FIG. 6.

Differential interaction of T. cruzi metacyclic-stage surface molecule gp30 and 82 with gastric mucin. (A) Gastric mucin at 20 mg/ml was added to HeLa cells 15 min before they were incubated with metacyclic trypomastigotes. After a 1-h incubation, the cells were washed, fixed, and stained for intracellular parasite counting. The values are the means and SD of three experiments performed in duplicate. (B) J18, the recombinant gp82, or purified gp30 at 10 μg/ml was added to microtiter plates coated with porcine gastric mucin. After being washed, the plates were sequentially incubated with anti-J18 antibody and anti-mouse immunoglobulin conjugated to peroxidase. The bound enzyme was revealed using o-phenylenediamine. The values are the means and SD of triplicate samples. O.D.₄₉₂, optical density at 492 nm.