Quantitative Measurement of the Erythrocytic and Granulocytic Cells of the Marrow and Blood1

In the preceding article, a method for measur- ing total marrow cellularity was described (1).The purpose of this report is to relate numerically (a) the erythroid marrow to the circulating red cell mass, and (b) the granulocytic marrow to the circulating granulocytic leukocytes.Results in three animal species and in man are reported, and are compared with data obtained by other methods. MATERIALS AND METHODSStudies were performed on Sprague-Dawley rats weighing between 200 to 300 Gm., New Zealand white rabbits weighing 2 to 33/ Kg., and 2 to 3 Kg.male Rhesus monkeys.All animals were given approximately 15 mg.per Kg. of iron as iron dextran2 at least two weeks before the study to insure adequate iron stores.Only those animals with hemoglobin levels above 13 Gm.were used.Reticulocyte counts in rabbits were required to be below 4 per cent and those of monkeys and rats below 3 per cent before the animals were considered suitable for study.Clinical studies were performed on male patients with controlled tuberculosis who were being subjected to thoracotomy.Prior to operation, these patients had normal leukocyte counts and were afebrile, but plasma iron values were usually subnormal.On the morning of operation their red counts were above 4.5 X 106; their reticulocyte counts were less than 2 per cent.They had not been transfused during the previous six months. I. Erythrocytic seriesA. Studies of the circulating erythrocytes.A red count was performed by enumerating a minimum of 1,000 cells from two or more pipettes in two counting cham- bers.Reticulocyte counts were performed on dried