p55 tumour necrosis factor receptors distribution in neuroblastoma cells

p55 tumour necrosis factor receptors in neuroblastoma SKNBE cells were localized by immunofluorescence microscopy. They were detected at the surface on nonpermeabilized cells and, after differential permeabilization, in the Golgi area as diffuse staining and in the perinuclear region as clusters and punctuations. Intracytoplasmic punctuate forms were detected after permeabilization with Triton X-100, suggesting their location within organelles. Treatment with the differentiation-inducing agent all-trans retinoic acid (RA) greatly increased the cellular density of the immunoreactive receptors and receptors were detected in the newly formed neurites, suggesting that RA promoted their transport from the cell body. The results suggest direct influences on neuronal functions of tumour necrosis factor ct released from adjacent or from target cells.