The CD7- T cell subset represents the majority of IL-5-secreting cells within CD4+CD45RA- T cells.
Absence of CD7 is a stable phenotype in a subset of normal human T cells. Most circulating CD7- T cells express the CD4CD45RO+CD45RA- memory phenotype. We analysed CD4+CD45RA- peripheral blood lymphocytes that were separated into CD7+ and CD7- for their in vitro cytokine secretion in response to different stimuli. The CD4+CD7- subpopulation was found to secrete significantly higher levels of IL-5 compared with the CD4+CD7- subset upon stimulation with ionomycin/phorbol myristate acetate (PMA) plus anti-CD28 MoAbs. In contrast to IL-5 secretion, IL-4 and interferon-gamma (IFN-gamma) secretion was not significantly different in CD7+ and CD7- T cells upon stimulation in vitro. The data indicate that the CD4+CD7- T cell represents the majority of IL-5-secreting cells within the population of CD4+CD45RA- memory T cells. Since CD4+CD7- T cells were found to be enriched in various skin lesions associated with eosinophilic infiltration, the results of our study support the hypothesis that skin-infiltrating CD7- T cells are one of the major sources of IL-5 responsible for the development of eosinophilic inflammation in certain skin diseases.
Reinhold
U
U
Department of Dermatology, University of Bonn, Germany.
Liu
L
L
Sesterhenn
J
J
Schnautz
S
S
Abken
H
H
D019011:Antigens, CD7 / Q000032:analysis*; D015704:CD4 Antigens / Q000032:analysis*; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D002478:Cells, Cultured; D002999:Clone Cells; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D015848:Interleukin-5 / Q000096:biosynthesis* / Q000378:metabolism*; D017493:Leukocyte Common Antigens / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000378:metabolism*
D019011:Antigens, CD7; D015704:CD4 Antigens; D015848:Interleukin-5; D015847:Interleukin-4; D007371:Interferon-gamma; D017493:Leukocyte Common Antigens