Europe and the United States were evaluated for serodiagnosis. For comparison samples were tested with one of the commercial IR(6) ELISAs. Three B. afzelii IR(6) variant peptides revealed antibodies that were concordant with each other. B. burgdorferi sensu stricto peptide antibodies mostly paralleled B. afzelii peptide antibodies, and positive values were also obtained in the majority of European sera. For several sera, B. garinii IR(6) peptide antibodies were discordant to B. afzelii peptide antibodies. The commercial IR(6) peptide antibody assay (C6 ELISA) results correlated better with B. burgdorferi sensu stricto IR(6) than with B. garinii IR(6) peptide IgG results, especially in sera from patients with facial palsy. Thus, antibody specificity to IR(6) peptides may vary according to the infecting Borrelia species. In some manifestations of the disease, C6 ELISA may not cover all LB cases. Evidently, the methodological aspects in ELISA design for peptide antibody measurements are important as well as the amino acids sequence of the antigen.

Subtly impaired humoral immunity predisposes to frequently recurring genital herpes simplex virus type 2 infection and herpetic neuralgia.

BACKGROUND: Immunogenetic factors predisposing to recurrent genital herpes remain poorly characterized. METHODS: In a prospective case-control study, 52 consecutive patients with frequently recurring outbreaks of genital herpes were compared with 80 herpes simplex virus (HSV)-seropositive (types 1 and 2) and 70 HSV-seronegative control subjects. Immunoglobulins (Igs), type-specific anti-HSV-2 IgG and IgG subclass antibodies against glycoprotein G, levels of C3 and C4, and classical pathway hemolytic complement activity were measured, and IgG1 and IgG3 allotyping; C4 immunophenotyping; C4* real-time polymerase chain reaction (PCR) genotyping; and HLA-A*, B*, and DR* typing were performed. RESULTS: The G3m(g),G1m(a/a(x)) haplotype was more frequent in patients than in HSV-seronegative control subjects (P=.047). Compared with all control subjects, low levels of total IgG1 (odds ratio [OR], 4.9 [95% confidence interval {CI}, 2.0-12.5]; P=.001) and IgG3 (OR 3.6 [95% CI 1.7-7.8]; P=.001), but not of anti-HSV-2 antibodies, were associated with recurrences. Levels of complement were lowest in patients. The C4* null type was negatively associated with neuralgia (OR, 0.2 [95% CI, 0.06-0.81]; P=.022). CONCLUSIONS: Low levels of antibody-dependent cellular cytotoxicity-mediating IgG1 and IgG3 antibodies, partly dependent of allotype, may predispose to recurrent genital herpes. Antibodies produced by T helper type 1 responses, potentially against an unknown epitope, appear to be relevant in recurrences. In patients, C4* deficiencies are associated with protection from herpetic neuralgias, possibly through reduced inflammation.

Serum IgG2 concentration is associated with Gm-allotypes of IgG2 but not with the R131H polymorphism of human Fc-gamma receptor type IIa.

Serum concentrations of immunoglobulins IgG, IgG1, and IgG2 were determined in 62 Finnish subjects who were also typed for Gm(n) allele of IgG2 and R131 and H131 alleles of the Fcy receptor IIa. Statistically significant G2m-allotype-associated differences in serum concentrations of IgG2 were found; the mean concentration of IgG2 was high in Gm(n)-positive homozygotes (3.9 g/liter) and low in Gm(n)-negative individuals (2.6 g/liter; P = 0.0036), which is in accordance with previous reports. Contrary to an earlier report, no statistically significant R131/ H131-allotype-associated differences were found in serum concentrations of IgG2, not even in the case where the IgG2 concentration was calculated relative to the IgGI or IgG concentration (IgG2/IgG1 or IgG2/IgG). The gene frequencies of R131 and H131 alleles were 0.516 and 0.484, respectively, which did not differ significantly from those reported earlier for Finnish or other Caucasian populations.