Atomic force microscopy to study direct neurite-mast cell (RBL) communication in vitro

Communication between nerves and mast cells is a prototypic demonstration o f neuroimmune interaction. We used an in vitro co-culture approach comprisi ng cultured murine superior cervical ganglia (SCG) and I-at basophilic leuk emia (RBL-2H3) cells. Atomic force microscopy (AFM) showed how neurites att ached to a pseudopodium or a cell body of an RBL cell. After stimulation of SCG neurites with bradykinin or scorpion venom, RBL cells attached to neur ites spread and flattened, and several discharged granules (0.5-1.0 mum in diameter) were found on the surface of the RBL cells. A neurokinin (NK)-1 r eceptor (i.e. substance P receptor) antagonist prevented the RBL degranulat ion. The results showed that activation of the SCG neurites with bradykinin or scorpion venom was able to elicit degranulation in RBL cells which were attached to neurites. (C) 2000 Elsevier Science B.V. All rights reserved.