It means that the amount of calcium carbonate excreted in urine decreased just before the hamsters succumbed to infection. After the seventh day of infection, viable leptospires could be recovered from the urine. Thus, it is suggested that leptospires are not shed from the kidneys until just before death. Most of the urinary proteins detected
in this study were associated with host renal failure such as acute renal transplant rejection [29, 30], glomerular disease [31, 32, 36], diabetes mellitus type 2 [33, 35], chronic kidney disease [34], pancreatitis [31], and endemic nephropathy [37]. The proteins identified in our study, except for leptospiral HADH, are selleck chemical biomarkers known to be involved in renal failure, but are not specific for Leptospira infection. Albumin was the main protein detected in infected hamster urine during the end stage of infection (Figure 2). This is one of the plasma proteins and its primary function
is to maintain the colloidal osmotic pressure this website in both the vascular and extra-vascular spaces. The urine-excreted proteins can serve as markers for glomerular disease [31, 32] and diabetes [33]. selleck Conclusions HADH was detected in urine before the onset of illness in our hamster model of leptospirosis. This is the first study reporting that leptospiral HADH is released in the urine during the infection. Therefore, this protein could be applicable in early diagnostic assays for human leptospirosis. Methods Bacteria Leptospira interrogans serovar Manilae strain K64 that was isolated from the kidneys of a rat in the Philippines [56] was used in this study, and cultured in modified Korthof’s medium supplemented with 10% rabbit serum at 30°C. Prior to experiments, strain K64 was passaged through
hamsters to maintain its virulence. Strain K64 passaged less than ten times in vitro was used for experiments. LD50 of strain K64 was determined by infecting hamsters with serially diluted leptospiral suspension [56, 57]. As a result, the LD50 of K64 strain was 100. Animals Male golden Syrian hamsters (Japan SLC, Inc., Shizuoka, Japan), 4 weeks of age, were injected subcutaneously with Etomidate 103 low-passaged (less than 10× in vitro) leptospires at a final volume of 1 ml Korthof’s medium. As negative controls, animals were injected with Korthof’s medium only. The urine of infected animals was collected by housing them in metabolic chambers for 6 hours daily until they were moribund. Hamster kidneys, livers, spleens, lungs and brains were collected aseptically and squeezed into modified Korthof’s medium containing 5-FU using 5 ml syringe, and incubated at 30°C [56]. Five hundred microliters of culture supernatant was sub-cultured into fresh medium without 5-FU the next day and was kept at 30°C and examined for growth of leptospires daily for one month.