Phenotypic characterization of macrophages in the BMB sample of human acute leukemia

Macrophages within tissues display a strong plastic ability in respond to environmental cues in both physiologic influences and disease. However, the macrophage phenotype and its distribution in the bone marrow biopsies (BMB) samples of human acute leukemia (AL) remain poorly understood. In this study, 97 BMB samples of patients with acute leukemia and 30 iron-deficiency anemias (IDA) as control group were evaluated with immunohistochemistry. In comparison with controls, the counts of CD68⁺, CD163⁺, and CD206⁺macrophages were remarkably increased in BMB samples of acute leukemia (P < 0.01), as well as their infiltration density was roaring up-regulation (P < 0.01). The expression levels of CD68⁺, CD163⁺, and CD206⁺macrophages were decreased in patients with complete remission, but there still existed statistically significant contrast to the control group (P < 0.01). The ratios of the CD163-positive cells or CD206-positive cells to CD68-positive cells were most prevalent in the BMB samples of human acute leukemia compared with the control group (P < 0.01), which support that macrophages were polarized to M2 macrophages.