title: IL-9 enhances the growth of human mast cell progenitors under stimulation with stem cell factor.
abstract: We examined the effects of IL-9 on human mast cell development from CD34(+) cord blood (CB) and peripheral blood cells in serum-deprived cultures. IL-9 apparently enhanced cell production under stimulation with stem cell factor (SCF) from CD34(+) CB cells. A great majority of the cultured cells grown with SCF + IL-9 became positive for tryptase at 4 wk. In methylcellulose cultures of CD34(+) CB cells, IL-9 increased both the number and size of mast cell colonies grown with SCF. Furthermore, SCF + IL-9 caused an exclusive expansion of mast cell colony-forming cells in a 2-wk liquid culture of CD34(+) CB cells, at a level markedly greater than for SCF alone. Clonal cell cultures and RT-PCR analysis showed that the targets of SCF + IL-9 were the CD34(+)CD38(+) CB cells rather than the CD34(+)CD38(-) CB cells. IL-9 neither augmented the SCF-dependent generation of progeny nor supported the survival of 6-wk-cultured mast cells. Moreover, there was no difference in the appearance of tryptase(+) cells and histamine content in the cultured cells between SCF and SCF + IL-9. The addition of IL-9 increased numbers of mast cell colonies grown with SCF from CD34(+) peripheral blood cells in children with or without asthma. It is of interest that mast cell progenitors of asthmatic patients responded to SCF + IL-9 to a greater extent than those of normal controls. Taken together, IL-9 appears to act as a potent enhancer for the SCF-dependent growth of mast cell progenitors in humans, particularly asthmatic patients.
authors.affiliation: Department of Pediatrics, School of Medicine, Graduate School of Medicine, Shinshu University, Matsumoto, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Matsuzawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sakashita
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Kinoshita
authors.forename: Susumu
authors.initials: S
authors.lastname: Ito
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yamashita
authors.forename: Kenichi
authors.initials: K
authors.lastname: Koike
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology / Q000502:physiology*; D000293:Adolescent; D018952:Antigens, CD34 / Q000096:biosynthesis / Q000097:blood; D001249:Asthma / Q000276:immunology / Q000473:pathology; D002452:Cell Count; D002454:Cell Differentiation / Q000276:immunology; D002455:Cell Division / Q000276:immunology; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D002999:Clone Cells; D003114:Colony-Forming Units Assay; D016895:Culture Media, Serum-Free; D004338:Drug Combinations; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology; D016906:Interleukin-9 / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D008297:Male; D008407:Mast Cells / Q000166:cytology* / Q000276:immunology*; D019089:Stem Cell Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology*; D013926:Thrombopoietin / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D018952:Antigens, CD34; D016895:Culture Media, Serum-Free; D004338:Drug Combinations; D016906:Interleukin-9; D019089:Stem Cell Factor; D015847:Interleukin-4; D013926:Thrombopoietin