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1.
MMW Fortschr Med ; 148(25): 30-2, 2006 Jun 22.
Artigo em Alemão | MEDLINE | ID: mdl-16859157

RESUMO

As a rule, the tick, Ixodes ricinus, is picked up when its victim walks through low vegetation and brushes it off a leaf or blade of grass. Often hours later, the tick scores the skin at the site it selects and then pushes its barbed hypostome into the tiny wound to anchor itself to its victim with the aid of a cement-like substance and the barbs. While it sucks up blood, Borrelia burgdorferi spirochetes pass out of the tick's intestine into its salivary glands and thence into the host. It is therefore of decisive importance that the tick be removed with a special forceps as early as possible. The use of such substances as glue, alcohol or nail varnish to remove the tick must be discouraged. Currently, antibiotic prophylaxis, examination of the tick for the presence of B. burgdorferi, or serological follow-up tests are not recommended.


Assuntos
Mordeduras e Picadas , Borrelia burgdorferi , Doença de Lyme/diagnóstico , Carrapatos , Animais , Mordeduras e Picadas/diagnóstico , Borrelia burgdorferi/isolamento & purificação , Diagnóstico Diferencial , Feminino , Humanos , Doença de Lyme/microbiologia , Masculino , Carrapatos/microbiologia , Carrapatos/fisiologia , Fatores de Tempo
2.
MMW Fortschr Med ; 148(25): 39-41, 2006 Jun 22.
Artigo em Alemão | MEDLINE | ID: mdl-16859159

RESUMO

Every manifestation of Lyme borreliosis needs to be treated with antibiotics. The type of antibiotic applied and duration of treatment will depend on the stage and severity of the disease. Erythema migrans, Borrelia lymphocytoma, Lyme arthritis and acrodermatitis chronica atrophicans are primarily treated orally. If neurological symptoms, severe Lyme carditis or eye manifestations are present, intravenous treatment is initially recommended. For oral therapy, doxycycline, amoxicillin, cefuroxime and, if intolerance is shown, azithromycin, are available. For intravenous treatment ceftriaxone, cefotaxime or penicillin G is employed. The overall prognosis for treated Lyme borreliosis is good. However, in particular when manifestations with substantial organic injury have persisted, incomplete healing must be expected. With the exception of erythema migrans, every manifestation should be subjected to a careful diagnostic work-up prior to the start of treatment, because premature antibiotic administration is not only associated with an elevated risk for the patient, but can also mask important diagnostic signs.


Assuntos
Antibacterianos/uso terapêutico , Borrelia burgdorferi , Doença de Lyme/tratamento farmacológico , Acrodermatite/tratamento farmacológico , Acrodermatite/etiologia , Administração Oral , Antibacterianos/administração & dosagem , Doença Crônica , Ensaios Clínicos como Assunto , Eritema Migrans Crônico/diagnóstico , Eritema Migrans Crônico/tratamento farmacológico , Humanos , Injeções Intravenosas , Doença de Lyme/complicações , Doença de Lyme/diagnóstico , Neuroborreliose de Lyme/tratamento farmacológico , Prognóstico , Estudos Prospectivos , Pseudolinfoma/tratamento farmacológico , Estudos Retrospectivos , Fatores de Tempo
3.
Neurology ; 65(3): 448-50, 2005 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-16087912

RESUMO

Using protein expression profiling, the authors identified an upregulation of the chemokine B lymphocyte chemoattractant (BLC) in the CSF of patients with neuroborreliosis but not in patients with noninflammatory and various other inflammatory neurologic diseases. This upregulation was confirmed by ELISA, showing increased BLC levels in every neuroborreliosis patient while being undetectable in patients with noninflammatory neurologic diseases. These results point to BLC as a putative additional diagnostic marker for neuroborreliosis.


