| Резюме: | <p>Dantu erythrocytes, which express a hybrid glycophorin B/A protein, are protective against severe malaria. Recent studies have shown that Dantu impairs <em>Plasmodium falciparum</em> invasion by increasing erythrocyte membrane tension, but its effects on pathological host–parasite adhesion interactions such as rosetting, the binding of uninfected erythrocytes to <em>P. falciparum</em>–infected erythrocytes, have not been investigated previously. The expression of several putative host rosetting receptors—including glycophorin A (GYPA), glycophorin C (GYPC), complement receptor 1 (CR1), and band 3, which complexes with GYPA to form the Wright<sup>b</sup> blood group antigen—are altered on Dantu erythrocytes. Here, we compare receptor expression, and rosetting at both 1 hour and 48 hours after mixing with mature trophozoite-stage Kenyan laboratory–adapted <em>P. falciparum</em> strain 11019 parasites in Dantu and non-Dantu erythrocytes. Dantu erythrocytes showed lower staining for GYPA and CR1, and greater staining for band 3, as observed previously, whereas Wright<sup>b</sup> and GYPC staining did not vary significantly. No significant between-genotype differences in rosetting were seen after 1 hour, but the percentage of large rosettes was significantly less in both Dantu heterozygous (mean, 16.4%; standard error of the mean [SEM], 3.2) and homozygous donors (mean, 15.4%; SEM, 1.4) compared with non-Dantu erythrocytes (mean, 32.9%; SEM, 7.1; one-way analysis of variance, <em>P =</em> 0.025) after 48 hours. We also found positive correlations between erythrocyte mean corpuscular volume (MCV), the percentage of large rosettes (Spearman’s r<sub>s</sub> = 0.5970, <em>P =</em> 0.0043), and mean rosette size (r<sub>s</sub> = 0.5206, <em>P =</em> 0.0155). Impaired rosetting resulting from altered erythrocyte membrane receptor expression and reduced MCV might add to the protective effect of Dantu against severe malaria.</p>
|
|---|