Veterinary Immunology and Immunopathology 163 (2015) 67–76 Contents lists available at ScienceDirect Veterinary Immunology and Immunopathology j ourna l h omepa ge: www.elsevier.com/locate/vetimm Research Paper Transcription of innate immunity genes and cytokine secretion by canine macrophages resistant or susceptible to intracellular survival of Leishmania infantum Andréia Pereira Turchetti a , Luciana Fachini da Costa c , Everton de Lima Romão a , Ricardo Toshio Fujiwara b , Tatiane Alves da Paixão c , Renato Lima Santos a,∗ a Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil b Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil c Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil a r t i c l e i n f o Article history: Received 12 July 2014 Received in revised form 20 September 2014 Accepted 13 November 2014 Keywords: Leishmania infantum Macrophage Dog Innate immunity Cytokines a b s t r a c t In this study we assessed the basal transcription of genes associated with innate immu- nity (i.e. Nramp1, NOD1, NOD2, TLR1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, and TLR9) in canine monocyte-derived macrophages from Leishmania-free dogs. Additionally, secretion of cytokines (IL-10, IL-12, TNF- and IFN-) and nitric oxide in culture supernatants of macrophages with higher or lower resistance to intracellular survival of Leishmania infan- tum was also measured. Constitutive transcription of TLR9 and NOD2 were negligible; NOD1, TLR1, and TLR7 had low levels of transcription, whereas Nramp1 and TLR2, 3, 4, 5, and 6 had higher levels of constitutive transcription in canine monocyte-derived macrophages. There were no significant differences in transcription between macrophages with higher or lower resistance to intracellular survival of L. infantum. Secretion of TNF- was higher in more resistant macrophages (designated as resistant) at 24 h after infection when com- pared to less resistant macrophages (designated as susceptible), as well as the secretion of IFN- at 72 h post infection. Secretion of IL-10 was lower in resistant macrophages at 24 h after infection. No detectable production of nitric oxide was observed. Interestingly, there was a negative correlation between NOD2 transcript levels and intracellular survival of L. infantum in resistant macrophages. This study demonstrated that decreased intracellular survival of L. infantum in canine macrophages was associated with increased production of TNF- and IFN- and decreased production of IL-10; and that constitutive transcription of Nramp1, TLR and NLR does not interfere in intracellular survival of L. infantum. © 2014 Elsevier B.V. All rights reserved. ∗ Corresponding author at: Departamento de Clínica e Cirurgia Vet- erinária, Escola de Veterinária, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos 6627, CEP 30161-970, Belo Horizonte, MG, Brazil. Tel.: +55 31 3409 2239; fax: +55 31 3409 2230. E-mail address: rsantos@vet.ufmg.br (R.L. Santos). 1. Introduction The innate immune system is the first line of defense, programmed to quickly respond in a non-specific manner to structures common to groups of similar organisms, also known as microbe-associated molecular patterns (MAMP). Two of the receptor families responsible for recognizing http://dx.doi.org/10.1016/j.vetimm.2014.11.010 0165-2427/© 2014 Elsevier B.V. All rights reserved.