The immune deficiency of chromosome 22q11.2 deletion syndrome

Am J Med Genet A. 2017 Sep;173(9):2366-2372. doi: 10.1002/ajmg.a.38319. Epub 2017 Jun 19.

Abstract

The syndrome originally described by Dr. Angelo DiGeorge had immunodeficiency as a central component. When a 22q11.2 deletion was identified as the cause in the majority of patients with DiGeorge syndrome, the clinical features of 22q11.2 deletion syndrome became so expansive that the immunodeficiency became less prominent in our thinking about the syndrome. This review will focus on the immune system and the changes in our understanding over the past 50 years. Initially characterized as a pure defect in T cell development, we now appreciate that many of the clinical features related to the immunodeficiency are well downstream of the limitation imposed by a small thymus. Dysfunctional B cells presumed to be secondary to compromised T cell help, issues related to T cell exhaustion, and high rates of atopy and autoimmunity are aspects of management that require consideration for optimal clinical care and for designing a cogent monitoring approach. New data on atopy are presented to further demonstrate the association.

Keywords: DiGeorge; IgG; T cells; allergy; malignancy.

Publication types

  • Review

MeSH terms

  • Chromosome Deletion
  • Chromosomes, Human, Pair 22 / genetics*
  • DiGeorge Syndrome / genetics*
  • DiGeorge Syndrome / immunology
  • DiGeorge Syndrome / pathology
  • Humans
  • Immunologic Deficiency Syndromes / genetics*
  • Immunologic Deficiency Syndromes / immunology
  • Immunologic Deficiency Syndromes / pathology
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / pathology