Neutrophil migration to lymph nodes through lymph and blood in an immune inflammation model.

GORLINO, C; RANOCCHIA, R; MORÓN, G; MALETTO, B; PISTORESI-PALENCIA, MC

Santiago de Chile.

Congreso; Congreso Latinoamericano de Inmunologia; 2009

Sociedad Latinoamericana de Inmunología

NEUTROPHIL MIGRATION TO LYMPH NODES THROUGH LYMPH AND BLOOD IN AN IMMUNE INFLAMMATION MODEL Gorlino, C; Ranocchia, R; Morón, G; Maletto, B; Pistoresi, M.C. CIBICI-CONICET. Facultad de Ciencias Quimicas-UNC, Cordoba, Argentina. We previously showed that when OVA-FITC was injected into the footpad of OVA/CFA immunized mice, the main OVA-FITC+ cells recruited in draining popliteal lymph nodes were neutrophils and this influx was dependent on an antigen-specific response. On the basis of these findings, we investigated if neutrophils can enter into lymph nodes trough afferent lymphatics and blood. Immunofluorescence of lymph node sections of OVA/CFA-immunized mice injected with OVA-FITC showed the presence of neutrophils OVA-FITC+ in the lumen of lymphatic vessels (LYVE-1+) and in the high endothelial venules (MECA-79+). Bone marrow neutrophils incubated with or without immune complexes (anti-OVA rabbit sera plus OVA) were labeled with CFSE and injected in the footpad or vein of OVA/CFA-immunized mice. Neutrophils were only found in draining popliteal lymph nodes of mice injected  with neutrophils incubated with immune complexes (p<0.05) and not in mice injected with neutrophils without immune complexes. In addition, this migration was dependent on inflammatory condition (p<0.01 non-immunized mice vs OVA/CFA immunized mice). In conclusion, these data provide new evidence about the neutrophil trafficking from skin (by lymph vessels) or from blood into lymph nodes in an immune inflammation model.