RT Journal Article
T1 Evaluating the stability of antibody titres against Leishmania infantum determined by IFAT in long-term stored canine frozen samples.
A1 Olmeda, Patricia
A1 Díaz-Regañón Fernández, David Rafael
A1 Villaescusa Fernández, Alejandra
A1 Amusategui, Inmaculada
A1 Tesouro Díez, Miguel Ángel
A1 Rodríguez Franco, Fernando
A1 García-Sancho Téllez, Mercedes Guadalupe
A1 Martín Fraile, Daniel
A1 Sainz Rodríguez, Ángel
AB Abstract Background The immunofluorescence antibody test (IFAT) is a serological diagnostic technique used to quantify serum antibodies generated in response to exposure to various pathogens, such as Leishmania infantum. Retrospec  tive analysis of previously collected frozen samples is highly valuable for clinical and research purposes. The primary aim of this study was to evaluate the impact of long-term frozen storage of canine plasma samples on the IFAT-based serological diagnosis of L. infantum exposure. Methods A total of 189 frozen plasma samples from dogs stored at −20 °C for 5, 10 or 20 years, which had previously been tested for L. infantum exposure via IFAT (IgG), were reanalysed to assess the concordance between past and cur  rent qualitative and quantitative results. Results The qualitative agreement between the former and current IFATs was 92.1%. The samples from 20 years prior presented the greatest increase in negative samples in the second analysis (from 28.6 to 39.7%). A strong positive cor  relation was observed between the quantitative measurements of the past and present across all three groups. The exact quantitative agreement was 48.7%. Conclusions The results of this study indicate that freezing at −20 °C is a good technique for prolonged storage of samples for the detection of L. infantum exposure in dogs, as the qualitative IFAT result is not significantly altered. This finding is of particular interest both for clinical endeavours and for future research in this field.
PB BioMed Central
YR 2025
FD 2025
LK https://hdl.handle.net/20.500.14352/123578
UL https://hdl.handle.net/20.500.14352/123578
LA eng
NO Olmeda, P., Díaz-Regañón, D., Villaescusa, A., Amusategui, I., Tesouro, M. A., Rodríguez-Franco, F., García-Sancho, M., Martín-Fraile, D., & Sainz, Á. (2025). Evaluating the stability of antibody titres against Leishmania infantum determined by IFAT in long-term stored canine frozen samples. Parasites & vectors, 18(1), 327. https://doi.org/10.1186/s13071-025-06982-x
NO Author contributions: P.O. wrote the original draft, analysed the data and wrote, reviewed and edited the manuscript; A.S., A.V. and D.D-R. wrote, reviewed and edited the manuscript; M.G-S. and F.R-F. reviewed and edited the manuscript. A.S. carried out project coordination; M.A.T., I.A., A.S., D.D-R., P.O. and D.M-F. carried out the IFAT; I.A., A.S., D.D-R., P.O. and D.M-F. read and interpreted the IFAT results. All the authors read and approved the final manuscript.
NO Ministerio de Ciencia, Innovación y Universidades.( España)
DS Docta Complutense
RD 23 dic 2025