Abstract
Normal human neutrophil leukocytes are suggested as references for a microspectrophotometrically quantitated PAS reaction in biological material. Analysis of variance of values for the total extinction at 546 mµ in PAS-stained, single, normal neutrophils proved these cells to be suitable references. Methanol-fixed, smeared neutrophils could be stored for several months without changing their amount of PAS reactive material. A person with a mean for the amount of PAS reactive material in neutrophils that lay close to the average in a normal material of 20 persons was chosen as the original reference subject. New reference series of neutrophils were related to the original one, thus obtaining a continuous reference system. The results are based upon microspectrophotometric measurements of about 3500 individual neutrophils.