title: Serum soluble CD23 in patients with hypogammaglobulinaemia.
abstract: Serum levels of the soluble form of the low-affinity receptor for IgE (FcERII, CD23) (sCD23) are elevated in autoimmune conditions associated with hypergammaglobulinaemia and B cell hyperactivity. Very high levels of sCD23 are found in patients with B-chronic lymphatic leukaemia (B-CLL) who are, however, frequently hypogammaglobulinaemic. We therefore compared the serum levels of sCD23 in healthy controls (n = 33) with three conditions associated with hypogammaglobulinaemia (HGG) and varying B cell numbers: X-linked agammaglobulinaemia (XLA, n = 12), common variable immunodeficiency (CVI, n = 20) and B-chronic lymphatic leukaemia (n = 33). Serum levels of sCD23 showed a significant correlation with the CD19+ B cell count in both normals and patients with CVI (r = 0.65, P < 0.0001). Amongst the different clinical groups, serum levels of sCD23 were increased in the order XLA < CVI < normals < CLL (medians 2.5, 7.7, 11.1 and 540, respectively; P < 0.001 for all comparisons except CVI versus normals P < 0.03 in a one-tailed test). In the CVI group, serum sCD23 was lowest amongst four patients with low B cell numbers. There was no overlap in sCD23 between patients with XLA and this subgroup of CVI patients. Serum sCD23 is, therefore, derived predominantly from B cells, and is significantly related to the peripheral blood B cell count.
authors.affiliation: Regional Department of Immunology, St Mary's Hospital, Manchester, UK.
authors.forename: A S
authors.initials: AS
authors.lastname: Bansal
authors.forename: M R
authors.initials: MR
authors.lastname: Haeney
authors.forename: S
authors.initials: S
authors.lastname: Cochrane
authors.forename: R S
authors.initials: RS
authors.lastname: Pumphrey
authors.forename: L M
authors.initials: LM
authors.lastname: Green
authors.forename: M
authors.initials: M
authors.lastname: Bhavnani
authors.forename: P B
authors.initials: PB
authors.lastname: Wilson
mesh_terms: D000361:Agammaglobulinemia / Q000235:genetics / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D017074:Common Variable Immunodeficiency / Q000276:immunology; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology; D007958:Leukocyte Count; D008297:Male; D017455:Receptors, IgE / Q000378:metabolism*; D014960:X Chromosome
chemical_list: D017455:Receptors, IgE