STUDIES ON CHARCOT-LEYDEN CRYSTALS

<jats:title>Abstract</jats:title> <jats:p>1. Synthetic detergents of the anionic, cationic and nonionic types result in the rapid and constant formation of Charcot-Leyden crystals from eosinophils.</jats:p> <jats:p>2. Charcot-Leyden crystals have a negative crystalline birefringence and form penetration twins.</jats:p> <jats:p>3. The changes taking place in the eosinophil in the formation of Charcot-Leyden crystals under the influence of wetting agents, utilizing phase and polarizing microscopy, are described.</jats:p> <jats:p>4. In the formation of Charcot-Leyden crystals with wetting agents, the nucleus of the eosinophil lyses with no appreciable effect on the granules.</jats:p> <jats:p>5. In the formation of Charcot-Leyden crystals with a wetting agent, there is no change in the lipoid cortex of the eosinophil as demonstrated by staining with sudan black B.</jats:p> <jats:p>6. Charcot-Leyden crystals undergo changes on standing that affect their solubilities.</jats:p> <jats:p>7. The staining reactions and solubilities of Charcot-Leyden crystals are described.</jats:p> <jats:p>8. Oxyhemoglobin crystals constantly form from red cells on exposure to Aerosol MA; on two occasions, tyrosine crystals formed from the blood of a patient with chronic myelogenous leukemia.</jats:p> <jats:p>9. Evidence is offered that Charcot-Leyden crystals are crystalline proteins derived only from the nucleus of the eosinophil.</jats:p>