Preparation of Bone Marrow Sections

It is possible to prepare in the following manner sections of aspirated bone marrow suitable for staining by the majority of conventional methods. The aspirated marrow is ejected into a small test tube containing 0.5 mg heparin powder. At any convenient time during the next hour the material is poured into a watch glass, and the individual marrow particles, free from excess blood, transferred by means of a thin pointed plastic rod to a jar containing 10-15 ml of fixative. Any of the commonly employed fixatives may be used. After not less than 1 hr, the marrow particles are poured onto filter paper from which they are removed to a test tube containing 70% ethanol. During dehydration with absolute ethanol, clearing with two changes of chloroform and embedding in paraffin wax, the particles remain in the tube. After cooling, the tube is broken and the material, found at the apex of the round-ended block, is readily accessible for cutting. Concentration is sufficient to allow the whole sample to be studied in a small number of serial sections. Experience has shown that these sections are equally satisfactory for the study of morphology, cytology, or mineral content.