Table III. Association between Abs and protection from symptomatic malaria.
| Ag | Region | Tertile | uHR (95% CI) | p Value | Adjusted HR (95% CI) | p Value |
|---|---|---|---|---|---|---|
| Surface proteins (GPI-anchored) | ||||||
| MSP1 | MSP1–19 | MvL | 0.53 (0.23–1.21) | 0.132 | 0.66 (0.28–1.54) | 0.334 |
| HvL | 0.42 (0.17–1.03) | 0.059 | 0.57 (0.22–1.44) | 0.235 | ||
| MSP1 | MSP1–42 | MvL | 0.39 (0.15–1.01) | 0.052 | 0.47 (0.18–1.21) | 0.116 |
| HvL | 0.59 (0.26–1.35) | 0.211 | 0.80 (0.34–1.85) | 0.596 | ||
| MSP2 | Full length | MvL | 0.69 (0.31–1.55) | 0.369 | 0.87 (0.38–2.01) | 0.747 |
| HvL | 0.42 (0.16–1.09) | 0.073 | 0.56 (0.21–1.49) | 0.246 | ||
| MSP4 | Full length | MvL | 0.29 (0.11–0.82) | 0.019 | 0.36 (0.13–1.01) | 0.053 |
| HvL | 0.68 (0.31–1.49) | 0.330 | 0.92 (0.40–2.08) | 0.833 | ||
| MSP10 | Full ectodomain | MvL | 0.26 (0.10–0.69) | 0.007 | 0.31 (0.11–0.83) | 0.020 |
| HvL | 0.38 (0.16–0.92) | 0.031 | 0.42 (0.17–1.02) | 0.055 | ||
| Pf12 | Full ectodomain | MvL | 0.53 (0.22–1.27) | 0.155 | 0.60 (0.25–1.44) | 0.251 |
| HvL | 0.58 (0.24–1.39) | 0.223 | 0.70 (0.29–1.68) | 0.422 | ||
| Pf38 | Full ectodomain | MvL | 0.34 (0.14–0.82) | 0.016 | 0.36 (0.15–0.88) | 0.024 |
| HvL | 0.31 (0.12–0.78) | 0.013 | 0.34 (0.13–0.87) | 0.024 | ||
| Surface proteins (not-GPI anchored) | ||||||
| MSP3 | Full ectodomain | MvL | 0.20 (0.07–0.59) | 0.004 | 0.26 (0.09–0.77) | 0.015 |
| HvL | 0.44 (0.19–1.01) | 0.052 | 0.58 (0.24–1.36) | 0.209 | ||
| MSP3 | Long synthetic peptide | MvL | 0.38 (0.16–0.90) | 0.028 | 0.44 (0.18–1.06) | 0.066 |
| HvL | 0.27 (0.10–0.72) | 0.009 | 0.36 (0.13–1.00) | 0.049 | ||
| MSP6 | Full ectodomain | MvL | 0.62 (0.28–1.36) | 0.230 | 0.75 (0.34–1.69) | 0.491 |
| HvL | 0.23 (0.08–0.70) | 0.009 | 0.32 (0.10–0.98) | 0.046 | ||
| MSP7 | Full ectodomain | MvL | 0.32 (0.12–0.88) | 0.027 | 0.39 (0.14–1.08) | 0.071 |
| HvL | 0.66 (0.30–1.46) | 0.304 | 0.82 (0.36–1.85) | 0.635 | ||
| MSRP1 | Full ectodomain | MvL | 0.19 (0.07–0.57) | 0.003 | 0.23 (0.08–0.69) | 0.009 |
| HvL | 0.35 (0.15–0.83) | 0.017 | 0.44 (0.18–1.06) | 0.066 | ||
| ABRA/MSP9 | Full ectodomain | MvL | 0.36 (0.15–0.86) | 0.022 | 0.41 (0.17–1.00) | 0.049 |
| HvL | 0.32 (0.13–0.81) | 0.016 | 0.42 (0.16–1.10) | 0.077 | ||
| H103MSP11 | Full ectodomain | MvL | 0.49 (0.21–1.14) | 0.098 | 0.55 (0.23–1.29) | 0.167 |
| HvL | 0.36 (0.14–0.92) | 0.032 | 0.46 (0.18–1.18) | 0.107 | ||
| GLURP | R2 peptide | MvL | 0.65 (0.28–1.51) | 0.320 | 0.81 (0.35–1.89) | 0.625 |
| HvL | 0.49 (0.20–1.22) | 0.127 | 0.65 (0.26–1.64) | 0.363 | ||
| SERA5 | Full ectodomain | MvL | 0.25 (0.10–0.63) | 0.003 | 0.31 (0.12–0.78) | 0.013 |
