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L A Magnarelli

Publications and source records attributed to L A Magnarelli.

At least 91 records · Page 5Linked to original sources
PubMed1988

Enzyme-linked immunosorbent assays for the detection of class-specific immunoglobulins to Borrelia burgdorferi.

Enzyme-linked immunosorbent assays were developed to detect immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies to Borrelia burgdorferi, the etiologic agent of Lyme disease. Of the 135 blood samples obtained during 1985-1986 from persons in Connecticut with erythema migrans or other clinical manifestations of this spirochetosis, 106 (79%) contained IgM antibody. In separate tests for IgG antibody, 106 (83%) of 128 specimens were considered positive. To assess the specificity of these assays, the authors analyzed sera from patients with other spirochetal infections or nonrelated diseases. Heterologous IgM antibody was detected in 32 (42%) of 77 samples, while cross-reactivity occurred in 17 (25%) of 69 sera screened for IgG antibody. Geometric mean titers for homologous reactions were usually twofold or more higher than those of heterologous reactions. Information on IgG antibody is particularly useful for serodiagnosis, but because of the cross-reactivity among Borrelia and Treponema, clinical data and the use of other serologic tests may be needed to separate Lyme disease from other spirochetal infections.

Antibodies, Bacterial↗
PubMed1988

Serologic diagnosis of Lyme disease.

Indirect fluorescent antibody tests and enzyme-linked immunosorbent assays are being used as laboratory aids for the diagnosis of Lyme disease and related disorders. Depending on the needs, polyvalent or class-specific reagents can be used to detect total immunoglobulins (Ig) or IgM and IgG antibodies. The sensitivities of these assays are relatively low when serum samples are obtained from patients within 3 weeks after onset of erythema migrans and are tested by either the IFA method or ELISA. During neuritis or arthritis, IgG antibody levels are usually elevated, and serologic verification is more easily achieved. Cross-reactivity occurs when sera from patients with Lyme disease, relapsing fever, or treponemal infections are screened against heterologous antigens, but these diseases can usually be separated clinically or by further seroanalyses. Although IFA tests and ELISA are both suitable for confirming Lyme disease, the objective results and the ability to perform many more analyses make ELISA the preferred method.

Antibodies, Bacterial↗
PubMed1988

New Borrelia burgdorferi antigenic variant isolated from Ixodes dammini from upstate New York.

A previously undescribed Borrelia burgdorferi antigenic variant was isolated from each of four Ixodes dammini larvae removed from white-footed mice, Peromyscus leucopus, captured in Millbrook, N.Y. This site is in the northern range of the known distribution of the tick in the northeastern United States. The molecular weights of approximately 32,500 and 35,500 for outer surface A and outer surface B proteins, respectively, were distinctly higher than those for previously characterized isolates from North American ticks, humans, and wild mammals. A prominent low-molecular-weight protein of about 23,500 was also present. All four isolates infected Syrian hamsters and retained their antigenicity after passage through these rodent hosts. Serum samples from patients with Lyme disease tended to have immunoglobulin M, immunoglobulin G, and immunoglobulin antibodies to Connecticut B. burgdorferi 2591 at titers slightly higher than or equal to those recorded for an antigenically different strain of B. burgdorferi from Millbrook, N.Y.

Animals↗
PubMed1988

Serologic analyses of Peromyscus leucopus, a rodent reservoir for Borrelia burgdorferi, in northeastern United States.

An enzyme-linked immunosorbent assay (ELISA) and indirect fluorescent-antibody test were used to detect antibodies to Borrelia burgdorferi, the causative agent of Lyme disease, in Peromyscus leucopus (white-footed mouse). Of the 661 mice captured in Connecticut, Rhode Island, and New York during 1980 and 1983 to 1987, 166 (25.1%) had antibodies to B. burgdorferi by ELISA. Comparative analyses of 210 serum specimens, collected in areas where Lyme disease is endemic, revealed a threefold difference in sensitivity between the ELISA (38.1% positive) and the indirect fluorescent-antibody method (12.4%). Although prevalence of seropositive P. leucopus was highest during June, elevated amounts of antibody (1:1,280 to 1:2,560) were detected in mice that harbored spirochetes during all seasons. Being reservoirs for B. burgdorferi, these rodents are suitable for monitoring spirochete infections at foci and should be included in field evaluations of control programs aimed at suppressing Lyme disease.

Animals↗
PubMed1988

Ticks and biting insects infected with the etiologic agent of Lyme disease, Borrelia burgdorferi.

