RT Journal Article T1 Neospora caninum tachyzoite immunome study reveals differences among three biologically different isolates A1 Regidor-Cerrillo, Javier A1 García-Lunar, Paula A1 Ortega Mora, Luis Miguel A1 Gómez Bautista, Mercedes A1 Collantes Fernández, Esther A1 Álvarez García, Gema A1 Pastor Fernández, Iván AB 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. PB Elsevier SN 0304-4017 YR 2015 FD 2015 LK https://hdl.handle.net/20.500.14352/96274 UL https://hdl.handle.net/20.500.14352/96274 LA eng NO Comunidad de Madrid NO Ministerio de Educación, Cultura y Deporte (España) NO Ministerio de Economía y Competitividad (España) DS Docta Complutense RD 12 abr 2025