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Studies on the Weil-Felix Reaction of Rickettsia tsutsugamushi The Investigatign on the Weil-Felix Reaction on the Basis of the Concept of 50% Agglutination Titer
Full text linkFor the diagnosis of rickettsial diseases, though there are agglutination and complement fixation tests with the use of pure rickettsial suspension, the Weil-Felix test is still of high value for its technical simplicity and specificity. Even in the case of Tsutsugamushi disease, Fletcher, Wolf, Felix and Kawamura applied the Weil-Felix reaction with the use of Proteus OXK bacilli, and since then this reaction has been discussed in various ways, but the true antibody titer seems not to be obtained because of the insufficient consideration of the antigen concentration. Especially when the variation in the production of antibody is discussed on the basis of antibody titer, there apt to be misinterpretations. By the Weil-Felix reaction with the use of Proteus OXK dacilli suspension of 50% agglutination titer as the antigen, the author examined the variation of the antibody production in the sera of the test animals inoculated with rickettsiae, in parallel with the case in which the antigen was selected at random in the conventional way. As the result, it was found that when the antigen of 50% agglutination titer was used, no variation was shown in the antibody titer, irrespective of the sites of inoculation, the number of times of inoculation, life or death of rickettsiae, while, in the case of antigen selected at random, variable titers were yielded. From these data, the author believes that the antigen concentration suitable for she Weil-Felix reaction has been found
Weil-Felix反応に関する研究50%凝集価の概念にもとずくWeil-Felix反応の吟味
No full textFor the diagnosis of rickettsial diseases, though there are agglutination and complement fixation tests with the use of pure rickettsial suspension, the Weil-Felix test is still of high value for its technical simplicity and specificity. Even in the case of Tsutsugamushi disease, Fletcher, Wolf, Felix and Kawamura applied the Weil-Felix reaction with the use of Proteus OXK bacilli, and since then this reaction has been discussed in various ways, but the true antibody titer seems not to be obtained because of the insufficient consideration of the antigen concentration. Especially when the variation in the production of antibody is discussed on the basis of antibody titer, there apt to be misinterpretations. By the Weil-Felix reaction with the use of Proteus OXK dacilli suspension of 50% agglutination titer as the antigen, the author examined the variation of the antibody production in the sera of the test animals inoculated with rickettsiae, in parallel with the case in which the antigen was selected at random in the conventional way. As the result, it was found that when the antigen of 50% agglutination titer was used, no variation was shown in the antibody titer, irrespective of the sites of inoculation, the number of times of inoculation, life or death of rickettsiae, while, in the case of antigen selected at random, variable titers were yielded. From these data, the author believes that the antigen concentration suitable for she Weil-Felix reaction has been found
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<i>Rickettsia conorii</i> O antigen is the target of bactericidal Weil–Felix antibodies
Full text linkRickettsial diseases have long been diagnosed with serum antibodies cross-reactive against Proteus vulgaris (Weil–Felix reaction). Although Weil–Felix antibodies are associated with the development of immunity, their rickettsial target and contribution to disease pathogenesis are not established. Here, we developed a transposon for insertional mutagenesis of Rickettsia conorii, isolating variants defective for replication in cultured cells and in spotted fever pathogenesis. Mutations in the polysaccharide synthesis operon (pso) abolish lipopolysaccharide O-antigen synthesis and Weil–Felix serology and alter outer-membrane protein assembly. Unlike wild-type R. conorii, pso mutants cannot elicit bactericidal antibodies that bind O antigen. The pso operon is conserved among rickettsial pathogens, suggesting that bactericidal antibodies targeting O antigen may generate universal immunity that could be exploited to develop vaccines against rickettsial diseases
Agglutinazione di Weil-Felix nei topi di Messina
No full textÉ stata eseguita la reazione di Weil-Felix sul sangue di 94 topi catturati a Messina. Si sono avute in totale sette agglutinazioni positive, delle quali una al titolo di I:200, tre I:100 e tre a titolo inferiore. Valutando come risultati positivi quelli da I:100 in su si ricava una percentuale del 4,25% di topi che presentano agglutinine per i protei X_1_9 e
A reação de Weil-Felix em soros provenientes de Belém e outras localidades da Amazônia (Publicado originalmente em 1960)
No full textMinistério da Educação e Saúde. Serviço Especial de Saúde Pública. Instituto Evandro. Belém, PA, Brasil.Foram submetidos à reação de Weil-Felix soros de 159
doentes febris de 16 localidades da região amazônica. Os resultados
foram negativos para estabelecer a existência de rickettsioses na área
estudada.
