Sensitive and specific serodiagnosis of Lyme disease by enzyme-linked immunosorbent assay with a peptide based on an immunodominant conserved region of Borrelia burgdorferi vlsE

VlsE, the variable surface antigen of Borrelia burgdorferi, contains an immunodominant conserved region named IR(6). In the present study, the diagnostic performance of a peptide enzyme-linked immunosorbent assay (ELISA) based on a 26-mer synthetic peptide (C(6)) with the IR(6) sequence was explored. Sensitivity was assessed with serum samples (n = 210) collected from patients with clinically defined Lyme disease at the acute (early localized or early disseminated disease), convalescent, or late disease phase. The sensitivities for acute-, convalescent-, and late-phase specimens were 74% (29 of 39), 85 to 90% (34 of 40 to 35 of 39), and 100% (59 of 59), respectively. Serum specimens from early neuroborreliosis patients were 95% positive (19 of 20), and those from an additional group of patients with posttreatment Lyme disease syndrome yielded a sensitivity of 62% (8 of 13). To assess the specificity of the peptide ELISA, 77 serum samples from patients with other spirochetal or chronic infections, autoimmune diseases, or neurologic diseases and 99 serum specimens from hospitalized patients in an area where Lyme disease is not endemic were examined. Only two potential false positives from the hospitalized patients were found, and the overall specificity was 99% (174 of 176). Precision, which was assessed with a panel of positive and negative serum specimens arranged in blinded duplicates, was 100%. Four serum samples with very high anti-OspA antibody titers obtained from four monkeys given the OspA vaccine did not react with the C(6) peptide. This simple, sensitive, specific, and precise ELISA may contribute to alleviate some of the remaining problems in Lyme disease serodiagnosis. Because of its synthetic peptide base, it will be inexpensive to manufacture. It also will be applicable to serum specimens from OspA-vaccinated subjects.     

Improved immunoglobulin M serodiagnosis in Lyme borreliosis by using a mu-capture enzyme-linked immunosorbent assay with biotinylated Borrelia burgdorferi flagella.

A mu-capture enzyme-linked immunosorbent assay (ELISA) for detection of serum immunoglobulin M (IgM) antibodies to Borrelia burgdorferi by using biotinylated purified B. burgdorferi flagella was developed. The diagnostic performance of the mu-capture ELISA was compared with that of a conventional indirect ELISA. Sera from untreated patients with erythema migrans (n = 50), neuroborreliosis (n = 100), and acrodermatitis chronica atrophicans (ACA; n = 48) were investigated. The cutoff of the ELISAs was adjusted to a diagnostic specificity of 98% on the basis of examination of 200 serum specimens from healthy controls. The mu-capture ELISA increased the diagnostic sensitivity in patients with erythema migrans from 32 to 48% (P less than 0.01) and in patients with neuroborreliosis from 37 to 57% (P less than 0.001). Because of an increased signal/noise ratio, the mu-capture ELISA yielded a significantly better quantitative discrimination of individual positive measurements from the cutoff (P less than 0.001). The increased signal/noise ratio was most likely a consequence of the elimination of IgG competition for the test antigen. This may also explain why 12% of patients with ACA showed significantly increased specific IgM levels only by the mu-capture ELISA. Of patients with ACA, 27% had IgM rheumatoid factor. The mu-capture principle with a directly labeled antigen showed no interference with IgM rheumatoid factor, in contrast to the indirect ELISA. The high diagnostic performance and ease of this three-step mu-capture ELISA make it suitable for routine anti-B. burgdorferi IgM serodiagnosis.     

Establishment of enzyme-linked immunosorbent assay using purified recombinant 83-kilodalton antigen of Borrelia burgdorferi sensu stricto and Borrelia afzelii for serodiagnosis of Lyme disease.

