Background： Plasmodium falciparum malaria remains a major life-threatening disease. Recently, the Plasmodium apoptosis-linked pathogenicity factors （PALPF） have been identified. These antigens PALPF are expressed o...Background： Plasmodium falciparum malaria remains a major life-threatening disease. Recently, the Plasmodium apoptosis-linked pathogenicity factors （PALPF） have been identified. These antigens PALPF are expressed only by P falciparum-infected erythrocytes triggering endothelial cell apoptosis （apoptogenic）. Methods： We designed ten synthetic peptides （PI to P10） from PALPF： PF07 0032, PF10_0226, PFI0130c, PFD0875c and MAL13P1.206, and analyzed their antigenicity with an ELISA method using plasma samples from subjects living in Dienga, Gabon. Results： Four peptides showed good reactivity with human antibodies. The prevalence rate of specific IgG was 61%, 51%, 44% and 34% for P5, P6, P4 and P2, respectively. The median optical density of total IgG anti-P2 was higher than that directed against P4 and P6 （P = 0.009; P = 0.012 respectively）. The prevalence rate oflgG subclasses determined with plasma samples recognizing peptide 5 for IgGl, 2, 3 and 4 isotypes was 69%, 45%, 76% and 62%, respectively. All the subjects had at least one immunoglobulin subclass, while 13 （44%） had both IgG1 and IgG3 antibodies. There was no significant difference in the prevalence rate of anti-P5 IgG1, IgG3 and IgG4. Conclusion： These results warrant further immunogenicity studies of peptides 2, 4, 5 and 6 with a view of a tentative to antimalarial vaccine development.展开更多
According to WHO, the rates of smear-negative and extra-pulmonary pulmonary tuberculosis are increasing in high prevalence HIV epidemic areas. Delays in diagnosis of tuberculosis can lead to large excess of mortality....According to WHO, the rates of smear-negative and extra-pulmonary pulmonary tuberculosis are increasing in high prevalence HIV epidemic areas. Delays in diagnosis of tuberculosis can lead to large excess of mortality. It is extremely important to provide a strong diagnosis tool of tuberculosis if we want to reduce mortality due particularly to TB co-infection in HIV infected people in low-income countries such as Togo. This study aims to assess the performance of Determine? TB LAM Antigen, a rapid diagnostic test (RDT) for tuberculosis. It was an evaluation study, conducted at the National Reference Laboratory for Mycobacteria located at the Sylvanus Olympio University Teaching Hospital in Lomé, Togo from 01 July to 15 November 2017. We performed the assessment onto 100 urine specimens collected from 100 subjects (HIV-infected or not). The test allows qualitative detection of the Lipo Arabinno Mannan (LAM) antigen of Mycobacteria in the urine. Bacilloscopy was chosen as gold standard. Overall, the test Determine? TB LAM presented a sensitivity of 31.25% and a specificity of 95%. In contrast, the sensitivity and specificity of the test were respectively 82.35% and 66.67% in the group of HIV-infected subjects. In HIV non-infected subjects, the sensitivity was 17.46% and the specificity was 100%. Determine? TB LAM Antigen test can help detect TB in HIV-infected people unable to expectorate in our settings.展开更多
文摘Background： Plasmodium falciparum malaria remains a major life-threatening disease. Recently, the Plasmodium apoptosis-linked pathogenicity factors （PALPF） have been identified. These antigens PALPF are expressed only by P falciparum-infected erythrocytes triggering endothelial cell apoptosis （apoptogenic）. Methods： We designed ten synthetic peptides （PI to P10） from PALPF： PF07 0032, PF10_0226, PFI0130c, PFD0875c and MAL13P1.206, and analyzed their antigenicity with an ELISA method using plasma samples from subjects living in Dienga, Gabon. Results： Four peptides showed good reactivity with human antibodies. The prevalence rate of specific IgG was 61%, 51%, 44% and 34% for P5, P6, P4 and P2, respectively. The median optical density of total IgG anti-P2 was higher than that directed against P4 and P6 （P = 0.009; P = 0.012 respectively）. The prevalence rate oflgG subclasses determined with plasma samples recognizing peptide 5 for IgGl, 2, 3 and 4 isotypes was 69%, 45%, 76% and 62%, respectively. All the subjects had at least one immunoglobulin subclass, while 13 （44%） had both IgG1 and IgG3 antibodies. There was no significant difference in the prevalence rate of anti-P5 IgG1, IgG3 and IgG4. Conclusion： These results warrant further immunogenicity studies of peptides 2, 4, 5 and 6 with a view of a tentative to antimalarial vaccine development.
文摘According to WHO, the rates of smear-negative and extra-pulmonary pulmonary tuberculosis are increasing in high prevalence HIV epidemic areas. Delays in diagnosis of tuberculosis can lead to large excess of mortality. It is extremely important to provide a strong diagnosis tool of tuberculosis if we want to reduce mortality due particularly to TB co-infection in HIV infected people in low-income countries such as Togo. This study aims to assess the performance of Determine? TB LAM Antigen, a rapid diagnostic test (RDT) for tuberculosis. It was an evaluation study, conducted at the National Reference Laboratory for Mycobacteria located at the Sylvanus Olympio University Teaching Hospital in Lomé, Togo from 01 July to 15 November 2017. We performed the assessment onto 100 urine specimens collected from 100 subjects (HIV-infected or not). The test allows qualitative detection of the Lipo Arabinno Mannan (LAM) antigen of Mycobacteria in the urine. Bacilloscopy was chosen as gold standard. Overall, the test Determine? TB LAM presented a sensitivity of 31.25% and a specificity of 95%. In contrast, the sensitivity and specificity of the test were respectively 82.35% and 66.67% in the group of HIV-infected subjects. In HIV non-infected subjects, the sensitivity was 17.46% and the specificity was 100%. Determine? TB LAM Antigen test can help detect TB in HIV-infected people unable to expectorate in our settings.
