Secondary Lymphoid Tissues ›› Lymph Node ›› Normal

Normal Lymph Node*






Microscopic Features:
  • An encapsulated lymphoid tissue (as opposed to Mucosa Associated Lymphoid Tissue, also known as MALT)
  • Comprised of follicles (primary and secondary) and interfollicular areas
  • B-cells mostly reside in the follicles while T-cells mostly reside in between the follicles (interfollicular areas)
  • Most of the follicles are located within the cortex
Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
  • PB: N/A
  • BM: N/A
  • LN: N/A
May Resemble:
  • Non-neoplastic Lymphadenitis
  • Follicular Lymphoma
Differential Diagnoses:

Reactive lymphoid hyperplasia
Infectious Lymphadenitis
Follicular Lymphoma

Classic Immunophenotype:
  • "T"-cells have the "Tiny" CDs: CD2, CD3, CD4, CD5, CD7, CD8
  • "B"-cells have the "Bigger" CDs: CD19, CD20, CD22
Cartoon Image:



Misc:
  • In a normal lymph, the primary follicles (not antigen stimulated and no germinal center) and secondary follicles (antigen stimulated with a germinal center) are where most B-cell reside The interfollicular (between follicles) areas are where most T-cells reside In summary: B-cells mostly reside in the follicles while T-cells mostly reside in between the follicles (interfollicular areas)