Pathogenic Leptospira species adapt to a wide range of environmental conditions during disease transmission and infection. While the proteome of in vitro cultivated Leptospira has been characterized in several studies to date, relatively little is known of the proteome as expressed by Leptospira during disease processes. Isolates of Leptospira obtained from patients suffering the severe pulmonary form of leptospirosis cause acute lethal infection in guinea pigs and chronic asymptomatic infection in rats.
View Article and Find Full Text PDFLeptospira interrogans serovar Copenhageni strain RJ16441, a blood isolate from humans with the severe pulmonary form of leptospirosis, has previously been shown to cause fatal pulmonary hemorrhage in guinea pigs and asymptomatic chronic renal tubular colonization with urinary shedding in rats. In this study, RJ16441 caused lethal infection of both C3H/HeJ and C3H/SCID mice, but no hemorrhagic phenomena were observed.
View Article and Find Full Text PDFProtection in experimental rabbit syphilis has been previously assessed by lesion development following intradermal challenge with Treponema pallidum. We have recently reported that passive immunization using monoclonal antibody M131 conveys partial protection as evidenced by significant lesion delays following intradermal challenge. To determine whether such delays in time to lesion appearance corresponded to decreases in the numbers of spirochetes, we used real-time PCR to quantitate T.
View Article and Find Full Text PDFWe have recently shown that a monoclonal antibody, designated M131, that binds a surface phosphorylcholine epitope on Treponema pallidum possesses complement-dependent killing activity and confers partial protection in rabbits following passive immunization (Blanco et al., 2005, Infect. Immun.
View Article and Find Full Text PDFLeptospirosis is the most geographically widespread zoonotic disease in the world. A severe pulmonary form of leptospirosis (SPFL) is being recognized with increased frequency. We have reported that human SPFL isolates of Leptospira cause acute lethal infection with prominent pulmonary hemorrhage in guinea pigs.
View Article and Find Full Text PDFImmunization with purified Treponema pallidum outer membrane vesicles (OMV) has previously resulted in high-titer complement-dependent serum bactericidal activity. In this study, OMV immunization resulted in the isolation of a monoclonal antibody, M131, with complement-dependent killing activity. Passive immunization of rabbits with M131 administered intravenously conferred significant immunity demonstrated by the failure of syphilitic lesions to appear at 29% of intradermal challenge sites (7/24) and a mean delay of approximately 8 days to lesion appearance at the remaining sites (17/24).
View Article and Find Full Text PDFThe severe pulmonary form of leptospirosis (SPFL) is an especially serious and rapid disease process characterized by alveolar hemorrhage and acute respiratory failure. The outer membrane of Leptospira facilitates direct interactions with the environs and likely contains important constituents involved during infection, transmission, survival, and adaptation to environmental conditions, including putative vaccinogen and diagnostic candidates. Outer membrane vesicles (OMVs) were purified by incubation in low-pH citrate buffer, treatment in a French press, and centrifugation over a continuous sucrose gradient.
View Article and Find Full Text PDFThe numbers of host-adapted Borrelia burgdorferi (HAB) organisms in rabbit skin were assessed by real-time PCR over the first 3 weeks of infection. Maximal numbers were found at day 11, while spirochete numbers decreased by more than 30-fold by day 21. The antigenic composition of HAB in skin biopsy samples was determined by use of a procedure termed hydrophobic antigen tissue Triton extraction.
View Article and Find Full Text PDFHuman patients suffering from leptospirosis present with a diverse array of clinical manifestations, including the more severe and often fatal pulmonary form of the disease. The etiology of pulmonary hemorrhage is unclear. Isolates of Leptospira acquired from patients suffering from pulmonary hemorrhage were used to develop a guinea pig model of pulmonary hemorrhage.
View Article and Find Full Text PDFThe general concept that during infection of mice the Borrelia burgdorferi surface protein composition differs profoundly from that of tick-borne or in vitro-cultivated spirochetes is well established. Specific knowledge concerning the differences is limited because the small numbers of spirochetes present in tissue have not been amenable to direct compositional analysis. In this report we describe novel means for studying the antigenic composition of host-adapted Borrelia (HAB).
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