title: Neutrophils promote 6-sulfo LacNAc+ dendritic cell (slanDC) survival.
abstract: There is increasing evidence supporting the notion that neutrophils and other leukocytes establish cooperative actions in regulating innate and adaptive immune responses. In such a context, we have shown recently that human neutrophils amplify NK cell/slanDC-mediated cytokine production by directly costimulating IFN-γ production by NK cells, as well as by potentiating IL-12p70 release by slanDCs via CD18/ICAM-1 interactions. To gain more insights into the molecular bases of the neutrophil-mediated cytokine potentiation by NK cells and slanDCs under coculture conditions, we now report that neutrophils efficaciously maintain slanDC survival by contact-dependent mechanisms. Such a phenomenon occurs in the absence or presence of NK cells, which, in the presence of LPS and IL-2 or the IL-15/IL-18 combination, accelerates slanDC apoptosis significantly. Noteworthy, αICAM-1- and αCD18-neutralizing antibodies, previously shown to suppress IL-12p70 production by slanDCs and consequently, IFN-γ by NK cells under similar experimental conditions, did not minimally alter the neutrophil-mediated prosurvival effect on slanDCs. Altogether, data not only expand our knowledge on the interactions between human neutrophils and slanDCs but also prove that neutrophil-mediated promotion of slanDC survival and potentiation of slanDC-derived IL-12p70 occur via different mechanisms.
authors.affiliation: 1.Division of General Pathology, University of Verona, Strada Le Grazie 8, 37134 Verona, Italy. marco.cassatella@univr.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Micheletti
authors.forename: Claudio
authors.initials: C
authors.lastname: Costantini
authors.forename: Federica
authors.initials: F
authors.lastname: Calzetti
authors.forename: Deseada
authors.initials: D
authors.lastname: Camuesco
authors.forename: Sara
authors.initials: S
authors.lastname: Costa
authors.forename: Nicola
authors.initials: N
authors.lastname: Tamassia
authors.forename: Marco A
authors.initials: MA
authors.lastname: Cassatella
mesh_terms: D000606:Amino Sugars / Q000378:metabolism*; D018821:CD18 Antigens / Q000378:metabolism; D002470:Cell Survival; D019610:Cytoprotection; D003713:Dendritic Cells / Q000166:cytology* / Q000378:metabolism*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D009504:Neutrophils / Q000166:cytology*
chemical_list: C467438:6-sulfo-LacNac; D000606:Amino Sugars; D018821:CD18 Antigens; D018799:Intercellular Adhesion Molecule-1
keywords: IL-15/IL-18; LPS; NK cells