If this is correct, the organization of the pores of the ampullary neurons around the bases of the ciliary tuft cells (as revealed by our anti-tubulin labeling) may be important.
A final observation about labeling of ampullary neuron cilia with a tubulin antibody is that the apical canals and pores of these neurons remain closely grouped around the ciliary tuft cells throughout planktotrophic larval development.
Smyth et al., "Intestinal epithelial tuft cells initiate type 2 mucosal immunity to helminth parasites," Nature, vol.
Jay, "Intestinal tuft cells: epithelial sentinels linking luminal cues to the immune system," Mucosal Immunology, vol.
As shown in Figures 2A and 3A, the apical tuft cells constitute three of the four apical pole cells of pretorsional veligers of T.
Figure 5A shows the protruding apices of the two lateral ciliary tuft cells in a larva fixed at 90 h postfertilization, which is after the three large cells that produce the apical ciliary tuft have disappeared.
They both have the same number and major types of cells: four ampullary cells, three para-ampullary cells, and two ciliary tuft cells
. The only notable difference is that the cell bodies and apical projections of the ciliary tuft cells
are ventral to the other cells in the AG of Aplysia, but they seem to occupy a dorsal position in Rostanga (Chia and Koss, 1984).