Assuntos
Líquido Cefalorraquidiano/imunologia , Quimiocinas CXC/líquido cefalorraquidiano , Neuroborreliose de Lyme/líquido cefalorraquidiano , Neuroborreliose de Lyme/diagnóstico , Adolescente , Adulto , Idoso , Anticorpos/análise , Linfócitos B/imunologia , Biomarcadores/líquido cefalorraquidiano , Líquido Cefalorraquidiano/química , Quimiocina CXCL13 , Quimiocinas CXC/imunologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Encefalite/líquido cefalorraquidiano , Encefalite/diagnóstico , Encefalite/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Neuroborreliose de Lyme/imunologia , Ativação Linfocitária/imunologia , Meningite/líquido cefalorraquidiano , Meningite/diagnóstico , Meningite/imunologia , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/imunologia , Neurite (Inflamação)/líquido cefalorraquidiano , Neurite (Inflamação)/diagnóstico , Neurite (Inflamação)/imunologia , Valor Preditivo dos Testes , Análise Serial de Proteínas , Regulação para Cima/imunologia
4.
Clin Microbiol Infect ; 10(12): 1108-32, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15606643

RESUMO

Ticks are obligate haematophagous acarines that parasitise every class of vertebrate (including man) and have a worldwide distribution. An increasing awareness of tick-borne diseases among clinicians and scientific researchers has led to the recent description of a number of emerging tick-borne bacterial diseases. Since the identification of Borrelia burgdorferi as the agent of Lyme disease in 1982, 11 tick-borne human bacterial pathogens have been described in Europe. Aetiological diagnosis of tick-transmitted diseases is often difficult and relies on specialised laboratories using very specific tools. Interpretation of laboratory data is very important in order to establish the diagnosis. These guidelines aim to help clinicians and microbiologists in diagnosing infection transmitted by tick bites and to provide the scientific and medical community with a better understanding of these infectious diseases.


Assuntos
Vetores Artrópodes/microbiologia , Doenças Transmitidas por Carrapatos/diagnóstico , Carrapatos/microbiologia , Animais , Europa (Continente)/epidemiologia , Humanos , Doenças Transmitidas por Carrapatos/epidemiologia
5.
Nucleic Acids Res ; 32(20): 6038-46, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15547252

RESUMO

Three members of the genus Borrelia (B.burgdorferi, B.garinii, B.afzelii) cause tick-borne borreliosis. Depending on the Borrelia species involved, the borreliosis differs in its clinical symptoms. Comparative genomics opens up a way to elucidate the underlying differences in Borrelia species. We analysed a low redundancy whole-genome shotgun (WGS) assembly of a B.garinii strain isolated from a patient with neuroborreliosis in comparison to the B.burgdorferi genome. This analysis reveals that most of the chromosome is conserved (92.7% identity on DNA as well as on amino acid level) in the two species, and no chromosomal rearrangement or larger insertions/deletions could be observed. Furthermore, two collinear plasmids (lp54 and cp26) seem to belong to the basic genome inventory of Borrelia species. These three collinear parts of the Borrelia genome encode 861 genes, which are orthologous in the two species examined. The majority of the genetic information of the other plasmids of B.burgdorferii is also present in B.garinii although orthology is not easy to define due to a high redundancy of the plasmid fraction. Yet, we did not find counterparts of the B.burgdorferi plasmids lp36 and lp38 or their respective gene repertoire in the B.garinii genome. Thus, phenotypic differences between the two species could be attributable to the presence or absence of these two plasmids as well as to the potentially positively selected genes.


Assuntos
Grupo Borrelia Burgdorferi/classificação , Grupo Borrelia Burgdorferi/genética , Genoma Bacteriano , Borrelia burgdorferi/genética , Grupo Borrelia Burgdorferi/isolamento & purificação , Cromossomos Bacterianos , Evolução Molecular , Humanos , Doença de Lyme/microbiologia , Dados de Sequência Molecular , Mutação , Plasmídeos/genética
6.
Artigo em Alemão | MEDLINE | ID: mdl-15205761

RESUMO

The importance of tick-borne diseases has significantly increased objectively and subjectively during the last few years. This fact was demonstrated by the description of tick-borne viruses, in particular with respect to tickborne encephalitis published in part I. Here in part II, tick-borne bacteria and parasites will be discussed as well the significance of these agents, their vectors, clinical course, diagnostics, prophylaxis, and therapy. Naturally, Lyme borreliosis, one of the most important tick-borne bacterial illnesses of humans, is the center of our interest. In addition to basic understanding, critical practice-relevant advice regarding all agents is presented. Similarly all tick-borne bacterial diseases such as relapsing fever, tularemia, ehrlichiosis, and rickettsiosis including Q fever will be discussed. Tick-borne zoonotic babesiae are parasites whose veterinary importance has been known for the last 100 years but whose relevance for human medicine only became evident in 1957. The fact that multiple and mixed infections caused by ticks are possible has been known for years. Taking into account such a high prevalence of the infectious agents in ticks, such multiple infections were to be expected. During the last few years it has become evident that double and multiple infections of humans caused by tick bites occur far more frequently than has been known so far. As a result, in cases of unclear anamnesis,new diagnostic and therapeutic approaches should be taken. In general one can say that considerable additional scientific research is necessary to effectively reduce the incidence of tick-borne diseases.


