*2.4. Viability of E. histolytica Trophozoites*

Trophozoites (~1 × <sup>10</sup>6/mL) were incubated with *L. acidophilus* (~1 × <sup>10</sup>9/mL) in serum-free Diamond's TYI S-33 medium for 120 min at 37 ◦C with agitation (200 rpm) in a thermoshaker (ALS-MS-100, Hangzhou Allsheng Instrument, Hangzhou, China). The viability of trophozoites was determined by the eosin dye exclusion method [6].
