With an improved method of tissue culture of peripheral leucocytes of our own design, the authors carried out systematic observations on the peripheral leucocyte culture from the normal, various kinds of leukemias, leukemoid reactions, and hypoplastic anemia. As for the culture method we have devised a method of silicon oil coating on the blood containers, a method which will least affect the cell function as compared with the conventional culture method. As the results we have found that the tissue growth in the case of peripheral leucocyte culture of normal persons ceases after six-hour culture and also we have recognized a peculiar finding, a growth like a corona-shape, in which an empty space appears in the inner part of growth area along with the lapse of time. In every
leukemic case, without presenting growth area like a corona, the cell density is high and the outer zone of growth area becomes sharply demarcated as in the case with bone-marrow culture and also the growth continues even after 12 hours. At this instance we have noticed many mitoses of immature cells. Moreover, the maturation of immature cells has been observed and it has also been possible to distinguish to what type these immature cells belonged. In the leukemoid reaction no growth pattern Characteristic to the leukemia can be recognized, and at a glance it can easily be differentiated from the leukemia. In the case of hypoplastic anemia although the growth area is like that of the normal presenting a corona-like shape, the cell density is lower and the function of leucccytes is lesser than the normal. From these results we believe that the peripheral leucocyte culture is clinically useful.</p
