Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.811-817.2001
Y. Nishikawa, K. Tragoolpua, N. Inoue, L. Makala, H. Nagasawa, H. Otsuka, T. Mikami
ABSTRACT Following infection with Neospora caninum, BALB/c mice were shown to be resistant to an acute infection but developed a latent chronic infection. However, BALB/c background gamma interferon (IFN-γ)-deficient mice were sensitive to the acute infection. Since the immune response in IFN-γ-deficient mice is scantly known, we examined the function of macrophages, major histocompatibility complex (MHC) class II expression, T-cell responses, and serum cytokine levels in the mice. All IFN-γ-deficient mice died within 9 days of infection with N. caninum, whereas those treated with exogenous IFN-γ lived longer. Although N. caninum invaded various organs in both types of mice at the early stage of infection, the parasite was not detected in the brains of resistant hosts until 21 days postinfection (dpi). Peritoneal macrophages from IFN-γ-deficient mice were activated by exogenous IFN-γ associated with inhibition of parasite growth and nitric oxide production as were those from BALB/c mice. IFN-γ-deficient mice failed to increase MHC class II expression on macrophages. Moreover, BALB/c mice induced T-cell proliferation while IFN-γ-deficient mice did not. However, in vivo treatment with exogenous IFN-γ induced up-regulated MHC class II expression in IFN-γ-deficient mice. BALB/c mice treated with an antibody to CD4 showed an increase in morbidity and mortality after parasite infection. In serum, significant levels of IFN-γ and interleukin-4 (IL-4) were detected in resistant hosts, whereas IL-10 was detected in IFN-γ-deficient mice. The levels of IL-12 in IFN-γ-deficient mice were higher than those in BALB/c mice at 7 dpi. The present study indicates that early IFN-γ production has a crucial role in the activation of peritoneal macrophages for the induction of protective immune responses againstN. caninum.
{"title":"In the Absence of Endogenous Gamma Interferon, Mice Acutely Infected with Neospora caninum Succumb to a Lethal Immune Response Characterized by Inactivation of Peritoneal Macrophages","authors":"Y. Nishikawa, K. Tragoolpua, N. Inoue, L. Makala, H. Nagasawa, H. Otsuka, T. Mikami","doi":"10.1128/CDLI.8.4.811-817.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.811-817.2001","url":null,"abstract":"ABSTRACT Following infection with Neospora caninum, BALB/c mice were shown to be resistant to an acute infection but developed a latent chronic infection. However, BALB/c background gamma interferon (IFN-γ)-deficient mice were sensitive to the acute infection. Since the immune response in IFN-γ-deficient mice is scantly known, we examined the function of macrophages, major histocompatibility complex (MHC) class II expression, T-cell responses, and serum cytokine levels in the mice. All IFN-γ-deficient mice died within 9 days of infection with N. caninum, whereas those treated with exogenous IFN-γ lived longer. Although N. caninum invaded various organs in both types of mice at the early stage of infection, the parasite was not detected in the brains of resistant hosts until 21 days postinfection (dpi). Peritoneal macrophages from IFN-γ-deficient mice were activated by exogenous IFN-γ associated with inhibition of parasite growth and nitric oxide production as were those from BALB/c mice. IFN-γ-deficient mice failed to increase MHC class II expression on macrophages. Moreover, BALB/c mice induced T-cell proliferation while IFN-γ-deficient mice did not. However, in vivo treatment with exogenous IFN-γ induced up-regulated MHC class II expression in IFN-γ-deficient mice. BALB/c mice treated with an antibody to CD4 showed an increase in morbidity and mortality after parasite infection. In serum, significant levels of IFN-γ and interleukin-4 (IL-4) were detected in resistant hosts, whereas IL-10 was detected in IFN-γ-deficient mice. The levels of IL-12 in IFN-γ-deficient mice were higher than those in BALB/c mice at 7 dpi. The present study indicates that early IFN-γ production has a crucial role in the activation of peritoneal macrophages for the induction of protective immune responses againstN. caninum.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"88 1","pages":"811 - 817"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84916547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.788-796.2001
M. Eremeeva, G. Dasch, D. Silverman