The 83-kDa antigen of Borrelia burgdorferi was expressed as a recombinant protein in Escherichia coli and purified for use in an enzyme-linked immunosorbent assay (p83-ELISA). Antibodies to the 83-kDa antigen of both the immunoglobulin G (IgG) and IgM isotypes could be detected in all stages of Lyme disease. Sensitivity varied, depending on the clinical stage of illness. In early stages, as defined for 118 patients with erythema migrans, it was found to be 20% (24 of 118 patients: 7 with IgM, 16 with IgG, and 1 with IgM and IgG). Of the patients with late-stage Lyme arthritis and acrodermatitis chronica atrophicans, 94% (16 of 17:2 with IgM and IgG and 14 with IgG) and 86% (36 of 42:2 with IgG and IgM and 34 with IgG) revealed positive results in the p83-ELISA, respectively. p83 displays sequence heterogeneity according to the genomospecies, but when the reactions of serum specimens from acrodermatitis chronica atrophicans patients and arthritis patients with p83 derived from representative strains of B. burgdorferi sensu stricto and Borrelia afzelii in ELISAs were compared, no differences in specificity and sensitivity were seen. When 82 serum specimens from healthy controls were tested, none had IgG and only 3 (4%) had IgM antibodies, indicating a high specificity. Positive reactions with antibodies against Treponema pallidum (1 of 37 patients; IgG) and Epstein-Barr virus (1 of 44 patients; IgM) and with autoantibodies of various specificities (1 of 53 patients; IgG) were seen with < 3% of the serum samples te11111111111111111111 high speficicity for B. burgdorferi.2+ 13% for IgM antibodies, the IgM p83-ELISA provided little diagnostic information for Lyme disease, whereas the IgG p83-ELISA appears to be a suita ;e test for serodiagnosis of advanced-stage Lyme disease.     

Epitope mapping of the immunodominant invariable region of Borrelia burgdorferi VlsE in three host species

VlsE, the variable surface antigen of Borrelia burgdorferi, contains a 26-amino-acid-long immunodominant invariable region, IR(6). In the present study, three overlapping 14-mer peptides reproducing the sequence of IR(6) were used as peptide-based enzyme-linked immunosorbent assay antigens to map this invariable region in infected monkeys, mice, and human Lyme disease patients. Antibodies of the two primate species appeared to recognize IR(6) as a single antigenic determinant, while mouse antibodies recognized multiple epitopes within this region.     

Comparative reactivity of human sera to recombinant VlsE and other Borrelia burgdorferi antigens in class-specific enzyme-linked immunosorbent assays for Lyme borreliosis

A comparative study of human sera was conducted to determine which purified preparations of 11 recombinant antigens of Borrelia burgdorferi sensu stricto were diagnostically most important in enzyme-linked immunosorbent assays (ELISAs). To assess sensitivity, 20 serum samples obtained 1-6 weeks after onset of illness from 20 persons who had physician-diagnosed erythema migrans (EM) were tested for IgM and IgG antibodies. In tests for IgM antibody, seropositivity of > or = 25% was recorded when ELISAs had separate preparations of protein (p) 37, p41-G, outer-surface protein (Osp) C, OspE, OspF or VlsE antigens. Sera reacted most frequently (80% positive) with VlsE antigen in analyses for IgG antibodies. When results of both class-specific assays were considered for VlsE, OspC or OspF, 90% of the EM cases were serologically confirmed. Results of specificity testing with a further 59 sera from persons who had syphilis, louse-borne relapsing fever, oral infections, rheumatoid arthritis or human granulocytic ehrlichiosis and 28 normal sera indicated no false positive reactions when VlsE antigen was used in tests for IgM antibody. One of the 11 louse-borne relapsing fever sera cross-reacted with VlsE antigen in tests for IgG antibodies. Minor cross-reactivity also occurred when p37, OspC, OspE or OspF antigens were used. Overall, VlsE was the most suitable antigen for laboratory diagnosis of Lyme borreliosis during the early weeks of B. burgdorferi infection because of its high sensitivity and specificity.     

Lyme disease assay which detects killed Borrelia burgdorferi.