Members of 18 species of ticks, mosquitoes, horse flies, and deer flies were collected in southeastern Connecticut and tested by indirect fluorescent-antibody staining methods for Borrelia burgdorferi, the etiologic agent of Lyme disease. An infection rate of 36.2% (116 tested), recorded for immature Ixodes dammini, exceeded positivity values for all other arthropod species. Prevalence of infection for hematophagous insects ranged from 2.9% of 105 Hybomitra lasiophthalma to 14.3% of seven Hybomitra epistates. Infected I. dammini larvae and nymphs coexisted with infected Dermacentor variabilis (American dog tick) immatures on white-footed mice (Peromyscus leucopus), but unlike I. dammini, none of the 55 adult American dog ticks collected from vegetation harbored B. burgdorferi. Groups of 113 field-collected mosquitoes of Aedes canadensis and 43 Aedes stimulans were placed in cages with uninfected Syrian hamsters. Of these, 11 females of both species contained B. burgdorferi and had fed fully or partially from the hamsters. No spirochetes were isolated from the hamsters, but antibodies were produced in one test animal.

Aedes↗
PubMed1988

Borreliosis in equids in northeastern United States.

During 1982 and 1985, blood samples from 705 equids were examined for antibodies to Borrelia burgdorferi. By indirect immunofluorescence staining, IgM and total immunoglobulin (IgM and IgG) antibodies were detected in 37 (5.3%) and 90 (12.8%) serum specimens, respectively. The geometric mean titer for IgM antibody (140.4) was highest during July, whereas total immunoglobulin ranged from 94.1 in October to 338 in May. Eighty-six equids with total immunoglobulin to B burgdorferi lived in areas of Connecticut where the primary tick vector, Ixodes dammini, was present. Of the 86 equids, 9 from Lyme, Connecticut and Westchester County, New York had antibodies to B burgdorferi and developed limb or joint disorders that resulted in single or recurrent episodes of lameness.

Animals↗
PubMed1987

Clinical and serologic studies of canine borreliosis.

During 1984 and 1985, blood samples were obtained from 271 dogs that were suspected of having borreliosis. The dogs lived in areas known to be infested with ticks and had been examined because of limb/joint disorders or for unknown illnesses marked by fever, anorexia, or fatigue. Lameness had been the most frequently reported clinical manifestation. Analyses of serum specimens, by an indirect fluorescent antibody (IFA) method or by an ELISA, detected antibodies to Borrelia burgdorferi, the etiologic agent of borreliosis in dogs and of Lyme disease in human beings. Antibody to B burgdorferi was detected in 76.3% of 114 specimens from dogs living in the lower Hudson Valley region of New York State (predominantly Westchester County), in 66.5% of 155 specimens from dogs from southern Connecticut, and in single specimens from dogs from Rhode Island and California. Geometric mean antibody titers peaked during the winter. Results of IFA tests and ELISA were in agreement, but the latter method yielded less variable results, had greater sensitivity, and was more easily standardized. Five dogs from New York State and Connecticut seropositive to B burgdorferi had developed kidney disorders during or after episodes of intermittent lameness. Application of murine monoclonal antibody in an IFA procedure verified the presence of B burgdorferi in renal cortical tissues from one dog.

Animals↗
PubMed1987

Early detection and persistence of antibodies to Borrelia burgdorferi in persons with Lyme disease.

An indirect immunofluorescence antibody (IFA) test and an enzyme-linked immunosorbent assay (ELISA) were used during 1984 to detect total immunoglobulins (Ig) or IgM and IgG antibodies to Borrelia burgdorferi. Of the 139 serum samples tested by IFA, representing 110 persons with erythema chronicum migrans (ECM), 84 (60%) had either or both class-specific immunoglobulins. Serologic confirmation was made for 64 (58%) patients; serum specimens from 54 (49%) of these had elevated levels of IgM antibodies. These immunoglobulins were usually present within 14 days after diagnosis of ECM and persisted for at least 30 days. Significant titers of IgG antibodies were recorded for 54 serum samples and remained elevated for at least 19 weeks after ECM was first observed. When utilizing polyvalent (Ig) conjugates, ELISA procedures verified antibody presence in 80 of the 84 serum samples positive by IFA. Similarly, samples negative in IFA tests were non-reactive by ELISA. Additional tests of 40 control samples, obtained from persons without Lyme disease, were also uniformly negative. Both methods were suitable for confirmation of Lyme disease infections.

Antibodies, Bacterial↗
PubMed1987

Lyme disease in Canada with possible transmission by an insect.

The first documented case of Lyme disease to have originated in Canada is presented. A 51-year old French female nurse visited Quebec, Canada from 20 July to 5 August, 1984 and contracted Lyme disease. She reported an insect bite on 3 August 1984 on the back of her knee with erythema chronicum migrans appearing at the site of the bite on 5 August 1984. The patient presented with meningeal lymphocytic reaction near the end of September, 1984. Total Ig serum titers in indirect immunofluorescence tests on 1 October 1984, 10 October 1984, and 10 January 1985 were 1/512, 1/2048 and 1/16,384, respectively.