ABSTRACT Eleven isolates of spotted fever group rickettsiae from the blood of patients or ixodid ticks from North and South America were characterized. All isolates were identified as Rickettsia rickettsii using restriction fragment length polymorphism analysis of a 532-bp rOmpA gene fragment obtained by PCR. The ability of the R. rickettsii isolates to elicit cytopathic effects and parameters of oxidative injury were examined in cultured human EA.hy 926 endothelial cells. Cytopathic effects were determined by direct observation of infected cultures, by measuring the release of cytoplasmic lactate dehydrogenase (LDH), and by determination of intracellular pools of peroxide and reduced glutathione. Four biotypes of R. rickettsii were defined. Group I included two highly cytopathic isolates from Montana, Bitterroot and Sheila Smith, and three isolates from Maryland, North Carolina, and Brazil. These isolates rapidly damaged cells, released large amounts of cytoplasmic LDH, caused accumulation of intracellular peroxide, and depleted intracellular pools of reduced glutathione. Group II contained three isolates, two from Montana, Hlp#2 and Lost Horse Canyon, and an isolate from Colombia, which were similar to group I but caused either lower responses in LDH release or smaller changes in intracellular peroxide levels. The group III isolates, Sawtooth from Montana and 84JG from North Carolina, caused lower cellular injury by all measures. Group IV isolate Price T from Montana was the least cytopathic and caused minimal alterations of all parameters measured. Understanding the molecular basis for the varied cellular injury caused by different isolates of R. rickettsii may contribute to improved treatment of Rocky Mountain spotted fever and to the rapid identification of those isolates which are more likely to cause fulminant disease.
{"title":"Quantitative Analyses of Variations in the Injury of Endothelial Cells Elicited by 11 Isolates of Rickettsia rickettsii","authors":"M. Eremeeva, G. Dasch, D. Silverman","doi":"10.1128/CDLI.8.4.788-796.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.788-796.2001","url":null,"abstract":"ABSTRACT Eleven isolates of spotted fever group rickettsiae from the blood of patients or ixodid ticks from North and South America were characterized. All isolates were identified as Rickettsia rickettsii using restriction fragment length polymorphism analysis of a 532-bp rOmpA gene fragment obtained by PCR. The ability of the R. rickettsii isolates to elicit cytopathic effects and parameters of oxidative injury were examined in cultured human EA.hy 926 endothelial cells. Cytopathic effects were determined by direct observation of infected cultures, by measuring the release of cytoplasmic lactate dehydrogenase (LDH), and by determination of intracellular pools of peroxide and reduced glutathione. Four biotypes of R. rickettsii were defined. Group I included two highly cytopathic isolates from Montana, Bitterroot and Sheila Smith, and three isolates from Maryland, North Carolina, and Brazil. These isolates rapidly damaged cells, released large amounts of cytoplasmic LDH, caused accumulation of intracellular peroxide, and depleted intracellular pools of reduced glutathione. Group II contained three isolates, two from Montana, Hlp#2 and Lost Horse Canyon, and an isolate from Colombia, which were similar to group I but caused either lower responses in LDH release or smaller changes in intracellular peroxide levels. The group III isolates, Sawtooth from Montana and 84JG from North Carolina, caused lower cellular injury by all measures. Group IV isolate Price T from Montana was the least cytopathic and caused minimal alterations of all parameters measured. Understanding the molecular basis for the varied cellular injury caused by different isolates of R. rickettsii may contribute to improved treatment of Rocky Mountain spotted fever and to the rapid identification of those isolates which are more likely to cause fulminant disease.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"8 1","pages":"788 - 796"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81841315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.841-842.2001
M. Fears, V. Pope
ABSTRACT Using 255 serum samples with various reactivities, we evaluated the Syphilis Fast latex agglutination test (Syphilis Fast) against theTreponema pallidum particle agglutination test (TP-PA) for confirming a diagnosis of syphilis. We found 98.8% agreement between the Syphilis Fast and the TP-PA. The Syphilis Fast, however, had a couple of advantages over the TP-PA: the test takes only 8 min to perform and produces results that are easy to read. It appears to be a good confirmatory test for syphilis, especially for point-of-care clinics such as prenatal or sexually transmitted disease clinics.
