Figure 1. Studied Leukocyte Subpopulations.
Color-coded diagram of the cell types analyzed by flow cytometry with arrows depicting the hierarchical levels of separation of circulating cell populations (leukocytes) and constituent subsets of the two main arms, innate and adaptive, of the immune system. Innate cell types, which provide prompt but generic responses to aggressors, include granulocytes (yellow), monocytes (pale blue), and dendritic cells (red). Adaptive cell types, which provide highly specific responses to microbial targets and may maintain a “memory” that enables a faster and greater response to previously encountered pathogens, include B cells (magenta) and T cells (green). The natural killer cells (orange) share features of both arms of the immune system. The name and, when relevant, the identifying marker are indicated beside each population. Cells inside a light-blue rectangle were phenotypically characterized with the antigen pointed to by the adjacent light-blue arrow; for example, the six CD3+ subsets (CD4− CD8−, CD4+, CD4+ CD8 dim, CD4+ CD8br, CD8br, and CD8 dim) are shown within a blue rectangle and were further subdivided into naive, central memory, effector memory, and terminally differentiated cells. The red rectangle indicates that the included cell populations have been jointly analyzed for CD39, the marker indicated by the red arrow. For simplicity, 45 of the 95 analyzed cell types, described in the full text, are shown. See also Figure S1 and Table S1.