Animals↗
PubMed1987

Cross-reactivity in serological tests for Lyme disease and other spirochetal infections.

Serum specimens from 163 persons with Lyme disease, tick-borne or louse-borne relapsing fever, yaws, syphilis, leptospirosis, or Rocky Mountain spotted fever were analyzed to assess the specificity of indirect fluorescent antibody (IFA) tests, an enzyme-linked immunosorbent assay (ELISA), and microscopic agglutination (MA) procedures. Strong cross-reactivity occurred when sera from individuals with Lyme disease, tick-borne relapsing fever, and louse-borne relapsing fever were tested against heterologous Borrelia antigens. Antibodies to Borrelia burgdorferi bound to Treponema pallidum in immunofluorescence tests for syphilis. Sera from subjects with syphilis cross-reacted in IFA tests and the ELISA for Lyme disease. Immunoglobulin antibodies to Borrelia or Treponema spirochetes, however, did not react with serovars of Leptospira interrogans in MA or IFA tests, and the prevalence of false-positive results in the reciprocal analyses was negligible.

Antibodies, Bacterial↗
PubMed1987

Prevalence of Borrelia burgdorferi and Babesia microti in mice on islands inhabited by white-tailed deer.

Borrelia burgdorferi and Babesia microti were isolated from 35 of 51 white-footed mice (Peromyscus leucopus) and meadow voles (Microtus pennsylvanicus) captured on two Narragansett Bay, R.I., islands inhabited by deer, the principal host for the adult stages of the vector tick, Ixodes dammini. Immature ticks parasitized mice from both islands. From 105 mice captured on four other islands not inhabited by deer neither pathogen was isolated, nor were I. dammini found.

Animals↗
PubMed1987

New infectious spirochete isolated from short-tailed shrews and white-footed mice.

A spirochete with two periplasmic flagella was isolated from the blood or tissues of spleens and kidneys from short-tailed shrews (Blarina brevicauda) and white-footed mice (Peromyscus leucopus) in Connecticut and Minnesota. After inoculation, the shrew-mouse spirochete infected Swiss mice and Syrian hamsters. This spirochete is morphologically and serologically distinct from the species of Treponema, Borrelia, Leptospira, and Spirochaeta examined.

Animals↗
PubMed1987

Prevalence of Borrelia burgdorferi in white-footed mice and Ixodes dammini at Fort McCoy, Wis.

Borrelia burgdorferi, the causative agent of Lyme disease, was isolated from 15 of 17 white-footed mice (Peromyscus leucopus) and 54 of 82 subadult Ixodes dammini from Fort McCoy, Wis. Of the 47 isolates tested, all reacted in indirect fluorescent-antibody tests with monoclonal antibodies directed against a surface protein of B. burgdorferi (approximate molecular weight, 31,000) and flagellins that are common to all Borrelia species. Indirect fluorescent-antibody reactions were variable when an antibody that binds to a surface protein with an approximate molecular weight of 34,000 was tested. The major proteins of isolates from ticks and mice had approximate molecular weights of 31,000, 34,000, and 41,000. Antibodies to B. burgdorferi were present (titer, greater than or equal to 1:64) in 16 of 97 white-tailed deer (Odocoileus virginianus). The mean number of subadult I. dammini on mice captured in June 1986 was 6.5, and the mean number of adult I. dammini on deer killed in November 1986 was 5.9. The presence of ticks and the high prevalence of I. dammini and mice infected with B. burgdorferi establish that Fort McCoy is an area in which the Lyme disease agent is highly endemic, even though there have been relatively few documented cases in humans. The low number of reported cases in humans may be a result of National Guard and reserve unit personnel returning home to civilian life and having symptoms expressed subsequently, or it could be due to misdiagnosis or nonreporting.

Animals↗
PubMed1987

Seasonal prevalence of Borrelia burgdorferi in natural populations of white-footed mice, Peromyscus leucopus.

Borrelia burgdorferi, the etiologic agent of Lyme disease, was isolated from 111 of 237 Peromyscus leucopus captured during all seasons of the year. Borreliae were cultured from tissues of the spleen (101 mice), left kidney (76 mice), and right kidney (73 mice), from blood (12 mice), and from one fetus. Mice were infected during the winter, when immature Ixodes dammini were inactive. The prevalence of infection during the winter (less than or equal to 33%) was more than twofold lower than that during the summer (ca. 75%), a time when nymphal ticks are abundant. Overwintering, infected mice are reservoir hosts for subadult ticks that begin feeding in early spring. Twenty white-footed mice from which B. burgdorferi was isolated from tissues of spleen or kidney but not from blood were parasitized by larval I. dammini or Dermacentor variabilis which harbored borreliae. We conclude that these mice were infectious to feeding ticks, even though borreliae were not isolated from blood.

Animals↗