{"title":"Syphilis Fast Latex Agglutination Test, a Rapid Confirmatory Test","authors":"M. Fears, V. Pope","doi":"10.1128/CDLI.8.4.841-842.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.841-842.2001","url":null,"abstract":"ABSTRACT Using 255 serum samples with various reactivities, we evaluated the Syphilis Fast latex agglutination test (Syphilis Fast) against theTreponema pallidum particle agglutination test (TP-PA) for confirming a diagnosis of syphilis. We found 98.8% agreement between the Syphilis Fast and the TP-PA. The Syphilis Fast, however, had a couple of advantages over the TP-PA: the test takes only 8 min to perform and produces results that are easy to read. It appears to be a good confirmatory test for syphilis, especially for point-of-care clinics such as prenatal or sexually transmitted disease clinics.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"1949 1","pages":"841 - 842"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91177633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.822-824.2001
L. Sarmati, G. d’Ettorre, E. Nicastri, L. Ercoli, I. Uccella, P. Massetti, S. Parisi, V. Vullo, M. Andreoni
ABSTRACT Antiretroviral-treated human immunodeficiency virus (HIV) type 1-seropositive individuals can remain clinically stable for a long period of time with an increasing CD4 cell count irrespective of incomplete viral suppression. We evaluated the role of neutralizing antibody (NtAb) activity in the etiopathogenesis of this viro-immunological disconnection (defined as an increasing CD4+-cell count despite a persistent, detectable viral load during antiretroviral therapy) in 33 patients failing therapy with two analogue nucleoside reverse transcriptase inhibitors. An HIV NtAb titer of ≥1:25 was detected in specimens from 16 out of 33 (48%) patients. A significant correlation was found between NtAb titers and CD4+-cell counts (P = 0.001;r = 0.546) but not with HIV RNA levels in plasma. Five patients with a viro-immunological disconnection had an NtAb titer of >1:125, statistically higher than the NtAb titers for the remaining 28 patients with both virologic and immunologic failure (P < 0.0001). The HIV-specific humoral immune response could play a role during antiretroviral treatment to improve immunological function despite an incomplete suppression of viral load.
{"title":"Neutralizing Antibodies against Autologous Human Immunodeficiency Virus Type 1 Isolates in Patients with Increasing CD4 Cell Counts despite Incomplete Virus Suppression during Antiretroviral Treatment","authors":"L. Sarmati, G. d’Ettorre, E. Nicastri, L. Ercoli, I. Uccella, P. Massetti, S. Parisi, V. Vullo, M. Andreoni","doi":"10.1128/CDLI.8.4.822-824.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.822-824.2001","url":null,"abstract":"ABSTRACT Antiretroviral-treated human immunodeficiency virus (HIV) type 1-seropositive individuals can remain clinically stable for a long period of time with an increasing CD4 cell count irrespective of incomplete viral suppression. We evaluated the role of neutralizing antibody (NtAb) activity in the etiopathogenesis of this viro-immunological disconnection (defined as an increasing CD4+-cell count despite a persistent, detectable viral load during antiretroviral therapy) in 33 patients failing therapy with two analogue nucleoside reverse transcriptase inhibitors. An HIV NtAb titer of ≥1:25 was detected in specimens from 16 out of 33 (48%) patients. A significant correlation was found between NtAb titers and CD4+-cell counts (P = 0.001;r = 0.546) but not with HIV RNA levels in plasma. Five patients with a viro-immunological disconnection had an NtAb titer of >1:125, statistically higher than the NtAb titers for the remaining 28 patients with both virologic and immunologic failure (P < 0.0001). The HIV-specific humoral immune response could play a role during antiretroviral treatment to improve immunological function despite an incomplete suppression of viral load.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"7 1","pages":"822 - 824"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82518162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.757-761.2001
