ABSTRACT
Serum samples obtained from patients hospitalized in Barbados with severe leptospirosis were tested by the microscopic agglutination test (MAT), enzyme immunoassay (EIA) and immunoblotting with leptospires that had been isolated from these patients. While serum samples taken a few days after onset of symptoms often showed no apparent correlation between MAT and EIA, later sequential serum samples produced similar profiles in both tests during the course of infection. Immunoblotting sonicate from Leptospira interrogans serovars arborea, copenhageni and bim with patients' sera, revealed reactions with a number of bands that corresponded with outer envelope components. These components included lipopolysaccharide (LPS), flagella and other outer membrane proteins, in addition to a low-molecular-weight (MW) carbohydrate cross-reactive with members of the Leptospiraceae. IgM antibodies elicited in the first to second week after infection reacted mainly with LPS and the low-MW cross-reactive carbohydrate. Comparative analysis of isolates of the same serovar by sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting showed that while two serovar arborea isolates were identical, serovar bim isolates differed significantly from each other. This difference was also observed in comparative MAT testing.
Subject(s)
Antibodies, Bacterial/biosynthesis , Antigens, Bacterial/immunology , Leptospira interrogans/immunology , Weil Disease/immunology , Agglutination Tests , Bacterial Outer Membrane Proteins/immunology , Bacterial Proteins/analysis , Bacterial Proteins/immunology , Barbados , Cross Reactions , Electrophoresis, Polyacrylamide Gel , Humans , Immunoblotting , Immunoenzyme Techniques , Immunoglobulin G/biosynthesis , Immunoglobulin M/biosynthesis , Leptospira interrogans/analysis , Lipopolysaccharides/analysisABSTRACT
Acredtita-se que as lesöes teciduais na leptospirose possam decorrer da açäo direta das leptospiras, de toxinas sintetizadas ou liberadas durante sua lise. O presente estudo visou a extraçäo química da glicolipoproteína (GLP) da aleptospira, a produçäo de anti-soro anti-GLP e a avaliaçäo de sua distribuiçäo em cortes de fígado e rim de cobaias inoculadas e sacrificadas em estudo sequencial diário até o 6§ dia de infecçäo, correspondente ao pico da doença. Procurou-se também correlacionar a expressäo tecidual da GLP com o grau de lesöes locais, em busca de novos subsídios para a compreensäo da patogenia da leptospiros. A GLP foi detectada em fígado e rim de 2 dentre 6 cobaias no 5§ dia e em todas as 6 no 6§ dia de infecçäo, sob a forma de grânulos no citoplasma de macrófagos, livres no interstício ou acolados à membrana de células endoteliais e parenquimatosas, especialmente nas regiöes mais lesadas. A cronologia do aparecimento da GLP e sua distribuiçäo sugerem tratar-se de produto de lise de leptospiras fagocitadas por macrófagos e que esta substância, conquanto näo comprovada como iniciadora das lesöes, asocia-se a seu agravamento nas etapas mais avançadas da leptospirose
Subject(s)
Animals , Guinea Pigs , Weil Disease/etiology , Glycoproteins/toxicity , Leptospira interrogans/analysis , Bacterial Proteins/toxicity , Liver/analysis , Glycoproteins/analysis , Kidney/analysis , Bacterial Proteins/analysisABSTRACT
Tissue damage in leptospirosis has been ascribed to direct effect of the microorganisms and/or their virulence, including products synthetized by leptospires or released during their lysis. This study aimed at chemical extraction of the glycolipoprotein (GLP) from virulent leptospires, production of a rabbit anti-GLP and analysis of its distribution in liver and kidney of inoculated guinea-pigs, sacrificed sequentially from the 1st to 6th day of infection, covering the whole, spectrum of acute leptospirosis. The comparison of GLP expression to local injuries aimed at new pathogenetic data. GLP was detected in liver and kidney in 2 out of 6 guinea-pigs on the 5th day and in all 6 animals on the 6th day of infection. Granular forms were seen in the cytoplasm of macrophages, free in interstitium or adhered to endothelial and parenchymal cell membranes, especially in the most damaged sites. These findings lead us to the hypothesis of GLP as a toxic factor resulting from leptospiral lysis by macrophages. Although it was not proved as a promoter of initial lesions, it seems to be related to the enhancement of tissue damage late in the course of the disease.