Project description:Leptospirosis is the most widespread zoonotic disease in the world. The lack of an adequate laboratory test is a major barrier for the diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Leptospira interrogans proteome and investigated the IgG response against leptospiral antigens from 274 individuals, including 80 acute-, 80 convalescent-phase patients and 114 healthy control subjects from regions with endemic, high endemic and no endemic transmission of leptospirosis. A nitrocellulose line blot assay was performed to validate the accuracy of the protein microarray results. We found 16 antigens that can discriminate between acute cases and healthy individuals from a region with high endemic transmission of leptospirosis, and 18 antigens that distinguish convalescent cases. Some of the antigens identified in this study, such as LipL32, the non-identical domains of the Lig proteins, GroEL and Loa22 are already known to be recognized by sera from human patients, thus serving as a proof-of-concept for the serodiagnostic antigen discovery approach. Several novel antigens were identified, including the hypothetical protein LIC10215 which showed good sensitivity and specificity rates for both acute- and convalescent-phase patients. Our study is the first large-scale evaluation of immunodominant antigens associated with naturally acquired leptospiral infection and novel as well as known serodiagnostic leptospiral antigens that are recognized by antibodies in the sera of leptospirosis cases were identified. The novel antigens identified here may have potential use in both the development of new tests and the improvement of currently available assays for diagnosing this neglected tropical disease. Further research is needed to assess the accuracy of these antigens in more appropriate diagnostic platforms. Antibody profiling was peformed on sera from infected and non-infected subjects to investigate the IgG response against leptospiral antigens. These samples comprised 80 acute-, 80 convalescent-phase patients and 114 healthy control subjects, including 29 subjects from United States (non-endemic area), 35 blood donors from Salvador/Brazil (endemic area) and 50 healthy individuals from region with high endemicity of leptospirosis.
Project description:Background The mysterious chronic kidney disease is multifactorial causes. One of the risk factors is leptospirosis, a re-emerging infectious disease caused by Leptospira spp., for endemic leptospirosis tend to coincide with high-incidence regions of chronic kidney disease of unknown etiology. This study aims to investigate the role of leptospirosis as an emerging culprit in which chronic subclinical kidney injury, may predispose to progressive kidney disease when superimposed on secondary nephrotoxic injury. Methods Adenine-induced renal injury in chronic leptospira-infected C57/BL6 mice were studied for evaluating the renal function, histology and gene expression changes. We employed RNA sequencing-based renal transcriptome to investigate pathogenic pathways associated with secondary nephrotoxic injury in chronic kidney injury due to leptospirosis. Results The severity of kidney lesions was increased and the expression of immune/inflammation/fibrosis genes were significantly up-regulated in either low-dose (0.1%) and high-dose (0.2%) adenine-induced renal injury superimposed on infected mice. Whole renal transcriptome analysis reveals that the substantial amplification of the tremendous amount of expressed genes and fibrosis-related pathways was found in adenine-induced kidney injury add-on to leptospira-infected mice which correlated with kidney dysfunction and fibrosis compared to infection or adenine itself. A total of 41 differentially expressed genes associated with fibrosis were identified in infected mice fed with adenine, suggesting that these potential genes contributed to aggravated renal progression occurred in adenine-fed chronic leptospira-infected mice. Conclusions In summary, this study indicates that chronic subclinical kidney infection when exposed to different degree of secondary nephrotoxic injury may predispose to exacerbated and progressive chronic kidney disease.
Project description:Leptospirosis is a re-emerging zoonosis, a globally important infectious disease, caused by an infection with the genus Leptospira. Leptospirosis is associated with acute kidney injury and progress to CKD due to sustained tubulointerstitial inflammation. Macrophages play a critical role in controlling the bacterial burden and tissue inflammation during the spirochete infections. To understand the molecular mechanisms of leptospia-induced macrophage activation and its role in the inflammatory process, we performed the transcriptome profiles of murine bone marrow-derived macrophages infected with pathogenic and non-pathogenuc Leptospira spp.at a multiplicity of infection of 100 for 2 and 24 hrs, respectively.
Project description:The overall goal of these experiments was to determine how human endothelial cells respond to pathogenic Leptospira interrogans. Leptospira interrogans causes leptospirosis, the most widespread zoonotic infection in the world. A hallmark of leptospirosis is widespread endothelial damage, which in severe cases leads to hemorrhage. In these experiments, we infected two endothelial cell lines with pathogenic Leptospira interrogans serovar Canicola strain Ca12-005, and as controls, with the non-pathogenic Leptospira biflexa serovar Patoc strain Pfra. As additional controls, uninfected cells were also included in the analyses.
Project description:The overall goal of these experiments was to determine how human endothelial cells respond to pathogenic Leptospira interrogans. Leptospira interrogans causes leptospirosis, the most widespread zoonotic infection in the world. A hallmark of leptospirosis is widespread endothelial damage, which in severe cases leads to hemorrhage. In these experiments, we infected two endothelial cell lines with pathogenic Leptospira interrogans serovar Canicola strain Ca12-005, and as controls, with the non-pathogenic Leptospira biflexa serovar Patoc strain Pfra. As additional controls, uninfected cells were also included in the analyses.
Project description:Global endemic infections, such as leptospirosis, rickettsial diseases, and dengue infections present diagnostic challenges, posing a dilemma for antibiotic stewardship worldwide. The goal of this project was to identify accurate transcriptional classifiers able to discriminate between bacterial and viral illness of global pathogens.
Project description:Leptospirosis is the most widespread zoonotic disease in the world. The lack of an adequate laboratory test is a major barrier for the diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Leptospira interrogans proteome and investigated the IgG response against leptospiral antigens from 274 individuals, including 80 acute-, 80 convalescent-phase patients and 114 healthy control subjects from regions with endemic, high endemic and no endemic transmission of leptospirosis. A nitrocellulose line blot assay was performed to validate the accuracy of the protein microarray results. We found 16 antigens that can discriminate between acute cases and healthy individuals from a region with high endemic transmission of leptospirosis, and 18 antigens that distinguish convalescent cases. Some of the antigens identified in this study, such as LipL32, the non-identical domains of the Lig proteins, GroEL and Loa22 are already known to be recognized by sera from human patients, thus serving as a proof-of-concept for the serodiagnostic antigen discovery approach. Several novel antigens were identified, including the hypothetical protein LIC10215 which showed good sensitivity and specificity rates for both acute- and convalescent-phase patients. Our study is the first large-scale evaluation of immunodominant antigens associated with naturally acquired leptospiral infection and novel as well as known serodiagnostic leptospiral antigens that are recognized by antibodies in the sera of leptospirosis cases were identified. The novel antigens identified here may have potential use in both the development of new tests and the improvement of currently available assays for diagnosing this neglected tropical disease. Further research is needed to assess the accuracy of these antigens in more appropriate diagnostic platforms.
Project description:Leptospirosis is a neglected zoonotic disease of global importance. Despite its prevalence, pathogenesis is still poorly understood. Our aim was to discover transcripts responsable for pathogenicity of leptospirosis. We compared the transcriptome profiles of saprophyte, attenuated and virulent strain of Leptospira spp.
Project description:Leptospira, the causative agent of leptospirosis is known to have several proteases with potential to degrade extracellular matrix. However, a multipronged approach to identify, classify, characterize and elucidate their role has not been attempted. In this study, we carried out in-depth proteomic analysis of Triton X-114 fractions of Leptospira interrogans using high-resolution LC-MS/MS.