*Corresponding author: Juan G Maldonado-Estrada, OHVRI Group, School of Veterinary Medicine, University of Antioquia, Medellín, Colombia, Tel: +57 42199126; E-mail: juan.maldonado@udea.edu.co Citation: Ramírez-Garcia RR, Rojas M, Arboleda-Peña B, Fernandez-Silva JA, Maldonado-Estrada JG (2018) Effect of Dexamethasone, Lipopolysaccharide or Interferon-Gamma on the Recovery of Viable Mycobacterium avium Sub- species paratuberculosis from In Vitro-Infected Primary Bovine Macrophages. J Anim Res Vet Sci 2: 008. Received: October 17, 2018; Accepted: September 06, 2018; Published: Sep- tember 24, 2018 Copyright: © 2018 Ramírez-Garcia RR, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abbreviations JD: Johne’s Disease Map: Mycobecterium avium subspecies paratuberculosis IFN-g: Interferon gamma IL-10: Interleukin 10 TGF-b: Transforming Growth Factor type beta Th1: Type 1 CD4+ T helper cells Th2: Type 2 CD4+ T helper cells CTL: Cytotoxic T cells LAK: Lymphokine-Activated T cells MDM: Monocyte-Derived Macrophages LPS: Lipopolysaccharide IS900: Insertion sequence 900, used as a target for the identifca- tion of Mycobacterium avium subsp. paratuberculosis MoAb: Monoclonal Antibody MOI: Multiplicity of Infection ATCC: American Type Culture Collection PBMC: Peripheral Blood Mononuclear Cells TNF-a: Tumor Necrosis Factor alpha CCL3: CC Chemokine Ligand 3 IP-10: Interferon-induced Protein 10 Mycobactin-j: Iron-chelated substance used as a growth factor for the isolation of Mycobactin-dependent Mycobacterium BCG: Bacillus Calmette-Guérin (vaccine) Introduction Mycobacterium avium subspecies paratuberculosis (Map) caus- es paratuberculosis or Johne’s Disease (JD), which is a chronic Ramírez-Garcia RR, et al., J Anim Res Vet Sci 2018, 2: 008 DOI: 10.24966/ARVS-3751/100008 HSOA Journal of Animal Research and Veterinary Science Research Article Rene Ramirez-Garcia 1,2 , Mauricio Rojas 3 , Beatriz Peña Arboleda 4 , Jorge A. Fernandez-Silva 2 and Juan G. Maldonado-Estrada 5 * 1 Faculty of Veterinary Medicine and Zootechny, University CES, Medellín, Colombia 2 Centauro Group, School of Veterinary Medicine, University of Antioquia, Medellín, Colombia 3 GICIG Group, Faculty of Medicine, University of Antioquia, Medellin, Colombia 4 Reproduction Group, Facultyof Medicine, University of Antioquia, Me- dellín, Colombia 5 OHVRI Group, School of Veterinary Medicine, University of Antioquia. Medellín, Colombia Effect of Dexamethasone, Li- popolysaccharide or Interfer- on-Gamma on the Recovery of Viable Mycobacterium avium Subspecies paratuberculosis from In Vitro-Infected Primary Bovine Macrophages Abstract Study background: The study was designed to evaluate if the addi- tion of Dexamethasone, IFN-g, or LPS into culture media of primary bovine Monocyte-Derived Macrophages (MDMs), could support in vitro infection with Mycobacterium avium subspecies paratubercu- losis. Methods: Primary bovine Monocyte-Derived Macrophages (MDMs) were infected in vitro with a reference strain of Map at 5:1 MOI for 2h. Map-infected MDMs were stimulated with IFN-g, LPS, Dexametha- sone or medium alone for 24h. At 0, 6, 72 and 120h of culture, it was evaluated the presence of Map by bacterial culture and amplifca- tion of the IS900 fragment by real-time PCR. The function of Map-in- fected MDM was evaluated by measurement of TNF-a, IL-6, IL-8, IL-10, IL-12, IP-10, and CCL3 in culture supernatants by Luminex. Data were analyzed by Kruskal-Wall is test. Results: The IS900 segment was amplifed in samples of Map-in- fected MDM from all stimuli. The growth of Map in bacterial cul- ture was observed at each time-point evaluated without statistically signifcant differences between groups. Map-infected-MDMs stim- ulated with Dexamethasone signifcantly reduced cytokine produc- tion compared with control, excepting for IP-10 production from 6 to 120h (P<0.01). Overall cytokine production at 72h was signifcantly higher in Map-infected MDM treated with LPS (P<0.01) excepting for IP-10 and CCL3 production at 120h. IL-8 and IL-12 production at 72h and IP-10 production at 120h were signifcantly higher in Map-infected MDM treated with IFN-g (P<0.01). Conclusion: Primary bovine MDM obtained from peripheral blood mononuclear cells could be used for growth of Map in vitro. The addition of LPS or IFN-gamma reduced the capability of MDM for sustaining the growth of Map until 120h post-infection, although Dexamethasone sustained the recovery of viable Map until 120h in culture. Keywords: Chemokines; Cytokines; Intracellular Pathogens; Monocyte-Derived Macrophages