Assuntos
Doenças Transmitidas por Carrapatos , Anaplasmose/diagnóstico , Anaplasmose/tratamento farmacológico , Antibacterianos/uso terapêutico , Babesiose/diagnóstico , Babesiose/tratamento farmacológico , Pesquisa Biomédica , Diagnóstico Diferencial , Ehrlichiose/diagnóstico , Ehrlichiose/tratamento farmacológico , Ehrlichiose/prevenção & controle , Humanos , Hospedeiro Imunocomprometido , Doença de Lyme/diagnóstico , Doença de Lyme/tratamento farmacológico , Febre Q/diagnóstico , Febre Q/tratamento farmacológico , Febre Q/prevenção & controle , Febre Recorrente/diagnóstico , Febre Recorrente/tratamento farmacológico , Febre Recorrente/prevenção & controle , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/tratamento farmacológico , Infecções por Rickettsia/prevenção & controle , Fatores de Risco , Doenças Transmitidas por Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/tratamento farmacológico , Doenças Transmitidas por Carrapatos/prevenção & controle , Tularemia/diagnóstico , Tularemia/tratamento farmacológico , Tularemia/prevenção & controle , Zoonoses
8.
Med Microbiol Immunol ; 193(4): 219-26, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-13680214

RESUMO

We describe a sensitive and reliable method for detection and differentiation of the five relevant European Borrelia burgdorferi sensu lato species ( B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. valaisiana, and B. lusitaniae), based on a heminested ospA-PCR followed by restriction enzyme analysis. Sensitivity was one borrelia per PCR except for B. afzelii, where it was five per PCR. None of seven relapsing fever borreliae, eight Leptospira serovars or two Treponema species were amplified. Except B. garinii, each of the five B. burgdorferi s.l. species is represented by one or two characteristic restriction fragment length polymorphism (RFLP) patterns. Analysis of the heterogeneous group of B. garinii resulted in five different RFLP patterns, corresponding to the OspA types 3-7 associated with this species. In a pilot study on 529 Ixodes ricinus ticks from three different regions in Southern Germany, all species and OspA types were found except B. lusitaniae and B. garinii OspA type 7, arguing for a broad distribution of almost all OspA types. A further notable finding was the focal prevalence of OspA type 4, which has rarely been detected in ticks previously. Thus, the developed method provides a fast and simple tool for epidemiological studies on the heterogeneity of species and OspA types in Europe which has important implications for the development of vaccines and (microbiological) test systems for Europe.


Assuntos
Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Borrelia burgdorferi/classificação , Borrelia burgdorferi/isolamento & purificação , Lipoproteínas/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Animais , Técnicas de Tipagem Bacteriana/métodos , Vacinas Bacterianas , Impressões Digitais de DNA/métodos , DNA Bacteriano/análise , Genes Bacterianos , Genótipo , Alemanha , Ixodes/microbiologia , Leptospira/genética , Leptospira/isolamento & purificação , Epidemiologia Molecular/métodos , Sensibilidade e Especificidade , Treponema/genética , Treponema/isolamento & purificação
9.
Eur J Clin Microbiol Infect Dis ; 22(6): 364-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12783276

RESUMO

A total of 305 Ixodes ricinus ticks collected from three areas of Thuringia in central Germany were investigated for infection with Borrelia burgdorferi sensu lato species and Anaplasma phagocytophila. Overall, 11.1% were infected with Borrelia burgdorferi and 2.3% with Anaplasma phagocytophila. Adult ticks showed a significantly higher rate of infection with both borreliae and Anaplasma phagocytophila. Borrelia garinii (55.9%) was detected most frequently, followed by Borrelia burgdorferi sensu stricto (32.4%), Borrelia afzelii (17.6%), and Borrelia valaisiana (5.9%). Four ticks had dual infection with Borrelia garinii and Borrelia burgdorferi sensu stricto. Two of the Borrelia-positive ticks were coinfected with Anaplasma phagocytophila.


