ABSTRACT
Se estudió un lote de 28 sueros de llama (Lama gama) de la provincia de Jujuy, Argentina, a fin de identificar antígenos inmunorreactivos contra Leptospira interrogans. Se utilizaron distintas preparaciones antigénicas de la bacteria para estudiar la inmunorreactividad mediante microaglutinación (MAT), ELISA y Western inmunoblot. Un pool de sueros bovinos positivos a la MAT fue empleado como control. Todos los sueros de llama fueron negativos mediante MAT e igual resultado se observó mediante ELISA. Dos de los 28 sueros de llama y el pool de sueros bovinos positivos, al ser evaluados por Western inmunoblot, arrojaron resultados positivos y permitieron identificar proteínas inmunorreactivas. Por MALDI-TOF se logró establecer que la proteína asociada a los dos sueros de llama inmunorreactivos era una flagelina periplásmica de Leptospira interrogans serovar Lai STR, mientras que la asociada al pool de sueros bovinos positivos a Leptospira sp. se trataba de una lipoproteína de la membrana externa de Leptospira interrogans serovar Ballum, LipL21. Estas proteínas podrían ser utilizadas en el diseño de un nuevo ELISA aplicado al diagnóstico temprano de leptospirosis, ya sea en distintos tipos de ganado como así también en reservorios silvestres.
A batch of 28 llama (Lama gama) sera from Jujuy province in Argentina was studied in order to identify immune reactive antigens to Leptospira interrogans. Different antigenic preparations from the bacterium were used to study the immune reactivity by the microagglutinattion (MAT), ELISA and Western immunoblot tests. A control pool of positive bovine sera was used. All the llama sera were negative to MAT as well as to ELISA. Two of the llama sera and the positive bovine sera pool rendered positive results when evaluated by Western immunoblot, allowing the identification of immune reactive proteins. These proteins were identified by MALDI-TOF. A periplasmic flagellin of Leptospira interrogans serovar Lai STR called FlaB1 was identified from the reactive llama sera, and an external membrane lipoprotein of Leptospira interrogans serovar Ballum called LipL21 was identified from the pool of bovine positive sera. These proteins could be used in a new ELISA applied to the early diagnosis of leptospirosis in different kind of cattle or wild reservoirs.
Subject(s)
Animals , Cattle , Antibodies, Bacterial/immunology , Antigens, Bacterial/immunology , Bacterial Outer Membrane Proteins/immunology , Bacterial Proteins/immunology , Camelids, New World/immunology , Epitopes/immunology , Flagellin/immunology , Leptospira interrogans/immunology , Leptospirosis/veterinary , Lipoproteins/immunology , Antigens, Bacterial/isolation & purification , Argentina/epidemiology , Blotting, Western , Bacterial Outer Membrane Proteins/isolation & purification , Bacterial Proteins/isolation & purification , Camelids, New World/blood , Enzyme-Linked Immunosorbent Assay , Epitopes/isolation & purification , Flagellin/isolation & purification , Leptospirosis/epidemiology , Leptospirosis/immunology , Lipoproteins/isolation & purification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Serologic Tests/veterinaryABSTRACT
Kinetics of the humoral immune primary response and seven-day secondary response of adult CF1 mice to FMDV O1 Campos adjuvanted in aluminium hydroxide-saponin (AHS) or in oil emulsion (OE) were evaluated by means of ELISA and passive hemagglutination (PH). Analysis of the response to AHS vaccine showed that ELISA measured maximal titres of primary response at 23 days post-vaccination (dpv), and at day 17 of secondary response, while PH detected maximal titres for primary as well as secondary response around day 60 pv. Mice immunized with OE vaccine studied by ELISA presented a plateau of primary response around 40 dpv, while secondary response was maximal around 80 dpv. The same sera tested by PH showed the highest titres for primary response on day 50 pv and secondary response was maximal on day 40 pv. A criterion for the evaluation of vaccination efficiency in the murine model is proposed based on the methods employed in the determination of antibody level.
ABSTRACT
Kinetics of the humoral immune primary response and seven-day secondary response of adult CF1 mice to FMDV O1 Campos adjuvanted in aluminium hydroxide-saponin (AHS) or in oil emulsion (OE) were evaluated by means of ELISA and passive hemagglutination (PH). Analysis of the response to AHS vaccine showed that ELISA measured maximal titres of primary response at 23 days post-vaccination (dpv), and at day 17 of secondary response, while PH detected maximal titres for primary as well as secondary response around day 60 pv. Mice immunized with OE vaccine studied by ELISA presented a plateau of primary response around 40 dpv, while secondary response was maximal around 80 dpv. The same sera tested by PH showed the highest titres for primary response on day 50 pv and secondary response was maximal on day 40 pv. A criterion for the evaluation of vaccination efficiency in the murine model is proposed based on the methods employed in the determination of antibody level.
ABSTRACT
Un hexadecapéptido correspondiente a la secuencia 144-159 de la proteína estructural VP1 del virus de la fiebre aftosa (CFA), cepa O1K, fue sintetizado por métodos químicos. El mismo, acoplado covalentemente a distintas proteínas portadoras, demostró su capacidad de inducir anticuerpos neutralizantes del VFA cepa O1 Campos (O1Ca) en ratones adultos. La protección fue del 100% cuando se lo acopló a la hemocianina de un molusco (KLH) y fue inoculado en cantidad de 60 microng, dividida en dos dosis y adyuvada con mezcla oleosa. Las proteínas utilizadas como portadoras: albúmina bovina, purificado proteico de Mycobacterium (PPD), gliadina y células de Brocelas produjeron una respuesta inmune menor que la KLH