CXCL8 and infection: Other studies primarily focused on immunologic aspects such as the appearance of interleukins in the supernatant of invaded cells, showing increased expression of IL-8 due to infection [22] in a strain-dependent manner, as well as minor changes in the expressions of IL-1 and IL-4 in a time-dependent manner with a slight increase at the 1st and 4th hour and a subsequent decrease by the 24th hour following infection [23].