The CCR3 receptor is involved in eosinophil differentiation and is up-regulated by Th2 cytokines in CD34+ progenitor cells.
The involvement of chemokines in eosinophil recruitment during inflammation and allergic reactions is well established. However, a functional role for chemokines in eosinophil differentiation has not been investigated. Using in situ RT-PCR, immunostaining, and flow cytometric analysis, we report that human CD34+ cord blood progenitor cells contain CCR3 mRNA and protein. Activation of CD34+ progenitor cells under conditions that promote Th2 type differentiation up-regulated surface expression of the CCR3. In contrast, activation with IL-12 and IFN-gamma resulted in a significant decrease in the expression of CCR3. Eotaxin induced Ca2+ mobilization in CD34+ progenitor cells, which could explain the in vitro and in vivo chemotactic responsiveness to eotaxin. We also found that eotaxin induced the differentiation of eosinophils from cord blood CD34+ progenitor cells. The largest number of mature eosinophils was found in cultures containing eotaxin and IL-5. The addition of neutralizing anti-IL-3, anti-IL-5, and anti-GM-CSF Abs to culture medium demonstrated that the differentiation of eosinophils in the presence of eotaxin was IL-3-, IL-5-, and GM-CSF-independent. These results could explain how CD34+ progenitor cells accumulate and persist in the airways and peripheral blood of patients with asthma and highlight an alternative mechanism by which blood and tissue eosinophilia might occur in the absence of IL-5.
Lamkhioued
Bouchaib
B
Centre Hospitalier de l'Universite de Montreal, Research Center, Notre Dame Hospital, University of Montreal, Montreal, Quebec, Canada. b.Lamkhioued@umontreal.ca
Abdelilah
Soussi Gounni
SG
Hamid
Qutayba
Q
Mansour
Nabil
N
Delespesse
Guy
G
Renzi
Paolo M
PM
D000818:Animals; D018952:Antigens, CD34 / Q000096:biosynthesis*; D020013:Calcium Signaling / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D054413:Chemokine CCL11; D019742:Chemokines, CC / Q000378:metabolism / Q000494:pharmacology; D002631:Chemotactic Factors, Eosinophil / Q000378:metabolism / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000276:immunology; D016207:Cytokines / Q000502:physiology*; D004306:Dose-Response Relationship, Immunologic; D004338:Drug Combinations; D004804:Eosinophils / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology; D005434:Flow Cytometry; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology; D006131:Growth Inhibitors / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007106:Immune Sera / Q000494:pharmacology; D007377:Interleukin-3 / Q000276:immunology; D015848:Interleukin-5 / Q000276:immunology; D007700:Kinetics; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000096:biosynthesis; D054397:Receptors, CCR3; D019707:Receptors, Chemokine / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D018418:Th2 Cells / Q000276:immunology* / Q000378:metabolism; D013997:Time Factors; D015854:Up-Regulation / Q000276:immunology*
D018952:Antigens, CD34; C515456:CCL11 protein, human; C515350:CCR3 protein, human; C515457:Ccl11 protein, mouse; C515351:Ccr3 protein, mouse; D054413:Chemokine CCL11; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil; D016207:Cytokines; D004338:Drug Combinations; D006131:Growth Inhibitors; D007106:Immune Sera; D007377:Interleukin-3; D015848:Interleukin-5; D012333:RNA, Messenger; D054397:Receptors, CCR3; D019707:Receptors, Chemokine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor