Killing of Escherichia coli by Crohn’s Disease Monocyte-derived Macrophages and Its Enhancement by Hydroxychloroquine and Vitamin D Background: Crohn’s disease (CD) is associated with defective innate immunity, including impaired neutrophil chemotaxis, and mucosal invasion by bacteria, particularly adherent and invasive Escherichia coli that replicate inside macrophage phagolysosomes. We compared CD and healthy control (HC) macrophages for their abilities to...