Assuntos
Anaplasma/isolamento & purificação , Grupo Borrelia Burgdorferi/isolamento & purificação , Ixodes/microbiologia , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Infestações por Carrapato/epidemiologia , Adulto , Distribuição por Idade , Animais , Comorbidade , DNA Bacteriano/análise , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , Infestações por Carrapato/diagnóstico
10.
J Clin Microbiol ; 40(12): 4735-7, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12454181

RESUMO

Among Borrelia burgdorferi sensu lato isolates, seven outer surface protein A (OspA) serotypes have been described: serotypes 1 and 2 correspond to B. burgdorferi sensu stricto and Borrelia afzelii, respectively, and serotypes 3 to 7 correspond to Borrelia garinii. In Europe, serotype 4 has never been isolated from Ixodes ricinus ticks until recently, although this serotype has been frequently isolated from cerebrospinal fluid from patients. In Europe, B. afzelii and B. burgdorferi sensu stricto were found associated with rodents and B. garinii was found associated with birds. In this study, the reservoir role of Apodemus mice for B. garinii OspA serotype 4 was demonstrated by xenodiagnosis. Apodemus mice are the first identified reservoir hosts for B. garinii OspA serotype 4.


Assuntos
Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Grupo Borrelia Burgdorferi/classificação , Reservatórios de Doenças , Ixodes/microbiologia , Lipoproteínas , Muridae/microbiologia , Animais , Vacinas Bacterianas , Grupo Borrelia Burgdorferi/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/química , Sorotipagem , Suíça
13.
MMW Fortschr Med ; 144(22): 29-32, 2002 May 30.
Artigo em Alemão | MEDLINE | ID: mdl-12116568

RESUMO

Lyme borreliosis is the most common of the infectious diseases transmitted by ticks in the Northern hemisphere. In Europe, Lyme borreliosis can be caused by three species of Borrelia: B. burgdorferi sensu stricto, B. garinii and B. afzelii. The microbiological diagnosis is established primarily on the basis of antibody detection, and secondarily by detection of the pathogen itself. Suitable material for the detection of the latter are various body fluids (CSF, joint fluid and biopsy material, in particular in the skin). In the case of antibodies, the substrate is usually serum. If neuroborreliosis is suspected, CSF should always be investigated (CSF/serum, pairwise, same day!). The microbiological findings must be interpreted in conjunction with the clinical presentation. A negative serological result does not exclude an early manifestation, a positive finding is no proof of a clinically manifest infection--it might be a titer from an earlier infection.


Assuntos
Doença de Lyme/diagnóstico , Anticorpos Antibacterianos/sangue , Técnicas Bacteriológicas , Borrelia burgdorferi/imunologia , Borrelia burgdorferi/isolamento & purificação , Diagnóstico Diferencial , Humanos , Doença de Lyme/imunologia , Doença de Lyme/microbiologia , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes
14.
J Infect Dis ; 184(11): 1445-50, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11709787

RESUMO

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 degrees C did not 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.


Assuntos
Antígenos de Bactérias/metabolismo , Vetores Aracnídeos/microbiologia , Ehrlichia/metabolismo , Ehrlichiose/microbiologia , Epitopos/metabolismo , Ixodes/microbiologia , Animais , Anticorpos Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/imunologia , Western Blotting , Linhagem Celular , Ehrlichia/imunologia , Ehrlichiose/transmissão , Epitopos/imunologia , Células HL-60 , Humanos , Cinética , Temperatura
15.
Med Microbiol Immunol ; 189(4): 193-200, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11599789

RESUMO

OspC and Osp17 are immunodominant proteins of Borrelia burgdorferi eliciting a clear humoral immune response in adult patients with systemic Lyme disease. In this study, the cellular immune response to B. burgdorferi and the major outer surface proteins OspC and Osp17 was investigated in children during the course of early disseminated B. burgdorferi infection. Lymphoproliferative responses to recombinant proteins were compared to the protein-specific humoral immune reaction. OspC induced a clear antibody response but elicited an even stronger cellular immune response. In contrast, a cellular as well as humoral immune reaction to Osp17 was only rarely detected. Follow-up examinations demonstrated that the lymphoproliferative response to B. burgdorferi and OspC persisted for several months after antibiotic therapy. Here, we show that in early disseminated Lyme disease of childhood, OspC is a potent antigen influencing both the humoral and cellular immunity, while Osp17 plays only a minor role in immune activation.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias , Proteínas da Membrana Bacteriana Externa/imunologia , Borrelia burgdorferi/imunologia , Doença de Lyme/imunologia , Ativação Linfocitária/imunologia , Adolescente , Proteínas da Membrana Bacteriana Externa/genética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Doença de Lyme/microbiologia , Masculino , Linfócitos T/imunologia
17.
Brain ; 124(Pt 7): 1325-35, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408328

