Leukokinetic Studies V. Uptake of Tritiated Diisopropylfluorophosphate by Leukocytes. ∗

Conclusions

Uptake of tritiated diisopropylfluorophosphate (H³-DFP) by various morphologic types of leukocytes after labeling in vitro and in vivo has been studied. When leukocytes from normal subjects and patients with leukemia were labeled in vitro, myelocytes labeled most intensely. Metamyelocytes and polymorphonuclear (PMN) neutrophils contained about half as many grains/cell as the myelocytes. Lymphocytes, eosinophils, and basophils did not bind significant amounts of DFP under the conditions of this study while a few monocytes were lightly labeled. Granulocytes in both blood and bone marrow were labeled after intravenous injection of H³-DFP. Relative degree of labeling was as follows: blood PMN neutrophils, 1.0; marrow PMN neutrophils, 0.3; marrow metamyelocytes. 0.2: and marrow myelocytes, 0.6. None of the other formed elements in either blood or bone marrow contained significant amounts of the label.