We developed an in vitro assay showing that Borrelia burgdorferi organisms were killed by serum from patients with Lyme disease. Twenty of 20 Lyme disease serum samples caused B. burgdorferi killing in a range of 36 to 99% compared with the mean number of viable spirochetes when sera from 10 healthy individuals were used. The percentage of killing of B. burgdorferi increased with convalescent serum from patients with early Lyme disease. The borreliacidal activity was detectable in some sera diluted 640-fold and was abrogated after treatment with anti-human immunoglobulin G. In contrast, pooled or individual normal human serum did not cause a decrease in the number of viable B. burgdorferi. Borreliacidal activity was also not detected in sera from patients with relapsing fever, rocky mountain spotted fever, syphilis, mononucleosis, rheumatoid factor, or DNA antibodies. Our results show that borreliacidal activity can be used as a specific serodiagnostic test for detecting Lyme disease.     

Significantly improved accuracy of diagnosis of early Lyme disease by peptide enzyme-linked immunosorbent assay based on the borreliacidal antibody epitope of Borrelia burgdorferi OspC

Highly specific borreliacidal antibodies are induced by infection with Borrelia burgdorferi, and the immunodominant response during early Lyme disease is specific for an epitope within the 7 amino acids nearest the C terminus of OspC. We evaluated the ability of an enzyme-linked immunosorbent assay (ELISA) based on a synthetic peptide (OspC7) that matched the region to detect the response and compared the sensitivity during early Lyme disease to that for an FDA-approved Western blot. When the optical density value was adjusted to 98% specificity based on the results from testing normal or uncharacterized sera (n = 236) or sera from patients with blood factors or illnesses that commonly produce antibodies that cross-react with B. burgdorferi antigens (n = 77), 115 (73%) of 157 sera from patients likely to have early Lyme disease were positive for immunoglobulin M (IgM) antibodies and 17 (11%) also had IgG antibodies. In addition, the IgM ELISA reactivities and the titers of antibodies detected by a flow cytometric borreliacidal antibody test correlated closely (r = 0.646). Moreover, the IgM ELISA was significantly more sensitive (P < 0.001) than the Western blot procedure. The findings therefore confirmed that the peptide IgM ELISA detected OspC borreliacidal antibodies and provided strong evidence that the test can eliminate the necessity for confirming early Lyme disease by a supplementary test such as Western blotting.     

Borrelia burgdorferi VlsE antigen for the serological diagnosis of Lyme borreliosis

In this study, raising and development of antibody response to Borrelia burgdorferi infection in 66 Italian patients suffering from culture-confirmed Lyme borreliosis erythema migrans (EM) was investigated. Sixty-two of 66 cultures obtained from biopsies were identified as B. afzelii by PCR. A total of 175 serially collected serum samples were tested by using two different sets of commercial assays: Enzygnost Lyme link VlsE/IgG and Enzygnost Borreliosis IgM (DADE Behring, Marburg, Germany) and LIAISON Borrelia IgG and IgM (Diasorin, Saluggia, Italy). Considering only samples obtained at first presentation when EM was clinically evident, 49/66 patients (72.4%) were IgG or IgM positive by Enzygnost, whereas 33/66 (50.0%) patients were IgG or IgM positive by LIAISON. Taking into account the follow-up period, eight patients sero-converted for IgG or IgM by Enzygnost and four by LIAISON. Similar and very good specificity values were obtained by all methods. Testing sera obtained from blood donors (n = 300) and from patients suffering from some of the most common biological conditions possibly resulting in false-positive reactivity in Lyme disease serology (n = 100) showed that Enzygnost Lyme link VlsE/IgG was the more specific (98.3%), followed by LIAISON Borrelia IgG (96.5%), and considering IgM tests, Enzygnost Borreliosis IgM showed to be 95.3%% specific, whereas the LIAISON Borrelia IgM was 92.8% specific. Recombinant VlsE antigens obtained from all three B.burgdorferi genospecies pathogenic to humans (included in Enzygnost Lyme link VlsE/IgG) greatly improved serodiagnosis of Lyme disease.     

