The loss of uPA or uPAR does not alter CII-specific B- and T-cell responses. (A-C) CII-specific antibody titers were analyzed in the plasma of untreated (no CII) DBA/1J mice and CIA-challenged uPA WT and Plau^−/− or uPAR WT and Plaur^−/− mice (n = 5 or more mice per genotype). (D-E) Proliferation of splenocytes harvested from CIA-challenged uPA WT, Plau^−/−, uPAR WT, and Plaur^−/− mice following stimulation with either (D) heat-inactivated CII (100 μg/mL) or (E) direct T-cell receptor stimulation using anti–CD3 antibody as evaluated by [³H] thymidine incorporation. Note that for all T-cell analyses, n = 4 mice per genotype. All data are presented as mean ± standard error of the mean. P values were determined by Student t test.