Human thymocytes express CCR-3 and are activated by eotaxin.
Eotaxin has been characterized as a chemokine involved in eosinophil activation; however, mRNA for this C-C chemokine has been shown to be constitutively expressed in thymus. Immunohistochemical analysis showed a punctate distribution pattern, with eotaxin expression localized mainly in the medulla and in Hassle's corpuscles. Moreover, the receptor for eotaxin, CCR-3, was detected on thymocytes, with the highest level of expression being on the CD8 single-positive population. Equilibrium binding analyses on unfractionated thymocytes demonstrated specific 125I-eotaxin binding profiles comparable with CCR-3 transfectants. Eotaxin induced cell migration and mobilization of intracellular calcium in all thymocytes except the immature CD4(-)/CD8(-) population. Eotaxin also induced the secretion of the chemokines interleukin-8, RANTES, and macrophage inflammatory protein-1beta from thymocyte cultures in vitro. These results suggest that eotaxin-induced thymocyte activation may have important physiological implications for lymphocyte mobilization within and from this lymphoid organ.
Franz-Bacon
K
K
Departments of Immunology and Molecular Biology, DNAX Research Institute, Palo Alto, CA, USA.
Dairaghi
D J
DJ
Boehme
S A
SA
Sullivan
S K
SK
Schall
T J
TJ
Conlon
P J
PJ
Taylor
N
N
Bacon
K B
KB
D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D054413:Chemokine CCL11; D054407:Chemokine CCL4; D018946:Chemokine CCL5 / Q000096:biosynthesis / Q000235:genetics; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil / Q000276:immunology / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte; D016207:Cytokines / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016209:Interleukin-8 / Q000096:biosynthesis / Q000235:genetics; D019402:Macrophage Inflammatory Proteins / Q000096:biosynthesis / Q000235:genetics; D054397:Receptors, CCR3; D019707:Receptors, Chemokine / Q000096:biosynthesis / Q000235:genetics*; D015728:Receptors, HIV / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
C515456:CCL11 protein, human; C515350:CCR3 protein, human; D054413:Chemokine CCL11; D054407:Chemokine CCL4; D018946:Chemokine CCL5; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil; D016207:Cytokines; D016209:Interleukin-8; D019402:Macrophage Inflammatory Proteins; D054397:Receptors, CCR3; D019707:Receptors, Chemokine; D015728:Receptors, HIV; D002118:Calcium