Western immunoblot and flagellum enzyme-linked immunosorbent assay for serodiagnosis of Lyme borreliosis.

Western immunoblot with a whole-cell lysate was compared with an enzyme-linked immunosorbent assay with a purified flagellum antigen of Borrelia burgdorferi for serodiagnosis of Lyme borreliosis. The assays showed similar sensitivities and specificities in detecting immunoglobulin M and/or immunoglobulin G antibodies in sera from 68 patients with neuroborreliosis and 44 controls with meningitis and encephalitis or with multiple sclerosis. Flagellum enzyme-linked immunosorbent assay is more easily standardized and seems to be a more suitable diagnostic test in a routine laboratory.     

Detection of Borrelia burgdorferi in urine of Peromyscus leucopus by inhibition enzyme-linked immunosorbent assay.

An inhibition enzyme-linked immunosorbent assay was developed to detect Borrelia burgdorferi, the etiologic agent of Lyme borreliosis, in urine from white-footed mice (Peromyscus leucopus). Of the 87 urine specimens tested from 87 mice collected in widely separated tick-infested sites in Connecticut, 57 (65.5%) contained detectable concentrations of spirochetal antigens. Forty-seven (62.7%) of 75 serum samples analyzed contained antibodies to B. burgdorferi. In culture work with tissues from bladders, kidneys, spleens, or ears, 50 of 87 mice (57.5%) were infected with B. burgdorferi. Thirty-eight (76%) of 50 infected mice had antigens of this spirochete in urine, while 36 (72%) individuals had infected bladders. Of those with infected bladders, 24 (66.7%) mice excreted subunits or whole cells of B. burgdorferi into urine. Successful culturing of B. burgdorferi from mouse tissues, the presence of serum antibodies to this bacterium, and detection of antigens to this spirochete in urine provide further evidence that multiple assays can be performed to verify the presence of B. burgdorferi in P. leucopus.     

Development of enzyme-linked immunosorbent assays using recombinant borrelial antigens for serodiagnosis of Borrelia burgdorferi infection

  To improve IgG antibody detection in the serodiagnosis of Borrelia burgdorferi infection, indirect enzyme-linked immunosorbent assays (ELISAs) were developed utilizing purified recombinant antigens of B. burgdorferi sensu lato: the chromosomally encoded proteins p100 of strain PKo (B. afzelii) and p4li (internal flagellin fragments) derived from strains PKo, PBi (B. garinii), and B31 (B. burgdorferi sensu stricto). In Western blot analysis, these proteins have proved to be highly specific and sensitive for IgG antibody detection, especially in late manifestations of Lyme borreliosis. Sera from 464 forest workers, a high-risk group for infections with B. burgdorferi, were investigated and the results compared with those obtained by a commercial ELISA using an octyl-β-d-glucopyranoside (OGP) extract from B. afzelii (PKo) cells as the antigenic substrate. Sera derived from 200 blood donors served for determination of the 95% specific cut-off level. The number of positive test results using OGP-ELISA (23.9%) was only slightly higher than that using p100-ELISA (19.8%); corresponding results were observed in 84.7% of all sera (14.2% positive, 70.5% negative). The frequency and interassay correspondence of positive results increased with the age of the forest workers, as most markedly demonstrated by p100 and OGP assays (P<0.0001). Using the p41i-ELISAs, generally no significant strain-dependent differences in sensitivity were found (PKo, 13.8%; PBi, 14.2%; B31, 12.9%). Compared with the p100-ELISA, the p41i-assays showed significantly lower detection rates for IgG antibodies (P<0.03) and a reduced capacity for quantitative discrimination between seropositive individuals and negative controls (P<0.0007). At a 95% specificity, the IgG antibody detection rate could be increased to 23.1% when the p100-ELISA was evaluated in combination with the assays using p41i/PBi and P41i/B31. Due to its high sensitivity, the specific recombinant p100-ELISA might be a suitable test for detection of late immune responses to B. burgdorferi, thus being especially useful for epidemiological investigations. Received: 7 March 1996     

Measurement of antibodies to the Borrelia burgdorferi flagellum improves serodiagnosis in Lyme disease.

