Table I.

Shedding of EBA-175 at erythrocyte invasion occurs to the same extent whether or not it is used as the dominant invasion ligand

Proportion of rings reactive with anti–region VI
 antibodies in IFAa
P. falciparum lineErythrocyte pretreatment
untreatedmockneuraminidaseb
%%%
W2mef13.4 ± 3.8NDcNDc
3D716.7 ± 3.514.9 ± 3.215.4 ± 5.1d
  • a Figures shown are derived from three experiments. At least 1,000 rings were examined in each case. 95% confidence levels are indicated.

  • b Erythrocytes were neuraminidase treated or mock treated as described in Materials and methods. The efficiency of the treatment was assessed using an overlay assay to confirm lack of EBA-175 binding (Fig. S1, available at http://www.jcb.org/cgi/content/full/jcb.200604136/DC1).

  • c Invasion of neuraminidase-treated erythrocytes by W2mef was very inefficient (≤2.0% of invasion into mock-treated cells) as expected, so these rings were not examined by IFA.

  • d Invasion of neuraminidase-treated erythrocytes by 3D7 was 89% of invasion into mock-treated cells, in agreement with previous findings (Duraisingh et al., 2003).