A band cell (also called band neutrophil, band form or stab cell) is a cell undergoing granulopoiesis, derived from a metamyelocyte, and leading to a mature granulocyte.

It is characterized by having a curved but not lobular nucleus.^[1]

The term "band cell" implies a granulocytic lineage (e.g., neutrophils).^[2]

Band neutrophils are an intermediary step prior to the complete maturation of segmented neutrophils. Polymorphonuclear neutrophils are initially released from the bone marrow as band cells. As the immature neutrophils become activated or exposed to pathogens, their nucleus will take on a segmented appearance. An increase in the number of these immature neutrophils in circulation can be indicative of an infection for which they are being called to fight against, or some inflammatory process. The increase of band cells in the circulation is called bandemia and is a "left shift" process.

Blood reference ranges for neutrophilic band cells in adults are 3 to 5% of white blood cells,^[3] or up to 0.7 × 10⁹/L.^[4]

An excess may sometimes be referred to as bandemia.

• Pluripotential hemopoietic stem cell

• 
  Band neutrophil in peripheral blood film
• 
  Hematopoiesis

• Histology image: 01807loa – Histology Learning System at Boston University - "Bone Marrow and Hemopoiesis: bone marrow smear, neutrophil series"
• Histology at KUMC blood-blood11
• Histology image: 75_07 at the University of Oklahoma Health Sciences Center
• Histology at okstate.edu
• Slide at hematologyatlas.com - "Neutrophil band" visible in second row
• Interactive diagram at lycos.es