The isolation of Borrelia burgdorferi flagella and an enzyme-linked immunosorbent assay (ELISA) for detection of immunoglobulin G (IgG) and IgM to the B. burgdorferi flagellum are described. The diagnostic performance of the flagellum ELISA for serodiagnosis of Lyme disease was compared with the performance of a traditional whole cell B. burgdorferi sonic extract ELISA. We examined sera and cerebrospinal fluid (CSF) from 56 patients with lymphocytic meningoradiculitis (Bannwarth's syndrome), the most frequent secondary-stage manifestation of Lyme disease in Europe. Two hundred healthy individuals and patients with aseptic meningitis, encephalitis, Guillain-Barré syndrome, and syphilis served as controls. The flagellum ELISA was significantly more sensitive than the sonic extract ELISA. The diagnostic sensitivities were increased from 41.1 to 76.8% (P less than 0.01) for IgG and from 35.7 to 67.9% (P less than 0.05) for IgM detection in serum. The increase in sensitivity was most pronounced in patients with a short duration of disease (less than 20 days after onset). The diagnostic specificity increased for IgG detection but was almost unaltered for IgM. The flagellum ELISA did not improve the diagnostic sensitivity of measuring antibodies to borreliae in CSF, most likely owing to the low level of unspecific antibodies in CSF compared with serum. The cross-reactivity of sera and CSF from patients with syphilis decreased significantly. The flagellum antigen of B. burgdorferi shows no strain variation, is easy to purify in sufficient quantity, and is therefore a suitable reference antigen for routine serodiagnosis of Lyme disease.     

Borrelia burgdorferi enzyme-linked immunosorbent assay for discrimination of OspA vaccination from spirochete infection.

Recombinant Lyme disease vaccines based on purified preparations of outer surface protein A (OspA) have been shown to be effective in preventing transmission of Borrelia burgdorferi in experimental animal models and are now being tested in humans. Since the most widely used screening tests for Lyme disease are based on a whole-cell sonicate of B. burgdorferi, serologic false positivity in vaccinated persons could result from reactivity to OspA within the antigen preparation. In order to avoid serologic false positivity in vaccinated subjects, we developed an immunoassay based on a low-passage-number, naturally occurring variant of B. burgdorferi which lacks the plasmid encoding OspA and OspB. The use of an antigen preparation derived from this organism provided sensitive and specific detection of B. burgdorferi seropositivity in experimental animals and in human Lyme disease cases. The OspA-B-negative enzyme-linked immunosorbent assay (ELISA) also appeared to be capable of discriminating the vaccinated state from vaccine failure and natural infection in experimental animals. Sera from human subjects participating in a vaccine trial gave false-positive results with an ELISA based on an OspA-containing strain, but no such reactivity was observed when the OspA-negative ELISA was used. We conclude that low-passage-number OspA-B-negative isolates in immunoassays may become useful for the immunologic discrimination of the vaccinated state, natural infection, and vaccine failure.     

Use of recombinant OspC from Borrelia burgdorferi for serodiagnosis of early Lyme disease.

Infection with Borrelia burgdorferi, the etiologic agent of Lyme disease, is associated with an early and dominant humoral response to the spirochete's 23-kDa outer surface protein C (OspC). We have cloned and expressed OspC as a fusion protein in Escherichia coli and have shown that patient serum samples react with it in an enzyme-linked immunosorbent assay (ELISA) (S. J. Padula, A. Sampieri, F. Dias, A. Szczepanski, and R. W. Ryan, Infect. Immun. 61:5097-5105, 1993). Now we have compared the detection of B. burgdorferi-specific immunoglobulin M antibodies in 74 individuals with culture-positive erythema migrans by a whole-cell ELISA, immunoblot, and the recombinant OspC (rOspC) ELISA. Seventy-six negative controls were also studied. With all of the tests, there was a statistically significant association between the duration of disease and the frequency of a positive result. With the rOspC ELISA, the predictive value of a positive test was 100% and the predictive value of a negative test was 74%. Similar results were obtained with the whole-cell ELISA and with the immunoblot using as the source of test antigen a strain of B. burgdorferi which expresses abundant levels of OspC. We conclude that the use of rOspC in an ELISA is a convenient, readily automated, and easily standardized test for the serodiagnosis of early Lyme disease.     

