5-HT increases hemocyte incorporation into the niche
(A) After 5-HT treatment of recipient crayfish following adoptive transfer of EdU-labeled hemocytes from donor crayfish, cells containing EdU nuclear labeling (red) are found in the niche (A, Dii, Diii) and proximal stream (A, Eii, Eiii) in recipient crayfish. Cells containing cytoplasmic EdU labeling are also seen in the vicinity of the niche in A (arrowheads above niche).
(B and C) Additional EdU-labeled cells are observed near but not in the niche, some with cytoplasmic EdU (B) and others with nuclear EdU (C); Hoechst and EdU channels are shown separately, with the merged channel on the right. The cell labeling in the niche (D) is illustrated with images of individual fluorescence channels (D, anti-GS; Di, Hoechst; Dii, EdU) and the merged image (Diii). EdU-labeled cells are also observed in the proximal regions of the streams in separate and merged images (A, Eii, Eiii). Scale bars: (A) 30 μm; (B–E) 10 μm.