Analysis of type 2 immunity in vivo with a bicistronic IL-4 reporter.
Effector T cells mediate adaptive immunity and immunopathology, but methods for tracking such cells in vivo are limited. We engineered knockin mice expressing IL-4 linked via a viral IRES element with enhanced green fluorescent protein (EGFP). Reporter T cells primed under Th2 conditions showed sensitive and faithful EGFP expression and maintained endogenous IL-4. After Nippostrongylus infection, reporter expression demonstrated the evolution of type 2 immunity from tissue lymphocytes and thence to lymph node CD4(+) T cells, which subsequently migrated into tissue. The appearance of EGFP(+) CD4(+) T cells in tissue, but not in lymph nodes, was Stat6-dependent. Transferred EGFP(+) CD4(+) T cells from infected animals conferred protection against Nippostrongylus to immunodeficient mice. These mice will provide a valuable reagent for assessing immunity in vivo.
Mohrs
M
M
Howard Hughes Medical Institute, Departments of Medicine and Microbiology/Immunology, University of California, San Francisco 94143, USA.
Shinkai
K
K
Mohrs
K
K
Locksley
R M
RM
D000818:Animals; D017930:Genes, Reporter / Q000235:genetics*; D007109:Immunity; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008817:Mice, Mutant Strains; D009559:Nippostrongylus / Q000276:immunology*; D017206:Strongylida Infections / Q000276:immunology*
D015847:Interleukin-4