Table 2.
Comparison of antibody responses in plasma from patients with uncomplicated or severe malaria
| Parameter | Value for the indicated group (mean [±SD]) |
P valuee | |
|---|---|---|---|
| Uncomplicated malaria (n = 39) | Severe malaria (n = 46) | ||
| Age (mo.) | 14.8 (±9.0) | 12.8 (±7.9) | 0.26 |
| IgG ELISA (OD405 value)a | |||
| AMA1-D10 | 0.69 (±0.28) | 0.46 (±0.22) | 0.0002 |
| MSP2-FC27 | 0.90 (±0.30) | 0.67 (±0.25) | 0.0005 |
| EBA181 | 0.13 (±0.18) | 0.06 (±0.35) | 0.005 |
| MSP2-3D7 | 0.8 (±0.32) | 0.67 (±0.21) | 0.03 |
| EBA175 | 0.1 (±0.14) | 0.07 (±0.08) | 0.6 |
| EBA140 | 0.06 (±0.09) | 0.06 (±0.05) | 0.2 |
| MSP1 | 0.26 (±0.36) | 0.28 (±0.27) | 0.3 |
| Rh2 | 0.18 (±0.24) | 0.18 (±0.23) | 1.0 |
| Rh4 | 0.03 (±0.05) | 0.05 (±0.05) | 0.06 |
| IgM ELISA (OD405 value)a | |||
| MSP2-FC27 | 0.22 (±0.14) | 0.19 (±0.09) | 0.4 |
| MSP2-3D7 | 0.21 (±0.12) | 0.19 (±0.12) | 0.09 |
| NH4SCN ELISA (affinity index)a | |||
| MSP2-FC27 | 0.9 (±0.68) | 0.88 (±0.54) | 0.8 |
| MSP-3D7 | 0.98 (±0.7) | 0.61 (±0.26) | 0.09 |
| SPR (kd [s−1])b | |||
| AMA1 | 0.00018 (±0.00011) | 0.00026 (±0.00022) | 0.04 |
| MSP2-FC27 | 0.00072 (±0.00022) | 0.00076 (±0.00023) | 0.4 |
| MSP2-3D7 | 0.00046 (±0.00022) | 0.00052 (±0.00023) | 0.3 |
| Invasion (%)c | |||
| UAS31 | 57.9 (±24.0) | 70.0 (±23.0) | 0.006 |
| UAM37 | 72.0 (±32.0) | 72.0 (±29) | 0.7 |
| Initial clinical parasitemia (%)d | 2.5 (±1.4) | 6.9 (±7.3) | 0.0003 |
a
Total IgM/IgG levels to different recombinant antigens were estimated using ELISAs, and an extended analysis of MSP2 antigens was performed for estimation of affinity using NH4SCN ELISAs.
b
kd (s−1) values were measured by SPR.
c
Invasion was determined for two clinical isolates.
d
Initial clinical parasitemia in the patients was determined by counting Giemsa slides.
e
Differences between means were determined by a Mann-Whitney t test. Significant P values are in boldface.