Table II.

Antisera Against Plasmodium falciparum Normocyte Binding Proteins Inhibit Merozoite Invasion of Trypsinized RBCs

PF strainTreatmentPrebleedNBP1NBP2 (S3)NBP2aNBP2b
FVONone106 ± 7102 ± 15107 ± 25114 ± 4104 ± 7
FVOTrypsin107 ± 745 ± 265 ± 265 ± 168 ± 12
HB3None94 ± 2100 ± 1110 ± 13104 ± 1795 ± 1
HB3Trypsin96 ± 369 ± 1745 ± 1566 ± 1426 ± 10
MC KNone118 ± 1894 ± 5139 ± 7NDND
MC KTrypsin122 ± 760 ± 1243 ± 6NDND
3D78None95 ± 750 ± 151 ± 357 ± 770 ± 6
  • Purified schizonts were incubated with untreated erythrocyte or trypsin-treated erthrocytes (T) in the presence of purified IgG. IgG was added at 1 mg/ml and invasion rates are expressed as a percentage of invasion in the absence of any IgG, with standard error.