Article
Extended Data Fig. 8 | Comparing parasite invasion and biomechanical
properties of frozen and fresh RBCs. a, The invasion efficiency of
P. falciparum laboratory strain 3D7 was compared across frozen and fresh
RBCs (n = 6 frozen and n = 14 non-Dantu, 12 Dantu-heterozygote and 12
Dantu-homozygote fresh biologically independent RBC samples per genotype
group). The percentage of parasitized RBCs that successfully invaded each
genotype group was measured using a f low-cytometry-based invasion assay.
Boxplots indicate the median (middle line) and interquartile ranges (top and
bottom of boxes) of the data; whiskers denote the total data range. Statistical
comparison across the three genotype groups was performed using one-way
ANOVA; pairwise comparisons between genotype groups were performed
using Tukey’s HSD test, with significant differences in 3D7 invasion observed
in frozen RBCs (non-Dantu versus Dantu homozygote, P = 0.001) and in
fresh RBCs (non-Dantu versus Dantu homozygote, P = 0.001). *P < 0.05;
**P < 0.01. b, Membrane f lickering spectrometry enabled measurement of RBC
biomechanical properties (bending modulus, tension, radius and viscosity) of
fresh (n = 53) and frozen (n = 51) RBCs from the same donor. No statistically
significant differences were detected between the two conditions for all of the
measured biophysical properties. Pairwise comparisons were performed using
a two-sided Mann–Whitney U-test; bending modulus, P = 0.1; tension, P = 0.6;
radius, P = 0.7; viscosity, P = 0.6.