tonsil, appendix, and B-cell neoplasms
Regulatory status: IVD, FDA Class I
8516-C010: RTU, 10 capsules; 1 pack
8516-M250: RTU, 250 tests, 1 cartridge; 1 unit
CD19 regulates B-cell development, activation, and differentiation. CD19 is widely expressed from early pre-B-cells, normal B-cells, and normal plasma cells. Its expression on normal plasma cells is weaker than normal B-cells and a subpopulation may lack expression. CD19 is also expressed on follicular dendritic cells. CD19 is a specific and sensitive marker of B-cells and is found on the majority of B-cell neoplasms.
Strong membraneous staining is seen on the neoplastic cells of this pre-B-cell acute lymphoblastic leukemia (pre-B ALL).
A moderate to strong membraneous staining pattern for CD19 is seen on the neoplastic cells in this B-cell CLL/SLL.
This particular example of a plasmacytoma shows no staining reaction for CD19.