KLF4 and atherosclerosis: In the absence of myeloid Klf4, TAMs had reduced expression of surface mannose receptor and Fizz1. Although classic M1 markers such as Nos2 and Tnfα were not increased, microarray analysis revealed activation of pathways associated with pro-inflammatory states, as well as the expression of a subset of mRNAs associated with macrophage activation in atherosclerosis.