Human small intestinal epithelial cells (H4) were introduced into inserts in 12-well plates (Corning Transwell, 0.4 μm pore size, New York, USA) at concentration of 1 × 10 6 cells/mL. Transepithelial resistance (TER-Ω/cm 2 ) was measured periodically using Millicell-ERS Electrical Resistance System (Millipore, Bedford, USA) until values of about 1000 Ω/cm 2 were attained, such high values indicating maximum attainable polarity in H4 cells, as previously determined (results not shown). Rotavirus suspensions (at 1 × 10 7.5 /mL TCID 50 ) were mixed with T. esculentum extracts at below their predetermined IC 50 concentrations ( Table 2 ) and then introduced onto H4 monolayers in insert wells. Tylosema esculentum extracts diluted in DMEM, DMEM alone, and Combivir diluted in DMEM were introduced as respective controls. The effect of the extracts on the cell polarity was evaluated by measurement of transepithelial electrical resistance (TER) as previously described in [34] . TER values of monolayers exposed to combinations of marama/Combivir treatments, DMEM, and RV controls were plotted.