Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Mar 26;12(1):133.
doi: 10.1186/s13071-019-3386-y.

Leishmania infantum-specific IFN-γ production in stimulated blood from cats living in areas where canine leishmaniosis is endemic

Vito Priolo  1 , Pamela Martínez-Orellana  2 , Maria Grazia Pennisi  3 , Marisa Masucci  1 , David Prandi  2 , Dorotea Ippolito  1 , Federica Bruno  4 , Germano Castelli  4 , Laia Solano-Gallego  2
Affiliations

Leishmania infantum-specific IFN-γ production in stimulated blood from cats living in areas where canine leishmaniosis is endemic

Vito Priolo et al. Parasit Vectors. .

Abstract

Background: Feline leishmaniosis caused by Leishmania infantum is considered a rare disease in endemic areas, whereas subclinical infections are common. Immune response plays a key role in driving the course of L. infantum infection in other host species; however, the feline cell-mediated immune response to L. infantum infection has not yet been investigated. The aim of this study was to determine the cell-mediated immune response specific to L. infantum by means of interferon (IFN)-γ release in whole blood assay from cats living in endemic areas (66 in Sicily and 113 in Catalonia) and to compare with antibody levels to L. infantum [enzyme-linked immunosorbent assay (ELISA) and immunofluorescence antibody test (IFAT)], blood parasite load and retroviral infections.

Results: Most cats (n = 140) were L. infantum antibody negative and only 22% (n = 39) were positive. Only 9 and 2% of tested cats had a feline immunodeficency virus (FIV) infection or a feline leukemia virus (FeLV) infection, respectively. Thirty-two cats out of 179 (18%) produced IFN-γ after stimulation with L. infantum soluble antigen (LSA) while the majority of cats (93%) produced IFN-γ after stimulation with concanavalin A (ConA). Six LSA-IFN-γ-producer cats were seropositive (three to ELISA and five to IFAT) but they were polymerase chain reaction (PCR) negative, while only one cat was antibody- and PCR-positive. Significant positive correlations were found between IFN-γ concentrations after stimulation with LSA and ConA, and between serology and PCR testing. No association was found between FIV status and LSA or ConA-IFN-γ production. Combining PCR, serology and specific IFN-γ concentration results, we found that 36% of cats studied were exposed to L. infantum.

Conclusions: As expected, cats from endemic areas produce IFN-γ after ex vivo blood stimulation with LSA and therefore are able to activate a cell-mediated adaptive immune response against the parasite that is variably associated with antibody or blood PCR positivity. The association of this assay to serological and molecular tests provides a better estimate of cat exposure to L. infantum.

Keywords: Adaptive immunity; Feline; Humoral immunity; IFN-γ release whole blood assay; Leishmania infantum; PCR; Retroviral infections.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Percentage of cats positive to L. infantum according respectively to: all specific tests performed, serology (IFAT and/or ELISA) and blood PCR, serology (IFAT and/or ELISA), IFAT, ELISA, blood PCR, and LSA IFN-γ assay
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. World Organization for Animal Health. Leishmaniosis. Manual of diagnostic tests and vaccines for terrestrial animals. 2018. http://www.oie.int/en/international-standard-setting/terrestrial-manual/.... Accessed 05 Mar 2019.
    1. Maroli M, Feliciangeli MD, Bichaud L, Charrel RN, Gradoni L. Phlebotomine sandflies and the spreading of leishmaniases and other diseases of public health concern. Med Vet Entomol. 2013;27:123–147. doi: 10.1111/j.1365-2915.2012.01034.x. - DOI - PubMed
    1. Maroli M, Pennisi MG, Di Muccio T, Khoury C, Gradoni L, Gramiccia M. Infection of sandflies by a cat naturally infected with Leishmania infantum. Vet Parasitol. 2007;45:357–360. doi: 10.1016/j.vetpar.2006.11.009. - DOI - PubMed
    1. Del Río L, Chitimia L, Cubas A, Victoriano I, De la Rúa P, Gerrikagoitia X, et al. Evidence for widespread Leishmania infantum infection among wild carnivores in L. infantum periendemic northern Spain. Prev Vet Med. 2014;113:430–435. doi: 10.1016/j.prevetmed.2013.12.001. - DOI - PubMed
    1. Pennisi MG. Leishmaniosis of companion animals in Europe: an update. Vet Parasitol. 2015;208:35–47. doi: 10.1016/j.vetpar.2014.12.023. - DOI - PubMed

MeSH terms