Effects of an anti-exospore monoclonal antibody on microsporidial development in vitro

Parasitology. 1998 Dec;117 ( Pt 6):515-20. doi: 10.1017/s0031182098003345.


In this study we evaluated the effects of the anti-microsporidial exospore monoclonal antibody 3B6, recognizing 3 Encephalitozoon species, Encephalitozoon intestinalis (Syn. Septata intestinalis), Encephalitozoon cuniculi, and Encephalitozoon hellem on microsporidial growth in vitro. Pre-treatment of spores for 24 h with mAb 3B6 resulted in 21-29% fewer infected host cells 4 days after inoculation of the cultures compared to cultures pre-treated with medium or an irrelevant isotype control mAb (P < 0.001). Fewer intracellular spores (1.2 +/- 0.2) in infected cells were found when mAb 3B6 was present in cultures compared to cultures with medium alone (4.3 +/- 0.8) or an irrelevant isotype control mAb (4.2 +/- 0.9; P < 0.001). This decrease appeared not to be dependent on time of exposure, mAb concentration, or presence of complement. It is concluded that antibodies, particularly those directed to potential neutralizing-sensitive epitopes on spores, may have a role in the control of microsporidial growth in vitro.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antibodies, Monoclonal / pharmacology*
  • Antibody Specificity
  • Chlorocebus aethiops
  • Complement System Proteins / pharmacology
  • Encephalitozoon / drug effects*
  • Encephalitozoon / growth & development
  • Encephalitozoon / immunology
  • Epitopes / drug effects
  • Fluorescent Antibody Technique
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Spores / drug effects
  • Time Factors
  • Vero Cells / parasitology


  • Antibodies, Monoclonal
  • Epitopes
  • Complement System Proteins