Immunophenotyping Flashcards
Alk
- expressed in t(2;5) anaplastic large cell lymphoma
- can be positive in IMT from multiple sites
bcl-1 (cyclin D1, PRADA-1)
- expressed in mantle cell lymphoma (nuclear staining)
- hairy cell leukemia and plasma cell neoplasm may also be positive
- breast and colon carcinoma are positive
bcl-2
- Reactive lymph nodes expressed by
- T cells
- mantle B cells
- small number of mantle B cells that normally permeate the follicle center (increased in follicular lysis)
- Also positive in
- most low grade B cell lymphomas and many high grade B cell lymphomas
- expression in follicular lymphoma decreases with grade
- >95% in grade 1 and 75% in grade 3
- not expressed in Burkitt lymphoma; helpful to separate Burkitt from Burkittlike lymphoma
bcl-6
- strongly expressed in normal germinal center B cells
- expressed in some lymphomas, including
- Burkitt lymphoma
- follicular lymphoma
- nodular lymphocyte predominant HL
- angioimmunoblastic T cell lymphoma
- subset of DLBCL
- ? anaplastic large cell lymphoma ?
CD1a
- expressed by
- Langerhans cells
- dendritic reticulum cells
- interdigitating reticulum cells
- cortical thymocytes
- Langerhans cell histiocytosis shows coexpression of S100 and CD1a
CD2
expressed by T and NK cells from a very early stage
CD3
- expressed by T cells (mature and nonneoplastic)
- noncovalent association with TCR
- composed of 3 chains: gamma, delta, and epsilon
- cytoplasmic expression may be present in immature T cells and NK cells, which lack surface CD3
CD4
- expressed by
- subset of T helper cells
- monocytes
- histiocytes
- dendritic cells
- normal CD4:CD8 in blood is 2-4:1
- CD4+/CD8+ T cells are normal only in thymus; otherwise probably neoplastic
- CD4-/CD8- T cells only normal in early T cell maturation
- most T cell neoplasms are CD4+
CD5
- expressed by
- normal T cells
- small number of B cells
- not expressed by NK cells
- CD5 coexpression in B cells is hallmark of SLL/CLL and MCL
- sometimes lost in T cell neoplasms
- expressed in most thymic carcinomas
CD7
- expressed by both T cells and NK cells
- CD7 loss is often seen in T cell neoplasms, especially cutaneous T cell lymphoma
- sometimes expressed in myeloblasts (M4 and M5 types)
CD8
- expressed by CD4- T cells
- often expressed in neoplastic NK, T cytotoxic and T suppressor cells
CD10 (CALLA)
- expressed by
- normal and neoplastic follicle center cells
- normal granulocytes
- follicular lymphoma (less so with higher grade)
- NLPHL
- angioimmunoblastic T cell lymphoma
- most B cell ALL
- often in plasma cell neoplasms
- nonhematolymphoid tumors
- RCC
- endometrial stromal sarcoma
- HCC (canalicular pattern)
CD11b (MAC-1)
- normally expressed by monocytes and granulocytes
- positive in hairy cell leukemia
- AML with inv(16) or t(16;16)
- AML with t(9;11)
- Acute myelomonocytic leukemia
- Acute monocytic/monoblastic leukemia
CD11c (C3r)
- normally expressed by monocytes and granulocytes
- strongly positive in hairy cell leukemia
- expressed weakly in CLL
- negative in MCL
CD13
- expressed by granulocytes and precursors
- expressed in nearly all types of AML
- may be weakly expressed in ALL
CD14
- expressed by monocytes
- variably expressed in AML with monocytic/monoblastic differentiation
- AML with t(9;11)
- AML with inv(16)
- Acute myelomonocytic leukemia
- Acute monocytic/monoblastic leukemia
CD15 (Leu-M1)
- expressed in
- mature monocytes and granulocytes
- RS cells
- most adenocarcinomas
- negative in ALCL
- in AML, CD15 indicates a maturing phenotype
CD16
expressed by normal and neoplastic NK cells and granulocytes
CD19
- expressed by
- B cells from pro/pre B stage onward
- normal plasma cells, but lost in neoplasm
- dim in follicular lymphoma
- some myeloblasts, especially AML with t(8;21)
CD20
- expressed on surface of mature B cells
- not expressed by plasma cells
- usually not expressed in classic HL (positive in 20%)
- NLPHL is uniformly positive
- dim in CLL
- FMC-7 is an antibody that recognizes a particular epitope of CD20
- cells with weak CD20 (CLL) tend to be FMC-7 negative
