Figure 2.

Cell-mediated immunity. (A) No differences were observed after vaccination measured by the ³H-thymidine assay for cell proliferation. (B) An increase in the percentage of CD45RA⁺ cells was observed 1 month after vaccination in the CD8⁺ and CD4⁺ cell lineages stimulated with influenza antigen. (C) An increase in the mean frequency of CD4⁻/CD8⁻/CD27⁺ cells (probable precursors of the lymphoid lineage) was observed with influenza antigen stimulation, prior to and following vaccination. The figure shows flow cytometry plots for one representative patient.