O autor levará a efeito novas investigações usando a reação
de Weil-Felix e provas de fixação de complemento com antígeno de
rickettsias em soros de habitantes da região amazônica e em soros de
ratos capturados em Belém
Studies on the Antigenicity of Bacterial Polysaccharides Part 2: On the Relationship Between Precipitation by B. Proteus X19 Polysaccharide and Weil-Felix Reaction
Full text linkWith the use of polysaccharide of B. Proteus X19 extracted by trichloracetate method, the author has performed precipitation between this polysaccharide and anti-serum of the rabbit immunized with Proteus X19 on one hand, and this polysaccharide against serum of Febris exanthematicus patient and serum of those having anamnesis of typhus exanthematicus and Febris exanthematicus on the other hand; and comparing these results with those with Weil-Felix reaction performed concomitantly, the following results have been finally obtained. 1) In the precipitation with anti-Proteus X19 rabbit serum by antigen-antibody-dilution method, various values have been found to be: antigen titer, 1:50,000; antibody titer, 1:25; and antigen titer of binding zone, 1:10,000; while the agglutination titer has been 1:2,500. 2) Antibody has remained in those patients having anamnesis of typhus exanthematicus or Febris exanthematicus. In the precipitation with their serum antigen titer has been fonnd to be 1:250-1:2,500; while the agglutination by Weil-Felix reaction has been 1:100-1:500. Furthermore, in the precipitation with serum of Febris exanthematicus patient antigen titer has been found to be 1:250-1:1,000; while the agglutination titer is 1:250-1:1,000. 3) The antigen titer of precipitation runs parallel to the agglutination titer of Weil-Felix reaction. 4) This polysaccharide seems to possess a special feature which makes it possible to be kept for a long period of time
A hospital based study of rickettsial diseases evidenced by Weil Felix test in a tertiary care hospital
No full textIntroduction: Rickettsial infections, one of the re-emerging diseases are increasingly underdiagnosed due to nonspecific symptoms, absence of reliable and affordable diagnostic test and contribute substantially to the acute febrile burden and preventive illness in many populations. A delay in diagnosis and therapy are associated with increased morbidity and mortality. Objectives: To determine and categorize rickettsial disease titers by Weil Felix test, and to know the frequency of rickettsial diseases in febrile patients presenting to a tertiary hospital. Materials and Methods: In a prospective study, a total of 100 samples were tested by Weil Felix test from patients with fever and results were analyzed. Results: Out of 100 samples 64 were positive. Male preponderance was seen. The most common clinical symptom were fever, rash followed by hepatomegaly and splenomegaly. One patient with a high titer of more than 1280 died of encephalitis. Conclusion: In the absence of availability of a good reliable serological or molecular evidence, Weil Felix test can be used in the laboratories mainly due to cost and technical aspects of other reliable tests for diagnosis
細菌多糖類の抗原性に関する研究 第2編 Proteus X19菌多糖類の沈降反応とWeil-Felix反応の関係に就いて
No full textWith the use of polysaccharide of B. Proteus X19 extracted by trichloracetate method, the author has performed precipitation between this polysaccharide and anti-serum of the rabbit immunized with Proteus X19 on one hand, and this polysaccharide against serum of Febris exanthematicus patient and serum of those having anamnesis of typhus exanthematicus and Febris exanthematicus on the other hand; and comparing these results with those with Weil-Felix reaction performed concomitantly, the following results have been finally obtained. 1) In the precipitation with anti-Proteus X19 rabbit serum by antigen-antibody-dilution method, various values have been found to be: antigen titer, 1:50,000; antibody titer, 1:25; and antigen titer of binding zone, 1:10,000; while the agglutination titer has been 1:2,500. 2) Antibody has remained in those patients having anamnesis of typhus exanthematicus or Febris exanthematicus. In the precipitation with their serum antigen titer has been fonnd to be 1:250-1:2,500; while the agglutination by Weil-Felix reaction has been 1:100-1:500. Furthermore, in the precipitation with serum of Febris exanthematicus patient antigen titer has been found to be 1:250-1:1,000; while the agglutination titer is 1:250-1:1,000. 3) The antigen titer of precipitation runs parallel to the agglutination titer of Weil-Felix reaction. 4) This polysaccharide seems to possess a special feature which makes it possible to be kept for a long period of time
Structures of the O-antigens of Proteus bacilli belonging to OX group (serogroups O1–O3) used in Weil-Felix test
No full textAbstractStructures of the O-specific polysaccharide chains of lipopolysaccharides from Proteus group OX strains (serogroups O1–O3) used as antigens in Weil-Felix test for diagnosis of rickettsiosis, were established. From them, the acid-labile polysaccharide of Proteus vulgaris OX19 (O1) is built up of the following branched pentasaccharide repeating units connected via a phosphate group:where QuiNAc stands for 2-acetamido-2,6-dideoxyglucose (N-acetylquinovosamine). The basis of serospecificity of the Proteus group OX antigens and their cross-reactivity with human anti-rickettsial antibodies is discussed
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