Figure 4.

Numbers of tetramer⁺ T cells in relation to infection status and viral shedding after challenge with rhinovirus (RV)-A39. (A) Diagram of infection outcomes in 16 HLA-DR4⁺ subjects. Colored boxes denote heterogeneous infection profiles based on rise in serum neutralizing antibody titers ([NAT] day 21 versus day 0) and viral polymerase chain reaction (PCR) test (day 0). (B) Change in frequencies of tetramer⁺ T cells during the 7-week study period in infected and uninfected subjects, color coded according to the flow chart in A. Open symbols with dashed lines denote subjects who received placebo. Bars denote geometric means. *, P < .05. (C) Representative data showing RV-A39 tetramer staining at each time point in an infected subject. A tetramer displaying an irrelevant peptide (GAD555-567) was used as a control. (D) Time to viral shedding in subjects inoculated with RV-A39 classified as “high frequency” (≥10 tetramer⁺ cells per 10⁶ CD4⁺ T cells) and “low frequency” (<10 tetramer⁺ cells per 10⁶ CD4⁺ T cells) based on T-cell numbers on day 0. Abbreviations: ns, not significant; PL, placebo; PRO, probiotic.