Neospora caninum tachyzoite immunome study reveals differences among three biologically different isolates.
Pathogenesis of bovine neosporosis is determined by different host- and parasite-dependent factors, including isolate virulence. A previous study identified that several Neospora caninum tachyzoite proteins were more abundant in virulent isolates, Nc-Liv and Nc-Spain7, compared with the low-virulent isolate Nc-Spain1H. Herein, we explored differences in the immunomes of these three isolates. Protein extracts from the Nc-Liv, Nc-Spain1H and Nc-Spain7 isolates were analysed in a 3×3 design by 2-DE immunoblot using sera from experimentally infected mice with these same three isolates. All isolates displayed a highly similar antigenic pattern when they were assessed using the same serum. Most of the reactive spots were located in the acidic region (pH 3-7) and grouped in 3 antigenic areas (250-70, 45-37 and 35-15 KDa). Differences found in the immunome depended on the sera used, regardless of the extract employed. In this sense, sera from Nc-Liv and Nc-Spain7 infected mice recognized the highest number of antigens, followed by Nc-Spain1H infected mice sera. In fact, 4 proteins identified by MS were not consistently detected in each isolate extract by sera from low-virulent Nc-Spain1H-infected mice: serine-threonine phosphatase 2C and superoxide dismutase (related to metabolism), gliding associated protein GAP45 (related to tachyzoites invasion), and NcGRA1 (located on dense granules). Similarly, 4 non-identified spots and another 2 spots chains located in 45-37 kDa area were not detected by this pooled sera. Variations between virulent Nc-Spain7 and Nc-Liv were limited to the absence of recognition by sera from Nc-Spain7-infected mice of GAP45 and the spot chains located in the 45-37 kDa area. These results suggest that variations in the immunome profiles rely on the immune response induced by each isolate and that these differentially recognized antigens could be investigated as putative virulence markers of neosporosis.
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain. Electronic address: jregidor@vet.ucm.es.
Javier
J
Regidor-Cerrillo
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Paula
P
García-Lunar
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Iván
I
Pastor-Fernández
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Gema
G
Álvarez-García
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Esther
E
Collantes-Fernández
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Mercedes
M
Gómez-Bautista
SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
Luis M
LM
Ortega-Mora
D000818:Animals; D000953:Antigens, Protozoan; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D018688:Neospora / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry; D014774:Virulence
D000953:Antigens, Protozoan; D015800:Protozoan Proteins
2-DE immunoblot; Immunogenic response pattern; Intra-specific diversity; Neospora caninum; Tachyzoite immunome; Virulence markers