title: Differential expression of the fractalkine chemokine receptor (CX3CR1) in human monocytes during differentiation.
abstract: Circulating monocytes (Mos) may continuously repopulate macrophage (MAC) or dendritic cell (DC) populations to maintain homeostasis. MACs and DCs are specialized cells that play different and complementary immunological functions. Accordingly, they present distinct migratory properties. Specifically, whereas MACs largely remain in tissues, DCs are capable of migrating from peripheral tissues to lymphoid organs. The aim of this work was to analyze the expression of the fractalkine receptor (CX3CR1) during the monocytic differentiation process. Freshly isolated Mos express high levels of both CX3CR1 mRNA and protein. During the Mo differentiation process, CX3CR1 is downregulated in both DCs and MACs. However, MACs showed significantly higher CX3CR1 expression levels than did DC. We also observed an antagonistic CX3CR1 regulation by interferon (IFN)-γ and interleukin (IL)-4 during MAC activation through the classical and alternative MAC pathways, respectively. IFN-γ inhibited the loss of CX3CR1, but IL-4 induced it. Additionally, we demonstrated an association between CX3CR1 expression and apoptosis prevention by soluble fractalkine (sCX3CL1) in Mos, DCs and MACs. This is the first report demonstrating sequential and differential CX3CR1 modulation during Mo differentiation. Most importantly, we demonstrated a functional link between CX3CR1 expression and cell survival in the presence of sCX3CL1.
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Cecilia Analia
authors.initials: CA
authors.lastname: Panek
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Maria Victoria
authors.initials: MV
authors.lastname: Ramos
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Maria Pilar
authors.initials: MP
authors.lastname: Mejias
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Maria Jimena
authors.initials: MJ
authors.lastname: Abrey-Recalde
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Romina Jimena
authors.initials: RJ
authors.lastname: Fernandez-Brando
authors.affiliation: Laboratorio de Células Presentadoras de Antígeno y Respuesta Inflamatoria, IMEX-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Maria Soledad
authors.initials: MS
authors.lastname: Gori
authors.affiliation: Laboratorio de Células Presentadoras de Antígeno y Respuesta Inflamatoria, IMEX-CONICET, Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Gabriela Verónica
authors.initials: GV
authors.lastname: Salamone
authors.affiliation: Laboratorio de Patogénesis e Inmunología de Procesos Infecciosos, Instituto de Medicina Experimental (IMEX-CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina.
authors.forename: Marina Sandra
authors.initials: MS
authors.lastname: Palermo
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D000073883:CX3C Chemokine Receptor 1; D002454:Cell Differentiation / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003713:Dendritic Cells / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D005786:Gene Expression Regulation; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D015847:Interleukin-4 / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D009000:Monocytes / Q000166:cytology* / Q000187:drug effects / Q000276:immunology; D009928:Organ Specificity; D061251:Primary Cell Culture; D019707:Receptors, Chemokine / Q000235:genetics* / Q000276:immunology; D015398:Signal Transduction
chemical_list: D000073883:CX3C Chemokine Receptor 1; C095235:CX3CR1 protein, human; C508598:IL4 protein, human; D019707:Receptors, Chemokine; D015847:Interleukin-4; D007371:Interferon-gamma