title: Potential Pitfalls of the Mx1-Cre System: Implications for Experimental Modeling of Normal and Malignant Hematopoiesis.
abstract: Conditional knockout mice are commonly used to study the function of specific genes in hematopoiesis. Different promoters that drive Cre expression have been utilized, with the interferon-inducible Mx1-Cre still being the most commonly used "deleter strain" in experimental hematology. However, different pitfalls associated with this system could lead to misinterpretation in functional studies. We present here two of these issues related to the use of Mx1-Cre: first, a high spontaneous recombination rate when applying commonly used techniques in experimental hematology, and second, undesired short-term consequences of the use of polyinosinic:polycytidylic acid, including changes in cellular phenotypes that, however, resolve within days. Our studies emphasize therefore that proper controls are crucial when modeling gene deletion using the Mx1-Cre transgene.
authors.affiliation: Division of Molecular Medicine and Gene Therapy, Lund Stem Cell Center, Lund University, Lund 22184, Sweden; Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund 22184, Sweden. Electronic address: talia.velasco@med.lu.se.
authors.forename: Talia
authors.initials: T
authors.lastname: Velasco-Hernandez
authors.affiliation: Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund 22184, Sweden.
authors.forename: Petter
authors.initials: P
authors.lastname: Säwén
authors.affiliation: Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund 22184, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Bryder
authors.affiliation: Division of Molecular Medicine and Gene Therapy, Lund Stem Cell Center, Lund University, Lund 22184, Sweden; Division of Molecular Hematology, Lund Stem Cell Center, Lund University, Lund 22184, Sweden; Department of Hematology, Skanes University Hospital, Lund 22184, Sweden; Department of Hematology, Linköping University Hospital, Linköping 58183, Sweden; Department of Clinical and Experimental Medicine, Linköping University, Linköping 58183, Sweden. Electronic address: jorg.cammenga@med.lu.se.
authors.forename: Jörg
authors.initials: J
authors.lastname: Cammenga
mesh_terms: D000818:Animals; D017353:Gene Deletion; D006410:Hematopoiesis / Q000235:genetics*; D019426:Integrases / Q000235:genetics*; D007372:Interferons / Q000235:genetics / Q000378:metabolism; D051379:Mice; D064547:Myxovirus Resistance Proteins / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics; D019076:Transgenes / Q000235:genetics
chemical_list: C579070:Mx1 protein, mouse; D064547:Myxovirus Resistance Proteins; D007372:Interferons; C045073:Cre recombinase; D019426:Integrases