M. García-Pérez, L. Allende, A. Corell, E. Paz-Artal, P. Varela, A. López-Goyanes, Francisco Garcı́a-Martin, Rosario Vázquez, A. Sotoca, A. Arnaiz-Villena
ABSTRACT Nijmegen breakage syndrome (NBS) is a genetic disorder characterized by immunodeficiency, microcephaly, and “bird-like” facies. NBS shares some clinical features with ataxia telangiectasia (AT), including increased sensitivity to ionizing radiation, increased spontaneous and induced chromosome fragility, and strong predisposition to lymphoid cancers. The mutated gene that results in NBS codes for a novel double-stranded DNA break repair protein, named nibrin. In the present work, a Spanish NBS patient was extensively characterized at the immunological and the molecular DNA levels. He showed low CD3+-cell numbers and an abnormal low CD4+naive cell/CD4+ memory cell ratio, previously described in AT patients and also described in the present report in the NBS patient. The proliferative response of peripheral blood lymphocytes in vitro to mitogens is deficient in NBS patients, but the possible link among NBS mutations and the abnormal immune response is still unknown.
{"title":"Role of Nijmegen Breakage Syndrome Protein in Specific T-Lymphocyte Activation Pathways","authors":"M. García-Pérez, L. Allende, A. Corell, E. Paz-Artal, P. Varela, A. López-Goyanes, Francisco Garcı́a-Martin, Rosario Vázquez, A. Sotoca, A. Arnaiz-Villena","doi":"10.1128/CDLI.8.4.757-761.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.757-761.2001","url":null,"abstract":"ABSTRACT Nijmegen breakage syndrome (NBS) is a genetic disorder characterized by immunodeficiency, microcephaly, and “bird-like” facies. NBS shares some clinical features with ataxia telangiectasia (AT), including increased sensitivity to ionizing radiation, increased spontaneous and induced chromosome fragility, and strong predisposition to lymphoid cancers. The mutated gene that results in NBS codes for a novel double-stranded DNA break repair protein, named nibrin. In the present work, a Spanish NBS patient was extensively characterized at the immunological and the molecular DNA levels. He showed low CD3+-cell numbers and an abnormal low CD4+naive cell/CD4+ memory cell ratio, previously described in AT patients and also described in the present report in the NBS patient. The proliferative response of peripheral blood lymphocytes in vitro to mitogens is deficient in NBS patients, but the possible link among NBS mutations and the abnormal immune response is still unknown.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"65 1","pages":"757 - 761"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79523146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.802-805.2001
I. Marcipar, M. Risso, A. Silber, S. Revelli, A. Marcipar
ABSTRACT The study of antibody avidity changes during infection has improved the understanding of the pathologic processes involved in several infectious diseases. In some infections, like toxoplasmosis, this information is being used for diagnostic purposes. Results of the evolution of antibody avidity for different specific antigens inTrypanosome cruzi-infected rats are presented. A Western blotting technique, combined with avidity analysis to identify antigens that elicit high-avidity antibodies, is suggested. In this system, antibodies showed high avidity values only during the chronic phase of infection and only in relation to antibodies against 21-, 33-, 41-, 42-, 56-, 58-, 66-, and 72-kDa antigens. Finally, a 97-kDa T. cruzi antigen, which was recognized by high-avidity antibodies and occurred in noninfected rats, was identified. These results allow us to evaluate the different antigens in chagasic infection. Our results show that with the correct choice of antigen it is possible to detect differences in maturation of antibodies and to discriminate, in an experimental model, between recent (acute) and chronic infections.
