Hematopoietic and lymphoid cell subpopulations in Tcl1^-/--deficient and wild-type (Tcl1^+/+ and Tcl1^+/-) mice. Analysis of bone marrow B-lineage cells in Tcl1-deficient and wild-type mice was conducted by 3-color flow cytometric analysis of cells from both femoral and tibial bones (mean ± one standard error). Splenic marginal zone (MZ) cells were defined as CD19⁺CD21^hiCD23^int, follicular cells (FO) as CD19⁺CD21^intCD23^hi, and newly formed (NF) cells as CD19⁺CD21^loCD23^lo. Both B220 and CD19 antibodies stained splenic B cells similarly when used in combination with CD21 and CD23 antibodies. Each group included 7 to 10 mice 6 to12 weeks of age. Results expressed as mean plus or minus one standard error. Asterisks indicate statistically significant differences (P < .01, as assessed by Student t test) between Tcl1-deficient and wild-type mice.