Competition does not affect antigen binding and presentation by low-affinity B cells. (A) Diagrammatic representation of the experimental protocol. (B, left) Flow cytometric analysis of antigen binding by B1-8^hi and B1-8^lo cells under different transfer conditions. Gated as CD19⁺Igλ⁺CD45.1⁺ (B1-8^hi) or CD19⁺Igλ⁺CFP⁺ (B1-8^lo). (right) Quantification of flow cytometry data. (C, left) Flow cytometric analysis of antigen presentation by B1-8^hi and B1-8^lo cells under different transfer conditions. Cell types are gated as in B; only Alexa Fluor 647⁺ cells are plotted. The Y-Ae antibody binds to the I-Eα_52–68 peptide in the context of I-A^b. (right) Quantification of flow cytometry data. Each symbol represents one mouse. Data are from two independent experiments with two mice per condition per experiment.