CII-specific T- and B-cell responses are similar in fXIIIA^+/+ and fXIIIA^−/− mice. Flow cytometry-based analyses of CD3⁺/CD19⁻ total T-cell and CD3⁻/CD19⁺ total B-cell (A) numbers and (B) percentages within the draining popliteal lymph nodes of fXIIIA^+/+ and fXIIIA^−/− mice 10 days after immunization with CII in the footpad. Representative scatter dot plots highlight both similar (C) percentages of CD4⁺ and CD8⁺ T cells, and (D) CD4⁺ T-cell activation based on surface expression of CD44 in PLN of CII-immunized mice of both genotypes. Proliferation of splenocytes harvested from CIA-challenged fXIIIA^+/+ and fXIIIA^−/− after stimulation with either (E) heat-inactivated CII or (F) direct T-cell receptor stimulation using anti-CD3 antibody as evaluated by [³H] thymidine incorporation. Measurement of (G) IFN-γ and (H) IL-17A secretion by popliteal lymph node cells harvested from CII-immunized fXIIIA^+/+ and fXIIIA^−/− mice after ex vivo re-stimulation with CII (left panel) or anti-CD3 (right panel) antibody. Note that for all T-cell analyses (n = 4 mice per genotype). (I) CII-specific antibody titers in the plasma of CIA-challenged fXIIIA^+/+ and fXIIIA^−/− mice (n = 9 mice per genotype). All data are presented as mean ± standard error of the mean. CPM, counts per minute.