Figure 6.

CD4 T-helper cell function is not impaired in A1^−/− mice immunised with NP-KLH/Alum. (a) The numbers of total spleen cells of wild-type and A1^−/− mice that had been immunised i.p. with 100 μg/20 g body weight NP-KLH/Alum 14 days earlier were determined. (b) The frequencies and total numbers of CD4⁺CXCR5⁺PD-1⁺ Tfh cells in immunised wild-type and A1^−/− mice were analysed by flow cytometry. (c) The numbers of IgG1⁺NP⁺B220⁺ class-switched antigen-specific B cells and (d) Syndecan1⁺ plasma cells in the spleen were determined by flow cytometry. (e) Overall, 1 × 10⁶ spleen cells or bone-marrow cells were cultured overnight on NP16- or NP2-coated ELISA plates and ELISpot assays were performed. Antigen-specific plasma cells producing low (NP16) or high-affinity (NP2) antibodies against NP per 10⁶ cells were quantified. Pictures show representative ELISpots from wild-type or A1^−/− bone-marrow cells cultured overnight on NP2-coated ELISA plates. Bars represent means±S.E.M. (n=5)