title: B-cell subsets in patients with transient hypogammaglobulinemia of infancy, partial IgA deficiency, and selective IgM deficiency.
abstract: BACKGROUND
  The pathogenesis of some primary humoral immunodeficiencies, such as transient hypogammaglobulinemia of infancy (THI) and immunoglobulin (Ig) A deficiency, remains unknown and can render diagnosis problematic.
  
  
  OBJECTIVE
  In the present study, we used flow cytometry to analyze peripheral blood B-cell subsets in patients with THI and unclassified hypogammaglobulinemia (UCH), partial IgA deficiency, and selective IgM deficiency.
  
  
  METHODS
  The study population comprised 41 patients with hypogammaglobulinemia (THI, 18; UCH, 23), 16 patients with partial IgA deficiency, and 16 patients with selective IgM deficiency who were admitted to Ankara University Department of Pediatric Immunology-Allergy between January 2010 and April 2011, as well as 29 healthy controls. B-cell subsets were examined according to the EUROclass classification.
  
  
  RESULTS
  Age at diagnosis in the hypogammaglobulinemia group ranged between-14 months and 13 years (median, 26 months). Naive B-cell percentages were significantly higher and activated B-cell values lower in the THI patients than in the UCH patients and age-matched healthy controls. Nonswitched (IgM+CD27+IgD+) memory B-cell values were found to be significantly lower in patients with selective IgM deficiency than in healthy controls. No significant differences in B-cell subsets were found in patients with partial IgA deficiency.
  
  
  CONCLUSIONS
  Previous reports show that reduced class-switched memory B cell values are associated with CVID, THI, and selective IgA deficiency. Our findings did not support these reports. Furthermore, we observed that naive B cell values were higher in patients with THI. A maturation defect could play a role in the pathogenesis of THI.
authors: Department of Pediatric Immunology-Allergy, Ankara University School of Medicine, Ankara, Turkey. fero176tr@hotmail.com
authors: F E
authors: FE
authors: Cipe
authors: F
authors: F
authors: Doğu
authors: D
authors: D
authors: Güloğlu
authors: C
authors: C
authors: Aytekin
authors: M
authors: M
authors: Polat
authors: Z
authors: Z
authors: Biyikli
authors: A
authors: A
authors: Ikincioğullari
mesh_terms: D000293:Adolescent; D000361:Agammaglobulinemia / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D016175:B-Lymphocyte Subsets / Q000276:immunology* / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D006801:Humans; D017098:IgA Deficiency / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D007070:Immunoglobulin A / Q000235:genetics / Q000276:immunology*; D017578:Immunoglobulin Class Switching; D007072:Immunoglobulin D / Q000235:genetics / Q000276:immunology; D007075:Immunoglobulin M / Q000172:deficiency / Q000235:genetics / Q000276:immunology*; D007156:Immunologic Memory; D007223:Infant; D008297:Male
chemical_list: D007070:Immunoglobulin A; D007072:Immunoglobulin D; D007075:Immunoglobulin M