Table 2

Demographic characteristics of the study cohort and assays performed

Demographic or assay parameterDemographic or assay result by ageP value
20–30 yr old (young)65–85 yr old (elderly)
Demographics
    Age (yr; median ± SD)26 ± 374 ± 6<0.0001
    Age (yr; range)20–3065–85
Gender (no. [%])
    Male14 (46.7)12 (40)0.6021
    Female16 (53.3)18 (60)0.6020
Race (no. [%])
    Caucasian8 (26.7)7 (23.3)0.3903
    Hispanic11 (36.7)7 (23.3)0.4196
    African-American11 (36.7)16 (53.3)0.2776
Assay parameters [mean ± SD (no. of samples/assay)]
    Sample
        Plasma
            RSV neutralization (log2 titer)10.5 ± 2.2 (30)10.5 ± 2.1 (30)0.7758
            RSV F IgG ELISA (×103 titer)0.90 ± 0.31 (20)0.93 ± 0.36 (20)0.8821
        Nasal wash
            RSV F IgA ELISA (RLU)1.4 × 104 ± 1.2 × 104 (10)1.0 × 104 ± 1.1 × 104 (20)0.7694
        PBMC
            Memory B cell ELISPOT (% F-specific ASC/total IgG ASC)0.22 ± 0.25 (10)0.18 ± 0.5 (20)0.2413
            Memory T cell ELISPOT (SFC/106 PBMC)
                RSV A2 virus360 ± 130 (12)93 ± 41 (20)0.0262
                RSV F protein1,250 ± 420 (20)180 ± 80 (20)<0.0001
                CD4+ T cell peptides450 ± 180 (12)100 ± 60 (12)<0.0001
                CD8+ T cell peptides400 ± 210 (12)90 ± 55 (12)<0.0001
    CD107a flow cytometry (% CD107a+ CD8+ T cells)
        RSV F protein5.0 ± 1.6 (14)3.0 ± 1.7 (14)0.0173
        CD8+ T cell peptides4.7 ± 1.9 (14)2.3 ± 1.8 (14)0.0045
    Th1-Th2 cytokines (pg/ml)7,500 ± 3,100 (10)3,000 ± 800 (10)0.0004
        RSV F IFN-γ475 ± 450 (10)5,000 ± 4,000 (10)0.0017
        RSV F IL-131,000 ± 560 (10)3,000 ± 1,000 (10)0.0033