A role for IL-5 in the induction of cytotoxic T lymphocytes in vivo.
IL-5 is generally regarded as a Th2 cytokine involved in eosinophil maturation and function and in B cell growth and antibody production, but without any well-established effects on T cells. Early reports suggested that IL-5 could stimulate the production of cytotoxic T lymphocytes (CTL) in vitro, but no evidence has been obtained to date for such a role in studies with IL-5-deficient (IL-5-/-) mice. Here we demonstrate that when oxidized mannan MUC1 fusion protein (M-FP) is used as an antigen in mice, IL-5 is required for the optimal generation of the CTL response. IL-5 was as effective as IL-2 for the induction of CTL from spleen cells in vitro and both CD4+ and CD8+ T cells from M-FP-immunized animals could be shown to secrete IL-5 in culture. In IL-5-/- mice, CTLp frequency was greatly diminished resulting in the inability to reject MUC1- tumors. Clearly, IL-5 is produced by functional T cells, especially the Tc1 type, after M-FP immunization and is required for an optimal CTL response to this antigen.
Apostolopoulos
V
V
The Austin Research Institute, ARMC, Heidelberg, Victoria, Australia. vapos@scripps.edu
McKenzie
I F
IF
Lees
C
C
Matthaei
K I
KI
Young
I G
IG
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D006801:Humans; D015848:Interleukin-5 / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D009374:Neoplasms, Experimental / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*
D016207:Cytokines; D015848:Interleukin-5