Production of interleukin 1beta by human hematopoietic progenitor cells.
The production of interleukin 1beta (IL-1beta) by human hematopoietic stem/progenitor cells was studied to explore the concept that these cells are not merely responders to stimuli from their microenvironment, but can themselves produce a powerful biomodulator. Cells with a CD34+ CD45RA(lo) CD71(lo) phenotype were purified from human umbilical cord blood and cultured one per well in serum-free medium with a mixture of cytokines. Cells that had divided over 2-5 d to form doublets were identified and the daughter cells were studied individually. 91% (460/506) of daughter cells had clonogenic potential. Analysis of these individual daughter cells by reverse transcription-polymerase chain reaction showed that 29% of them (14/48) were positive for IL-1beta mRNA. One of the cells that was strongly positive for IL-1beta mRNA had a sibling that generated 366,000 cells of multiple lineages after 14 d. IL-1beta converting enzyme mRNA, which is necessary to produce IL-1beta, was also detected by reverse transcription-polymerase chain reaction at the single-cell level. Moreover, enzyme immunoassay for mature secreted IL-1beta in culture supernatants demonstrated the production of IL-1beta protein by these cells. This was confirmed by fluorescent immunostaining of the cells for human IL-1beta which showed a significant portion of positive cells. Taken together, the results demonstrate the capacity of early hematopoietic cells to synthesize IL-1beta. The capacity of human hematopoietic stem/progenitor cells to produce IL-1beta may be involved in regulation of their proliferation and differentiation under certain circumstances and dysregulation of this process may be modified in leukemogenesis.
Watari
K
K
The Biomedical Research Centre, University of British Columbia, Vancouver, Canada.
Mayani
H
H
Lee
F
F
Dragowska
W
W
Lansdorp
P M
PM
Schrader
J W
JW
D000199:Actins / Q000235:genetics; D015703:Antigens, CD / Q000378:metabolism; D018952:Antigens, CD34 / Q000235:genetics / Q000378:metabolism; D000944:Antigens, Differentiation, B-Lymphocyte / Q000378:metabolism; D001483:Base Sequence; D020170:Caspase 1; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000235:genetics; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011990:Receptors, Transferrin
D000199:Actins; D015703:Antigens, CD; D018952:Antigens, CD34; D000944:Antigens, Differentiation, B-Lymphocyte; C068126:CD71 antigen; D017931:DNA Primers; D007375:Interleukin-1; D012333:RNA, Messenger; D011990:Receptors, Transferrin; D017493:Leukocyte Common Antigens; D003546:Cysteine Endopeptidases; D020170:Caspase 1