| HvL | 0.27 (0.11–0.68) | 0.006 | 0.33 (0.13–0.83) | 0.018 | ||
| Pf41 | Full ectodomain | MvL | 0.27 (0.11–0.69) | 0.006 | 0.31 (0.12–0.80) | 0.016 |
| HvL | 0.35 (0.14–0.83) | 0.018 | 0.39 (0.16–0.95) | 0.039 | ||
| MSPDBL1 | DBL domain | MvL | 0.67 (0.31–1.45) | 0.314 | 0.78 (0.36–1.7) | 0.532 |
| HvL | 0.18 (0.05–0.61) | 0.006 | 0.23 (0.07–0.80) | 0.021 | ||
| MSPDBL2 | Full ectodomain | MvL | 0.34 (0.13–0.86) | 0.023 | 0.41 (0.16–1.06) | 0.067 |
| HvL | 0.39 (0.16–0.94) | 0.036 | 0.55 (0.22–1.37) | 0.200 | ||
| Microneme proteins | ||||||
| AMA1 | Full ectodomain | MvL | 0.31 (0.12–0.77) | 0.012 | 0.40 (0.16–1.02) | 0.055 |
| HvL | 0.32 (0.13–0.80) | 0.015 | 0.36 (0.14–0.91) | 0.031 | ||
| EBA140 | Region II | MvL | 0.59 (0.27–1.31) | 0.196 | 0.61 (0.28–1.35) | 0.225 |
| HvL | 0.24 (0.08–0.71) | 0.010 | 0.28 (0.09–0.83) | 0.022 | ||
| EBA140 | Region III–V | MvL | 0.35 (0.15–0.83) | 0.017 | 0.40 (0.17–0.95) | 0.039 |
| HvL | 0.20 (0.07–0.58) | 0.003 | 0.25 (0.09–0.76) | 0.014 | ||
| EBA175 | Region F2 | MvL | 0.59 (0.26–1.29) | 0.182 | 0.64 (0.28–1.41) | 0.268 |
| HvL | 0.24 (0.08–0.73) | 0.011 | 0.51 (0.11–0.98) | 0.046 | ||
| EBA175 | Region II | MvL | 0.27 (0.10–0.72) | 0.009 | 0.30 (0.11–0.81) | 0.018 |
| HvL | 0.46 (0.20–1.06) | 0.069 | 0.61 (0.26–1.44) | 0.263 | ||
| EBA175 | Region III–V | MvL | 0.39 (0.17–0.90) | 0.028 | 0.50 (0.21–1.16) | 0.106 |
| HvL | 0.21 (0.07–0.61) | 0.004 | 0.27 (0.09–0.81) | 0.019 | ||
| EBA181 | Region III–V | MvL | 0.37 (0.15–0.88) | 0.025 | 0.42 (0.17–1.01) | 0.052 |
| HvL | 0.32 (0.13–0.82) | 0.017 | 0.40 (0.16–1.04) | 0.060 | ||
| GAMA | Full ectodomain | MvL | 0.23 (0.08–0.61) | 0.003 | 0.27 (0.10–0.73) | 0.010 |
| HvL | 0.28 (0.11–0.71) | 0.007 | 0.35 (0.14–0.89) | 0.027 | ||
| GAMA | N-terminal | MvL | 0.12 (0.03–0.39) | <0.001 | 0.13 (0.04–0.45) | 0.001 |
| HvL | 0.25 (0.10–0.63) | 0.003 | 0.31 (0.13–0.80) | 0.015 | ||
| GAMA | C-terminal | MvL | 0.60 (0.27–1.33) | 0.210 | 0.69 (0.31–1.53) | 0.360 |
| HvL | 0.25 (0.08–0.75) | 0.013 | 0.27 (0.09–0.82) | 0.021 | ||
| Ripr | EGF-like domain | MvL | 0.41 (0.18–0.94) | 0.035 | 0.51 (0.22–1.21) | 0.127 |
| HvL | 0.20 (0.07–0.60) | 0.004 | 0.24 (0.08–0.73) | 0.012 | ||
| SUB2 | N-terminal | MvL | 0.32 (0.13–0.76) | 0.010 | 0.41 (0.17–0.99) | 0.046 |
| HvL | 0.19 (0.07–0.57) | 0.003 | 0.27 (0.09–0.81) | 0.020 | ||
| Rhoptry proteins | ||||||
| RAMA | Full ectodomain | MvL | 0.33 (0.14–0.78) | 0.012 | 0.40 (0.17–0.98) | 0.044 |
| HvL | 0.18 (0.06–0.54) | 0.002 | 0.23 (0.08–0.70) | 0.010 | ||
| PfRh2 | PfRh2-297 | MvL | 0.46 (0.20–1.07) | 0.073 | 0.52 (0.22–1.23) | 0.136 |
| HvL | 0.37 (0.15–0.95) | 0.039 | 0.42 (0.16–1.08) | 0.070 | ||
