Naive human CD4+ T cells are a major source of lymphotoxin alpha.
It is generally accepted that immunologically naive T cells display a very restricted cytokine production profile consisting mainly of IL-2, which is used as an autocrine growth factor. Here we report that activated naive CD4+ T cells, of neonatal or adult origin, express very high levels of soluble lymphotoxin (LT) alpha (LTalpha3), as determined by ELISA, RNase protection assay, and intracytoplasmic staining. Besides LTalpha3 and IL-2, these cells also produce high levels of TNF-alpha together with significant amounts of IFN-gamma and IL-13. Naive cells also express LTbeta mRNA and the membrane form of LTalpha (LTalphabeta). On average, naive CD4+ T cells secrete four times more LTalpha3 than Th1-like cells, twice more than naive CD8+ T cells, and ten times more than B cells. Thus, naive T cells express a large spectrum of cytokines, mainly of the Th1 type, and the very high levels of LTalpha3/TNF-alpha that they release may play an hitherto unsuspected role in the early stage of T cell-dependent immune responses.
Ohshima
Y
Y
Centre Hospitalie Université de Montreal Research Centre, University of Montreal, Quebec, Canada.
Yang
L P
LP
Avice
M N
MN
Kurimoto
M
M
Nakajima
T
T
Sergerie
M
M
Demeure
C E
CE
Sarfati
M
M
Delespesse
G
G
D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D006801:Humans; D007231:Infant, Newborn; D007371:Interferon-gamma / Q000378:metabolism; D018793:Interleukin-13 / Q000378:metabolism; D007399:Interphase / Q000276:immunology; D008233:Lymphotoxin-alpha / Q000096:biosynthesis / Q000378:metabolism*; D012995:Solubility; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D018793:Interleukin-13; D008233:Lymphotoxin-alpha; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma