TABLE 1

MBL-dependent neutralizing activity in sera with known polymorphisms in the MBL2 gene

Donor no.Polymorphisms in the MBL2 geneaSerum MBL level (ng/ml)bSerum MBL binding to DENV (OD at 450 nm)c% neutralization of DENVd
12 HYPA/LXPA 3,5520.209 ± 0.04373.6 ± 11.1
13 HYPA/LXPA 2,1210.164 ± 0.04932.3 ± 14.1
14 LYQA/LYQC 2190.037 ± 0.01421.4 ± 13.7
15 LYPB/HYPD <20.005 ± 0.00316.9 ± 11.0
16 HYPD/HYPD <20.019 ± 0.01811.9 ± 1.5
  • a  Single-nucleotide polymorphisms (SNPs) in the MBL2 gene include the following: G-to-C nucleotide substitutions at positions −550 (alleles H/L) and −221 (alleles X/Y) in the promoter region; C-to-T nucleotide substitution at position +4 (alleles P/Q) in the 5′ noncoding region; single-nucleotide substitutions at codons 52 (C to T [allele D]), 54 (G to A [allele B]), and 57 (G to A [allele C]) in exon 1. The normal allele is referred to as A.

  • b  Serum MBL levels were measured by a quantitative capture ELISA as described in Materials and Methods.

  • c  Serum MBL binding to insect cell-derived DENV-2 virions was determined using a capture ELISA as described in the legend to Fig. 5D. Data are the means ± standard deviations (SD) for four independent experiments.

  • d  MBL dependent-serum neutralization of insect cell-derived DENV-2 was performed as described in the legend to Fig. 5E. Neutralization was calculated based on reduction of the number of plaques compared to the value for heat-inactivated serum. Data are the means ± SD for three independent experiments.