Species-Specific Serological Detection for Schistosomiasis by Serine Protease Inhibitor (SERPIN) in Multiplex Assay

PLoS Negl Trop Dis. 2015 Aug 20;9(8):e0004021. doi: 10.1371/journal.pntd.0004021. eCollection 2015.

Abstract

Background: Both Schistosoma mansoni and Schistosoma haematobium cause schistosomiasis in sub-Saharan Africa. We assessed the diagnostic value of selected Schistosoma antigens for the development of a multiplex serological immunoassay for sero-epidemiological surveillance.

Methodology/principal findings: Diagnostic ability of recombinant antigens from S. mansoni and S. haematobium was assessed by Luminex multiplex immunoassay using plasma from school children in two areas of Kenya, endemic for different species of schistosomiasis. S. mansoni serine protease inhibitor (SERPIN) and Sm-RP26 showed significantly higher reactivity to patient plasma as compared to the control group. Sm-Filamin, Sm-GAPDH, Sm-GST, Sm-LAP1, Sm-LAP2, Sm-Sm31, Sm-Sm32 and Sm-Tropomyosin did not show difference in reactivity between S. mansoni infected and uninfected pupils. Sm-RP26 was cross-reactive to plasma from S. haematobium patients, whereas Sm-SERPIN was species-specific. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. ROC analysis for Sm-RP26, Sm-SERPIN and Sh-SERPIN showed AUC values of 0.833, 0.888 and 0.947, respectively. Using Spearman's rank correlation coefficient analysis, we also found significant positive correlation between the number of excreted eggs and median fluorescence intensity (MFI) from the multiplex immunoassays for Sm-SERPIN (ρ = 0.430, p-value = 0.003) and Sh-SERPIN (ρ = 0.433, p-value = 0.006).

Conclusions/significance: Sm-SERPIN is a promising species-specific diagnostic antigen. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. SERPINs showed correlation with the number of excreted eggs. These indicate prospects for inclusion of SERPINs in the multiplex serological immunoassay system.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Helminth / blood
  • Antibodies, Helminth / immunology
  • Antigens, Helminth / blood*
  • Antigens, Helminth / genetics
  • Antigens, Helminth / immunology
  • Cross Reactions
  • Cross-Sectional Studies
  • Female
  • Humans
  • Immunoassay / methods*
  • Kenya
  • Male
  • Molecular Sequence Data
  • Schistosoma haematobium / genetics
  • Schistosoma haematobium / immunology*
  • Schistosoma haematobium / isolation & purification
  • Schistosoma mansoni / genetics
  • Schistosoma mansoni / immunology*
  • Schistosoma mansoni / isolation & purification
  • Schistosomiasis haematobia / blood
  • Schistosomiasis haematobia / diagnosis*
  • Schistosomiasis haematobia / parasitology
  • Schistosomiasis mansoni / blood
  • Schistosomiasis mansoni / diagnosis*
  • Schistosomiasis mansoni / parasitology
  • Serine Proteinase Inhibitors / blood*
  • Serine Proteinase Inhibitors / genetics
  • Serine Proteinase Inhibitors / immunology
  • Serpins / blood*
  • Serpins / genetics
  • Serpins / immunology
  • Species Specificity

Substances

  • Antibodies, Helminth
  • Antigens, Helminth
  • Serine Proteinase Inhibitors
  • Serpins

Grants and funding

This work was supported by the Program for the Strategic Promotion of International Cooperation to Accelerate Innovation in Developing Countries, Funds for integrated promotion of social system reform and research and development by MEXT (Ministry of Education, Sport, Culture, Science and Technology) of Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.