CD19

A polyclonal antibody is now available that works on paraffin sections2. This antibody was raised against a synthetic peptide sequence corresponding to the cytoplasmic region of CD19.

Immunohistochemical expression

This protein is expressed through B lineage development, although downregulated in the terminal differentiation of plasma cells. Using the polyclonal antibody, B-cells of germinal centres and mantle zones stain strongly, with scattered cells staining in the interfollicular areas2. In the spleen, B-cells of marginal zone, germinal centres and mantle zones stain2. Plasma cells also stain, although sometimes weakly. Most plasma cells in the bone marrow are negative2. T-cells and macrophages are reliably negative.

It is reliably expressed by B lineage neoplastic cells, including leukaemias (B-ALL/B-LBL).

 

 

weakly positive

positive

 

B-lymphoblastic lymphoma

0/22

2/22

Small lymphocytic lymphoma

0/52

5/52

Mantle cell lymphoma

1/62

5/62

Follicular lymphoma

33/692

32/692

Burkitt's lymphoma

4/122

7/122

Marginal zone lymphoma

1/132

12/132

DLBCL

18/562

30/562

T-cell rich B-cell lymphoma

4/102

3/102

Mediastinal B-cell lymphoma

0/32

3/32

Post-transplant B-cell lymphoproliferative disease

1/42

0/42

Lymphoplasmacytic lymphoma

0/32

2/32

Hairy cell leukaemia

2/52

2/52

Plasmacytoma

0/62

0/62

Total

64/1942

103/1942

 

 

 

Classical Hodgkin lymphoma

1/102

0/102

Lymphocyte predominance Hodgkin lymphoma

2/72

0/72

 

 

 

T-lymphoblastic lymphoma

1/62

0/62

Peripheral T-cell lymphoma

0/182

0/182

Anaplastic large cell lymphoma

0/102

0/102

NK-cell lymphoma

0/32

0/32

Mycosis fungoides

0/12

0/12

T-cell CLL

0/12

0/12

Total

1/392

0/392

     

Diagnostic utility

References

1 Leong A S-Y, Cooper K and Leong FJ W-M. Manual of diagnostic antibodies for immunohistology. 2nd edition, 2003

2 Masir N, Marafioti T, Jones M, et al. Loss of CD19 expression in B-cell neoplasms. Histopathology 2006; 48:239-46

Last updated 18.2.06

SMUHT/PW Bishop