Table 6.
Functional relationship between IL12B genotypes/haplotypes and IL-12p40 and IFN-γ.
| Uncomplicated Malaria | Severe Malaria | |||||||
|---|---|---|---|---|---|---|---|---|
|
IL12Bpro (rs17860508) |
1.1 | 1.2 | 2.2 | p | 1.1 | 1.2 | 2.2 | p |
| IL-12p40 (pg/mL), median (IQR) | 10.0 (10.0–10.0) | 75.4 (13.5–112.5) | 20.0 (10.0–69.3) | 0.002 | 37.6 (16.8–229.8) | 99.2 (27.1–135.0) | 95.1 (35.9–131.4) | 0.919 |
| sample size | 7 | 30 | 19 | 4 | 16 | 5 | ||
| IFN-γ (pg/mL), median (IQR) | 438.5a(227.7–585.2) | 338.5 (125.5–522.2) | 140.0 (43.0–314.0) | 0.004 | 550.5 (204.5–692.7) | 340.5 (164.7–629.7) | 242.0 (105.0–677.0) | 0.508 |
| sample size | 10 | 94 | 19 | 12 | 62 | 15 | ||
| IL12B 3’ UTR (rs3212227) | TT | TG | GG | TT | TG | GG | ||
| IL-12p40 (pg/mL), median (IQR) | 22.1 (10.0–87.8) | 41.1 (10.0–104.8) | 26.7 (10.0–108.3) | 0.622 | 95.1 (26.6–131.4) | 65.6 (21.0–143.5) | 76.7 (27.0–148.0) | 0.892 |
| sample size | 20 | 28 | 13 | 9 | 6 | 10 | ||
| IFN-γ (pg/mL), median (IQR) | 160.0 (88.0–413.0) | 329.0 (125.0–450.0) | 374.5 (230.5–593.0) | 0.083 | 382.5 (113.5–623.2) | 265.0 (170.5–633.0) | 432.5 (162.5–623.5) | 0.921 |
| sample size | 23 | 55 | 26 | 16 | 29 | 28 | ||
| Haplotypes | IL12Bpro-2/3’ UTR-T | IL12Bpro-2/3’ UTR-G | IL12Bpro-1/3’ UTR-T | IL12Bpro-1/3’ UTR-G | ||||
| 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | |
| IL-12p40 (pg/mL), median (IQR) | 32.2 (10.0–112.9) | 49.8 (10.2–103.5) | 38.1 (10.0–102.5) | 74.3 (15.6–118.6) | 39.9 (12.8–108.0) | 10.0 (10.0–92.4) | 27.1 (10.0–95.1) | 39.9 (11.8–116.9) |
| sample size | 27 | 54 | 62 | 19 | 70 | 11 | 33 | 48 |
| p-value | 0.596 | 0.354 | 0.263 | 0.219 | ||||
| IFN-γ (pg/mL), median (IQR) | 387.0 (164.0–597.0) | 267.5 (117.5–527.0) | 321.5 (128.0–542.0) | 338.0 (130.0–495.0) | 314.0 (125.0–517.0) | 406.5 (160.5–619.5) | 199.0 (108.5–537.5) | 343.5 (159.0–541.0) |
| sample size | 65 | 116 | 128 | 53 | 157 | 24 | 51 | 130 |
| p-value | 0.06 | 0.953 | 0.252 | 0.158 | ||||
Patients with P. falciparum infection were categorized according to severe malaria according to WHO criteria (WHO, 2000). Patients were categorized as hyperparasitaemia (≥250,000 parasites/µL) vs. non- hyperparasitaemia (<250,000 parasites/µL). IL-12p40 and IFN-γ were measured in those subjects with adequate volumes of available plasma samples. Across group comparisons were determined by Kruskal-Wallis test, while pairwise comparisons was by Mann-Whitney U test. Results are presented as median and interquatile range (IQR), with p≤0.05 considered statistically significant. For the haplotypic constructions, results are presented as those without (code=0) versus those with (code=1) the particular haplotypes.