- cells with bright CD20 tend to be FMC-7 positive (e.g., most other B-NHLs)
CD23
the IgE receptor
- positive in CLL
- negative in MCL
- often positive in FL
CD25
IL-2 receptor
- expressed by
- activated lymphoid cells (T&B)
- hairy cell leukemia
- adult T cell leukemia (ATCL)
- soluble IL-2 receptor is usually elevated also
- expression in mast cells indicates KIT rearrangement and clonality
CD30
- Ki-1; Ber-H2
- expressed by
- normal plasma cells
- immunoblasts
- NK cells
- RS cells
- ALCL
- embryonal carcinoma
- mediastinal B cell lymphoma
CD33
expressed by normal and neoplastic myelomonocytic cells
CD34
- expressed by
- normal and neoplastic endothelial cells
- immature hematolymphoid cells
- GIST
- DFSP
- SFT
CD38
- expressed by
- activated T and B cells
- plasma cells
- B, T, and plasma cell neoplasms
- expression in CLL is (like ZAP-70) indicative of IgVH nonmutated status and a more aggresive clinical course
CD41 and CD61
- expressed by normal and neoplastic megs
CD43
- expressed by normal and neoplastic T cells
- underexpressed in WAS
- anomalously expressed on B cells in MCL, SLL, and some MZL (especially MALT)
- not expressed in FL
CD45 (LCA)
- present in nearly all normal and neoplastic leukocytes
- as they differentiate CD45 expression by hematolymphoid cells changes, with
- mature lymphs and monocytes having bright expression
- granulocytes intermediate expression
- erythrocytes almost negative
- blasts are dim to negative CD45
- plasma cells are dim to negative CD45
- Not expressed by RS cells
CD45-RO (UCHL-1)
- expressed by normal and neoplastic T cells
CD56
- expressed by
- normal and neoplastic NK cells
- neuroepithelial cells (small cell CA)
- plasma cell neoplasms
- can be positive in AML with t(8;21)
- absent in plasmablastic lymphoma
CD57 (Leu-7)
expresed by a subset of normal and neoplastic NK cells and neuroepithelial cells
CD59
- present on nearly all human cells
- decreased (along with CD55/DAF) in PNH
CD68
- expressed by macrophages and histiocytes, but its specificity is poor
CD71
- aka, transferrin receptor
- expressed in
- highly metabolic cells
- higher levels correlate with tumor grade in hematolymphoid neoplasms
CD79a
- expressed by normal and neoplastic B cells and plasma cells
- negative in RS cells
CD99 (p30/32, mic-2; O-13)
- expressed in
- ALL
- PNET/Ewing
- granulosa cell tumors
- synovial sarcoma
- RMS
- SFT
CD103
sensitive and specific marker for hairy cell leukemia
CD117 (c-kit)
- expressed by
- interstitial cell of Cajal (the precursors of GIST)
- melanocytes
- seminoma
- progenitor myeloid cells (AML, CML)
- mast cells
CD138
- plasma cell marker
- specific among hematolymphoid neoplasms for plasma cells, but is positive in a wide range of epithelial and mesenchymal tumors
Clusterin
- expression in a discrete Golgi pattern in ALCL
- strong cytoplasmic reactivity in megs
EMA
- expressed by
- plasma cells
- ALCL
- NLPHL
- PEL
- T cell rich B cell lymphoma
fascin
- expressed by RS cells and dendritic reticulum cell
HLA-DR
- expressed by
- monocytes
- B cells
- activated T cells
- positive in B-ALL/LBL and most myeloblasts
- negative in T-ALL and APML
PAX5
- nuclear expression in B cell neoplasms and classic HL
- negative in T cell neoplasms and plasma cell neoplasms
- may be positive in Merkel cell carcinoma and small carcinoma of the lung
S100
- expressed in nuclear and cytoplasmic compartments
- expressed by
- neural and neural crest tissues
- glial cells
- Schwann cells
- melanocytes
- sustentacular cells of adrenal medulla
- chondrocytes
- adipocytes
- myoepithelial cells
- subset of histiocytes
- interdigitating reticulum cells
- dendritic reticulum cells
- Langerhans cells
- neural and neural crest tissues
ZAP-70
- normally expressed primarily by T and NK cells
- expressed in subset of CLL, B-ALL, and most T cell neoplasms
- expression in CLL correlated with unmutated IgVH status and a more aggressive course
CD34 and HLA-DR are negative in
- AML with t(15;17)
- AML with t(1;22)
- +/- in acute megakaryoblastic leukemia