Primary Hematopoietic and Lymphoid Tissue ›› Bone Marrow ›› Normal

Mature B-cells






Microscopic Features:
  • Slightly (1.5x) larger than a mature RBC
  • High nuclear to cytoplasmic ratio but with
  • Round mature Nucleus (clumped chromatin)
  • Nucleoli are absent
  • Cytoplasm is scant, light blue and lacks granules
Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
  • PB: **** (2nd most common lymphocyte in blood after T-cells)
  • BM: Rare scattered
  • LN: Mainly distriibuted in Follicular areas (Germinal Center and Mantle zone)
May Resemble:
  • Mature T-cells (can't distinguish T-cell and B-cell based on morphology)
  • Reactive lymphocyte
  • Monocyte
Differential Diagnoses:

If increased in blood, Lymph node or bone marrow:
Infection
Neoplastic (mature B-cell lymphoma or leukemia such as CLL)

Classic Immunophenotype:
  • CD19+
  • CD20+
  • CD22+
  • TdT-
  • CD34-
Cartoon Image:



Misc:
  • Morphologically you cannot distinguish mature T-cells from mature B-cells