Serodiagnosis of erythema migrans and acrodermatitis chronica atrophicans by the Borrelia burgdorferi flagellum enzyme-linked immunosorbent assay.

The diagnostic performance of an enzyme-linked immunosorbent assay (ELISA) using purified Borrelia burgdorferi flagella as test antigen was compared with that of a B. burgdorferi sonic extract ELISA. We tested sera from 200 healthy controls, 107 patients with erythema migrans (EM), 50 patients with acrodermatitis chronica atrophicans (ACA), and 98 patients with various dermatological disorders without clinical evidence of active Lyme borreliosis. The flagellum ELISA was significantly more sensitive than the sonic extract ELISA. With sera from patients with EM, the diagnostic sensitivity for immunoglobulin G (IgG) antibody detection increased from 11.2 to 35.5% (P less than 0.001) and for IgM antibody detection it increased from 16.6 to 44.8% (P less than 0.001). In the flagellum ELISA, the number of positive tests increased significantly (P less than 0.005) when the duration of EM exceeded 1 month, but still only about 50% of patients with longstanding (1 to 12 months) untreated EM were IgG seropositive. Concomitant general symptoms did not affect the antibody level, whereas patients with multiple erythema were more frequently seropositive. All sera from patients with EM which were positive in the sonic extract ELISA were also positive in the flagellum ELISA. Not only did the overall number of positive tests increase, but the flagellum ELISA yielded a significantly better quantitative discrimination between seropositive patients and controls (P less than 0.002). IgG antibodies to the B. burgdorferi flagellum were found in all sera from patients with ACA, indicating persistence of an antiflagellum immune response in late stages of Lyme borreliosis. IgM reactivity in sera from patients with ACA was shown to be unspecific and the result IgM rheumatoid factor. A rheumatoid factor was detected in sera from 32% of patients with ACA, compared with 7.5% of patients with EM. The improved diagnostic performance, the ease of standardization of the flagellum antigen, and the lack of strain variation make the B. burgdorferi flagellum a needed reference antigen for growing routine serology in Lyme borreliosis.     

C-terminal invariable domain of VlsE may not serve as target for protective immune response against Borrelia burgdorferi

VlsE, the variable surface antigen of the Lyme disease spirochete, Borrelia burgdorferi, contains two invariable domains, at the amino and carboxyl termini, respectively, which collectively account for approximately one-half of the entire molecule's length and remain unchanged during antigenic variation. It is not known if these two invariable domains are exposed at the surface of either the antigen or the spirochete. If they are exposed at the spirochete's surface, they may elicit a protective immune response against B. burgdorferi and serve as vaccine candidates. In this study, a 51-mer synthetic peptide that reproduced the entire sequence of the C-terminal invariable domain of VlsE was conjugated to the carrier keyhole limpet hemocyanin and used to immunize mice. Generated mouse antibody was able to immunoprecipitate native VlsE extracted from cultured B. burgdorferi B31 spirochetes, indicating that the C-terminal invariable domain was exposed at the antigen's surface. However, this domain was inaccessible to antibody binding at the surface of cultured intact spirochetes, as demonstrated by both an immunofluorescence experiment and an in vitro killing assay. Mouse antibody to the C-terminal invariable domain was not able to confer protection against B. burgdorferi infection, indicating that this domain was unlikely exposed at the spirochete's surface in vivo. We concluded that the C-terminal invariable domain was exposed at the antigen's surface but not at the surface of either cultured or in vivo spirochetes and thus cannot elicit protection against B. burgdorferi infection.     

