Megakaryocyte potentiating activity of IL-1, IL-6 and GM-CSF as evaluated by their action on in vitro human megakaryocytic colonies.
We examined whether recombinant cytokines enhance the in vitro platelet production of interleukin-3 (IL-3)-induced human megakaryocytic colonies (Meg-colony). We classified Meg-colonies into four categories based on platelet production during in situ observation on day 14: type 0, absence of cytoplasmic processes in a colony; type 1, one to three processes in at least one megakaryocyte in a colony; type 2, four to eight processes; type 3, more than nine processes or division of cytoplasm. Type 3 colonies were considered to be platelet-producing. In control cultures, type 1 Meg-colonies were dominant, followed by type 2, type 3 and type 0. Of the cytokines added at the initiation of culture, interleukin-1 alpha (IL-1 alpha), interleukin-6 (IL-6), and granulocyte/macrophage colony stimulating factor (GM-CSF) significantly increased the number of colonies. Furthermore, these three cytokines significantly elevated the proportion of type 3 colonies. Interleukin-4 (IL-4), granulocyte-CSF, macrophage-CSF and erythropoietin did not affect the colony count or distribution of colony type. IL-1 alpha, IL-6 and GM-CSF also significantly elevated the proportion of type 3 colonies, even when added to the culture on days 8 or 11. These results indicate that IL-1 alpha, IL-6 and GM-CSF promote platelet production of in vitro Meg-colonies.
Takahashi
T
T
Second Department of Internal Medicine, Kyoto University School of Medicine, Japan.
Tsuyuoka
R
R
Ueda
Y
Y
Suzuki
A
A
Ichiba
S
S
Okuno
Y
Y
Nakamura
K
K
Imura
H
H
D001792:Blood Platelets / Q000166:cytology*; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D003593:Cytoplasm / Q000648:ultrastructure; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000502:physiology*; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D007375:Interleukin-1 / Q000502:physiology*; D015850:Interleukin-6 / Q000502:physiology*; D008533:Megakaryocytes / Q000166:cytology* / Q000648:ultrastructure; D011994:Recombinant Proteins / Q000502:physiology; D013997:Time Factors
D007375:Interleukin-1; D015850:Interleukin-6; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor