Department

Immunology

EURO1

Preferred Sample Type

EUROclass B cell extended immunophenotyping

Suitable Specimen Types

Li Hep
EDTA Whole Blood

1 ml

Specimen Transport

No special requirements

Sample Processing in Laboratory

Sample should be stored between at room temperature (18C and 26C) prior to staining.

Turnaround Time

Up to 28 days

Sample Stability

Ideally EDTA sample should be <48 hours old and Li Hep <24 hrs old

EUROclass B cell extended immunophenotyping

General Information

Extended B cell immunophenotyping is used for assessment of immunodeficiency and immune competence in patients where B cell function (humoral immunity) is compromised. It is currently used as a research tool, as it has not been diagnostically validated, but is informative in primary antibody immunodeficiency conditions such as common variable immunodeficiency (CVID), hyper-IgM syndromes (CD40L, CD40, AID, UNG and NEMO), and in XLP (SAP and XIAP); assessing B cell subset reconstitution after stem cell or bone marrow transplant and assessing response to B cell-depleting immunotherapy (eg Rituximab). It may be informative in identifying defects in TACI and BAFF-R in patients presenting with clinical symptoms and other laboratory features consistent with CVID. Notably, transitional cells are also increased in SLE and Sjogrens syndrome, and plasmablasts are increased in multiple myeloma. Irreversible depletion of memory B cells is also described in HIV-1 infection.

Patient Preparation

No Specific preparation required

Reference Range

EUROclass classification (from Wehr et al 2008).

B+	>1% B cells
B-	< 1% CD19+ B cells
sMB+	>2% switched memory B cells
smB-	<2% switched memory B cells
21 ^low	>10% CD21 low B cells
21 ^norm	<10% CD21 low B cells
Tr ^hi	>9% transitional B cells
Tr ^norm	<9% transitional B cells

Specifications

EQA Scheme?: No
EQA Status: This is a research assay only and not available for routine use.