Table 1. Antibody responses to Plasmodium falciparum antigens.
| Antigen | Antibody Prevalencea, % (95% CI) | Antibody Level, AUb, Geometric Mean, (Range) | Fold increase between Day 0 and 14 Levels | ||
| Day 0 | Day 14 | Day 0 | Day 14 | (95% CI) | |
| CSP | 37.8 (30.3–46.0) | 39.0 (30.4–48.3) | 10.4 (1.2–3485.9) | 10.0 (1.2–2901.8) | 1.0 (0.9–1.2), p = 0.5 |
| LSA | 87.4 (81.8–91.4) | 93.1 (87.4–96.4) | 6.4 (0.06–10000.0) | 10.5 (0.06–4265.9) | 1.6 (1.3–2.1), p≤0.001 |
| AMA-1 | 62.6 (53.5–70.9) | 73.6 (64.8–80.8) | 1.9 (0.05–2360.4) | 3.3 (0.05–1899.3) | 1.5 (1.0–2.1), p = 0.03 |
| MSP-1 | 94.8 (90.6–97.1) | 99.5 (96.2–99.9) | 6.3 (0.02–3597.0) | 17.0 (0.06–1154.8) | 2.6 (1.9–3.6), p≤0.001 |
| MSP-2 | 86.5 (79.6–91.3) | 96.8 (93.1–98.5) | 2.0 (0.01–589.6) | 6.5 (0.01–1072.3) | 3.1 (2.3–4.2), p≤0.001 |
| MSP-3 | 15.2 (10.4–21.6) | 34.6 (26.9–43.3) | 3.3 (0.8–1323.5) | 7.0 (0.8–1051.3) | 2.2 (1.7–2.8), p≤0.001 |
| GLURP-R0 | 25.5 (19.3–33.0) | 31.1 (23.2–40.3) | 3.5 (0.6–208.6) | 4.1 (0.6–126.3) | 1.2 (1.0–1.5), p = 0.03 |
| GLURP-R2 | 40.4 (32.5–48.9) | 52.8 (43.4–62.0) | 7.1 (0.6–2216.3) | 10.0 (0.6–843.5) | 1.4 (1.1–1.8), p = 0.01 |
a
Positive cutoff = mean of 20 P. falciparum unexposed controls +3 standard deviations.
b
AU = arbitrary units, where an AU of 100 is equivalent to the antibody level of pooled serum from 50 African adults.
Note: Generalized estimating equations (GEE) were used to estimate antibody prevalence, geometric mean antibody level, and fold change.
Circumsporozoite protein (CSP); liver stage-antigen (LSA); apical membrane antigen 1 (AMA-1); merozoite surface protein 1, 2, or 3 (MSP-1, MSP-2, MSP-3); amino- or carboxy-terminal region of glutamine rich protein (GLURP-R0, GLURP-R2).