Owing to the fact that, in their assays, the sequence of the stimuli was important (first chemokine stimulation, then LPS stimulation), the authors suggested that CCL2 can prime macrophages to respond to a subsequent signal, which corresponds well with CCL2's ability to prime myeloid cells described in CCL2 Primes Cells to Respond to Subsequent Infection of this review (128). This evidence concerns the gene CCL2 and infection.