The innate immune system is composed of cells such as neutrophils, mast cells, and myeloid cells including microglia and macrophages that recognize conserved motifs of invading pathogens or molecules that indicate cellular stress. Specifically, the myeloid arm of the innate immune system is composed of cells of the myeloid lineage that take up residence in many tissues, including circulating monocytes in the blood, Langerhans cells in the skin, Kuppfer cells in the liver, and microglia in the CNS. Collectively, these cells are referred to as the mononuclear phagocyte system (MPS). Monocytes in these different organs have multiple roles, they can be pro- or anti-inflammatory depending on the context, present antigen to stimulate adaptive immunity, clear away cell debris, and prevent autoimmune responses to this debris. However, despite the promise of this system to clear protein aggregates or cellular debris, there have been recent, spectacular, and expensive failures to ameliorate neurodegeneration by manipulating this process, perhaps reflecting a lack of understanding of the MPS. As a primary manufacturer, Creative Biomart provides recombinant proteins of several sources, grades and formulations for research applications about myeloid cell.