title: The interactions and essential effects of intrinsic insulin-like growth factor-I on Leishmania (Leishmania) major growth within macrophages.
abstract: Previously, we showed in Leishmania infections that extrinsic insulin-like growth factor (IGF)-I favored Leishmania proliferation and leishmaniasis development. In this study, the interaction of intrinsically expressed IGF-I and Leishmania (Leishmania) major in macrophages was addressed, and a key finding was the observation, using confocal microscopy, of the co-localization of IGF-I and parasites within macrophages. Following stimulation with interferon-γ (IFN-γ), which is known to inhibit IGF-I production in macrophages, we observed a reduction in the expression of both IGF-I mRNA and protein. This reduced expression was accompanied by a reduction in the cellular parasite load that was completely recovered with the addition of extrinsic IGF-I, which suggests an essential role for IGF-I in Leishmania growth.
authors.affiliation: Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, IMTSP-USP, São Paulo, Brazil.
authors.forename: L C
authors.initials: LC
authors.lastname: Reis
authors.forename: E M
authors.initials: EM
authors.lastname: Ramos-Sanchez
authors.forename: H
authors.initials: H
authors.lastname: Goto
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D007371:Interferon-gamma / Q000276:immunology; D018320:Leishmania major / Q000254:growth & development* / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism* / Q000469:parasitology*; D051379:Mice; D018613:Microscopy, Confocal; D059208:Parasite Load; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D012333:RNA, Messenger; D011994:Recombinant Proteins; C519530:insulin-like growth factor-1, mouse; D007334:Insulin-Like Growth Factor I; D007371:Interferon-gamma
keywords: Interferon-γ; Leishmania (Leishmania) major; confocal microscopy; insulin-like growth factor-I; macrophage