Fig. 1

Manual sorting of fixed and immuno- or cytochemically stained cells. (A) Micropipette attached to a mouthpiece for manual cell isolation. The inner diameter of micropipette is 20–50 µm and the tip frame is polished. This micropipette is held by a pipette holder, which is connected to a silicon tube and mouthpiece (200-µL tip filled with cotton). (B) Picture showing cell isolation by a breath-controlled micropipette under a dissecting microscope. (C) Photograph showing HeLa cells after cytochemical staining for alkaline phosphatase (ALP) activity and subsequent cell isolation. As shown in the left upper panel, HeLa cells comprise at least two types of cells, namely extensively ALP-stained cells (arrows) and less stained cells (arrowheads). Twenty microliter of the ALP-stained cell suspension was picked using a 200 µL tip attached to a Gilson Pipette under a dissecting microscope and placed onto a non-adhesive plastic plate. (D) Further processing of cells. A few cells (including ALP-positive and negative cells) are collected using a micropipette and placed onto another 1 µL drop. Finally, a single cell is collected into the pipette. (E) Placing of cell(s) into a tube. The sorted cell(s) are transferred to a 1 µL drop of Ca²⁺, Mg²⁺-free Dulbecco’s modified phosphate-buffered saline containing 4% fetal bovine serum (DPBS-FBS) in a 1.5 mL microtube. The photograph shown in the bottom panel is a single ALP-positive cell after transfer to a 1 µL drop of DPBS-FBS (in the microtube)