Fig. 3.

Cryptosporidium parvum infection inhibits Cl⁻/${\text{HCO}}_3^{-}$ exchange activity. Postconfluent Caco-2 monolayers grown on 24-well plastic supports were treated with 0.5 × 10⁶ sporozoites/well for 24 h. DRA function (Cl⁻/${\text{HCO}}_3^{-}$ exchange activity) was measured as DIDS-sensitive (600 μM) ¹²⁵I⁻ uptake for 5 min. Results are expressed as nmol·mg protein⁻¹·5 min⁻¹ and represent means ± SE of 3 separate experiments performed in triplicate. *P < 0.05, compared with control.