Immunodeficient mice are neutropenic. (A) White blood cell (WBC) counts in normal (□) and nude (▪) mice. (B) Differential cell counts in normal (□) and nude (▪) mice peripheral blood. (C,D) WBC and differential cell counts in normal (□) and SCID (▦) mice peripheral blood. Band neutrophil (Band), segmented neutrophil (Segm), lymphocyte (Lymph), and monocyte (Monoc) counts are shown. Error bars indicate SEM for 15 animals individually analyzed. *P < .001.