Efficacy of enzyme-linked immunosorbent assay in serodiagnosis of aspergillosis.

Sera from 43 cases of aspergillosis, 73 cases of other bronchopulmonary diseases, and 50 healthy persons were examined for the presence of antibodies to Aspergillus fumigatus. Enzyme-linked immunosorbent assay proved to be more efficacious than the immunodiffusion test and counterimmunoelectrophoresis in the cases of allergic bronchopulmonary and invasive aspergillosis.     

Lyme disease and Borrelia burgdorferi infections in Europe

Lyme disease is endemic in Europe. The strains of the causative agent, Borrelia burgdorferi, seem to be antigenically more heterogeneous than the North American isolates. The only documented vector for this bacterium in Europe is ixodes ricinus, but other vectors might be involved as observed in the United States. The tick hosts are not yet well documented in Europe. Human infection occurs principally during summer months. The clinical aspect of the disease has particular features in Europe: at the early stage of the disease, a single and large erythema chronicum migrans is observed on the skin; complications often include meningoradiculonevritis (Bannwarth's syndrome) and later, acrodermatitis chronica atrophians; arthritis is less frequent in Europe than in the USA. The culture of B. burgdorferi from the lesions is difficult. The diagnosis of the disease is performed on the basis of serological tests: immunofluorescence assay where the important thing is to define a cutoff titer; ELISA tests using either whole cells or supernatant of sonicated cells or flagellar antigen; passive haemagglutination for IgG; IgM solid phase haemadsorption; Western blot (immunoblot) seems interesting to perform on a research basis to determine to which protein antigens patients are responding with antibody. Once antibody production begins, it is usually in the form of IgM antibody to flagellin protein (41 kD), with time, both IgM and IgG antibodies to a variety of other antigens appear. Prophylaxis is based on health services and public education because a prompt removal of the tick diminishes risk of infection with B. burgdorferi (4 p. cent of cases after tick bite). The treatment includes aminopenicillins or tetracyclines at the early stage. The second and third stages of borreliosis are treated by high doses aminopenicillins or cetriaxone.     

Analysis of antibody response to invariable regions of VlsE, the variable surface antigen of Borrelia burgdorferi

VlsE, the variable surface antigen of Borrelia burgdorferi, consists of two invariable domains at the amino and carboxyl termini and one central variable domain. The latter contains six invariable regions, IR(1) to IR(6), and six variable regions. In the present study, the antigenicity of all of the invariable regions in B. burgdorferi-infected monkeys, humans, and mice was assessed by peptide-based enzyme-linked immunosorbent assays. Only one invariable region, IR(6), was antigenic in all animals of the three host species. IR(2) and IR(4) were also antigenic in mice.     

Serologic analysis of white-tailed deer sera for antibodies to Borrelia burgdorferi by enzyme-linked immunosorbent assay and western immunoblotting.

White-tailed deer serum samples were collected in the Minneapolis-St. Paul, Minn., metropolitan area during the fall and winter months from 1989 to 1992 and analyzed for antibodies to Borrelia burgdorferi, the etiologic agent of Lyme borreliosis. Ninety-eight percent of the serum samples were collected from regions where currently the vector tick, Ixodes dammini, is nonexistent. Antibodies to B. burgdorferi were detected in 2.2% of 508 samples by enzyme-linked immunosorbent assay, and their presence was confirmed by Western immunoblot analysis. Western immunoblotting yielded mean numbers of reactive bands of 0.1 and 6.0 for samples that were negative and positive for antibodies by enzyme-linked immunosorbent assay, respectively. The molecular weights of the antigens in many of the reactive bands from positive samples were similar to the molecular weights of antigens reactive with samples from humans with Lyme borreliosis. An antibody response to the major outer surface proteins A and B was not detected. Serologic analysis of deer sera may provide a valuable method for surveillance programs designed to monitor the spread of B. burgdorferi in nature.