Migration of polymorphonuclear leukocytes by dendritic cells

SCIMONE ML; LUTZKY VP; ZITTERMANN S; MAFFIA PC; JANCIC CC; BUZZOLA FR; ISSEKUTZ A; CHULUYAN HE

IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2005 vol. 114 p. 375 - 385

0019-2805

Dendritic cells (DCs) are the most potent antigen-presenting cells andpopulate many tissues where they may participate in inflammatory reac-tions. The infiltration of polymorphonuclear leucocytes (PMNLs) into tis-sues is a prominent feature of inflammation. The mechanisms of PMNLrecruitment depend on chemotactic factors and adhesion moleculesexpressed on endothelial cells. The aim of the present study was to deter-mine whether DCs participate in the early recruitment of PMNLs. Dend-ritic cells derived from peripheral blood monocytes were used for thisstudy. PMNLs incubated with culture supernatant (CS) from untreated orfrom tumour necrosis factor-a (TNF-a)-treated (1 hr, 100 U/ml, 37)monocyte-derived DCs (moDCs) had increased surface expression of bothCD11b and CD18. Moreover, both untreated and TNF-a-treated moDCsinduced PMNL chemotaxis. By blocking CXCL8, CXCL5, CXCL7 and PanGRO (CXCL1, CXCL2, CXCL3), we observed that CXCL8/interleukin-8might be the chemokine that induced the PMNL chemotactic activity inthe CS of untreated and TNF-a-treated moDC. Furthermore, we investi-gated the regulation of CXCL8 production in moDCs by adhesion mole-cule engagement. Our data demonstrated that CD31, CD18, CD29 andCD49d participated in the adhesion of immature moDCs to endothelium.Moreover, engagement of domains 1–3 of CD31, but not of CD29 orCD18, decreased the production of CXCL8 by immature but not maturemoDCs (which display lower CD31 levels than immature moDCs). Over-all, these results suggest that DCs not only trigger a specific immuneresponse, but also the innate immune response by recruiting PMNLs. Fur-thermore, our results also suggest that CXCL8 production by immatureDCs might be regulated by signalling through CD31 during their migra-tion through the vascular endothelium