GRANULOCYTE-MACROPHAGE COLONIES IN CULTURES OF HUMAN-FETAL LIVER-CELLS - MORPHOLOGIC AND ULTRASTRUCTURAL ANALYSIS OF PROLIFERATION AND DIFFERENTIATION

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  • 1 January 1980
    • journal article
    • research article
    • Vol. 8  (7) , 837-844
Abstract
Fetal liver cells from 6-12 wk old human fetuses were cultured in soft agar to study growth patterns of the granulocyte-macrophage colony forming cells CUFc) and to characterize the cellular components of these colonies by morphologic, cytochemical and ultrastructural methods. Liver cell suspensions prepared from 31 fetuses obtained by vaginal interruptions of pregnancies, were seeded in soft agar over feeder layers of normal human leukocytes. At all gestational ages examined, agar colony numbers ranged from 44 .+-. 15 to 89 .+-. 44/2 .times. 105 cells seeded. Colony frequencies, size and gross morphology closely resembled those derived from adult human marrow. Morphologic, cytochemical and ultrastructural examinations showed that 92% of the colonies were granulocytic with incomplete maturation, as found in adult human marrow colonies. Density fractionation of the cells produced a low density cellular fraction which gave a 3- to 5-fold improved cloning efficiency. This study shows that human fetal livers of 6-12 wk gestional age contain CFUc comparable to that found in adult marrow in their frequency, size, density and dependence on colony stimulating factor and which differentiate mainly into mature or immature granulocytes. The lack of granulopoiesis in vivo in the early human fetal liver is probably not related to CFUc deficiency or defective differentiation. An alternative explanation involving impaired regulatory mechanism(s) should be sought.