RESUMO

Chronic intrathecal immunoglobulin (Ig) production is a hallmark of multiple sclerosis characterized by the presence of oligoclonal IgGs and, in addition, polyspecific recognition of different pathogens such as measles, rubella and herpes zoster virus. While the antigen specificity of the oligoclonal IgGs in multiple sclerosis is largely unknown, the oligoclonal IgGs arising during CNS infectious diseases are reactive against the specific pathogen. Recently, a link between Chlamydia pneumoniae and multiple sclerosis has been claimed. To test the possible role of C. pneumoniae in multiple sclerosis, we analysed (i) whether there is intrathecal IgG production against C. pneumoniae in multiple sclerosis and (ii) if the oligoclonal IgGs in the CSF of multiple sclerosis patients recognize C. pneumoniae. By studying paired serum-CSF samples from 120 subjects (definite multiple sclerosis, 46; probable multiple sclerosis, 12; other inflammatory neurological diseases, 35; other neurological diseases, 27) by enzyme-linked immunosorbent assay, we found that 24% of all patients with definite multiple sclerosis, but only 5% of patients with other inflammatory or non-inflammatory diseases, produced IgGs specific for C. pneumoniae intrathecally (definite multiple sclerosis versus other inflammatory neurological diseases: P = 0.027). The presence of intrathecal IgGs to C. pneumoniae was independent of the duration of disease and relatively stable over time. The major CSF oligoclonal IgG bands from multiple sclerosis patients with an intrathecal Ig production to C. pneumoniae did not react towards purified elementary bodies and reticulate bodies of C. pneumoniae on affinity-mediated immunoblot following isoelectric focusing (IEF-western blots). In contrast, the IgGs in the CSF of control patients with neuroborreliosis strongly reacted with their specific pathogen, Borrelia burgdorferi, by IEF-western blot analysis. Concomitant analysis of the CSF of 23 patients with a nested polymerase chain reaction for C. pneumoniae was negative in all cases. Together, our findings strongly suggest that the immune response to C. pneumoniae is part of a polyspecific intrathecal Ig production, as is commonly observed with other pathogens. This argues against a specific role for C. pneumoniae in multiple sclerosis.


Assuntos
Especificidade de Anticorpos/imunologia , Infecções por Chlamydophila/imunologia , Chlamydophila pneumoniae/imunologia , Imunoglobulina G/imunologia , Esclerose Múltipla/imunologia , Animais , Western Blotting , Grupo Borrelia Burgdorferi/imunologia , Causalidade , Linhagem Celular , Infecções por Chlamydophila/líquido cefalorraquidiano , Infecções por Chlamydophila/epidemiologia , Chlamydophila pneumoniae/genética , Chlamydophila pneumoniae/isolamento & purificação , Cromatografia de Afinidade , Doença Crônica , Comorbidade , Epitopos/imunologia , Seguimentos , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Focalização Isoelétrica , Neuroborreliose de Lyme/imunologia , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/microbiologia , Reação em Cadeia da Polimerase , Estudos Soroepidemiológicos
18.
J Clin Microbiol ; 39(3): 1169-71, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11230451

RESUMO

In Europe, Borrelia garinii OspA serotype 4 has been isolated from the cerebrospinal fluid of patients but, up to now, has never been identified among culture isolates from Ixodes ricinus ticks. This information raises the question of whether OspA serotype 4 is transmitted by I. ricinus in nature. In the present study, I. ricinus nymphs collected in an area of endemicity in southern Germany were allowed to feed on mice. Cultivation of ear biopsy specimens showed that six of seven B. garinii-infected mice were infected by OspA serotype 4. In contrast, very few B. garinii OspA serotype 4 organisms were isolated directly from the ticks which infected the mice; most isolates were B. afzelii. The infected mice transmitted mainly OspA serotype 4 to xenodiagnostic ticks, preferentially in combination with B. afzelii.


