Table 1.
Sera characteristics.
Fig 1.
Alignment of BmR1 homologous proteins.
Amino acid alignment by MegAlign and percent identity to B. malayi BmR1 of the following BmR1 homologous proteins: W. bancrofti Wb-Bhp-1 (45%) and Wb-Bhp-2 (55%), O. volvulus Ov-Bhp-1 (41%), and L. loa Ll-Bhp-1 (42%). Amino acid residues conserved with BmR1 are shaded black.
Fig 2.
Characterization of BmR1 homologous proteins.
(A) SDS-PAGE and SimplyBlue SafeStain analysis of recombinant Wb-Bhp-1 (predicted 20.4 kD), Ov-Bhp-1 (predicted 27 kD), and Ll-Bhp-1 (predicted 26.5 kD). (B) Immunoblot analysis of Wb-Bhp-1, Ov-Bhp-1, Ll-Bhp-1 with anti-Xpress antibody, which targets the amino-terminal Xpress epitope of these recombinant proteins.
Fig 3.
Immunolocalization of BmR1 homologues.
This figure shows immunohistochemical results from worm sections that were processed as described in the Methods. A B. malayi female worm section stained with normal mouse sera showed no labeling (A). B. malayi female worm sections stained with anti-Wb-Bhp-1 demonstrated no staining in morula (B) or pretzel stage larvae (C) but staining of stretched Mf (DE). B. malayi L3 stage demonstrated minimal staining with normal mouse sera (F) and minimal staining in a diffuse pattern with anti-Wb-Bhp-1 sera (G). O. volvulus nodule stained with anti-Wb-Bhp-1 demonstrated staining of Mf within the nodule (H). Annotations: Mf (arrow), uterus (ut), and intestine (i), which has intrinsic alkaline phosphatase. Scale bar indicates 20 micrometers.
Fig 4.
Anti-Wb-Bhp-1 IgG4 ELISA sensitivity and specificity.
Graphs show the individual OD490 for the anti-Wb-Bhp-1 IgG4 ELISA. Median values are indicated by the black bar. Positivity cutoff of 0.2 is indicated by the dotted black line. PNG: Papua New Guinea. CDI: Côte d’Ivoire. (A) ELISA data for sera from people with the indicated filarial infection, or non-endemic controls (Table 1). Median ELISA data from each filarial infection are statistically different by Kruskal-Wallis test with p< 0.0001. (B) ELISA data from individuals with W. bancrofti infection from the specified country of origin. Median OD490 and overall percent positivity for each country are significantly different by Kruskal-Wallis, with p<0.0001.
Fig 5.
Anti-Wb-Bhp-1 IgG4 ELISA dependence on Mf count.
Graphs show the individual OD490 for the anti-Wb-Bhp-1 IgG4 ELISA. Median values are indicated by black bar. Positivity cutoff of 0.2 is indicated by the dotted black line. Data are color coded by country of origin for the sera. PNG: Papua New Guinea. CDI: Côte d’Ivoire. (A) OD490 titers plotted against the log of Mf count. Values are significantly correlated by Spearman, with r = 0.2982, p<0.0001. (B) OD490 titers from individuals with W. bancrofti infection from the specified country of origin stratified by log of Mf count. Median OD490 and overall percent positivity for each column are significantly different by Kruskal-Wallis, with p< 0.0001.
Fig 6.
Identification of human antibodies to Ov-Bhp-1 and Ll-Bhp-1.
(A) Representative immunoblot results for Ov-Bhp-1with sera from people with onchocerciasis. (B) Representative immunoblot analysis of Ll-Bhp-1 with sera from people with loiasis. Lanes 1 and 16 used anti-Xpress control antibody. Lanes 2–15 show immunoblot results with sera from people with the specified infection.