title: Thymic and bone marrow output in individuals with 22q11.2 deletion syndrome.
abstract: BACKGROUND
  The 22q11.2 deletion syndrome (22q11.2DS) is a congenital multisystem anomaly characterized by typical facial features, palatal anomalies, congenital heart defects, hypocalcemia, immunodeficiency, and cognitive and neuropsychiatric symptoms. The aim of our study was to investigate T- and B-lymphocyte characteristics associated with 22q11.2DS.
  
  
  METHODS
  Seventy-five individuals with 22q11.2DS were tested for T and B lymphocytes by examination of T-cell receptor rearrangement excision circles (TRECs) and B-cell κ-deleting recombination excision circles (KRECs), respectively.
  
  
  RESULTS
  The 22q11.2DS individuals displayed low levels of TRECs, while exhibiting normal levels of KRECs. There was a significant positive correlation between TREC and KREC in the 22q11.2DS group, but not in controls. Both TREC and KREC levels showed a significant decrease with age and only TREC was low in 22q11.2DS individuals with recurrent infections. No difference in TREC levels was found between 22q11.2DS individuals who underwent heart surgery (with or without thymectomy) and those who did not.
  
  
  CONCLUSIONS
  T-cell immunodeficiency in 22q11.2DS includes low TREC levels, which may contribute to recurrent infections in individuals with this syndrome. A correlation between T- and B-cell abnormalities in 22q11.2DS was identified. The B-cell abnormalities could account for part of the immunological deficiency seen in 22q11.2DS.
authors.affiliation: 1] Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel [2] The Behavioral Neurogenetics Center, Sheba Medical Center, Tel Hashomer, Israel [3] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Nina
authors.initials: N
authors.lastname: Dar
authors.affiliation: 1] The Behavioral Neurogenetics Center, Sheba Medical Center, Tel Hashomer, Israel [2] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Doron
authors.initials: D
authors.lastname: Gothelf
authors.affiliation: Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: David
authors.identifier: 0000000334150077
authors.initials: D
authors.lastname: Korn
authors.affiliation: Felsenstein Medical Research Center, Petah Tikva, Israel.
authors.forename: Amos
authors.initials: A
authors.lastname: Frisch
authors.affiliation: 1] Felsenstein Medical Research Center, Petah Tikva, Israel [2] Geha Mental Health Center, Petah Tikva, Israel.
authors.forename: Abraham
authors.initials: A
authors.lastname: Weizman
authors.affiliation: Felsenstein Medical Research Center, Petah Tikva, Israel.
authors.forename: Elena
authors.initials: E
authors.lastname: Michaelovsky
authors.affiliation: Felsenstein Medical Research Center, Petah Tikva, Israel.
authors.forename: Miri
authors.initials: M
authors.lastname: Carmel
authors.affiliation: 1] Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel [2] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel [3] Pediatric Endocrinology Unit, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Yonatan
authors.initials: Y
authors.lastname: Yeshayahu
authors.affiliation: 1] Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel [2] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Gal
authors.initials: G
authors.lastname: Dubnov-Raz
authors.affiliation: 1] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel [2] Department of Pediatric Critical Care, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Itai M
authors.initials: IM
authors.lastname: Pessach
authors.affiliation: Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Amos J
authors.initials: AJ
authors.lastname: Simon
authors.affiliation: Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Atar
authors.initials: A
authors.lastname: Lev
authors.affiliation: 1] Pediatric Department B and Immunology Services, Jeffrey Modell Foundation Center, Sheba Medical Center, Tel Hashomer, Israel [2] Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Affiliated to the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Raz
authors.initials: R
authors.lastname: Somech
mesh_terms: D000293:Adolescent; D000328:Adult; D001402:B-Lymphocytes / Q000166:cytology; D001853:Bone Marrow / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D004062:DiGeorge Syndrome / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D005260:Female; D015322:Gene Rearrangement, B-Lymphocyte; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D008297:Male; D011995:Recombination, Genetic; D013601:T-Lymphocytes / Q000166:cytology; D013950:Thymus Gland / Q000473:pathology*; D055815:Young Adult