Gibco serum free dme medium

All spreads were made from testes collected from adult 35-day-old mice. Briefly, testes were decapsulated, finely chopped and rinsed in 1 ml of GIBCO serum-free DME medium (Life Technologies, Carlsbad, CA, USA) containing 1× Complete Protease Inhibitor (Roche, Basel, Switzerland). Six microliters of GIBCO serum-free DME medium (Life Technologies) was then added and tubes were allowed to stand on ice for 5 min to allow large clumps and cellular debris to settle. Six microliters of the remaining supernatant from each sample was subsequently aliquoted into Eppendorf tubes, with each tube containing 1 ml of suspension. Tubes were then centrifuged for 5 min at 5 000 g to pellet the cell suspension. The pellet was then resuspended in 0.1 m sucrose and applied onto glass slides prewetted with 1% paraformaldehyde and 0.1% Triton X-100 in phosphate-buffered saline (PBS). Cells were fixed on the glass slides and air-dried for 3 h at room temperature. The slides were subsequently washed with 1:250 Kodak Photo-Flo 200 (Kodak Professional, Rochester, NY, USA) in 1× PBS and air-dried for 1 h. Once dried, spreads were stored at −80 °C.