CD33 and infection: Two days of exposure of PBMCs to GM-CSF plus paired Toll-like receptor agonists (resiquimod and lipopolysaccharide – LPS) to simulate a life-threatening infection, results in upregulated co-stimulatory molecules and CD11c expression on the CD33+ myeloid subpopulation, which is capable of processing synthetic long peptides from tumor-associated Ags.