{"title":"Antibody Maturation in Trypanosoma cruzi-Infected Rats","authors":"I. Marcipar, M. Risso, A. Silber, S. Revelli, A. Marcipar","doi":"10.1128/CDLI.8.4.802-805.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.802-805.2001","url":null,"abstract":"ABSTRACT The study of antibody avidity changes during infection has improved the understanding of the pathologic processes involved in several infectious diseases. In some infections, like toxoplasmosis, this information is being used for diagnostic purposes. Results of the evolution of antibody avidity for different specific antigens inTrypanosome cruzi-infected rats are presented. A Western blotting technique, combined with avidity analysis to identify antigens that elicit high-avidity antibodies, is suggested. In this system, antibodies showed high avidity values only during the chronic phase of infection and only in relation to antibodies against 21-, 33-, 41-, 42-, 56-, 58-, 66-, and 72-kDa antigens. Finally, a 97-kDa T. cruzi antigen, which was recognized by high-avidity antibodies and occurred in noninfected rats, was identified. These results allow us to evaluate the different antigens in chagasic infection. Our results show that with the correct choice of antigen it is possible to detect differences in maturation of antibodies and to discriminate, in an experimental model, between recent (acute) and chronic infections.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"13 1","pages":"802 - 805"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73170254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.711-717.2001
P. Feng, M. Dey, A. Abe, T. Takeda
ABSTRACT An Escherichia coli O157:H7 strain isolated from a patient with hemorrhagic colitis was found to exhibit two slightly different colony morphology types on differential medium. Each morphological type, designated TT12A and TT12B, was isolated, and serological testing using various assays confirmed that both strains carried the O157 and the H7 antigens. Biochemical testing showed that the strains had identical profiles on AP120E analysis and, like typical O157:H7 strains, did not ferment sorbitol or exhibit β-glucuronidase activity. Analysis with a multiplex PCR assay showed that TT12B did not carry the gene for either Shiga toxin 1 (Stx1) or Stx2, whereas these genes were present in TT12A and the toxins were produced. Apart from that, both strains carried the +93 gusA mutation, the cluster I ehxA gene for enterohemolysin, and theeae gene for γ-intimin, which are all characteristics of the O157:H7 serotype. Phenotypic assays confirmed that both strains exhibited enterohemolysin activity and the attachment and effacing lesion on HeLa cells. Multilocus enzyme electrophoresis analysis showed that the strains are closely related genetically and belong in the same clonal group. Pulsed-field gel electrophoresis (PFGE) typing ofXbaI-digested genomic DNA revealed that the two strains differed by two bands but shared 90% similarity and clustered in the same clade. All other non-Stx-producing O157:H7 strains examined clustered in a major clade that was distinct from that of Stx-producing O157:H7 strains. The findings that TT12B was identical to TT12A, except for Stx production, and its PFGE profile is also more closely related to that of Stx-producing O157:H7 strains suggest that TT12B was derived from TT12A by the loss of both stx genes.
{"title":"Isogenic Strain of Escherichia coliO157:H7 That Has Lost both Shiga Toxin 1 and 2 Genes","authors":"P. Feng, M. Dey, A. Abe, T. Takeda","doi":"10.1128/CDLI.8.4.711-717.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.711-717.2001","url":null,"abstract":"ABSTRACT An Escherichia coli O157:H7 strain isolated from a patient with hemorrhagic colitis was found to exhibit two slightly different colony morphology types on differential medium. Each morphological type, designated TT12A and TT12B, was isolated, and serological testing using various assays confirmed that both strains carried the O157 and the H7 antigens. Biochemical testing showed that the strains had identical profiles on AP120E analysis and, like typical O157:H7 strains, did not ferment sorbitol or exhibit β-glucuronidase activity. Analysis with a multiplex PCR assay showed that TT12B did not carry the gene for either Shiga toxin 1 (Stx1) or Stx2, whereas these genes were present in TT12A and the toxins were produced. Apart from that, both strains carried the +93 gusA