TABLE 4.
HLMs and sulfated polysaccharides with inhibitory activity against merozoite invasion in growth inhibition assaysa
| Inhibitor [reference(s)] | % inhibition (SEM) |
|---|---|
| Very strong inhibitors | |
| Inulin sulfate | 93 (4.5) |
| De-N-Ac Hep (bovine)b | 92 (2.5) |
| Dextran sulfatec (40, 41) | 90 (0.3) |
| Xylan sulfated | 86 (6.4) |
| Propylene glycol alginic sulfate | 77 (3.6) |
| Chemically oversulfated N-Ac Hep | 72 (1.3) |
| De-N-Ac Hepb (porcine) | 72 (1.3) |
| De-N-Ac dermatan Sb | 67 (13.7) |
| Chemically oversulfated λ-carrageenanc (13, 42) | 65 (10.4) |
| Tragacanth sulfate | 64 (11.7) |
| Chemically oversulfated ι-carrageenan (13) | 64 (6.4) |
| Scleroglucan sulfate | 55 (8) |
| Strong inhibitors | |
| Cyclodextrin sulfate | 96 (2) |
| Welan sulfate | 96 (1.3) |
| Agarose sulfate | 95 (1.4) |
| Arabic sulfatee | 95 (1.6) |
| Glycogen sulfate | 95 (2.5) |
| Phenoxyacetyl cellulose sulfate | 95 (2.3) |
| Chemically oversulfated free amino Hep | 95 (2.5) |
| Konjac glucomannan sulfate | 95 (2.8) |
| Levan sulfate | 94 (3.2) |
| Pullulan sulfatec | 94 (1.2) |
| Taramind sulfate | 94 (1.5) |
| Ghatti sulfate | 92 (2.8) |
| λ-Carrageenane (13, 42) | 90 (2) |
| Paramylon sulfate | 90 (1.9) |
| Psyllium seed gum sulfate | 89 (2) |
| Stachyose sulfate | 89 (4.6) |
| Agarose sulfatec | 87 (2.6) |
| Chemically oversulfated κ-carrageenane (13, 42) | 85 (2.9) |
| Gellan sulfate (82) | 82 (9.6) |
| Amylopectin sulfate | 74 (1) |
| Tara sulfateb | 71 (3.7) |
| Heparin (bovine lung) (7) | 70 (8.1) |
| Guar sulfatec | 68 (7.1) |
| Alginic sulfate | 62 (11) |
| Psyllium sulfate | 56 (10) |
| Moderate inhibitors | |
| Dextrin sulfate | 56 (9.1) |
| Karaya sulfate | 97 (0.1) |
| Dextrin sulfate | 96 (0) |
| Fucogalactan sulfate | 96 (1) |
| Arabic sulfate | 94 (1) |
| Carboxymethyl cellulose sulfate | 94 (1.1) |
| Amylose sulfate | 86 (2.1) |
| Pectin sulfatec | 84 (2) |
| Locust bean gum sulfate | 79 (3.7) |
| Chitosan sulfate | 61 (2.7) |
| Guar sulfate | 59 (3.6) |
The compounds at 2, 10, and 20 μg/ml each were tested in growth inhibitory assays. Inhibitory compounds are listed according to their estimated IC50 and ordered on the basis of their inhibitory activity. Very strong inhibitors had estimated IC50s of <2 μg/ml, strong inhibitors had estimated IC50s of 2 to 10 μg/ml, and moderate inhibitors had estimated IC50s of 10 to 20 μg/ml. Inhibitory activity at 2 for very strong inhibitors, 10 for strong inhibitors, and 20 for moderate inhibitors (in μg/ml) is as indicated. Data are means ± SEMs from two assays performed in duplicate. Highly inhibitory compounds were additionally screened in invasion inhibition assays with purified merozoites to confirm targeting of merozoite invasion. Where published previously, the reference numbers are listed beside the compounds. Abbreviations: de-N-Ac, de-N-acetylated; Hep, heparin; N-Ac, N-acetylated.
The compounds were noninhibitory in invasion inhibition assays, suggesting that these samples may contain a nonspecific growth inhibitory substance or act through a mechanism separate to invasion inhibition.
Prepared using pyridine sulfur trioxide complex.
Xylan sulfate is also known as pentosan polysulfate.
Prepared using piperidine-N-sulfonic acid.