Immature neutrophils versus monocyte

Band versus mono

In this image from dog blood, there are two immature neutrophils – one a band neutrophil (lower left) and the other a metamyelocyte (arrowhead) with a kidney-bean shaped nucleus and the same cytoplasm as the band neutrophil. A monocyte is also evident and differs from the two immature neutrophils by a more uniformly blue-gray cytoplasm, discrete margined cytoplasmic vacuoles and lighter chromatin (less heterochromatin). In contrast, the two immature neutrophils resemble each other (nuclear, cytoplasm features) more than they resemble the monocyte. Both are toxic, with cytoplasmic basophilia and toxic granulation, indicating an inflammatory leukogram. This dog actually had a degenerative left shift (more bands than mature neutrophils).