| PfRh2 | PfRh2-2030 | MvL | 0.68 (0.32–1.47) | 0.327 | 0.68 (0.31–1.48) | 0.334 |
| HvL | 0.19 (0.05–0.64) | 0.008 | 0.20 (0.06–0.70) | 0.012 | ||
| PfRh2 | PfRh2a | MvL | 0.28 (0.11–0.70) | 0.006 | 0.30 (0.12–0.77) | 0.012 |
| HvL | 0.25 (0.09–0.68) | 0.006 | 0.27 (0.10–0.73) | 0.010 | ||
| PfRh2 | PfRh2b | MvL | 0.44 (0.2–0.98) | 0.045 | 0.49 (0.22–1.08) | 0.076 |
| HvL | 0.09 (0.02–0.40) | 0.001 | 0.12 (0.03–0.52) | 0.005 | ||
| PfRh4 | PfRh4.2 | MvL | 0.58 (0.27–1.24) | 0.162 | 0.71 (0.33–1.55) | 0.393 |
| HvL | 0.11 (0.02–0.46) | 0.003 | 0.13 (0.03–0.58) | 0.007 | ||
| PfRh4 | PfRh4.9 | MvL | 0.63 (0.26–1.52) | 0.303 | 0.74 (0.31–1.79) | 0.504 |
| HvL | 0.70 (0.30–1.63) | 0.402 | 0.75 (0.32–1.77) | 0.516 | ||
| PfRh5 | Full ectodomain | MvL | 0.46 (0.20–1.06) | 0.068 | 0.53 (0.23–1.25) | 0.150 |
| HvL | 0.27 (0.10–0.72) | 0.010 | 0.35 (0.12–0.96) | 0.042 | ||
| RALP-1 | Full ectodomain | MvL | 0.36 (0.16–0.82) | 0.014 | 0.41 (0.18–0.93) | 0.033 |
| HvL | 0.09 (0.02–0.36) | 0.001 | 0.11 (0.03–0.48) | 0.003 | ||
| RhopH1(3.1) | N-terminal | MvL | 0.40 (0.18–0.92) | 0.030 | 0.47 (0.20–1.08) | 0.075 |
| HvL | 0.14 (0.04–0.48) | 0.002 | 0.19 (0.05–0.66) | 0.009 | ||
| RhopH1(2) | N-terminal | MvL | 0.49 (0.22–1.08) | 0.078 | 0.57 (0.25–1.28) | 0.173 |
| HvL | 0.15 (0.04–0.49) | 0.002 | 0.18 (0.05–0.64) | 0.008 | ||
| RON2 | N-terminal | MvL | 0.57 (0.26–1.25) | 0.163 | 0.72 (0.32–1.59) | 0.415 |
| HvL | 0.17 (0.05–0.58) | 0.005 | 0.21 (0.06–0.72) | 0.013 | ||
| RON4 | N-terminal | MvL | 0.54 (0.25–1.18) | 0.124 | 0.64 (0.29–1.41) | 0.272 |
| HvL | 0.10 (0.02–0.43) | 0.002 | 0.13 (0.03-0.59) | 0.008 | ||
| RON6 | C-terminal | MvL | 0.57 (0.26–1.24) | 0.153 | 0.69 (0.31–1.53) | 0.363 |
| HvL | 0.16 (0.05–0.54) | 0.003 | 0.21 (0.06–0.73) | 0.014 | ||
| Miscellaneous Ags | ||||||
| Pf113 | C-terminal | MvL | 0.27 (0.11–0.68) | 0.006 | 0.33 (0.13–0.83) | 0.018 |
| HvL | 0.22 (0.08–0.59) | 0.003 | 0.30 (0.11–0.84) | 0.021 | ||
| CSP | NANP repeat | MvL | 1.28 (0.50–3.24) | 0.606 | 1.39 (0.55–3.55) | 0.486 |
| HvL | 1.58 (0.65–3.87) | 0.316 | 1.86 (0.75–4.57) | 0.178 |
IgG responses were stratified into three equal groups (tertiles, n = 69 for each group) to examine the dose-response effect of Ag-specific Ab responses on subsequent episodes of symptomatic P. falciparum malaria. HRs were calculated using the Cox proportional-hazards model comparing those with medium-versus-low (MvL) and high-versus-low (HvL) levels of Abs for the risk for symptomatic malaria over a 6-mo follow-up (first symptomatic episode only). Covariates included in the adjusted model include age and the location of residence.
The p values < 0.05 are in bold type.
CI, Confidence interval.