Adrenomedullin is expressed in cord blood hematopoietic cells and stimulates their clonal growth.
Adrenomedullin (AM) is a hypotensive peptide, which originates from the proteolytic cleavage of pro(p)AM and acts via AM22-52-sensitive receptors. Reverse transcription polymerase chain reaction allowed the detection of the specific mRNAs of pAM in the mononuclear hematopoietic cells of the cord blood and immunocytochemistry demonstrated their abundant AM-immunoreactivity. AM (10(-8) M) markedly enhanced clonal growth of cord blood hematopoietic cells cultured on semisolid media added with stem cell-growth promoting cytokines, and this effect was abolished by AM22-52 (10(-6) M). Collectively, these findings indicate that AM is expressed in and stimulates the proliferation of cord blood hematopoietic stem cells. Cord blood has been proposed as a source of stem cells alternative to bone marrow for allogeneic transplantation, and our study suggests that AM may be used, in addition to the classic cytokines, to expand in vitro cord blood stem cells in advance of their clinical use.
Del Pup
Laura
L
Department of Pharmaceutical Sciences, Section of Anatomy, University of Padua, I-35121 Padua, Italy.
Belloni
Anna S
AS
Carraro
Gianni
G
De Angeli
Sergio
S
Parnigotto
Pier Paolo
PP
Nussdorfer
Gastone G
GG
D053607:Adrenomedullin; D002455:Cell Division / Q000502:physiology*; D005312:Fetal Blood / Q000378:metabolism*; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger; D020133:Reverse Transcriptase Polymerase Chain Reaction
D010455:Peptides; D012333:RNA, Messenger; D053607:Adrenomedullin