The use of HemaCare-sourced macrophages has been cited in a recent publication in the Journal of Immunology. The paper is a collaboration between the University of Maryland in College Park, and biopharmaceutical company AstraZeneca. 
The role of macrophages in the human immune system is not nearly as well-known as T cells or B cells, which are seemingly ubiquitous in the cell and gene therapy field. Like lymphocytes, macrophages are derived from hematopoietic stem cells. Unlike the lymphoid lineage, however, myeloid precursors ultimately produce in the macrophage an immune cell capable of both antigen presentation and phagocytic activity.