mutation, the cluster I ehxA gene for enterohemolysin, and theeae gene for γ-intimin, which are all characteristics of the O157:H7 serotype. Phenotypic assays confirmed that both strains exhibited enterohemolysin activity and the attachment and effacing lesion on HeLa cells. Multilocus enzyme electrophoresis analysis showed that the strains are closely related genetically and belong in the same clonal group. Pulsed-field gel electrophoresis (PFGE) typing ofXbaI-digested genomic DNA revealed that the two strains differed by two bands but shared 90% similarity and clustered in the same clade. All other non-Stx-producing O157:H7 strains examined clustered in a major clade that was distinct from that of Stx-producing O157:H7 strains. The findings that TT12B was identical to TT12A, except for Stx production, and its PFGE profile is also more closely related to that of Stx-producing O157:H7 strains suggest that TT12B was derived from TT12A by the loss of both stx genes.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"81 1","pages":"711 - 717"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72691131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.762-767.2001
R. D. Waard, Johan Garssen, J. Snel, G. Bokken, T. Sako, J.H.J. Huis in 't Veld, Joseph G. Vos
ABSTRACT In this study, the effects of orally administered viableLactobacillus casei Shirota strain YIT9029 on the immunity parameters of Wistar and Brown Norway rats were examined. For this purpose, we used the Trichinella spiralis host resistance model. Two weeks before and during T. spiralisinfection, rats were fed 109 viable L. casei bacteria 5 days per week. The T. spiralis-specific delayed-type hypersensitivity (DTH) response was significantly enhanced in both Wistar and Brown Norway rats given L. casei. In both rat strains fedL. casei, serum T. spiralis-specific immunoglobulin G2b (IgG2b) concentrations were also significantly increased. In the model, no significant effects ofL. casei on larval counts or inflammatory reactions in the tongue musculature, body weights, or lymphoid organ weights were observed. Serum specific antibody responses, other than IgG2b, were not changed by feeding of L. casei. In contrast toL. casei, it was shown that orally administeredBifidobacterium breve or Bifidobacterium bifidum had no influence on the measured infection and immunity indices in the rat infection model. Since the rat DTH response is considered to be a manifestation of Th1 cell-mediated immunity and the IgG2b isotype has been associated with Th1 activity, it was concluded that Th1 cells could play an active role in the immunomodulatory effects of orally administered L. casei. Furthermore, our data do not indicate that the effect of oral supplementation withL. casei is dependent on the genetic background of the host.
{"title":"Enhanced Antigen-Specific Delayed-Type Hypersensitivity and Immunoglobulin G2b Responses after Oral Administration of ViableLactobacillus casei YIT9029 in Wistar and Brown Norway Rats","authors":"R. D. Waard, Johan Garssen, J. Snel, G. Bokken, T. Sako, J.H.J. Huis in 't Veld, Joseph G. Vos","doi":"10.1128/CDLI.8.4.762-767.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.762-767.2001","url":null,"abstract":"ABSTRACT In this study, the effects of orally administered viableLactobacillus casei Shirota strain YIT9029 on the immunity parameters of Wistar and Brown Norway rats were examined. For this purpose, we used the Trichinella spiralis host resistance model. Two weeks before and during T. spiralisinfection, rats were fed 109 viable L. casei bacteria 5 days per week. The T. spiralis-specific delayed-type hypersensitivity (DTH) response was significantly enhanced in both Wistar and Brown Norway rats given L. casei. In both rat strains fedL. casei, serum T. spiralis-specific immunoglobulin G2b (IgG2b) concentrations were also significantly increased. In the model, no significant effects ofL. casei on larval counts or inflammatory reactions in the tongue musculature, body weights, or lymphoid organ weights were observed. Serum specific antibody responses, other than IgG2b, were not changed by feeding of L. casei. In contrast toL. casei, it was shown that orally administeredBifidobacterium breve or Bifidobacterium bifidum had no influence on the measured infection and immunity indices in the rat infection model. Since the rat DTH response is considered to be a manifestation of Th1 cell-mediated immunity and the IgG2b isotype has been associated with Th1 activity, it was concluded that Th1 cells could play an active role in the immunomodulatory effects of orally administered L. casei. Furthermore, our data do not indicate that the effect of oral supplementation withL. casei is dependent on the genetic background of the host.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"129 1","pages":"762 - 767"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74692241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.772-775.2001
