TABLE 2.
Invasion profilea | Isolateb | Symptoms of clinical severityc | % Inhibition byd:
|
PMRe | SIe | ABO blood group typef | ||
---|---|---|---|---|---|---|---|---|
Neuraminidase (50 mU/ml) | Trypsin (1 mg/ml) | Chymotrypsin (1 mg/ml) | ||||||
NmRTSCTS | 7G8 | 33.3 (19.2) | 80.7 (5.5) | 58.2 (7.5) | ||||
6 U | NA | 9.3 | 86.1 | 62.8 | 2.91 | 2.35 | O | |
7 U | NA | 12.8 | 83.0 | 76.6 | 4.70 | 1.28 | A | |
8 S | Pr, RD, An | 7.1 | 78.6 | 78.6 | 1.75 | 2.54 | A | |
9 S | C | −32.4 | 97.2 | 90.1 | 2.73 | 1.85 | O | |
10 S | Pr, RD | 0 | 87.8 | 73.2 | 2.05 | 2.06 | A | |
11 U | NA | 49.1 | 75.4 | 59.7 | 2.64 | 1.55 | O | |
12 S | Pr, RD | −22.8 | 85.7 | 62.9 | 2.50 | 1.96 | O | |
13 U | NA | 8.5 | 95.8 | 56.3 | 5.92 | 0.37 | O | |
14 U | NA | 1.1 | 89.1 | 56.5 | 3.29 | 1.32 | O | |
15 U | NA | 12.5 | 79.2 | 58.3 | 4.00 | ND | O | |
16 S | C, RD | 0 | 92.9 | 92.9 | 3.50 | 1.57 | O | |
17 U | NA | 7.5 | 79.1 | 64.2 | 6.09 | 0 | O | |
18 U | NA | 42.0 | 88.0 | 94.0 | 4.17 | 1.91 | O | |
19 U | NA | 17.0 | 85.1 | 59.6 | 1.74 | 4.97 | O | |
20 U | NA | 10.3 | 92.3 | 92.3 | 2.29 | 1.13 | O | |
21 S | Pr | 23.5 | 94.1 | 70.6 | 0.71 | 1.31 | B | |
22 S | Pr, RD, An | 33.3 | 92.6 | 55.6 | 1.13 | 2.33 | B | |
23 U | NA | 29.6 | 77.8 | 77.8 | 1.50 | 3.74 | O | |
NmRTSCTR | 1 U | NA | 13.8 | 100 | 43.1 | 0.58 | 2.34 | O |
2 U | NA | 8.9 | 91.1 | 48.2 | 3.15 | 1.76 | ND | |
3 S | RD | −13.2 | 89.5 | 42.1 | 1.58 | 1.71 | O | |
4 S | C, RD | 6.3 | 100 | −66.7 | 0.48 | 1.89 | A | |
5 U | NA | −23.6 | 94.4 | 28.3 | 2.33 | 1.31 | O | |
NmSTSCTS | 29 S | Pr, An | 100 | 82.5 | 90.2 | 1.43 | 2.45 | B |
30 U | NA | 56.0 | 100 | 100 | 0.69 | ND | A | |
31 U | NA | 56.1 | 100 | 63.4 | 0.82 | 1.51 | B | |
NmSTSCTR | 26 S | Pr | 75.2 | 96.0 | 30.2 | 3.51 | 1.63 | O |
27 U | NA | 100 | 100 | 31.5 | 0.73 | 2.35 | AB | |
28 U | NA | 58.0 | 81.3 | 38.6 | 1.76 | 0.86 | B | |
NmSTRCTR | Dd2 | 89.2 (10.2) | 47.6 (16.9) | 11.1 (30.5) | ||||
25 U | NA | 58.5 | 28.6 | 8.3 | 2.17 | 3.27 | ND | |
NmR TR CTS | 24 S | Pr | 16.0 | 28.0 | 100 | 0.25 | 1.76 | B |
Nm, neuraminidase; T, trypsin; CT, chymotrypsin; S, sensitive; R, resistant.
Each field isolate designation includes a label to indicate whether the isolate was derived from a child with uncomplicated (U) or severe (S) malaria. Laboratory strains 7G8 and Dd2 are indicated in italics. For the laboratory strains, the means (and standard deviations) of results from three experiments are shown. Field isolate data are from a single experiment for each isolate. Field isolates corresponding to infections with the indicated number of genotypes are as follows: one genotype, isolates 8, 21, 22, and 26; two genotypes, isolates 2, 11, 12, and 13; three genotypes, isolates 9 and 23; four genotypes, isolates 5 and 14. Other isolates were not genotyped.
Severe malaria was indicated by a comatose state (C), respiratory distress (RD), prostration (Pr), and anemia (An). For the uncomplicated malaria cases, NA indicates not applicable.
Percentages of inhibition of invasion are relative to the level of invasion of non-enzyme-treated control erythrocytes. A result of 100% inhibition indicates that no rings of infected erythrocytes were counted, whereas a negative percentage of inhibition (e.g., −32%) indicates an increase in invasion compared to the control.
These results have been published previously in more detail (5). PMR, parasite multiplication rate; SI, selectivity index.
For two samples, the corresponding ABO type was not determined (ND).