Cord-to-mother IgG transfer according to placental malaria.

<p>CIRC: maternal peripheral blood at delivery; CORD: cord blood, ln(CORD/CIRC): ratio representing the transfer of maternal IgG to the neonate at birth; * <0.05; ** ≤0.01; *** ≤0.001.</p

Increased persistence of maternally derived malaria-specific IgG3 among young infants born to women with the IgG3-H435 allele compared to those homozygous for IgG3-R435.

<p>The odds ratio (± 95% confidence interval) of maternal malaria-specific IgG3-H435 persistence at 6 months relative to homozygous IgG3-R435 based on dichotomized cord-to-mother transfer ratio (over or below the median) using multivariate regression analysis adjusted for the variables shown in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1002403#pmed.1002403.t001" target="_blank">Table 1</a>. To reduce the possibility that IgG3 was produced by malaria-infected infants, samples from any infant showing an increase in malaria-specific IgG3 between 0 and 3 months or between 3 and 6 months of age (any antigen) were removed from the analysis (<i>N =</i> 195). The odds ratio was obtained after adjustment for malaria-specific IgG3 in maternal peripheral blood (see <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1002403#pmed.1002403.t003" target="_blank">Table 3</a>). Of 302 infants, between 3 and 11 had missing data (according to the tested antigen) and were not included in the analysis (see details in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1002403#pmed.1002403.t003" target="_blank">Table 3</a>). There was no collinearity between all tested variables, and variance inflation factor (VIF) values were all ≤2.17.</p

Association between cord-to-mother ratio (CMTR) and factors that could influence transplacental transfer: Placental malaria, maternal total IgG, and maternal malaria-specific IgG3.

<p>Association between cord-to-mother ratio (CMTR) and factors that could influence transplacental transfer: Placental malaria, maternal total IgG, and maternal malaria-specific IgG3.</p

Persistence of malaria-specific IgG3 at 6 months of age related to level of maternal anti-malaria IgG3.

<p>Persistence of malaria-specific IgG3 at 6 months of age related to level of maternal anti-malaria IgG3.</p

The cumulative number of malaria infections recorded from birth to 12 months of age.

<p>The cumulative number of malaria infections recorded from birth to 12 months of age.</p

Maternal IgG3-H435 polymorphism is associated with a decreased risk of symptomatic malaria in infants from birth to 12 months of age.

<p>The time to first symptomatic malaria episode during infancy is shown. The log-rank analysis yielded <i>p =</i> 0.102. The Cox proportional hazard analysis adjusted for malaria exposure and placental malaria gave a hazard ratio of 0.69 (95% CI 0.46, 1.05, <i>p =</i> 0.083).</p

Population characteristics according to the IgG3 polymorphism at position 435.

<p>Population characteristics according to the IgG3 polymorphism at position 435.</p

Increased transplacental transfer of GLURP-R2-specific IgG3 is associated with delayed time to first symptomatic malaria.

<p>Dichotomized cord-to-mother transfer ratio (above or below the median; <i>N =</i> 493 infants). The log-rank analysis yielded <i>p <</i> 0.001, and the Cox proportional hazard analysis model adjusted for malaria exposure and placental malaria gave a hazard ratio of 0.59 (95% CI 0.45, 0.77, <i>p <</i> 0.001).</p

The cord-to-mother transfer ratio of malaria-specific IgG1, IgG3-R435, and IgG3-H435.

<p>(A) The cord-to-mother transfer ratios (CMTRs) are represented: malaria-specific IgG1 (orange bars), IgG3 for women with the IgG3-H435 allele (dark blue bars, <i>N =</i> 120), and IgG3 for women homozygous for the IgG3-R435 allele (light blue bars, <i>N =</i> 377). Statistical comparison with IgG1 was performed for 377 women homozygous for IgG3-R435 and 120 women with the IgG3-H435 allele. Data are shown as box and whisker plots, and the <i>p-</i>values of the logistic regression univariate analysis are represented as follows: ** <i>p</i> ≤ 0.007, *** <i>p</i> ≤ 0.001. Only <i>p-</i>values ≤ 0.007 were considered significant after Bonferroni correction for multiple comparisons. (B) A multivariate logistic regression was performed to test whether individuals with IgG3-H435 had greater CMTR (over or below the median) relative to those with only IgG3-R435. The association is represented by the odds ratio (± 95% confidence interval) for each malaria antigen. Adjusted variables are shown in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1002403#pmed.1002403.t001" target="_blank">Table 1</a>. There was no collinearity between all tested variables, and variance inflation factor (VIF) values were ≤ 1.08.</p