A. Cloeckaert, Sylvie Baucheron, N. Vizcaı́no, M. Zygmunt
ABSTRACT Previously a Brucella protein named CP28, BP26, or Omp28 has been identified as an immunodominant antigen in infected cattle, sheep, goats, and humans. In the present study we evaluated antibody responses of infected and B. melitensisRev.1-vaccinated sheep to the BP26 protein using purified recombinant BP26 protein produced in Escherichia coli in an indirect enzyme-linked immunosorbent assay (I-ELISA). The specificity of the I-ELISA determined with sera from healthy sheep (n = 106) was 93%. The sensitivity of the I-ELISA assessed with sera from naturally infected and suspected sheep found positive in the current conventional diagnostic tests was as follows: 100% for bacteriologically and serologically positive sheep (n = 50), 88% for bacteriologically negative but serologically and delayed-type hypersensitivity-positive sheep (n = 50), and 84% for bacteriologically and serologically negative but delayed-type hypersensitivity-positive sheep (n = 19). However, the absorbance values observed did not reach those observed in an I-ELISA using purified O-polysaccharide (O-PS) as an antigen. In sheep experimentally infected with B. melitensis H38 the antibody response to BP26 was delayed and much weaker than that to O-PS. Nevertheless, the BP26 protein appears to be a good diagnostic antigen to be used in confirmatory tests and for serological differentiation between infected and B. melitensis Rev.1-vaccinated sheep. Weak antibody responses to BP26 in some of the latter sheep suggest that aB. melitensis Rev.1 bp26 gene deletion mutant should be constructed to ensure this differentiation.
{"title":"Use of Recombinant BP26 Protein in Serological Diagnosis of Brucella melitensis Infection in Sheep","authors":"A. Cloeckaert, Sylvie Baucheron, N. Vizcaı́no, M. Zygmunt","doi":"10.1128/CDLI.8.4.772-775.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.772-775.2001","url":null,"abstract":"ABSTRACT Previously a Brucella protein named CP28, BP26, or Omp28 has been identified as an immunodominant antigen in infected cattle, sheep, goats, and humans. In the present study we evaluated antibody responses of infected and B. melitensisRev.1-vaccinated sheep to the BP26 protein using purified recombinant BP26 protein produced in Escherichia coli in an indirect enzyme-linked immunosorbent assay (I-ELISA). The specificity of the I-ELISA determined with sera from healthy sheep (n = 106) was 93%. The sensitivity of the I-ELISA assessed with sera from naturally infected and suspected sheep found positive in the current conventional diagnostic tests was as follows: 100% for bacteriologically and serologically positive sheep (n = 50), 88% for bacteriologically negative but serologically and delayed-type hypersensitivity-positive sheep (n = 50), and 84% for bacteriologically and serologically negative but delayed-type hypersensitivity-positive sheep (n = 19). However, the absorbance values observed did not reach those observed in an I-ELISA using purified O-polysaccharide (O-PS) as an antigen. In sheep experimentally infected with B. melitensis H38 the antibody response to BP26 was delayed and much weaker than that to O-PS. Nevertheless, the BP26 protein appears to be a good diagnostic antigen to be used in confirmatory tests and for serological differentiation between infected and B. melitensis Rev.1-vaccinated sheep. Weak antibody responses to BP26 in some of the latter sheep suggest that aB. melitensis Rev.1 bp26 gene deletion mutant should be constructed to ensure this differentiation.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"2011 1","pages":"772 - 775"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78912397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-07-01DOI: 10.1128/CDLI.8.4.724-730.2001
C. Chappell, John A. Wright, M. Coletta, A. Newsome
