May grunwald solution 1

Bone marrow preparation was performed according to published methods (Romagna and Staniforth 1989 (link); Salamone et al. 1980 (link)). The soft tissue was removed from the femora and the epiphyses were cut off. The bone marrow was rinsed off the diaphyses with approximately 3 mL 37 °C-warm fetal calf serum (FCS) (Biochrom, Berlin, Germany) per femur, placed on the above-described cellulose column and eluted with 3 mL of Hank's Balanced Salt Solution (HBSS) (Biochrom, Berlin, Germany) (with Ca²⁺ und Mg²⁺). The eluate was centrifuged at 300 g for 5 min and the pellet was suspended in 50 mL FCS. From this suspension three portions per femur were individually placed on slides, air-dried and then stained for 4 min in May-Grunwald solution 1 (Merck, Darmstadt, Germany), followed by 4 min in May–Grunwald solution 2 (May-Grunwald solution 1 diluted 1:1 with aqua bidest.), rinsed in aqua bidest and then stained with Giemsa solution (7.5% dilution derived from Giemsa obtained from Merck, Darmstadt, Germany) for 15 min. Subsequently, the slides were washed twice with aqua bidest, then dried, cleared in xylene and covered with Corbit-Balsam (I. Hecht, Kiel-Hasse, Germany).