Assuntos
Antígenos de Superfície/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Infecções por Borrelia/microbiologia , Infecções por Borrelia/transmissão , Borrelia/classificação , Borrelia/fisiologia , Ixodes/microbiologia , Lipoproteínas , Vacinas contra Doença de Lyme/metabolismo , Animais , Vacinas Bacterianas , Borrelia/genética , Feminino , Ixodes/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Sorotipagem
19.
Infect Immun ; 69(3): 1739-46, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11179351

RESUMO

Lyme borreliosis is a multisystemic disorder primarily affecting the skin, nervous system, and joints. It is caused by the spirochete Borrelia burgdorferi sensu lato and is transmitted via ticks of the Ixodidae family. Persistence of borreliae within macrophages has been implicated in the often chronic history of borreliosis. The uptake of B. burgdorferi by professional phagocytes occurs predominantly by coiling phagocytosis, a host cell-driven process in which single pseudopods wrap around and engulf the spirochetes. In the present study, we investigated the molecular machinery and the signal transduction pathways controlling the formation of these unique uptake structures. We found that the phagocytosis of borreliae by primary human macrophages is accompanied by the formation of f-actin-rich structures, which in their morphological organization correspond well to the earlier described coiling pseudopods. Further experiments revealed that Wiskott-Aldrich Syndrome protein and Arp2/3 complex, major regulators of actin polymerization, are also recruited to these sites of actin accumulation. In addition, inhibition of an upstream regulator of Wiskott-Aldrich Syndrome protein, the Rho-family GTPase CDC42Hs, greatly inhibited the occurrence of borrelia-induced phagocytic uptake structures. Inhibition of Rac1, another Rho family GTPase, had a less-pronounced inhibitory effect, while blocking of Rho activity showed no discernible influence. These results suggest that basic mechanisms of actin polymerization that control other types of phagocytosis are also functional in the formation of the morphologically unique uptake structures in coiling phagocytosis. Our findings should enhance the understanding of the infection process of B. burgdorferi and contribute to devising new strategies for countering Lyme disease.


Assuntos
Actinas/metabolismo , Grupo Borrelia Burgdorferi/imunologia , Proteínas do Citoesqueleto , Macrófagos/imunologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fagocitose , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Grupo Borrelia Burgdorferi/patogenicidade , Grupo Borrelia Burgdorferi/ultraestrutura , Macrófagos/ultraestrutura , Proteínas Tirosina Quinases/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Proteína da Síndrome de Wiskott-Aldrich , Proteínas rac1 de Ligação ao GTP/metabolismo
20.
Br J Dermatol ; 143(4): 780-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11069456

RESUMO

BACKGROUND: The aetiology of morphoea is still unknown. Borrelia burgdorferi as a causative agent of morphoea has been discussed since 1985, but the relationship remains uncertain. OBJECTIVES: We aimed to find evidence for infection with B. burgdorferi by combined evaluation of different clinical and laboratory data in a group of 54 patients with morphoea. METHODS: In each patient, an evaluation of the case history was performed with regard to infection with B. burgdorferi, using a standardized questionnaire. Questions focused on previous tick bites and skin changes suspicious for erythema migrans (EM). The case history data of 52 patients were compared with those of 104 matched control subjects and of 25 patients with acrodermatitis chronica atrophicans (ACA). Serological examinations were performed in 53 patients with morphoea. Furthermore, lesional skin was examined for borrelial DNA in 33 patients, using nested polymerase chain reaction (PCR) for the ospA and the borrelial rRNA gene. RESULTS: Results of the questionnaire showed no differences between patients with morphoea and matched controls. In contrast, patients with ACA showed a much higher prevalence of tick bites and skin changes suspicious for EM as compared with patients with morphoea. Serological examination was positive in only one patient with morphoea alone and in two additional patients with coexistent ACA. No borrelial DNA was detected by PCR in lesional skin of 33 patients with morphoea. CONCLUSIONS: No evidence was found for B. burgdorferi infection in patients with morphoea.


Assuntos
Grupo Borrelia Burgdorferi/isolamento & purificação , Doença de Lyme/complicações , Esclerodermia Localizada/microbiologia , Dermatopatias Bacterianas/microbiologia , Adolescente , Adulto , Idoso , Animais , Anticorpos Antibacterianos/sangue , Mordeduras e Picadas/complicações , Grupo Borrelia Burgdorferi/imunologia , Criança , Pré-Escolar , DNA Bacteriano/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Carrapatos
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