ABSTRACT Acanthamoeba species can cause serious, debilitating, and sometimes life-threatening infections. Three groups have been identified using morphological and immunological comparisons. Previous serological studies have utilized a variety of antigen preparations and assay methods and reported disparate (3 to 100%) results. This study was designed to (i) optimize an enzyme-linked immunosorbent assay for detecting serum antibodies to each of the Acanthamoebaserogroups and (ii) test 55 healthy individuals for specific immunoglobulin G reactivity. The highest signal-to-background ratio was found when 3,000 fixed, intact trophozoites per well were used with a 1:10 serum dilution. Sera yielding optical densities of <0.25 against all three Acanthamoeba serogroups were used to define the cutoff for positive results. The highest background reactivity with these sera was seen with Acanthamoeba polyphaga (serogroup 2), followed by Acanthamoeba culbertsoni (serogroup 3) andAcanthamoeba astronyxis (serogroup 1). Of 55 subjects tested, the highest number of positive results was seen with A. polyphaga (81.8%), followed by A. astronyxis(52.8%) and A. culbertsoni (40%). Seven serum samples (12.7%) were negative for all three Acanthamoebaserogroups, 16 (29.1%) were positive for one serogroup only, 16 were positive for two serogroups, and 16 reacted to all three serogroups. Further analysis showed no significant associations between serogroup reactivity and age or gender. However, some ethnic differences were noted, especially with A. polyphaga antigens. In that case, serum samples from Hispanic subjects were 14.5 times less likely to be positive (P = 0.0025) and had lower mean absorbance values (P = 0.047) than those from Caucasian subjects. Overall, these data suggest that Acanthamoeba colonization or infection is more common than previously thought. Mild or asymptomatic infections may contribute to the observed serum reactivities.
{"title":"Standardized Method of MeasuringAcanthamoeba Antibodies in Sera from Healthy Human Subjects","authors":"C. Chappell, John A. Wright, M. Coletta, A. Newsome","doi":"10.1128/CDLI.8.4.724-730.2001","DOIUrl":"https://doi.org/10.1128/CDLI.8.4.724-730.2001","url":null,"abstract":"ABSTRACT Acanthamoeba species can cause serious, debilitating, and sometimes life-threatening infections. Three groups have been identified using morphological and immunological comparisons. Previous serological studies have utilized a variety of antigen preparations and assay methods and reported disparate (3 to 100%) results. This study was designed to (i) optimize an enzyme-linked immunosorbent assay for detecting serum antibodies to each of the Acanthamoebaserogroups and (ii) test 55 healthy individuals for specific immunoglobulin G reactivity. The highest signal-to-background ratio was found when 3,000 fixed, intact trophozoites per well were used with a 1:10 serum dilution. Sera yielding optical densities of <0.25 against all three Acanthamoeba serogroups were used to define the cutoff for positive results. The highest background reactivity with these sera was seen with Acanthamoeba polyphaga (serogroup 2), followed by Acanthamoeba culbertsoni (serogroup 3) andAcanthamoeba astronyxis (serogroup 1). Of 55 subjects tested, the highest number of positive results was seen with A. polyphaga (81.8%), followed by A. astronyxis(52.8%) and A. culbertsoni (40%). Seven serum samples (12.7%) were negative for all three Acanthamoebaserogroups, 16 (29.1%) were positive for one serogroup only, 16 were positive for two serogroups, and 16 reacted to all three serogroups. Further analysis showed no significant associations between serogroup reactivity and age or gender. However, some ethnic differences were noted, especially with A. polyphaga antigens. In that case, serum samples from Hispanic subjects were 14.5 times less likely to be positive (P = 0.0025) and had lower mean absorbance values (P = 0.047) than those from Caucasian subjects. Overall, these data suggest that Acanthamoeba colonization or infection is more common than previously thought. Mild or asymptomatic infections may contribute to the observed serum reactivities.","PeriodicalId":10395,"journal":{"name":"Clinical Diagnostic Laboratory Immunology","volume":"74 1","pages":"724 - 730"},"PeriodicalIF":0.0,"publicationDate":"2001-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90813768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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